essay on global air pollution

An official website of the United States government

The .gov means it’s official. Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

The site is secure. The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

• Publications
• Account settings

The PMC website is updating on October 15, 2024. Learn More or Try it out now .

• Advanced Search
• Journal List
• Front Public Health

Environmental and Health Impacts of Air Pollution: A Review

Ioannis manisalidis.

1 Delphis S.A., Kifisia, Greece

2 Laboratory of Hygiene and Environmental Protection, Faculty of Medicine, Democritus University of Thrace, Alexandroupolis, Greece

Elisavet Stavropoulou

3 Centre Hospitalier Universitaire Vaudois (CHUV), Service de Médicine Interne, Lausanne, Switzerland

Agathangelos Stavropoulos

4 School of Social and Political Sciences, University of Glasgow, Glasgow, United Kingdom

Eugenia Bezirtzoglou

One of our era's greatest scourges is air pollution, on account not only of its impact on climate change but also its impact on public and individual health due to increasing morbidity and mortality. There are many pollutants that are major factors in disease in humans. Among them, Particulate Matter (PM), particles of variable but very small diameter, penetrate the respiratory system via inhalation, causing respiratory and cardiovascular diseases, reproductive and central nervous system dysfunctions, and cancer. Despite the fact that ozone in the stratosphere plays a protective role against ultraviolet irradiation, it is harmful when in high concentration at ground level, also affecting the respiratory and cardiovascular system. Furthermore, nitrogen oxide, sulfur dioxide, Volatile Organic Compounds (VOCs), dioxins, and polycyclic aromatic hydrocarbons (PAHs) are all considered air pollutants that are harmful to humans. Carbon monoxide can even provoke direct poisoning when breathed in at high levels. Heavy metals such as lead, when absorbed into the human body, can lead to direct poisoning or chronic intoxication, depending on exposure. Diseases occurring from the aforementioned substances include principally respiratory problems such as Chronic Obstructive Pulmonary Disease (COPD), asthma, bronchiolitis, and also lung cancer, cardiovascular events, central nervous system dysfunctions, and cutaneous diseases. Last but not least, climate change resulting from environmental pollution affects the geographical distribution of many infectious diseases, as do natural disasters. The only way to tackle this problem is through public awareness coupled with a multidisciplinary approach by scientific experts; national and international organizations must address the emergence of this threat and propose sustainable solutions.

Approach to the Problem

The interactions between humans and their physical surroundings have been extensively studied, as multiple human activities influence the environment. The environment is a coupling of the biotic (living organisms and microorganisms) and the abiotic (hydrosphere, lithosphere, and atmosphere).

Pollution is defined as the introduction into the environment of substances harmful to humans and other living organisms. Pollutants are harmful solids, liquids, or gases produced in higher than usual concentrations that reduce the quality of our environment.

Human activities have an adverse effect on the environment by polluting the water we drink, the air we breathe, and the soil in which plants grow. Although the industrial revolution was a great success in terms of technology, society, and the provision of multiple services, it also introduced the production of huge quantities of pollutants emitted into the air that are harmful to human health. Without any doubt, the global environmental pollution is considered an international public health issue with multiple facets. Social, economic, and legislative concerns and lifestyle habits are related to this major problem. Clearly, urbanization and industrialization are reaching unprecedented and upsetting proportions worldwide in our era. Anthropogenic air pollution is one of the biggest public health hazards worldwide, given that it accounts for about 9 million deaths per year ( 1 ).

Without a doubt, all of the aforementioned are closely associated with climate change, and in the event of danger, the consequences can be severe for mankind ( 2 ). Climate changes and the effects of global planetary warming seriously affect multiple ecosystems, causing problems such as food safety issues, ice and iceberg melting, animal extinction, and damage to plants ( 3 , 4 ).

Air pollution has various health effects. The health of susceptible and sensitive individuals can be impacted even on low air pollution days. Short-term exposure to air pollutants is closely related to COPD (Chronic Obstructive Pulmonary Disease), cough, shortness of breath, wheezing, asthma, respiratory disease, and high rates of hospitalization (a measurement of morbidity).

The long-term effects associated with air pollution are chronic asthma, pulmonary insufficiency, cardiovascular diseases, and cardiovascular mortality. According to a Swedish cohort study, diabetes seems to be induced after long-term air pollution exposure ( 5 ). Moreover, air pollution seems to have various malign health effects in early human life, such as respiratory, cardiovascular, mental, and perinatal disorders ( 3 ), leading to infant mortality or chronic disease in adult age ( 6 ).

National reports have mentioned the increased risk of morbidity and mortality ( 1 ). These studies were conducted in many places around the world and show a correlation between daily ranges of particulate matter (PM) concentration and daily mortality. Climate shifts and global planetary warming ( 3 ) could aggravate the situation. Besides, increased hospitalization (an index of morbidity) has been registered among the elderly and susceptible individuals for specific reasons. Fine and ultrafine particulate matter seems to be associated with more serious illnesses ( 6 ), as it can invade the deepest parts of the airways and more easily reach the bloodstream.

Air pollution mainly affects those living in large urban areas, where road emissions contribute the most to the degradation of air quality. There is also a danger of industrial accidents, where the spread of a toxic fog can be fatal to the populations of the surrounding areas. The dispersion of pollutants is determined by many parameters, most notably atmospheric stability and wind ( 6 ).

In developing countries ( 7 ), the problem is more serious due to overpopulation and uncontrolled urbanization along with the development of industrialization. This leads to poor air quality, especially in countries with social disparities and a lack of information on sustainable management of the environment. The use of fuels such as wood fuel or solid fuel for domestic needs due to low incomes exposes people to bad-quality, polluted air at home. It is of note that three billion people around the world are using the above sources of energy for their daily heating and cooking needs ( 8 ). In developing countries, the women of the household seem to carry the highest risk for disease development due to their longer duration exposure to the indoor air pollution ( 8 , 9 ). Due to its fast industrial development and overpopulation, China is one of the Asian countries confronting serious air pollution problems ( 10 , 11 ). The lung cancer mortality observed in China is associated with fine particles ( 12 ). As stated already, long-term exposure is associated with deleterious effects on the cardiovascular system ( 3 , 5 ). However, it is interesting to note that cardiovascular diseases have mostly been observed in developed and high-income countries rather than in the developing low-income countries exposed highly to air pollution ( 13 ). Extreme air pollution is recorded in India, where the air quality reaches hazardous levels. New Delhi is one of the more polluted cities in India. Flights in and out of New Delhi International Airport are often canceled due to the reduced visibility associated with air pollution. Pollution is occurring both in urban and rural areas in India due to the fast industrialization, urbanization, and rise in use of motorcycle transportation. Nevertheless, biomass combustion associated with heating and cooking needs and practices is a major source of household air pollution in India and in Nepal ( 14 , 15 ). There is spatial heterogeneity in India, as areas with diverse climatological conditions and population and education levels generate different indoor air qualities, with higher PM 2.5 observed in North Indian states (557–601 μg/m 3 ) compared to the Southern States (183–214 μg/m 3 ) ( 16 , 17 ). The cold climate of the North Indian areas may be the main reason for this, as longer periods at home and more heating are necessary compared to in the tropical climate of Southern India. Household air pollution in India is associated with major health effects, especially in women and young children, who stay indoors for longer periods. Chronic obstructive respiratory disease (CORD) and lung cancer are mostly observed in women, while acute lower respiratory disease is seen in young children under 5 years of age ( 18 ).

Accumulation of air pollution, especially sulfur dioxide and smoke, reaching 1,500 mg/m3, resulted in an increase in the number of deaths (4,000 deaths) in December 1952 in London and in 1963 in New York City (400 deaths) ( 19 ). An association of pollution with mortality was reported on the basis of monitoring of outdoor pollution in six US metropolitan cities ( 20 ). In every case, it seems that mortality was closely related to the levels of fine, inhalable, and sulfate particles more than with the levels of total particulate pollution, aerosol acidity, sulfur dioxide, or nitrogen dioxide ( 20 ).

Furthermore, extremely high levels of pollution are reported in Mexico City and Rio de Janeiro, followed by Milan, Ankara, Melbourne, Tokyo, and Moscow ( 19 ).

Based on the magnitude of the public health impact, it is certain that different kinds of interventions should be taken into account. Success and effectiveness in controlling air pollution, specifically at the local level, have been reported. Adequate technological means are applied considering the source and the nature of the emission as well as its impact on health and the environment. The importance of point sources and non-point sources of air pollution control is reported by Schwela and Köth-Jahr ( 21 ). Without a doubt, a detailed emission inventory must record all sources in a given area. Beyond considering the above sources and their nature, topography and meteorology should also be considered, as stated previously. Assessment of the control policies and methods is often extrapolated from the local to the regional and then to the global scale. Air pollution may be dispersed and transported from one region to another area located far away. Air pollution management means the reduction to acceptable levels or possible elimination of air pollutants whose presence in the air affects our health or the environmental ecosystem. Private and governmental entities and authorities implement actions to ensure the air quality ( 22 ). Air quality standards and guidelines were adopted for the different pollutants by the WHO and EPA as a tool for the management of air quality ( 1 , 23 ). These standards have to be compared to the emissions inventory standards by causal analysis and dispersion modeling in order to reveal the problematic areas ( 24 ). Inventories are generally based on a combination of direct measurements and emissions modeling ( 24 ).

As an example, we state here the control measures at the source through the use of catalytic converters in cars. These are devices that turn the pollutants and toxic gases produced from combustion engines into less-toxic pollutants by catalysis through redox reactions ( 25 ). In Greece, the use of private cars was restricted by tracking their license plates in order to reduce traffic congestion during rush hour ( 25 ).

Concerning industrial emissions, collectors and closed systems can keep the air pollution to the minimal standards imposed by legislation ( 26 ).

Current strategies to improve air quality require an estimation of the economic value of the benefits gained from proposed programs. These proposed programs by public authorities, and directives are issued with guidelines to be respected.

In Europe, air quality limit values AQLVs (Air Quality Limit Values) are issued for setting off planning claims ( 27 ). In the USA, the NAAQS (National Ambient Air Quality Standards) establish the national air quality limit values ( 27 ). While both standards and directives are based on different mechanisms, significant success has been achieved in the reduction of overall emissions and associated health and environmental effects ( 27 ). The European Directive identifies geographical areas of risk exposure as monitoring/assessment zones to record the emission sources and levels of air pollution ( 27 ), whereas the USA establishes global geographical air quality criteria according to the severity of their air quality problem and records all sources of the pollutants and their precursors ( 27 ).

In this vein, funds have been financing, directly or indirectly, projects related to air quality along with the technical infrastructure to maintain good air quality. These plans focus on an inventory of databases from air quality environmental planning awareness campaigns. Moreover, pollution measures of air emissions may be taken for vehicles, machines, and industries in urban areas.

Technological innovation can only be successful if it is able to meet the needs of society. In this sense, technology must reflect the decision-making practices and procedures of those involved in risk assessment and evaluation and act as a facilitator in providing information and assessments to enable decision makers to make the best decisions possible. Summarizing the aforementioned in order to design an effective air quality control strategy, several aspects must be considered: environmental factors and ambient air quality conditions, engineering factors and air pollutant characteristics, and finally, economic operating costs for technological improvement and administrative and legal costs. Considering the economic factor, competitiveness through neoliberal concepts is offering a solution to environmental problems ( 22 ).

The development of environmental governance, along with technological progress, has initiated the deployment of a dialogue. Environmental politics has created objections and points of opposition between different political parties, scientists, media, and governmental and non-governmental organizations ( 22 ). Radical environmental activism actions and movements have been created ( 22 ). The rise of the new information and communication technologies (ICTs) are many times examined as to whether and in which way they have influenced means of communication and social movements such as activism ( 28 ). Since the 1990s, the term “digital activism” has been used increasingly and in many different disciplines ( 29 ). Nowadays, multiple digital technologies can be used to produce a digital activism outcome on environmental issues. More specifically, devices with online capabilities such as computers or mobile phones are being used as a way to pursue change in political and social affairs ( 30 ).

In the present paper, we focus on the sources of environmental pollution in relation to public health and propose some solutions and interventions that may be of interest to environmental legislators and decision makers.

Sources of Exposure

It is known that the majority of environmental pollutants are emitted through large-scale human activities such as the use of industrial machinery, power-producing stations, combustion engines, and cars. Because these activities are performed at such a large scale, they are by far the major contributors to air pollution, with cars estimated to be responsible for approximately 80% of today's pollution ( 31 ). Some other human activities are also influencing our environment to a lesser extent, such as field cultivation techniques, gas stations, fuel tanks heaters, and cleaning procedures ( 32 ), as well as several natural sources, such as volcanic and soil eruptions and forest fires.

The classification of air pollutants is based mainly on the sources producing pollution. Therefore, it is worth mentioning the four main sources, following the classification system: Major sources, Area sources, Mobile sources, and Natural sources.

Major sources include the emission of pollutants from power stations, refineries, and petrochemicals, the chemical and fertilizer industries, metallurgical and other industrial plants, and, finally, municipal incineration.

Indoor area sources include domestic cleaning activities, dry cleaners, printing shops, and petrol stations.

Mobile sources include automobiles, cars, railways, airways, and other types of vehicles.

Finally, natural sources include, as stated previously, physical disasters ( 33 ) such as forest fire, volcanic erosion, dust storms, and agricultural burning.

However, many classification systems have been proposed. Another type of classification is a grouping according to the recipient of the pollution, as follows:

Air pollution is determined as the presence of pollutants in the air in large quantities for long periods. Air pollutants are dispersed particles, hydrocarbons, CO, CO 2 , NO, NO 2 , SO 3 , etc.

Water pollution is organic and inorganic charge and biological charge ( 10 ) at high levels that affect the water quality ( 34 , 35 ).

Soil pollution occurs through the release of chemicals or the disposal of wastes, such as heavy metals, hydrocarbons, and pesticides.

Air pollution can influence the quality of soil and water bodies by polluting precipitation, falling into water and soil environments ( 34 , 36 ). Notably, the chemistry of the soil can be amended due to acid precipitation by affecting plants, cultures, and water quality ( 37 ). Moreover, movement of heavy metals is favored by soil acidity, and metals are so then moving into the watery environment. It is known that heavy metals such as aluminum are noxious to wildlife and fishes. Soil quality seems to be of importance, as soils with low calcium carbonate levels are at increased jeopardy from acid rain. Over and above rain, snow and particulate matter drip into watery ' bodies ( 36 , 38 ).

Lastly, pollution is classified following type of origin:

Radioactive and nuclear pollution , releasing radioactive and nuclear pollutants into water, air, and soil during nuclear explosions and accidents, from nuclear weapons, and through handling or disposal of radioactive sewage.

Radioactive materials can contaminate surface water bodies and, being noxious to the environment, plants, animals, and humans. It is known that several radioactive substances such as radium and uranium concentrate in the bones and can cause cancers ( 38 , 39 ).

Noise pollution is produced by machines, vehicles, traffic noises, and musical installations that are harmful to our hearing.

The World Health Organization introduced the term DALYs. The DALYs for a disease or health condition is defined as the sum of the Years of Life Lost (YLL) due to premature mortality in the population and the Years Lost due to Disability (YLD) for people living with the health condition or its consequences ( 39 ). In Europe, air pollution is the main cause of disability-adjusted life years lost (DALYs), followed by noise pollution. The potential relationships of noise and air pollution with health have been studied ( 40 ). The study found that DALYs related to noise were more important than those related to air pollution, as the effects of environmental noise on cardiovascular disease were independent of air pollution ( 40 ). Environmental noise should be counted as an independent public health risk ( 40 ).

Environmental pollution occurs when changes in the physical, chemical, or biological constituents of the environment (air masses, temperature, climate, etc.) are produced.

Pollutants harm our environment either by increasing levels above normal or by introducing harmful toxic substances. Primary pollutants are directly produced from the above sources, and secondary pollutants are emitted as by-products of the primary ones. Pollutants can be biodegradable or non-biodegradable and of natural origin or anthropogenic, as stated previously. Moreover, their origin can be a unique source (point-source) or dispersed sources.

Pollutants have differences in physical and chemical properties, explaining the discrepancy in their capacity for producing toxic effects. As an example, we state here that aerosol compounds ( 41 – 43 ) have a greater toxicity than gaseous compounds due to their tiny size (solid or liquid) in the atmosphere; they have a greater penetration capacity. Gaseous compounds are eliminated more easily by our respiratory system ( 41 ). These particles are able to damage lungs and can even enter the bloodstream ( 41 ), leading to the premature deaths of millions of people yearly. Moreover, the aerosol acidity ([H+]) seems to considerably enhance the production of secondary organic aerosols (SOA), but this last aspect is not supported by other scientific teams ( 38 ).

Climate and Pollution

Air pollution and climate change are closely related. Climate is the other side of the same coin that reduces the quality of our Earth ( 44 ). Pollutants such as black carbon, methane, tropospheric ozone, and aerosols affect the amount of incoming sunlight. As a result, the temperature of the Earth is increasing, resulting in the melting of ice, icebergs, and glaciers.

In this vein, climatic changes will affect the incidence and prevalence of both residual and imported infections in Europe. Climate and weather affect the duration, timing, and intensity of outbreaks strongly and change the map of infectious diseases in the globe ( 45 ). Mosquito-transmitted parasitic or viral diseases are extremely climate-sensitive, as warming firstly shortens the pathogen incubation period and secondly shifts the geographic map of the vector. Similarly, water-warming following climate changes leads to a high incidence of waterborne infections. Recently, in Europe, eradicated diseases seem to be emerging due to the migration of population, for example, cholera, poliomyelitis, tick-borne encephalitis, and malaria ( 46 ).

The spread of epidemics is associated with natural climate disasters and storms, which seem to occur more frequently nowadays ( 47 ). Malnutrition and disequilibration of the immune system are also associated with the emerging infections affecting public health ( 48 ).

The Chikungunya virus “took the airplane” from the Indian Ocean to Europe, as outbreaks of the disease were registered in Italy ( 49 ) as well as autochthonous cases in France ( 50 ).

An increase in cryptosporidiosis in the United Kingdom and in the Czech Republic seems to have occurred following flooding ( 36 , 51 ).

As stated previously, aerosols compounds are tiny in size and considerably affect the climate. They are able to dissipate sunlight (the albedo phenomenon) by dispersing a quarter of the sun's rays back to space and have cooled the global temperature over the last 30 years ( 52 ).

Air Pollutants

The World Health Organization (WHO) reports on six major air pollutants, namely particle pollution, ground-level ozone, carbon monoxide, sulfur oxides, nitrogen oxides, and lead. Air pollution can have a disastrous effect on all components of the environment, including groundwater, soil, and air. Additionally, it poses a serious threat to living organisms. In this vein, our interest is mainly to focus on these pollutants, as they are related to more extensive and severe problems in human health and environmental impact. Acid rain, global warming, the greenhouse effect, and climate changes have an important ecological impact on air pollution ( 53 ).

Particulate Matter (PM) and Health

Studies have shown a relationship between particulate matter (PM) and adverse health effects, focusing on either short-term (acute) or long-term (chronic) PM exposure.

Particulate matter (PM) is usually formed in the atmosphere as a result of chemical reactions between the different pollutants. The penetration of particles is closely dependent on their size ( 53 ). Particulate Matter (PM) was defined as a term for particles by the United States Environmental Protection Agency ( 54 ). Particulate matter (PM) pollution includes particles with diameters of 10 micrometers (μm) or smaller, called PM 10 , and extremely fine particles with diameters that are generally 2.5 micrometers (μm) and smaller.

Particulate matter contains tiny liquid or solid droplets that can be inhaled and cause serious health effects ( 55 ). Particles <10 μm in diameter (PM 10 ) after inhalation can invade the lungs and even reach the bloodstream. Fine particles, PM 2.5 , pose a greater risk to health ( 6 , 56 ) ( Table 1 ).

Penetrability according to particle size.

Multiple epidemiological studies have been performed on the health effects of PM. A positive relation was shown between both short-term and long-term exposures of PM 2.5 and acute nasopharyngitis ( 56 ). In addition, long-term exposure to PM for years was found to be related to cardiovascular diseases and infant mortality.

Those studies depend on PM 2.5 monitors and are restricted in terms of study area or city area due to a lack of spatially resolved daily PM 2.5 concentration data and, in this way, are not representative of the entire population. Following a recent epidemiological study by the Department of Environmental Health at Harvard School of Public Health (Boston, MA) ( 57 ), it was reported that, as PM 2.5 concentrations vary spatially, an exposure error (Berkson error) seems to be produced, and the relative magnitudes of the short- and long-term effects are not yet completely elucidated. The team developed a PM 2.5 exposure model based on remote sensing data for assessing short- and long-term human exposures ( 57 ). This model permits spatial resolution in short-term effects plus the assessment of long-term effects in the whole population.

Moreover, respiratory diseases and affection of the immune system are registered as long-term chronic effects ( 58 ). It is worth noting that people with asthma, pneumonia, diabetes, and respiratory and cardiovascular diseases are especially susceptible and vulnerable to the effects of PM. PM 2.5 , followed by PM 10 , are strongly associated with diverse respiratory system diseases ( 59 ), as their size permits them to pierce interior spaces ( 60 ). The particles produce toxic effects according to their chemical and physical properties. The components of PM 10 and PM 2.5 can be organic (polycyclic aromatic hydrocarbons, dioxins, benzene, 1-3 butadiene) or inorganic (carbon, chlorides, nitrates, sulfates, metals) in nature ( 55 ).

Particulate Matter (PM) is divided into four main categories according to type and size ( 61 ) ( Table 2 ).

Types and sizes of particulate Matter (PM).

Gas contaminants include PM in aerial masses.

Particulate contaminants include contaminants such as smog, soot, tobacco smoke, oil smoke, fly ash, and cement dust.

Biological Contaminants are microorganisms (bacteria, viruses, fungi, mold, and bacterial spores), cat allergens, house dust and allergens, and pollen.

Types of Dust include suspended atmospheric dust, settling dust, and heavy dust.

Finally, another fact is that the half-lives of PM 10 and PM 2.5 particles in the atmosphere is extended due to their tiny dimensions; this permits their long-lasting suspension in the atmosphere and even their transfer and spread to distant destinations where people and the environment may be exposed to the same magnitude of pollution ( 53 ). They are able to change the nutrient balance in watery ecosystems, damage forests and crops, and acidify water bodies.

As stated, PM 2.5 , due to their tiny size, are causing more serious health effects. These aforementioned fine particles are the main cause of the “haze” formation in different metropolitan areas ( 12 , 13 , 61 ).

Ozone Impact in the Atmosphere

Ozone (O 3 ) is a gas formed from oxygen under high voltage electric discharge ( 62 ). It is a strong oxidant, 52% stronger than chlorine. It arises in the stratosphere, but it could also arise following chain reactions of photochemical smog in the troposphere ( 63 ).

Ozone can travel to distant areas from its initial source, moving with air masses ( 64 ). It is surprising that ozone levels over cities are low in contrast to the increased amounts occuring in urban areas, which could become harmful for cultures, forests, and vegetation ( 65 ) as it is reducing carbon assimilation ( 66 ). Ozone reduces growth and yield ( 47 , 48 ) and affects the plant microflora due to its antimicrobial capacity ( 67 , 68 ). In this regard, ozone acts upon other natural ecosystems, with microflora ( 69 , 70 ) and animal species changing their species composition ( 71 ). Ozone increases DNA damage in epidermal keratinocytes and leads to impaired cellular function ( 72 ).

Ground-level ozone (GLO) is generated through a chemical reaction between oxides of nitrogen and VOCs emitted from natural sources and/or following anthropogenic activities.

Ozone uptake usually occurs by inhalation. Ozone affects the upper layers of the skin and the tear ducts ( 73 ). A study of short-term exposure of mice to high levels of ozone showed malondialdehyde formation in the upper skin (epidermis) but also depletion in vitamins C and E. It is likely that ozone levels are not interfering with the skin barrier function and integrity to predispose to skin disease ( 74 ).

Due to the low water-solubility of ozone, inhaled ozone has the capacity to penetrate deeply into the lungs ( 75 ).

Toxic effects induced by ozone are registered in urban areas all over the world, causing biochemical, morphologic, functional, and immunological disorders ( 76 ).

The European project (APHEA2) focuses on the acute effects of ambient ozone concentrations on mortality ( 77 ). Daily ozone concentrations compared to the daily number of deaths were reported from different European cities for a 3-year period. During the warm period of the year, an observed increase in ozone concentration was associated with an increase in the daily number of deaths (0.33%), in the number of respiratory deaths (1.13%), and in the number of cardiovascular deaths (0.45%). No effect was observed during wintertime.

Carbon Monoxide (CO)

Carbon monoxide is produced by fossil fuel when combustion is incomplete. The symptoms of poisoning due to inhaling carbon monoxide include headache, dizziness, weakness, nausea, vomiting, and, finally, loss of consciousness.

The affinity of carbon monoxide to hemoglobin is much greater than that of oxygen. In this vein, serious poisoning may occur in people exposed to high levels of carbon monoxide for a long period of time. Due to the loss of oxygen as a result of the competitive binding of carbon monoxide, hypoxia, ischemia, and cardiovascular disease are observed.

Carbon monoxide affects the greenhouses gases that are tightly connected to global warming and climate. This should lead to an increase in soil and water temperatures, and extreme weather conditions or storms may occur ( 68 ).

However, in laboratory and field experiments, it has been seen to produce increased plant growth ( 78 ).

Nitrogen Oxide (NO 2 )

Nitrogen oxide is a traffic-related pollutant, as it is emitted from automobile motor engines ( 79 , 80 ). It is an irritant of the respiratory system as it penetrates deep in the lung, inducing respiratory diseases, coughing, wheezing, dyspnea, bronchospasm, and even pulmonary edema when inhaled at high levels. It seems that concentrations over 0.2 ppm produce these adverse effects in humans, while concentrations higher than 2.0 ppm affect T-lymphocytes, particularly the CD8+ cells and NK cells that produce our immune response ( 81 ).It is reported that long-term exposure to high levels of nitrogen dioxide can be responsible for chronic lung disease. Long-term exposure to NO 2 can impair the sense of smell ( 81 ).

However, systems other than respiratory ones can be involved, as symptoms such as eye, throat, and nose irritation have been registered ( 81 ).

High levels of nitrogen dioxide are deleterious to crops and vegetation, as they have been observed to reduce crop yield and plant growth efficiency. Moreover, NO 2 can reduce visibility and discolor fabrics ( 81 ).

Sulfur Dioxide (SO 2 )

Sulfur dioxide is a harmful gas that is emitted mainly from fossil fuel consumption or industrial activities. The annual standard for SO 2 is 0.03 ppm ( 82 ). It affects human, animal, and plant life. Susceptible people as those with lung disease, old people, and children, who present a higher risk of damage. The major health problems associated with sulfur dioxide emissions in industrialized areas are respiratory irritation, bronchitis, mucus production, and bronchospasm, as it is a sensory irritant and penetrates deep into the lung converted into bisulfite and interacting with sensory receptors, causing bronchoconstriction. Moreover, skin redness, damage to the eyes (lacrimation and corneal opacity) and mucous membranes, and worsening of pre-existing cardiovascular disease have been observed ( 81 ).

Environmental adverse effects, such as acidification of soil and acid rain, seem to be associated with sulfur dioxide emissions ( 83 ).

Lead is a heavy metal used in different industrial plants and emitted from some petrol motor engines, batteries, radiators, waste incinerators, and waste waters ( 84 ).

Moreover, major sources of lead pollution in the air are metals, ore, and piston-engine aircraft. Lead poisoning is a threat to public health due to its deleterious effects upon humans, animals, and the environment, especially in the developing countries.

Exposure to lead can occur through inhalation, ingestion, and dermal absorption. Trans- placental transport of lead was also reported, as lead passes through the placenta unencumbered ( 85 ). The younger the fetus is, the more harmful the toxic effects. Lead toxicity affects the fetal nervous system; edema or swelling of the brain is observed ( 86 ). Lead, when inhaled, accumulates in the blood, soft tissue, liver, lung, bones, and cardiovascular, nervous, and reproductive systems. Moreover, loss of concentration and memory, as well as muscle and joint pain, were observed in adults ( 85 , 86 ).

Children and newborns ( 87 ) are extremely susceptible even to minimal doses of lead, as it is a neurotoxicant and causes learning disabilities, impairment of memory, hyperactivity, and even mental retardation.

Elevated amounts of lead in the environment are harmful to plants and crop growth. Neurological effects are observed in vertebrates and animals in association with high lead levels ( 88 ).

Polycyclic Aromatic Hydrocarbons(PAHs)

The distribution of PAHs is ubiquitous in the environment, as the atmosphere is the most important means of their dispersal. They are found in coal and in tar sediments. Moreover, they are generated through incomplete combustion of organic matter as in the cases of forest fires, incineration, and engines ( 89 ). PAH compounds, such as benzopyrene, acenaphthylene, anthracene, and fluoranthene are recognized as toxic, mutagenic, and carcinogenic substances. They are an important risk factor for lung cancer ( 89 ).

Volatile Organic Compounds(VOCs)

Volatile organic compounds (VOCs), such as toluene, benzene, ethylbenzene, and xylene ( 90 ), have been found to be associated with cancer in humans ( 91 ). The use of new products and materials has actually resulted in increased concentrations of VOCs. VOCs pollute indoor air ( 90 ) and may have adverse effects on human health ( 91 ). Short-term and long-term adverse effects on human health are observed. VOCs are responsible for indoor air smells. Short-term exposure is found to cause irritation of eyes, nose, throat, and mucosal membranes, while those of long duration exposure include toxic reactions ( 92 ). Predictable assessment of the toxic effects of complex VOC mixtures is difficult to estimate, as these pollutants can have synergic, antagonistic, or indifferent effects ( 91 , 93 ).

Dioxins originate from industrial processes but also come from natural processes, such as forest fires and volcanic eruptions. They accumulate in foods such as meat and dairy products, fish and shellfish, and especially in the fatty tissue of animals ( 94 ).

Short-period exhibition to high dioxin concentrations may result in dark spots and lesions on the skin ( 94 ). Long-term exposure to dioxins can cause developmental problems, impairment of the immune, endocrine and nervous systems, reproductive infertility, and cancer ( 94 ).

Without any doubt, fossil fuel consumption is responsible for a sizeable part of air contamination. This contamination may be anthropogenic, as in agricultural and industrial processes or transportation, while contamination from natural sources is also possible. Interestingly, it is of note that the air quality standards established through the European Air Quality Directive are somewhat looser than the WHO guidelines, which are stricter ( 95 ).

Effect of Air Pollution on Health

The most common air pollutants are ground-level ozone and Particulates Matter (PM). Air pollution is distinguished into two main types:

Outdoor pollution is the ambient air pollution.

Indoor pollution is the pollution generated by household combustion of fuels.

People exposed to high concentrations of air pollutants experience disease symptoms and states of greater and lesser seriousness. These effects are grouped into short- and long-term effects affecting health.

Susceptible populations that need to be aware of health protection measures include old people, children, and people with diabetes and predisposing heart or lung disease, especially asthma.

As extensively stated previously, according to a recent epidemiological study from Harvard School of Public Health, the relative magnitudes of the short- and long-term effects have not been completely clarified ( 57 ) due to the different epidemiological methodologies and to the exposure errors. New models are proposed for assessing short- and long-term human exposure data more successfully ( 57 ). Thus, in the present section, we report the more common short- and long-term health effects but also general concerns for both types of effects, as these effects are often dependent on environmental conditions, dose, and individual susceptibility.

Short-term effects are temporary and range from simple discomfort, such as irritation of the eyes, nose, skin, throat, wheezing, coughing and chest tightness, and breathing difficulties, to more serious states, such as asthma, pneumonia, bronchitis, and lung and heart problems. Short-term exposure to air pollution can also cause headaches, nausea, and dizziness.

These problems can be aggravated by extended long-term exposure to the pollutants, which is harmful to the neurological, reproductive, and respiratory systems and causes cancer and even, rarely, deaths.

The long-term effects are chronic, lasting for years or the whole life and can even lead to death. Furthermore, the toxicity of several air pollutants may also induce a variety of cancers in the long term ( 96 ).

As stated already, respiratory disorders are closely associated with the inhalation of air pollutants. These pollutants will invade through the airways and will accumulate at the cells. Damage to target cells should be related to the pollutant component involved and its source and dose. Health effects are also closely dependent on country, area, season, and time. An extended exposure duration to the pollutant should incline to long-term health effects in relation also to the above factors.

Particulate Matter (PMs), dust, benzene, and O 3 cause serious damage to the respiratory system ( 97 ). Moreover, there is a supplementary risk in case of existing respiratory disease such as asthma ( 98 ). Long-term effects are more frequent in people with a predisposing disease state. When the trachea is contaminated by pollutants, voice alterations may be remarked after acute exposure. Chronic obstructive pulmonary disease (COPD) may be induced following air pollution, increasing morbidity and mortality ( 99 ). Long-term effects from traffic, industrial air pollution, and combustion of fuels are the major factors for COPD risk ( 99 ).

Multiple cardiovascular effects have been observed after exposure to air pollutants ( 100 ). Changes occurred in blood cells after long-term exposure may affect cardiac functionality. Coronary arteriosclerosis was reported following long-term exposure to traffic emissions ( 101 ), while short-term exposure is related to hypertension, stroke, myocardial infracts, and heart insufficiency. Ventricle hypertrophy is reported to occur in humans after long-time exposure to nitrogen oxide (NO 2 ) ( 102 , 103 ).

Neurological effects have been observed in adults and children after extended-term exposure to air pollutants.

Psychological complications, autism, retinopathy, fetal growth, and low birth weight seem to be related to long-term air pollution ( 83 ). The etiologic agent of the neurodegenerative diseases (Alzheimer's and Parkinson's) is not yet known, although it is believed that extended exposure to air pollution seems to be a factor. Specifically, pesticides and metals are cited as etiological factors, together with diet. The mechanisms in the development of neurodegenerative disease include oxidative stress, protein aggregation, inflammation, and mitochondrial impairment in neurons ( 104 ) ( Figure 1 ).

Impact of air pollutants on the brain.

Brain inflammation was observed in dogs living in a highly polluted area in Mexico for a long period ( 105 ). In human adults, markers of systemic inflammation (IL-6 and fibrinogen) were found to be increased as an immediate response to PNC on the IL-6 level, possibly leading to the production of acute-phase proteins ( 106 ). The progression of atherosclerosis and oxidative stress seem to be the mechanisms involved in the neurological disturbances caused by long-term air pollution. Inflammation comes secondary to the oxidative stress and seems to be involved in the impairment of developmental maturation, affecting multiple organs ( 105 , 107 ). Similarly, other factors seem to be involved in the developmental maturation, which define the vulnerability to long-term air pollution. These include birthweight, maternal smoking, genetic background and socioeconomic environment, as well as education level.

However, diet, starting from breast-feeding, is another determinant factor. Diet is the main source of antioxidants, which play a key role in our protection against air pollutants ( 108 ). Antioxidants are free radical scavengers and limit the interaction of free radicals in the brain ( 108 ). Similarly, genetic background may result in a differential susceptibility toward the oxidative stress pathway ( 60 ). For example, antioxidant supplementation with vitamins C and E appears to modulate the effect of ozone in asthmatic children homozygous for the GSTM1 null allele ( 61 ). Inflammatory cytokines released in the periphery (e.g., respiratory epithelia) upregulate the innate immune Toll-like receptor 2. Such activation and the subsequent events leading to neurodegeneration have recently been observed in lung lavage in mice exposed to ambient Los Angeles (CA, USA) particulate matter ( 61 ). In children, neurodevelopmental morbidities were observed after lead exposure. These children developed aggressive and delinquent behavior, reduced intelligence, learning difficulties, and hyperactivity ( 109 ). No level of lead exposure seems to be “safe,” and the scientific community has asked the Centers for Disease Control and Prevention (CDC) to reduce the current screening guideline of 10 μg/dl ( 109 ).

It is important to state that impact on the immune system, causing dysfunction and neuroinflammation ( 104 ), is related to poor air quality. Yet, increases in serum levels of immunoglobulins (IgA, IgM) and the complement component C3 are observed ( 106 ). Another issue is that antigen presentation is affected by air pollutants, as there is an upregulation of costimulatory molecules such as CD80 and CD86 on macrophages ( 110 ).

As is known, skin is our shield against ultraviolet radiation (UVR) and other pollutants, as it is the most exterior layer of our body. Traffic-related pollutants, such as PAHs, VOCs, oxides, and PM, may cause pigmented spots on our skin ( 111 ). On the one hand, as already stated, when pollutants penetrate through the skin or are inhaled, damage to the organs is observed, as some of these pollutants are mutagenic and carcinogenic, and, specifically, they affect the liver and lung. On the other hand, air pollutants (and those in the troposphere) reduce the adverse effects of ultraviolet radiation UVR in polluted urban areas ( 111 ). Air pollutants absorbed by the human skin may contribute to skin aging, psoriasis, acne, urticaria, eczema, and atopic dermatitis ( 111 ), usually caused by exposure to oxides and photochemical smoke ( 111 ). Exposure to PM and cigarette smoking act as skin-aging agents, causing spots, dyschromia, and wrinkles. Lastly, pollutants have been associated with skin cancer ( 111 ).

Higher morbidity is reported to fetuses and children when exposed to the above dangers. Impairment in fetal growth, low birth weight, and autism have been reported ( 112 ).

Another exterior organ that may be affected is the eye. Contamination usually comes from suspended pollutants and may result in asymptomatic eye outcomes, irritation ( 112 ), retinopathy, or dry eye syndrome ( 113 , 114 ).

Environmental Impact of Air Pollution

Air pollution is harming not only human health but also the environment ( 115 ) in which we live. The most important environmental effects are as follows.

Acid rain is wet (rain, fog, snow) or dry (particulates and gas) precipitation containing toxic amounts of nitric and sulfuric acids. They are able to acidify the water and soil environments, damage trees and plantations, and even damage buildings and outdoor sculptures, constructions, and statues.

Haze is produced when fine particles are dispersed in the air and reduce the transparency of the atmosphere. It is caused by gas emissions in the air coming from industrial facilities, power plants, automobiles, and trucks.

Ozone , as discussed previously, occurs both at ground level and in the upper level (stratosphere) of the Earth's atmosphere. Stratospheric ozone is protecting us from the Sun's harmful ultraviolet (UV) rays. In contrast, ground-level ozone is harmful to human health and is a pollutant. Unfortunately, stratospheric ozone is gradually damaged by ozone-depleting substances (i.e., chemicals, pesticides, and aerosols). If this protecting stratospheric ozone layer is thinned, then UV radiation can reach our Earth, with harmful effects for human life (skin cancer) ( 116 ) and crops ( 117 ). In plants, ozone penetrates through the stomata, inducing them to close, which blocks CO 2 transfer and induces a reduction in photosynthesis ( 118 ).

Global climate change is an important issue that concerns mankind. As is known, the “greenhouse effect” keeps the Earth's temperature stable. Unhappily, anthropogenic activities have destroyed this protecting temperature effect by producing large amounts of greenhouse gases, and global warming is mounting, with harmful effects on human health, animals, forests, wildlife, agriculture, and the water environment. A report states that global warming is adding to the health risks of poor people ( 119 ).

People living in poorly constructed buildings in warm-climate countries are at high risk for heat-related health problems as temperatures mount ( 119 ).

Wildlife is burdened by toxic pollutants coming from the air, soil, or the water ecosystem and, in this way, animals can develop health problems when exposed to high levels of pollutants. Reproductive failure and birth effects have been reported.

Eutrophication is occurring when elevated concentrations of nutrients (especially nitrogen) stimulate the blooming of aquatic algae, which can cause a disequilibration in the diversity of fish and their deaths.

Without a doubt, there is a critical concentration of pollution that an ecosystem can tolerate without being destroyed, which is associated with the ecosystem's capacity to neutralize acidity. The Canada Acid Rain Program established this load at 20 kg/ha/yr ( 120 ).

Hence, air pollution has deleterious effects on both soil and water ( 121 ). Concerning PM as an air pollutant, its impact on crop yield and food productivity has been reported. Its impact on watery bodies is associated with the survival of living organisms and fishes and their productivity potential ( 121 ).

An impairment in photosynthetic rhythm and metabolism is observed in plants exposed to the effects of ozone ( 121 ).

Sulfur and nitrogen oxides are involved in the formation of acid rain and are harmful to plants and marine organisms.

Last but not least, as mentioned above, the toxicity associated with lead and other metals is the main threat to our ecosystems (air, water, and soil) and living creatures ( 121 ).

In 2018, during the first WHO Global Conference on Air Pollution and Health, the WHO's General Director, Dr. Tedros Adhanom Ghebreyesus, called air pollution a “silent public health emergency” and “the new tobacco” ( 122 ).

Undoubtedly, children are particularly vulnerable to air pollution, especially during their development. Air pollution has adverse effects on our lives in many different respects.

Diseases associated with air pollution have not only an important economic impact but also a societal impact due to absences from productive work and school.

Despite the difficulty of eradicating the problem of anthropogenic environmental pollution, a successful solution could be envisaged as a tight collaboration of authorities, bodies, and doctors to regularize the situation. Governments should spread sufficient information and educate people and should involve professionals in these issues so as to control the emergence of the problem successfully.

Technologies to reduce air pollution at the source must be established and should be used in all industries and power plants. The Kyoto Protocol of 1997 set as a major target the reduction of GHG emissions to below 5% by 2012 ( 123 ). This was followed by the Copenhagen summit, 2009 ( 124 ), and then the Durban summit of 2011 ( 125 ), where it was decided to keep to the same line of action. The Kyoto protocol and the subsequent ones were ratified by many countries. Among the pioneers who adopted this important protocol for the world's environmental and climate “health” was China ( 3 ). As is known, China is a fast-developing economy and its GDP (Gross Domestic Product) is expected to be very high by 2050, which is defined as the year of dissolution of the protocol for the decrease in gas emissions.

A more recent international agreement of crucial importance for climate change is the Paris Agreement of 2015, issued by the UNFCCC (United Nations Climate Change Committee). This latest agreement was ratified by a plethora of UN (United Nations) countries as well as the countries of the European Union ( 126 ). In this vein, parties should promote actions and measures to enhance numerous aspects around the subject. Boosting education, training, public awareness, and public participation are some of the relevant actions for maximizing the opportunities to achieve the targets and goals on the crucial matter of climate change and environmental pollution ( 126 ). Without any doubt, technological improvements makes our world easier and it seems difficult to reduce the harmful impact caused by gas emissions, we could limit its use by seeking reliable approaches.

Synopsizing, a global prevention policy should be designed in order to combat anthropogenic air pollution as a complement to the correct handling of the adverse health effects associated with air pollution. Sustainable development practices should be applied, together with information coming from research in order to handle the problem effectively.

At this point, international cooperation in terms of research, development, administration policy, monitoring, and politics is vital for effective pollution control. Legislation concerning air pollution must be aligned and updated, and policy makers should propose the design of a powerful tool of environmental and health protection. As a result, the main proposal of this essay is that we should focus on fostering local structures to promote experience and practice and extrapolate these to the international level through developing effective policies for sustainable management of ecosystems.

Author Contributions

All authors listed have made a substantial, direct and intellectual contribution to the work, and approved it for publication.

Conflict of Interest

IM is employed by the company Delphis S.A. The remaining authors declare that the present review paper was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

Air Pollution

Our overview of indoor and outdoor air pollution.

By: Hannah Ritchie and Max Roser

This article was first published in October 2017 and last revised in February 2024.

Air pollution is one of the world's largest health and environmental problems. It develops in two contexts: indoor (household) air pollution and outdoor air pollution.

In this topic page, we look at the aggregate picture of air pollution – both indoor and outdoor. We also have dedicated topic pages that look in more depth at these subjects:

Indoor Air Pollution

Look in detail at the data and research on the health impacts of Indoor Air Pollution, attributed deaths, and its causes across the world

Outdoor Air Pollution

Look in detail at the data and research on exposure to Outdoor Air Pollution, its health impacts, and attributed deaths across the world

Look in detail at the data and research on energy consumption, its impacts around the world today, and how this has changed over time

See all interactive charts on Air Pollution ↓

Other research and writing on air pollution on Our World in Data:

• Air pollution: does it get worse before it gets better?
• Data Review: How many people die from air pollution?
• Energy poverty and indoor air pollution: a problem as old as humanity that we can end within our lifetime
• How many people do not have access to clean fuels for cooking?
• What are the safest and cleanest sources of energy?
• What the history of London’s air pollution can tell us about the future of today’s growing megacities
• When will countries phase out coal power?

Air pollution is one of the world's leading risk factors for death

Air pollution is responsible for millions of deaths each year.

Air pollution – the combination of outdoor and indoor particulate matter and ozone – is a risk factor for many of the leading causes of death, including heart disease, stroke, lower respiratory infections, lung cancer, diabetes, and chronic obstructive pulmonary disease (COPD).

The Institute for Health Metrics and Evaluation (IHME), in its Global Burden of Disease study, provides estimates of the number of deaths attributed to the range of risk factors for disease. 1

In the visualization, we see the number of deaths per year attributed to each risk factor. This chart shows the global total but can be explored for any country or region using the "change country" toggle.

Air pollution is one of the leading risk factors for death. In low-income countries, it is often very near the top of the list (or is the leading risk factor).

Air pollution contributes to one in ten deaths globally

In recent years, air pollution has contributed to one in ten deaths globally. 2

In the map shown here, we see the share of deaths attributed to air pollution across the world.

Air pollution is one of the leading risk factors for disease burden

Air pollution is one of the leading risk factors for death. But its impacts go even further; it is also one of the main contributors to the global disease burden.

Global disease burden takes into account not only years of life lost to early death but also the number of years lived in poor health.

In the visualization, we see risk factors ranked in order of DALYs – disability-adjusted life years – the metric used to assess disease burden. Again, air pollution is near the top of the list, making it one of the leading risk factors for poor health across the world.

Air pollution not only takes years from people's lives but also has a large effect on the quality of life while they're still living.

Who is most affected by air pollution?

Death rates from air pollution are highest in low-to-middle-income countries.

Air pollution is a health and environmental issue across all countries of the world but with large differences in severity.

In the interactive map, we show death rates from air pollution across the world, measured as the number of deaths per 100,000 people in a given country or region.

The burden of air pollution tends to be greater across both low and middle-income countries for two reasons: indoor pollution rates tend to be high in low-income countries due to a reliance on solid fuels for cooking, and outdoor air pollution tends to increase as countries industrialize and shift from low to middle incomes.

A map of the number of deaths from air pollution by country can be found here .

How are death rates from air pollution changing?

Death rates from air pollution are falling – mainly due to improvements in indoor pollution.

In the visualization, we show global death rates from air pollution over time – shown as the total air pollution – in addition to the individual contributions from outdoor and indoor pollution.

Globally, we see that in recent decades, the death rates from total air pollution have declined: since 1990, death rates have nearly halved. But, as we see from the breakdown, this decline has been primarily driven by improvements in indoor air pollution.

Death rates from indoor air pollution have seen an impressive decline, while improvements in outdoor pollution have been much more modest.

You can explore this data for any country or region using the "change country" toggle on the interactive chart.

Interactive charts on air pollution

Murray, C. J., Aravkin, A. Y., Zheng, P., Abbafati, C., Abbas, K. M., Abbasi-Kangevari, M., ... & Borzouei, S. (2020). Global burden of 87 risk factors in 204 countries and territories, 1990–2019: a systematic analysis for the Global Burden of Disease Study 2019 .  The Lancet ,  396 (10258), 1223-1249.

Here, we use the term 'contributes,' meaning it was one of the attributed risk factors for a given disease or cause of death. There can be multiple risk factors for a given disease that can amplify one another. This means that in some cases, air pollution was not the only risk factor but one of several.

Cite this work

Our articles and data visualizations rely on work from many different people and organizations. When citing this topic page, please also cite the underlying data sources. This topic page can be cited as:

BibTeX citation

Reuse this work freely

All visualizations, data, and code produced by Our World in Data are completely open access under the Creative Commons BY license . You have the permission to use, distribute, and reproduce these in any medium, provided the source and authors are credited.

The data produced by third parties and made available by Our World in Data is subject to the license terms from the original third-party authors. We will always indicate the original source of the data in our documentation, so you should always check the license of any such third-party data before use and redistribution.

All of our charts can be embedded in any site.

Our World in Data is free and accessible for everyone.

Help us do this work by making a donation.

Essay on Air Pollution in English 100, 200, 300, And 500 Words

Essay on air pollution in English: Dive into a world where the air we breathe is not as pure as it seems. India, our beloved land, faces a hidden adversary: air pollution. This invisible foe affects millions, altering our health and environment. Through understanding its causes and impacts, we can unite to combat it. Join us on this enlightening journey, and let’s clear the air together.

In this article, we have provided 100, 200, 300, and 500-word air pollution essays.

Essay on Air Pollution in 100 Words

Imagine a world where the sky is no longer blue. Air pollution is turning our skies grey. It’s a problem we all face, affecting our health and planet.

Air pollution comes from many sources like cars, factories, and even our homes. Tiny particles and gases mix with the air, making it dirty. This dirty air can make us sick, causing problems like asthma and heart disease. Animals and plants suffer too, with their habitats becoming polluted. Clean air is essential for all living things on Earth to thrive and stay healthy.

Air pollution is a serious issue. It’s up to us to make changes. Together, we can clean the air for a brighter, healthier tomorrow.

Essay on Air Pollution in 200 Words

Imagine waking up to a gray sky, where the air is thick with smog. This is not a scene from a dystopian novel but the reality of air pollution in many cities today. Air pollution poses a grave threat to our health and the environment, making it an issue that cannot be ignored.

Air pollution consists of harmful substances released into the air, primarily by human activities. These include gases like carbon dioxide, which contributes to global warming, and particulate matter, which can penetrate our lungs, causing respiratory issues. Vehicles, industries, and even agricultural practices contribute to this menace. The effects are alarming, leading to health problems such as asthma, heart disease, and even premature death. Moreover, air pollution damages ecosystems, affecting water quality and wildlife. It also impacts climate patterns globally, leading to unpredictable weather. The visibility of landmarks and the beauty of our cities are marred by the haze of pollutants, affecting tourism and daily life.

The air we breathe is turning into a poison. It’s high time we take concerted action to tackle this issue. Reducing pollution requires collective effort and significant changes in our lifestyle and policies.

Essay on Air Pollution in 300 Words

Air pollution, a dire environmental crisis, is not a distant threat but a current global challenge. It indiscriminately affects every corner of the globe, from the most bustling urban cities to the most serene rural countryside. Understanding and confronting this menace is an urgent necessity. We must act swiftly to mitigate its impact.

Air pollution comprises various harmful substances released into our atmosphere. Numerous sources contribute to this pervasive issue, including industrial factories, vehicles on our roads, agricultural activities, and widespread deforestation. These pollutants, often invisible to the naked eye, deceive us into believing the air we breathe is clean. In reality, they pose severe health risks to humans and animals alike. Conditions such as respiratory infections, heart disease, and even premature death have been directly linked to air pollution exposure. Vulnerable populations, particularly children and the elderly, are disproportionately affected. Beyond human health, wildlife and natural ecosystems also suffer significant harm, disrupting the delicate balance of our natural world.

Pollution knows no borders, spreading its toxic reach across countries and continents, underscoring the need for a unified global response. In areas heavily burdened by pollution, clean air has become a rare, luxury commodity. Initiatives to curb emissions and reduce pollution are in motion, but the scale of action remains insufficient. Transitioning to renewable energy sources, enforcing stricter environmental regulations, and promoting sustainable practices are critical steps forward. Everyone, from governments to individuals, holds a stake in this fight against air pollution. By making informed choices and small changes in our daily lives, we can contribute to a larger, positive impact.

Confronting air pollution is an immense challenge, yet it is not beyond our collective capability to overcome it. By fostering awareness, encouraging proactive action, and facilitating global cooperation, we can pave the way toward a cleaner, healthier future. The air we breathe is fundamental to life; safeguarding its purity is a responsibility we all share.

Essay on Air Pollution in 500 Words

Imagine a world where every breath you take is a challenge. This is not a scene from a dystopian movie but a harsh reality in many parts of our planet due to air pollution. Air, a vital element for all living beings, is becoming a cocktail of poisonous gases. The sky, once clear and blue, now often wears a blanket of smog. This situation is alarming and demands our immediate attention.

Air pollution happens when harmful substances mix with the air we breathe. This can include gases like carbon dioxide from cars and factories, smoke from burning trash, and tiny particles from construction sites. Even natural events like forest fires or volcanic eruptions can add to air pollution. These pollutants can harm our health, making it hard to breathe, and hurt the environment by harming plants and animals. Everyone needs to help reduce air pollution by using less energy.

Air pollution has several harmful effects on both our health and the environment. Firstly, it can cause respiratory problems like asthma and bronchitis, as it makes the air we breathe dirty with chemicals and particles. Secondly, it can lead to heart disease because pollutants can enter our bloodstream through the lungs. Thirdly, air pollution affects wildlife and plants, making it hard for them to survive in their natural habitats. It also contributes to climate change by increasing the amount of greenhouse gases in the atmosphere, leading to global warming. Lastly, it can cause acid rain, which harms trees, soils, and water bodies

Types of air pollution:

• 1. Particulate Matter (PM): Tiny particles or droplets in the air, like dust, soot, and smoke. They can harm our lungs and heart.
• 2. Nitrogen Oxides (NOx): Gases that come mostly from car exhausts and power plants. They can make the air hazy and form smog.
• 3. Sulfur Dioxide (SO2): A gas from burning fossil fuels like coal. It can cause acid rain, which harms plants, animals, and buildings.
• 4. Carbon Monoxide (CO): A colorless, odorless gas from burning things like wood and gasoline. It’s harmful because it can block oxygen from getting into our bodies.
• 5. Ozone (O3): A gas that’s good high up in the atmosphere but harmful at ground level, causing smog and respiratory problems.
• 6. Volatile Organic Compounds (VOCs): Chemicals from paints, cleaners, and gasoline. They can cause smog and health issues.

Air Pollution Reduction Steps:

Plant More Trees: Trees absorb carbon dioxide and release oxygen. Planting more trees helps clean the air.

• Use Public Transport: Cars produce a lot of pollution. Using buses, trains, or carpooling reduces the number of vehicles on the road.
• Recycle and Reuse: Producing new things causes pollution. By recycling and reusing, we reduce waste and pollution.
• Save Energy: Turn off lights and electronics when not in use. Using less energy reduces pollution from power plants.
• Educate Others: Share what you know about air pollution and its solutions with friends and family to spread awareness.

Related post:

• Air pollution paragraph
• 10 Lines air pollution

Air pollution is a daunting challenge, but it is not insurmountable. Awareness and action can lead us to a cleaner, healthier future. Together, we can clear the air.

Similar Posts

A rainy day essay in 100, 200, 300, and 500 words.

A rainy day essay: On a day shrouded in clouds, the skies weep, heralding a transformation. Streets become rivulets; trees dance in the rain’s melody. This spectacle, a common marvel…

A Journey by Train Essay in 100, 200, 300, and 500 Words

A journey by train essay: Embarking on a train journey unfolds a tapestry of landscapes, emotions, and unexpected encounters. It’s a voyage where time slows, hearts connect, and the world…

A Good Teacher Essay in 100, 200, 300, and 500 Words

A good teacher: A good teacher doesn’t just educate; they inspire. With wisdom and patience, they transform the mundane into the extraordinary. Their lessons go beyond textbooks, igniting curiosity and…

Winter Morning Essay in 100, 200, 300, And 500 Words

Winter morning essay: Winter mornings whisper tales of frosty silence, awakening the world in a chilly embrace. As dawn breaks, nature adorns itself with a sparkling gown, inviting us into…

A Firefighter Essay in 100, 200, 300, and 500 Words

Embarking on a journey through flames, firefighters epitomize bravery. These guardians against disaster risk everything to save lives. Their heroism, veiled in soot and sweat, speaks volumes. Dive into their…

A Tea Stall Essay in 100, 200, 300, And 500 Words

A tea stall essay: If you wander through the bustling streets of your town. Suddenly, the aromatic allure of tea calls you. Nestled among the hustle and bustle, a small…

Leave a Reply Cancel reply

Your email address will not be published. Required fields are marked *

Save my name, email, and website in this browser for the next time I comment.

Talk to our experts

1800-120-456-456

• Air Pollution Essay

Essay on Air Pollution

Environmental changes are caused by the natural or artificial content of harmful pollutants and can cause instability, disturbance, or adverse effects on the ecosystem. Earth and its environment pose a more serious threat due to the increasing pollution of air, water, and soil. Environmental damage is caused by improper resource management or careless human activities. Therefore, any activity that violates the original nature of the environment and leads to degradation is called pollution. We need to understand the origin of these pollutants and find ways to control pollution. This can also be done by raising awareness of the effects of pollutants.

Air pollution is any physical, chemical, or biological change in the air. A certain percentage of the gas is present in the atmosphere. Increasing or decreasing the composition of these gasses is detrimental to survival. This imbalance in gas composition causes an increase in global temperature which is called global warming.

Introduction to air pollution 

The Earth and its environment are facing a serious threat by the increasing pollution of the air, water, and soil—the vital life support systems of the Earth. The damage to the environment is caused by improper management of resources or by careless human activity. Hence any activity that violates the original character of nature and leads to its degradation is called pollution. We need to understand the sources of these pollutants and find ways to control pollution. This can be also done by making people aware of the effects of pollutants. 

Air with 78% Nitrogen, 21% Oxygen, and 1% of all other gasses support life on Earth. Various processes take place to sustain the regular percentage of gasses and their composition in general. 

Atmospheric pollution can have natural sources, for example, volcanic eruptions. The gaseous by-products of man-made processes such as energy production, waste incineration, transport, deforestation and agriculture, are the major air pollutants.

Although air is made up of mostly Oxygen and Nitrogen, mankind, through pollution, has increased the levels of many trace gasses, and in some cases, released completely new gasses to the atmosphere. 

Air pollution can result in poor air quality, both in cities and in the countryside. Some air pollutants make people sick, causing breathing problems and increasing the likelihood of cancer. 

Some air pollutants are harmful to plants, animals, and the ecosystems in which they live. Statues, monuments, and buildings are being corroded by the air pollutants in the form of acid rain. It also damages crops and forests, and makes lakes and streams unsuitable for fish and other plant and animal life. 

Air pollution created by man-made resources is also changing the Earth’s atmosphere. It is causing the depletion of the ozone layer and letting in more harmful radiation from the Sun. The greenhouse gasses released into the atmosphere prevents heat from escaping back into space and leads to a rise in global average temperatures. Global warming affects the average sea-level and increases the spread of tropical diseases.

Air pollution occurs when large amounts of gas and tiny particles are released into the air and the ecological balance is disturbed. Each year millions of tons of gasses and particulate matter are emitted into the air. 

Primary air pollutants are pollutants, which are directly released into the air. They are called SPM, i.e., Suspended Particulate Matter. For example, smoke, dust, ash, sulfur oxide, nitrogen oxide, and radioactive compounds, etc.

Secondary Pollutants are pollutants, which are formed due to chemical interactions between the atmospheric components and primary pollutants. For example, Smog (i.e. Smoke and fog), ozone, etc.

Major gaseous air pollutants include Carbon Dioxide, Hydrogen Sulfide, Sulfur Dioxide and Nitrogen Oxide, etc.

Natural sources are volcanic eruptions, forest fires, dust storms, etc. 

Man-made sources include gasses released from the automobiles, industries, burning of garbage and bricks kilns, etc.

Effects of Air Pollution on Human Health

Air pollution has adverse effects on human health. 

Breathing polluted air puts you at higher risk of asthma.

When exposed to ground ozone for 6 to 7 hours, people suffer from respiratory inflammation.

Damages the immune system, endocrine, and reproductive systems.

A high level of air pollution has been associated with higher incidents of heart problems.

The toxic chemicals released into the air are affecting the flora and fauna immensely.

Preventive Measures to Reduce Air Pollution

We can prevent pollution by utilizing raw materials, water energy, and other resources more efficiently. When less harmful substances are substituted for hazardous ones, and when toxic substances are eliminated from the production process, human health can be protected and economic wellbeing can be strengthened. 

There are several measures that can be adopted by people to reduce pollution and to save the environment.

Carpooling.

Promotion of public transport.

No smoking zone.

Restricted use of fossil fuels.

Saving energy.

Encouraging organic farming.

The government has put restrictions on the amount of fossil fuels that can be used as well as restrictions on how much carbon dioxide and other pollutants can be emitted. Although the government is attempting to save our environment from these harmful gasses, it is not sufficient. We as a society need to keep the environment clean by controlling the pollution of air.

FAQs on Air Pollution Essay

1. State the Causes of Air Pollution ?

The following are the causes of air pollution.

Vehicular pollution consisting of Carbon Monoxide causes pollution.

Emission of Nitrogen oxide by a large number of supersonic transport airplanes causes deterioration of the Ozone layer and also causes serious damage to the flora and fauna.

The release of Chlorofluorocarbons into the Stratosphere causes depletion of Ozone, which is a serious concern to animals, microscopic, and aquatic organisms.

Burning garbage causes smoke, which pollutes the atmosphere. This smoke contains harmful gases such as Carbon dioxide and Nitrogen oxides.

In India, brick kilns are used for many purposes and coal is used to burn the bricks. They give out huge quantities of Carbon dioxide and particulate matter such as smoke, dust that are very harmful to people working there and the areas surrounding it. 

Many cleansing agents release poisonous gases such as Ammonia and Chlorine into the atmosphere. 

Radioactive elements emit harmful rays into the air.

Decomposed animals and plants emit Methane and Ammonia gas into the air.

2. What Does Global Warming Mean?

Global warming is the gradual rising average temperature of the Earth's atmosphere due to the concentration of methane in certain toxic gasses such as carbon dioxide. This has a major impact on the world climate. The world is warming. The land and the sea are now warmer than they were at the beginning and temperatures are still rising. This rise in temperature is, in short, global warming. This temperature rise is man-made. The burning of fossil fuels releases greenhouse gasses into the atmosphere which capture solar heat and raise surface and air temperatures.

3. Name the Alternative Modes of Transport. In What Way Does it Help to Reduce Air Pollution?

Public transport could be an alternative mode of transport. Public transport like trains, buses and trams, can relieve traffic congestion and reduce air pollution from road transport. The use of public transport must be encouraged in order to develop a sustainable transport policy.

4. Mention other means of transportation! How can I help reduce air pollution?

Public transportation can be another mode of transportation. Public transport such as trains, buses and trams can reduce traffic congestion and reduce air pollution from road transport. The use of public transport and to develop sustainable transport policies should be encouraged. While one passenger vehicle has the convenience factor, other modes of transportation reduce travel costs, spend less time, reduce stress, improve health, and reduce energy consumption and parking. Other trips for work include walking/cycling, public transport, hybrid travel and transport.

5. What are the effects of pollution?

Excessive air pollution can increase the risk of heart attack, wheezing, coughing and difficulty breathing, as well as irritation of the eyes, nose and throat. Air pollution can also cause heart problems, asthma, and other lung problems. Due to the emission of greenhouse gases, the composition of the air in the air is disturbed. This causes an increase in global temperature. The damaging ozone layer due to air pollution does not prevent harmful ultraviolet rays from the sun, which cause skin and eye problems in individuals. Air pollution has caused a number of respiratory and heart diseases among people. The incidence of lung cancer has increased in recent decades. Children living in contaminated areas are more likely to develop pneumonia and asthma. Many people die every year due to the direct or indirect effects of air pollution. When burning fossil fuels, harmful gases such as nitrogen oxides and sulfur oxides are released into the air. Water droplets combine with these pollutants and become acidic and fall as acid rain, which harms human, animal and plant life.

6. What is the solution to air pollution?

Production of renewable fuels and clean energy. The basic solution to air pollution is to get away from fossil fuels and replace them with other energies such as solar, wind and geothermal. The government limits the amount of fossil fuel that can be used and how much carbon dioxide and other pollutants it can emit. While the government is trying to save our environment from this harmful gas, it is not enough. We as a society need to keep the environment clean by controlling air pollution. To more in detail about air pollution and its causes. To learn more about air pollution and its impact on the environment, visit the Vedantu website.

Does air pollution—specifically tiny atmospheric particles (aerosols)—affect global warming?

Published May 13, 2009 Updated Aug 23, 2016

Air pollution occurs when the air contains gases, dust, smoke from fires, or fumes in harmful amounts. Tiny atmospheric particles - aerosols - are a subset of air pollution that are suspended in our atmosphere.

Aerosol can be both solid and liquid. Most are produced by natural processes such as erupting volcanoes, and some are from human industrial and agricultural activities.

Aerosols have a measurable effect on climate change . Light-colored aerosol particles can reflect incoming energy from the sun in cloud-free air and dark particles can absorb it. Over the historic period, the net effect globally was for aerosols to partially offset the rise in global mean surface temperature. Aerosols can modify how much energy clouds reflect and they can change atmospheric circulation patterns.

Aerosol sources, composition, and removal processes

Worldwide, most atmospheric aerosol particles are produced by natural processes such as grinding and erosion of land surfaces resulting in dust, salt-spray formation in oceanic breaking waves, biological decay, forest fires, chemical reactions of atmospheric gases, and volcanic injection .

Some particles, on the other hand, have human origins—industry, agriculture, transport (including aviation), and construction. The composition of atmospheric aerosol particles varies widely depending on their source—they may contain salts (predominantly sulfates), minerals (such as silicon), organic materials, and, in most cases, water. 

The particles grow by absorbing water vapor and other gases. In moist air, clouds form when water vapor condenses onto these ‘cloud condensation nuclei’. These then grow into cloud drops, which eventually fall to the surface as rain or snow, depositing the particles on land or in the ocean.

Although dust plumes from the Sahara and Gobi deserts can be seen circling most of the globe in satellite pictures, aerosol particles in the lower troposphere (the lowest layer of the atmosphere, where weather occurs) are usually removed from the atmosphere by settling and precipitation within several days to weeks after they were produced. In the stratosphere (the atmosphere layer above the troposphere), chemical reactions of gases from volcanoes produce sulfate particles that can remain for one or more years, spreading over much of the globe.

Aerosol particles and climate

Although we are familiar with local particulate ‘air pollution’ due to human activities, the fact that atmospheric particles of both natural and human origin have substantial influence on our climate is less widely understood. The particles can play important climatic roles both outside and inside clouds.

In clear air, tiny aerosol particles interact with the solar beam. Particles containing little or no carbon are effectively ‘white.’ They reflect solar radiation, making the air and Earth surface below them a bit cooler than they would otherwise be. Sulfate particles in the stratosphere from the Pinatubo volcanic eruption in 1991, for example, produced measurable cooling for two years over much of the globe. In contrast, particles containing substantial amounts of black carbon (e. g., soot, which is typically produced from combustion of fossil fuels, biofuels, and biomass burning) warm their surroundings by absorbing solar radiation before it reaches the ground. Since black carbon reflects the incoming sunlight, it also acts a shade and the ground surface below becomes cooler .

These tiny particles also create cloud droplets in the lower troposphere. Water droplets and ice particles are basically white, so they reflect solar radiation; on the other hand, the condensed water also traps and emits long wave radiation, producing heat. Thus clouds can have either cooling or warming effects on a local area, depending on the altitude of the cloud and whether the reflecting or trapping effect is strongest.

Because of many unknowns relating to aerosol particles, the magnitude of aerosol impacts is one of the major advancements in understanding that occurred between the fourth and fifth IPCC climate assessments . Particularly noteworthy is the higher confidence regarding aerosol radiation interactions and volcanic aerosols. NASA currently has several aerosol monitoring sites across the world , whose data are used for better understanding of climate and air quality, and for better pollution management.

How is human-caused air pollution changing our climate?

Human-caused particulate air pollution has a relatively minor—and likely decreasing—impact on our climate. 

Aerosol particles of human origin can have a net effect of diminishing the energy that arrives at the Earth’s surface. Scientists estimate that particles produced by human activities have led to a net loss of solar energy (heat) at the ground by as much as 8 percent in densely populated areas over the past few decades. This effect, sometimes referred to as ‘ solar dimming ,’ may have masked some of the late 20th century global warming due to heat-trapping gases.

Human activities that result in production of both reflecting and absorbing aerosol particle have been curtailed by legislation and modern technology in many places. The ‘pea soup fogs’ that so bedeviled London in Sherlock Holmes’ day, for example, were caused by particles produced by incomplete combustion of coal for heating. These ‘fogs’ in London are now a thing of the past , thanks to mandatory scrubbers and other advanced combustion techniques.

Regional and temporal aerosols trends indicate shifts in regions of influence for aerosols produced from human activities. Haze clouds seen over urban regions give dramatic proof of the effects of human-induced particles in the United States, while atmospheric soot production from burning fossil fuels for energy production is still very high in many parts of Asia, including large clouds of pollution across much of China.

The primary cause of global warming is too much CO2

Global warming is primarily caused by emissions of too much carbon dioxide (CO2) and other heat-trapping gases into the atmosphere when we burn fossil fuels to generate electricity, drive our cars, and power our lives.

These heat-trapping gases spread worldwide and remain in the atmosphere for decades to centuries. Thus, as we continue to emit these gases, their atmospheric concentrations build up over time. In contrast, atmospheric aerosol particles are largely localized near their sources, and do not linger in the atmosphere for long so that, even if we continue to emit them at current rates, their atmospheric concentrations will not build up markedly over time.

The effect of long-lived global warming emissions will far outweigh the cooling effect of short-lived atmospheric particles.

Can climate intervention with aerosols save us from global warming?

Because global warming is such a serious threat, some scientists and engineers have explored the idea of harnessing the reflective power of some aerosol particles to temporarily combat global warming while non fossil fuel energy sources are being more fully developed . Several climate intervention (also-called ‘geoengineering’) strategies for reducing global warming propose using atmospheric aerosol particles to reflect the sun’s energy away from Earth.

The idea is to artificially increase the concentrations of ‘white’ atmospheric aerosol particles above the surface of the ocean and/or in the lower stratosphere (above where weather occurs) in order to reflect more of the sun’s energy away from Earth. The field of climate intervention (still in its infancy), has the potential to buy us some time in the attempt to maintain relatively slow warming rates. Such actions would have large hurdles regarding international governance, and experimentation with our very complex climate system by dramatically increasing reflecting aerosols carries with it the potential for large unintended, and potentially dangerous, side effects on ecosystems, agriculture, and human health. Therefore, any intentional increase in aerosol particles would have to be considered carefully and thoroughly before a possible deployment.

Foremost, because aerosol particles do not stay in the atmosphere for very long—and global warming gases stay in the atmosphere for decades to centuries—accumulated heat-trapping gases will overpower any temporary cooling due to short-lived aerosol particles. Climate intervention  is not considered a replacement  for the reduction of carbon emissions.

Related resources

Research Areas for Climate Litigation

Water, Water Every Where

Looming Deadlines for Coastal Resilience

Follow the Money

We use cookies to improve your experience. By continuing, you accept our use of cookies. Learn more .

Support our work

Other ways to give.

• Honor & memory
• Become a member
• Give monthly
• Make a planned gift
• Gift memberships

Your donation at work

Essay on How to Reduce Air Pollution

Students are often asked to write an essay on How to Reduce Air Pollution in their schools and colleges. And if you’re also looking for the same, we have created 100-word, 250-word, and 500-word essays on the topic.

Let’s take a look…

100 Words Essay on How to Reduce Air Pollution

Understanding air pollution.

Air pollution is harmful substances in the air. It harms our health and the environment. It’s mainly caused by human activities like burning fossil fuels.

Ways to Reduce Air Pollution

1. Use Public Transport: Using buses, trains, or carpooling reduces the number of vehicles on the road, reducing air pollution. 2. Save Energy: By turning off lights and electronics when not in use, we save energy and reduce pollution. 3. Plant Trees: Trees absorb harmful pollutants and release clean oxygen. 4. Recycle: Recycling reduces the need to burn waste, reducing air pollution.

Remember, every small action counts in fighting air pollution.

Also check:

250 Words Essay on How to Reduce Air Pollution

Understanding the gravity of air pollution, adopting sustainable transportation.

A significant contributor to air pollution is vehicular emissions. To address this, we must shift towards sustainable modes of transportation. Encouraging public transit, carpooling, biking, or walking can significantly reduce the number of vehicles on the road, thus curbing pollution. Additionally, promoting electric vehicles can help eliminate exhaust emissions.

Embracing Renewable Energy

The energy sector, particularly coal-based power plants, significantly contributes to air pollution. Transitioning to renewable energy sources such as solar, wind, and hydroelectric power can significantly reduce air pollution. These energy sources are not only sustainable but also emit no pollutants, making them an ideal replacement for fossil fuels.

Improving Waste Management

Improper waste disposal, especially burning, releases harmful pollutants into the air. Implementing effective waste management strategies, such as recycling and composting, can minimize waste burning. Additionally, promoting waste-to-energy technologies can help transform waste into useful energy while reducing pollution.

Enforcing Strict Regulations

Governmental bodies must enforce stringent air quality standards and regulations. Strict penalties for non-compliance can deter potential polluters, ensuring cleaner air.

500 Words Essay on How to Reduce Air Pollution

Introduction.

Air pollution is a pressing issue that threatens the health of our planet and its inhabitants. It is primarily caused by harmful gases and particles released into the atmosphere, mostly from human activities. Addressing this problem requires a multi-faceted approach, involving both individual and collective actions.

One of the primary sources of air pollution is vehicular emissions. As such, it is crucial to promote sustainable transportation methods. Individuals can contribute to reducing air pollution by utilizing public transport, cycling, walking, or carpooling. On a larger scale, governments and corporations can invest in infrastructure for electric vehicles and renewable fuels, which produce fewer emissions than traditional fossil fuels.

Energy Conservation and Efficiency

Energy production, particularly through burning fossil fuels, significantly contributes to air pollution. Therefore, energy conservation is an effective strategy to combat this issue. This can be achieved by using energy-efficient appliances, reducing energy usage, and promoting renewable energy sources. On an institutional level, energy producers can transition to cleaner technologies, such as wind, solar, and hydroelectric power.

Waste Management

Improper waste disposal, including open burning of waste, contributes to air pollution. Therefore, effective waste management strategies are essential. This includes recycling, composting, and reducing waste production. On a larger scale, governments can implement policies to regulate waste disposal and encourage recycling.

Legislative Actions

Governments play a crucial role in air pollution reduction by enforcing regulations that limit emissions from various sources. This includes setting stringent standards for industries and vehicles, promoting clean energy, and implementing pollution-control laws. Governments can also incentivize businesses to adopt environmentally friendly practices through tax benefits and subsidies.

Public Awareness and Education

Air pollution is a complex issue that requires a comprehensive, multi-pronged approach to address effectively. While individual actions are important, large-scale changes driven by governments and corporations are crucial. Through the combined efforts of individuals, governments, and businesses, we can work towards a future with cleaner air and a healthier planet. It is not just a matter of environmental concern but a significant health and economic issue that, if unchecked, will have far-reaching consequences for future generations. Hence, it is our collective responsibility to reduce air pollution and safeguard our planet.

That’s it! I hope the essay helped you.

Apart from these, you can look at all the essays by clicking here .

Happy studying!

Leave a Reply Cancel reply

Your email address will not be published. Required fields are marked *

Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

• View all journals
• Explore content
• About the journal
• Publish with us
• Sign up for alerts
• Open access
• Published: 17 June 2020

Half the world’s population are exposed to increasing air pollution

• G. Shaddick   ORCID: orcid.org/0000-0002-4117-4264 1 ,
• M. L. Thomas 2 ,
• P. Mudu 3 ,
• G. Ruggeri 3 &
• S. Gumy 3  

npj Climate and Atmospheric Science volume  3 , Article number:  23 ( 2020 ) Cite this article

48k Accesses

230 Citations

508 Altmetric

Metrics details

• Environmental impact

Air pollution is high on the global agenda and is widely recognised as a threat to both public health and economic progress. The World Health Organization (WHO) estimates that 4.2 million deaths annually can be attributed to outdoor air pollution. Recently, there have been major advances in methods that allow the quantification of air pollution-related indicators to track progress towards the Sustainable Development Goals and that expand the evidence base of the impacts of air pollution on health. Despite efforts to reduce air pollution in many countries there are regions, notably Central and Southern Asia and Sub-Saharan Africa, in which populations continue to be exposed to increasing levels of air pollution. The majority of the world’s population continue to be exposed to levels of air pollution substantially above WHO Air Quality Guidelines and, as such, air pollution constitutes a major, and in many areas, increasing threat to public health.

Similar content being viewed by others

Environmental determinants of cardiovascular disease: lessons learned from air pollution

Global air pollution exposure and poverty

Disparities in air pollution attributable mortality in the US population by race/ethnicity and sociodemographic factors

Introduction.

In 2016, the WHO estimated that 4.2 million deaths annually could be attributed to ambient (outdoor) fine particulate matter air pollution, or PM 2.5 (particles smaller than 2.5 μm in diameter) 1 . PM 2.5 comes from a wide range of sources, including energy production, households, industry, transport, waste, agriculture, desert dust and forest fires and particles can travel in the atmosphere for hundreds of kilometres and their chemical and physical characteristics may vary greatly over time and space. The WHO developed Air Quality Guidelines (AQG) to offer guidance for reducing the health impacts of air pollution. The first edition, the WHO AQG for Europe, was published in 1987 with a global update (in 2005) reflecting the increased scientific evidence of the health risks of air pollution worldwide and the growing appreciation of the global scale of the problem 2 . The current WHO AQG states that annual mean concentration should not exceed 10 μg/m 3  2 .

The adoption and implementation of policy interventions have proved to be effective in improving air quality 3 , 4 , 5 , 6 , 7 . There are at least three examples of enforcement of long-term policies that have reduced concentration of air pollutants in Europe and North America: (i) the Clean Air Act in 1963 and its subsequent amendments in the USA; (ii) the Convention on Long-range Transboundary Air Pollution (LRTAP) with protocols enforced since the beginning of the 1980s in Europe and North America 8 ; and (iii) the European emission standards passed in the European Union in the early 1990s 9 . However, between 1960 and 2009 concentrations of PM 2.5 globally increased by 38%, due in large part to increases in China and India, with deaths attributable to air pollution increasing by 124% between 1960 and 2009 10 .

The momentum behind the air pollution and climate change agendas, and the synergies between them, together with the Sustainable Development Goals (SDGs) provide an opportunity to address air pollution and the related burden of disease. Here, trends in global air quality between 2010 and 2016 are examined in the context of attempts to reduce air pollution, both through long-term policies and more recent attempts to reduce levels of air pollution. Particular focus is given to providing comprehensive coverage of estimated concentrations and obtaining (national-level) distributions of population exposures for health impact assessment. Traditionally, the primary source of information has been measurements from ground monitoring networks but, although coverage is increasing, there remain regions in which monitoring is sparse, or even non-existent (see Supplementary Information) 11 . The Data Integration Model for Air Quality (DIMAQ) was developed by the WHO Data Integration Task Force (see Acknowledgements for details) to respond to the need for improved estimates of exposures to PM 2.5 at high spatial resolution (0.1° × 0.1°) globally 11 . DIMAQ calibrates ground monitoring data with information from satellite retrievals of aerosol optical depth, chemical transport models and other sources to provide yearly air quality profiles for individual countries, regions and globally 11 . Estimates of PM 2.5 concentrations have been compared with previous studies and a good quantitative agreement in the direction and magnitude of trends has been found. This is especially valid in data rich settings (North America, Western Europe and China) where trends results are consistent with what has been found from the analysis of ground level PM 2.5 measurements.

Figure 1a shows average annual concentrations of PM 2.5 for 2016, estimated using DIMAQ,; and Fig. 1b the differences in concentrations between 2010 and 2016. Although air pollution affects high and low-income countries alike, low- and middle-income countries experience the highest burden, with the highest concentrations being seen in Central, Eastern Southern and South-Eastern Asia 12 .

a Concentrations in 2016. b Changes in concentrations between 2010 and 2016.

The high concentrations observed across parts of the Middle East, parts of Asia and Sub-Saharan regions of Africa are associated with sand and desert dust. Desert dust has received increasing attention due to the magnitude of its concentration and the capacity to be transported over very long distances in particular areas of the world 13 , 14 . The Sahara is one of the biggest global source of desert dust 15 and the increase of PM 2.5 in this region is consistent with the prediction of an increase of desert dust due to climate change 16 , 17 .

Globally, 55.3% of the world’s population were exposed to increased levels of PM 2.5 , between 2010 and 2016, however there are marked differences in the direction and magnitude of trends across the world. For example, in North America and Europe annual average population-weighted concentrations decreased from 12.4 to 9.8 μg/m 3 while in Central and Southern Asia they rose from 54.8 to 61.5 μg/m 3 . Reductions in concentrations observed in North America and Europe align with those reported by the US Environmental Protection Agency and European Environmental Agency (EEA) 18 , 19 . The lower values observed in these regions reflect substantial regulatory processes that were implemented thirty years ago that have led to substantial decreases in air pollution over previous decades 18 , 20 , 21 . In high-income countries, the extent of air pollution from widespread coal and other solid-fuel burning, together with other toxic emissions from largely unregulated industrial processes, declined markedly with Clean Air Acts and similar ‘smoke control’ legislation introduced from the mid-20th century. However, these remain important sources of air pollution in other parts of the world 22 . In North America and Europe, the rates of improvements are small reflecting the difficulties in reducing concentrations at lower levels.

Assessing the health impacts of air pollution requires detailed information of the levels to which specific populations are exposed. Specifically, it is important to identify whether areas where there are high concentrations are co-located with high populations within a country or region. Population-weighted concentrations, often referred to as population-weighted exposures, are calculated by spatially aligning concentrations of PM 2.5 with population estimates (see Supplementary Information).

Figure 2 shows global trends in estimated concentrations and population-weighted concentrations of PM 2.5 for 2010–2016, together with trends for SDG regions (see Supplementary Fig. 1.1 ). Where population-weighted exposures are higher than concentrations, as seen in Central Asia and Southern Asia, this indicates that higher levels of air pollution coincide with highly populated areas. Globally, whilst concentrations have reduced slightly (from 12.8 μg/m 3 in 2010 to 11.7 in 2016), population-weighted concentrations have increased slightly (33.5 μg/m 3 in 2010, 34.6 μg/m 3 in 2016). In North America and Europe both concentrations and population-weighted concentrations have decreased (6.1–4.9 and 12.4–9.8 μg/m 3 , respectively). The association between concentrations and population can be clearly seen for Central Asia and Southern Asia where concentrations increased from 29.6 to 31.7 μg/m 3 (a 7% increase) while population-weighted concentrations were higher both in magnitude and in percentage of increase, increasing from 54.8 to 61.5 μg/m 3 (a 12% increase).

a Concentrations. b Population-weighted concentrations.

For the Eastern Asia and South Eastern Asia concentrations increase from 2010 to 2013 and then decrease from 2013 to 2016, a result of the implementation of the ‘Air Pollution Prevention and Control Action Plan’ 21 and the transition to cleaner energy mix due to increased urbanization in China 23 , 24 , 25 . Population-weighted concentrations for urban areas in this region are strongly influenced by China, which comprises 62.6% of the population in the region. Population-weighted concentrations are higher than the concentrations and the decrease is more marked (in the population-weighted concentrations), indicating that the implementation of policies has been successful in terms of the number of people affected. The opposite effect of population-weighting is observed in areas within Western Asia and Northern Africa where an increasing trend in population-weighted concentrations (from 42.0 to 43.1. μg/m 3 ) contains lower values than for concentrations (from 50.7 to 52.6 μg/m 3 ). In this region, concentrations are inversely correlated with population, reflecting the high concentrations associated with desert dust in areas of lower population density.

Long-term policies to reduce air pollution have been shown to be effective and have been implemented in many countries, notably in Europe and the United States. However, even in countries with the cleanest air there are large numbers of people exposed to harmful levels of air pollution. Although precise quantification of the outcomes of specific policies is difficult, coupling the evidence for effective interventions with global, regional and local trends in air pollution can provide essential information for the evidence base that is key in informing and monitoring future policies. There have been major advances in methods that expand the knowledge base about impacts of air pollution on health, from evidence on the health effects 26 , modelling levels of air pollution 1 , 11 and quantification of health impacts that can be used to monitor and report on progress towards the air pollution-related indicators of the Sustainable Development Goals: SDG 3.9.1 (mortality rate attributed to household and ambient air pollution); SDG 7.1.2 (proportion of population with primary reliance on clean fuels and technology); and SDG 11.6.2 (annual mean levels of fine particulate matter (e.g., PM 2.5 and PM 10 ) in cities (population weighted)) 1 . There is a continuing need for further research, collaboration and sharing of good practice between scientists and international organisations, for example the WHO and the World Meteorological Organization, to improve modelling of global air pollution and the assessment of its impact on health. This will include developing models that address specific questions, including for example the effects of transboundary air pollution and desert dust, and to produce tools that provide policy makers with the ability to assess the effects of interventions and to accurately predict the potential effects of proposed policies.

Globally, the population exposed to PM 2.5 levels above the current WHO AQG (annual average of 10 μg/m 3 ) has fallen from 94.2% in 2010 to 90.0% in 2016, driven largely by decreases in North America and Europe (from 71.0% in 2010 to 48.6% in 2016). However, no such improvements are seen in other regions where the proportion has remained virtually constant and extremely high (e.g., greater than 99% in Central, Southern, Eastern and South-Eastern Asia Sustainable Development Goal (SDG) regions. See Supplementary Information for more details).

The problem, and the need for solutions, is not confined to cities: across much of the world the vast majority of people living in rural areas are also exposed to levels above the guidelines. Although there are differences when considering urban and rural areas in North America and Europe, in the vast majority of the world populations living in both urban and rural areas are exposed to levels that are above the AQGs. However, in other regions the story is very different (see Supplementary Information Fig. 7.1 and Supplementary Information Sections 7 and 8), for example population-weighted concentrations in rural areas in the Central and Southern Asia (55.5 μg/m 3 ), Sub-Saharan Africa (39.1 μg/m 3 ), Western Asia and Northern Africa (42.7 μg/m 3 ) and Eastern Asia and South-Eastern Asia (34.3 μg/m 3 ) regions (in 2016) were all considerably above the AQG. From 2010 to 2016 population-weighted concentrations in rural areas in the Central and Southern Asia region rose by approximately 11% (from 49.8 to 55.5 μg/m 3 ; see Supplementary Information Fig. 7.1 and Supplementary Information Sections 7 and 8). This is largely driven by large rural populations in India where 67.2% of the population live in rural areas 27 . Addressing air pollution in both rural and urban settings should therefore be a key priority in effectively reducing the burden of disease associated with air pollution.

Attempts to mitigate the effects of air pollution have varied according to its source and local conditions, but in all cases cooperation across sectors and at different levels, urban, regional, national and international, is crucial 28 . Policies and investments supporting affordable and sustainable access to clean energy, cleaner transport and power generation, as well as energy-efficient housing and municipal waste management can reduce key sources of outdoor air pollution. Interventions would not only improve health but also reduce climate pollutants and serve as a catalyst for local economic development and the promotion of healthy lifestyles.

Assessment of trends in global air pollution requires comprehensive information on concentrations over time for every country. This information is primarily based on ground monitoring (GM) from 9690 monitoring locations around the world from the WHO cities database for 2010–2016. However, there are regions in this may be limited if not completely unavailable, particularly for earlier years (see Supplementary Information). Even in countries where GM networks are well established, there will still be gaps in spatial coverage and missing data over time. The Data Integration Model for Air Quality (DIMAQ) supplements GM with information from other sources including estimates of PM2.5 from satellite retrievals and chemical transport models, population estimates and topography (e.g., elevation). Specifically, satellite-based estimates that combine aerosol optical depth retrievals with information from the GEOS-Chem chemical transport model 29 were used, together with estimates of sulfate, nitrate, ammonium, organic carbon and mineral dust 30 .

The most recent release of the WHO ambient air quality database, for the first time, contains data from GM for multiple years, where available The version of DIMAQ used here builds on the original version 11 , 30 by allowing data from multiple years to be modelled simultaneously, with the relationship between GMs and satellite-based estimates allowed to vary (smoothly) over time. The result is a comprehensive set of high-resolution (10 km × 10 km) estimates of PM2.5 for each year (2010–2016) for every country.

In order to produce population-weighted concentrations, a comprehensive set of population data on a high-resolution grid (Gridded Population of the World (GPW v4) database 31 ) was combined with estimates from DIMAQ. In addition, the Global Human Settlement Layer 32 was used to define areas as either urban, sub-urban or rural (based on land-use, derived from satellite images, and population estimates). A further dichotomous classification of whether grid-cells within a particular country were urban or rural (allocating sub-urban as either urban or rural) was based on providing the best alignment (at the country-level) to the estimates of urban-rural populations produced by the United Nations 27 .

It is noted that the estimates from DIMAQ used in this article may differ slightly from those used in the WHO estimates of the global burden of disease associated with ambient air pollution 1 , and the associated estimates of air pollution related SDG indicators, due to recent updates in the database and further quality assurance procedures.

Data availability

The estimates of PM 2.5 data that support the findings of this work are available from https://www.who.int/airpollution/data/en/ .

Ambient air pollution: Global assessment of exposure and BOD, update 2018. WHO (2020) (In press).

Krzyzanowski, M. & Cohen, A. Update of WHO air quality guidelines. Air Qual. Atmosphere Health 1 , 7–13 (2008).

Article   Google Scholar  

Zheng, Y. et al. Air quality improvements and health benefits from China’s clean air action since 2013. Environ. Res. Lett. 12 , 114020 (2017).

Turnock, S. T. et al. The impact of European legislative and technology measures to reduce air pollutants on air quality, human health and climate. Environ. Res. Lett. 11 , 024010 (2016).

Zhang, Y. et al. Long-term trends in the ambient PM 2.5 - and O 3 -related mortality burdens in the United States under emission reductions from 1990 to 2010. Atmos. Chem. Phys. 18 , 15003–15016 (2018).

Kuklinska, K., Wolska, L. & Namiesnik, J. Air quality policy in the U.S. and the EU – a review. Atmos. Pollut. Res 6 , 129–137 (2015).

Guerreiro, C. B. B., Foltescu, V. & de Leeuw, F. Air quality status and trends in Europe. Atmos. Environ. 98 , 376–384 (2014).

Byrne, A. The 1979 convention on long-range transboundary air pollution: assessing its effectiveness as a multilateral environmental regime after 35 Years. Transnatl. Environ. Law 4 , 37–67 (2015).

Crippa, M. et al. Forty years of improvements in European air quality: regional policy-industry interactions with global impacts. Atmos. Chem. Phys. 16 , 3825–3841 (2016).

Butt, E. W. et al. Global and regional trends in particulate air pollution and attributable health burden over the past 50 years. Environ. Res. Lett. 12 , 104017 (2017).

Shaddick, G. et al. Data integration model for air quality: a hierarchical approach to the global estimation of exposures to ambient air pollution. J. R. Stat. Soc. Ser. C. Appl. Stat. 67 , 231–253 (2018).

World Bank Country and Lending Groups—World Bank data. https://datahelpdesk.worldbank.org/knowledgebase/articles/906519-world-bank-country-and-lending-groups (Accessed 3rd December 2018).

Guo, H. et al. Assessment of PM2.5 concentrations and exposure throughout China using ground observations. Sci. Total Environ. 601–602 , 1024–1030 (2017).

Ganor, E., Osetinsky, I., Stupp, A. & Alpert, P. Increasing trend of African dust, over 49 years, in the eastern Mediterranean. J. Geophys. Res. 115 , 1–7 (2010).

Google Scholar  

Goudie, A. S. & Middleton, N. J. Desert Dust in the Global System . (Springer Science & Business Media, 2006).

Mahowald, N. M. et al. Observed 20th century desert dust variability: impact on climate and biogeochemistry. Atmos. Chem. Phys. 10 , 10875–10893 (2010).

Stanelle, T., Bey, I., Raddatz, T., Reick, C. & Tegen, I. Anthropogenically induced changes in twentieth century mineral dust burden and the associated impact on radiative forcing. J. Geophys. Res. Atmosph 119 , 13526–13546 (2014).

Air quality in Europe (European Environment Agency, 2018). https://www.eea.europa.eu/publications/air-quality-in-europe-2018 .

Particulate Matter (PM2.5) Trends | National Air Quality: Status and Trends of Key Air Pollutants | US EPA. https://www.epa.gov/air-trends/particulate-matter-pm25-trends .

Chay, K., Dobkin, C. & Greenstone, M. The clean air act of 1970 and adult mortality. J. Risk Uncertain. 27 , 279–300 (2003).

Huang, J., Pan, X., Guo, X. & Li, G. Health impact of China’s air pollution prevention and control action plan: an analysis of national air quality monitoring and mortality data. Lancet Planet. Health 2 , e313–e323 (2018).

Heal, M. R., Kumar, P. & Harrison, R. M. Particles, air quality, policy and health. Chem. Soc. Rev. 41 , 6606–6630 (2012).

Chen, J. et al. A review of biomass burning: emissions and impacts on air quality, health and climate in China. Sci. Total Environ. 579 , 1000–1034 (2017).

Zhao, B. et al. Change in household fuels dominates the decrease in PM2.5 exposure and premature mortality in China in 2005–2015. Proc. Natl. Acad. Sci . 201812955 (2018). https://doi.org/10.1073/pnas.1812955115 .

Shen, H. et al. Urbanization-induced population migration has reduced ambient PM2.5 concentrations in China. Sci. Adv. 3 , e1700300 (2017).

Burnett, R. et al. Global estimates of mortality associated with long-term exposure to outdoor fine particulate matter. Proc. Natl Acad. Sci. 115 , 9592–9597 (2018).

World Urbanization Prospects - Population Division - United Nations. https://population.un.org/wup/Download/ (Accessed: 10th December 2018).

Towards Cleaner Air Scientific Assessment Report 2016- UNECE (2016). https://www.unece.org/index.php?id=42861 .

van Donkelaar, A. et al. Global estimates of fine particulate matter using a combined geophysical-statistical method with information from satellites, models, and monitors. Environ. Sci. Technol. 50 , 3762–3772 (2016).

Shaddick, G. et al. Data Integration for the assessment for population exposure to ambient air pollution for global burden of disease assessment. Environ. Sci. Technol. 52 , 9069–9078 (2018).

Center for International Earth Science Information Network (CIESIN) Columbia University. 2016. Gridded Population of the World, Version 4 (GPWv4): Population Count. NASA Socioeconomic Data and Applications Center (SEDAC), Palisades, NY. https://doi.org/10.7927/H4X63JVC . Accessed 3rd December 2018.

Pesaresi, M. et al. GHS Settlement grid following the REGIO model 2014 in application to GHSL Landsat and CIESIN GPW v4- multitemporal (1975-1990-2000-2015). European Commission, Joint Research Centre (JRC)[Dataset] http://data.europa.eu/89h/jrc-ghsl-ghs_smod_pop_globe_r2016a . Accessed: 3rd December 2018.

Download references

Acknowledgements

The authors would like to thank the WHO Data Integration Task Force, a multi-disciplinary group of experts established as part of the recommendations from the first meeting of the WHO Global Platform for Air Quality, Geneva, January 2014. The Task Force developed the Data Integration Model for Air Quality and consists of the first author, Michael Brauer, Aaron van Donkelaar, Rick Burnett, Howard H. Chang, Aaron Cohen, Rita Van Dingenen, Yang Liu, Randall Martin, Lance A. Waller, Jason West, James V. Zidek and Annette Pruss-Ustun. The authors would like to give particular thanks to Michael Brauer who provided specialist expertise, together with data on ground measurements, and Aaron van Donkelaar and the Atmospheric Composition Analysis Group at Dalhousie University for providing estimates from satellite remote sensing. The authors would also like to thank Dan Simpson for technical expertise on implementing extensions to DIMAQ. Matthew L Thomas is supported by a scholarship from the EPSRC Centre for Doctoral Training in Statistical Applied Mathematics at Bath (SAMBa), under the project EP/L015684/1. The views expressed in this article are those of the authors and they do not necessarily represent the views, decisions or policies to institutions with which they are affiliated.

Author information

Authors and affiliations.

Department of Mathematics, University of Exeter, Exeter, UK

G. Shaddick

Department of Infectious Disease Epidemiology, Imperial College, London, UK

M. L. Thomas

World Health Organization, Geneva, Switzerland

P. Mudu, G. Ruggeri & S. Gumy

You can also search for this author in PubMed   Google Scholar

Contributions

GS, PM, and SG conceived the project and led the writing of the manuscript. MLT and GR performed the data analysis. GS and MLT developed the statistical model used to produce the estimates. All authors contributed to the writing of the manuscript.

Corresponding author

Correspondence to G. Shaddick .

Ethics declarations

Competing interests.

The authors declare no competing interests.

Additional information

Publisher’s note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Supplementary information

Supplementary information, rights and permissions.

Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/ .

Reprints and permissions

About this article

Cite this article.

Shaddick, G., Thomas, M.L., Mudu, P. et al. Half the world’s population are exposed to increasing air pollution. npj Clim Atmos Sci 3 , 23 (2020). https://doi.org/10.1038/s41612-020-0124-2

Download citation

Received : 22 February 2019

Accepted : 01 May 2020

Published : 17 June 2020

DOI : https://doi.org/10.1038/s41612-020-0124-2

Share this article

Anyone you share the following link with will be able to read this content:

Sorry, a shareable link is not currently available for this article.

Provided by the Springer Nature SharedIt content-sharing initiative

This article is cited by

Combined short-term and long-term emission controls improve air quality sustainably in china.

Nature Communications (2024)

Higher air pollution in wealthy districts of most low- and middle-income countries

• A. Patrick Behrer
• Sam Heft-Neal

Nature Sustainability (2024)

Dynamics of PM2.5 and network activity during extreme pollution events

• Nail F. Bashan

npj Climate and Atmospheric Science (2024)

Assessing long-term effects of gaseous air pollution exposure on mortality in the United States using a variant of difference-in-differences analysis

• Ziqing Tang

Scientific Reports (2024)

Substantial differences in source contributions to carbon emissions and health damage necessitate balanced synergistic control plans in China

• Huizhong Shen

Quick links

• Explore articles by subject
• Guide to authors
• Editorial policies

Sign up for the Nature Briefing: Anthropocene newsletter — what matters in anthropocene research, free to your inbox weekly.

45,000+ students realised their study abroad dream with us. Take the first step today

Meet top uk universities from the comfort of your home, here’s your new year gift, one app for all your, study abroad needs, start your journey, track your progress, grow with the community and so much more.

Verification Code

An OTP has been sent to your registered mobile no. Please verify

Thanks for your comment !

Our team will review it before it's shown to our readers.

• School Education /

Essay on Air Pollution for Students: Check Samples of 100 Words to 250 Words

• Updated on  
• Jun 2, 2024

Essay on Air Pollution : Invisible but insidious, air pollution silently infiltrates our lives, impacting health, the environment, and future generations. Through this blog, let’s explore its roots, repercussions, and remedies, which are essential in our quest for cleaner, healthier skies. Essay writing here becomes more crucial, to raise awareness about air pollution’s dire consequences and drive action for cleaner air.

Table of Contents

• 1 10-Line Essay on Air Pollution
• 2 What are the Causes of Air Pollution?
• 3 What are the effects of Air Pollution?
• 4 Essay on Air Pollution: How to Tackle Air Pollution?
• 5 Essay on Air Pollution Sample (100 Words)
• 6 Essay on Air Pollution Sample (250 Words)

Quick Read: Essay on Child Labour

10-Line Essay on Air Pollution

Below mentioned is a 10-lined essay on air pollution:

• Air pollution is caused by harmful substances known as pollutants.
• The pollutant comes from various sources, like vehicle gasses, forest fires, and other human activities.
• The two biggest sources of air pollution are the burning of fossil fuels and deforestation.
• Air pollution is harmful to humans because it can cause skin and respiratory diseases.
• Air pollution is equally harmful to plants and animals.
• Air pollution can also damage non-living things, such as ancient monuments constructed from marble and limestone.
• Air pollution leads to ozone layer depletion, climate change and global warming.
• Air pollution can damage ecosystems in forests.
• We must take effective steps to reduce air pollution.
• We can reduce air pollution by planting more trees and burning less fossil fuels.

What are the Causes of Air Pollution?

Air pollution is caused by various factors, including:

• Industrial Emissions: Factories and manufacturing processes release pollutants like chemicals and particulate matter into the air.
• Vehicle Emissions: Combustion engines in cars, trucks, and aeroplanes emit exhaust gases, including carbon monoxide and nitrogen oxides.
• Burning Fossil Fuels: The use of coal, oil, and natural gas for energy generation and heating releases pollutants and greenhouse gases.
• Agricultural Activities: Pesticides and fertilizers release chemicals, while livestock emit methane.
• Deforestation: Cutting down trees reduces the planet’s capacity to absorb pollutants.
• Waste Disposal: Improper disposal of waste leads to the release of harmful substances into the air.
• Natural Sources: Volcanic eruptions, dust storms, and wildfires can also contribute to air pollution.

What are the effects of Air Pollution?

Air pollution poses severe health and environmental risks. Short-term exposure can lead to respiratory issues, eye irritation, and exacerbation of pre-existing conditions. Long-term exposure is linked to chronic diseases such as lung cancer, heart disease, and respiratory disorders. 

Additionally, air pollution harms ecosystems, causing acid rain, damaging vegetation, and polluting water bodies. It also contributes to climate change by increasing greenhouse gas concentrations. Addressing air pollution is crucial to safeguard the human health and protecting the planet’s ecosystems and climate.

Essay on Air Pollution: How to Tackle Air Pollution?

Addressing air pollution is paramount for a healthier planet. By curbing emissions, adopting clean technologies, and fostering sustainable practices, we can safeguard our environment and public health. Here are some key points on how to tackle air pollution:

• Reduce Vehicle Emissions
• Improve Industrial Practices
• Plant more trees
• Reduce Indoor Air Pollution
• Promote Renewable Energy
• Encourage Sustainable Practices
• Raise Public Awareness
• Reduce Open Burning
• International Cooperation

Tackling air pollution requires a multi-faceted approach involving government policies, community engagement, and individual responsibility.

Must Read: Essay On Global Warming

Essay on Air Pollution Sample (100 Words)

Air pollution is a pressing environmental issue with far-reaching consequences. It occurs when harmful substances, such as particulate matter and toxic gases, contaminate the atmosphere. These pollutants result from various sources, including industrial emissions, vehicular exhaust, and agricultural activities.

The consequences of air pollution are severe, impacting both human health and the environment. Prolonged exposure to polluted air can lead to respiratory diseases, cardiovascular issues, and even premature death. Additionally, air pollution harms ecosystems, leading to reduced crop yields and biodiversity loss.

Mitigating air pollution requires collective efforts, including stricter emission regulations, cleaner energy sources, and promoting public awareness. By addressing this issue, we can safeguard our health and preserve the environment for future generations.

Essay on Air Pollution Sample (250 Words)

Air pollution is a pressing global issue that affects the health and well-being of people and the environment. It occurs when harmful substances, such as particulate matter, nitrogen oxides, sulfur dioxide, and volatile organic compounds, are released into the atmosphere. This pollution can have dire consequences for both humans and the planet.

First and foremost, air pollution poses a significant threat to human health. Particulate matter and toxic gases can enter the respiratory system, leading to various respiratory diseases like asthma and bronchitis. Long-term exposure to polluted air has also been linked to cardiovascular diseases, lung cancer, and premature death. Vulnerable populations such as children, the elderly, and those with pre-existing health conditions are at higher risk.

Additionally, air pollution has adverse effects on the environment. It contributes to climate change by increasing the concentration of greenhouse gases in the atmosphere, leading to rising global temperatures and more frequent extreme weather events. Moreover, pollutants can harm ecosystems, contaminate water bodies, and damage crops, impacting food security.

The sources of air pollution are diverse, including industrial processes, transportation, agriculture, and energy production. To combat this problem, governments, industries, and individuals must take collective action. Implementing stricter emission standards for vehicles and industrial facilities, transitioning to cleaner energy sources, and promoting public transportation are essential steps in reducing air pollution.

In conclusion, air pollution is a critical issue that affects human health and the environment. Its detrimental effects on respiratory health and its contributions to climate change necessitate urgent action. By adopting sustainable practices and reducing emissions, we can mitigate the impact of air pollution and create a healthier and more sustainable future for all.

Ans. Air pollution is the contamination of air due to the presence of substances in the atmosphere that are harmful to the health of humans and other living beings, or cause damage to the climate or materials.

Ans. To prevent air pollution, reduce vehicle emissions by using public transport, carpooling, or opting for electric vehicles. Promote clean energy sources like wind and solar power. Implement strict industrial emissions standards. Encourage reforestation and green spaces. Educate the public about responsible waste disposal and advocate for clean energy policies.

Related Reads:-    

We hope this blog gave you an idea about how to write and present an essay on air pollution that puts forth your opinions. The skill of writing an essay comes in handy when appearing for standardized language tests. Thinking of taking one soon? Leverage Edu provides the best online test prep for the same via Leverage Live . Register today to know more!

Amisha Khushara

Hey there! I'm a content writer who turns complex ideas into clear, engaging stories. Think of me as your translator, taking expert knowledge and making it interesting and relatable for everyone.

Leave a Reply Cancel reply

Save my name, email, and website in this browser for the next time I comment.

Contact no. *

Connect With Us

45,000+ students realised their study abroad dream with us. take the first step today..

Resend OTP in

Need help with?

Study abroad.

UK, Canada, US & More

IELTS, GRE, GMAT & More

Scholarship, Loans & Forex

Country Preference

New Zealand

Which English test are you planning to take?

Which academic test are you planning to take.

Not Sure yet

When are you planning to take the exam?

Already booked my exam slot

Within 2 Months

Want to learn about the test

Which Degree do you wish to pursue?

When do you want to start studying abroad.

January 2025

September 2025

What is your budget to study abroad?

How would you describe this article ?

Please rate this article

We would like to hear more.

Have something on your mind?

Make your study abroad dream a reality in January 2022 with

India's Biggest Virtual University Fair

Essex Direct Admission Day

Why attend .

Don't Miss Out

Air Pollution: Everything You Need to Know

How smog, soot, greenhouse gases, and other top air pollutants are affecting the planet—and your health.

• Share this page block

What is air pollution?

What causes air pollution, effects of air pollution, air pollution in the united states, air pollution and environmental justice, controlling air pollution, how to help reduce air pollution, how to protect your health.

Air pollution  refers to the release of pollutants into the air—pollutants that are detrimental to human health and the planet as a whole. According to the  World Health Organization (WHO) , each year, indoor and outdoor air pollution is responsible for nearly seven million deaths around the globe. Ninety-nine percent of human beings currently breathe air that exceeds the WHO’s guideline limits for pollutants, with those living in low- and middle-income countries suffering the most. In the United States, the  Clean Air Act , established in 1970, authorizes the U.S. Environmental Protection Agency (EPA) to safeguard public health by regulating the emissions of these harmful air pollutants.

“Most air pollution comes from energy use and production,” says  John Walke , director of the Clean Air team at NRDC. Driving a car on gasoline, heating a home with oil, running a power plant on  fracked gas : In each case, a fossil fuel is burned and harmful chemicals and gases are released into the air.

“We’ve made progress over the last 50 years in improving air quality in the United States, thanks to the Clean Air Act. But climate change will make it harder in the future to meet pollution standards, which are designed to  protect health ,” says Walke.

Air pollution is now the world’s fourth-largest risk factor for early death. According to the 2020  State of Global Air  report —which summarizes the latest scientific understanding of air pollution around the world—4.5 million deaths were linked to outdoor air pollution exposures in 2019, and another 2.2 million deaths were caused by indoor air pollution. The world’s most populous countries, China and India, continue to bear the highest burdens of disease.

“Despite improvements in reducing global average mortality rates from air pollution, this report also serves as a sobering reminder that the climate crisis threatens to worsen air pollution problems significantly,” explains  Vijay Limaye , senior scientist in NRDC’s Science Office. Smog, for instance, is intensified by increased heat, forming when the weather is warmer and there’s more ultraviolet radiation. In addition, climate change increases the production of allergenic air pollutants, including mold (thanks to damp conditions caused by extreme weather and increased flooding) and pollen (due to a longer pollen season). “Climate change–fueled droughts and dry conditions are also setting the stage for dangerous wildfires,” adds Limaye. “ Wildfire smoke can linger for days and pollute the air with particulate matter hundreds of miles downwind.”

The effects of air pollution on the human body vary, depending on the type of pollutant, the length and level of exposure, and other factors, including a person’s individual health risks and the cumulative impacts of multiple pollutants or stressors.

Smog and soot

These are the two most prevalent types of air pollution. Smog (sometimes referred to as ground-level ozone) occurs when emissions from combusting fossil fuels react with sunlight. Soot—a type of  particulate matter —is made up of tiny particles of chemicals, soil, smoke, dust, or allergens that are carried in the air. The sources of smog and soot are similar. “Both come from cars and trucks, factories, power plants, incinerators, engines, generally anything that combusts fossil fuels such as coal, gasoline, or natural gas,” Walke says.

Smog can irritate the eyes and throat and also damage the lungs, especially those of children, senior citizens, and people who work or exercise outdoors. It’s even worse for people who have asthma or allergies; these extra pollutants can intensify their symptoms and trigger asthma attacks. The tiniest airborne particles in soot are especially dangerous because they can penetrate the lungs and bloodstream and worsen bronchitis, lead to heart attacks, and even hasten death. In  2020, a report from Harvard’s T.H. Chan School of Public Health showed that COVID-19 mortality rates were higher in areas with more particulate matter pollution than in areas with even slightly less, showing a correlation between the virus’s deadliness and long-term exposure to air pollution. 

These findings also illuminate an important  environmental justice issue . Because highways and polluting facilities have historically been sited in or next to low-income neighborhoods and communities of color, the negative effects of this pollution have been  disproportionately experienced by the people who live in these communities.

Hazardous air pollutants

A number of air pollutants pose severe health risks and can sometimes be fatal, even in small amounts. Almost 200 of them are regulated by law; some of the most common are mercury,  lead , dioxins, and benzene. “These are also most often emitted during gas or coal combustion, incineration, or—in the case of benzene—found in gasoline,” Walke says. Benzene, classified as a carcinogen by the EPA, can cause eye, skin, and lung irritation in the short term and blood disorders in the long term. Dioxins, more typically found in food but also present in small amounts in the air, is another carcinogen that can affect the liver in the short term and harm the immune, nervous, and endocrine systems, as well as reproductive functions.  Mercury  attacks the central nervous system. In large amounts, lead can damage children’s brains and kidneys, and even minimal exposure can affect children’s IQ and ability to learn.

Another category of toxic compounds, polycyclic aromatic hydrocarbons (PAHs), are by-products of traffic exhaust and wildfire smoke. In large amounts, they have been linked to eye and lung irritation, blood and liver issues, and even cancer.  In one study , the children of mothers exposed to PAHs during pregnancy showed slower brain-processing speeds and more pronounced symptoms of ADHD.

Greenhouse gases

While these climate pollutants don’t have the direct or immediate impacts on the human body associated with other air pollutants, like smog or hazardous chemicals, they are still harmful to our health. By trapping the earth’s heat in the atmosphere, greenhouse gases lead to warmer temperatures, which in turn lead to the hallmarks of climate change: rising sea levels, more extreme weather, heat-related deaths, and the increased transmission of infectious diseases. In 2021, carbon dioxide accounted for roughly 79 percent of the country’s total greenhouse gas emissions, and methane made up more than 11 percent. “Carbon dioxide comes from combusting fossil fuels, and methane comes from natural and industrial sources, including large amounts that are released during oil and gas drilling,” Walke says. “We emit far larger amounts of carbon dioxide, but methane is significantly more potent, so it’s also very destructive.” 

Another class of greenhouse gases,  hydrofluorocarbons (HFCs) , are thousands of times more powerful than carbon dioxide in their ability to trap heat. In October 2016, more than 140 countries signed the Kigali Agreement to reduce the use of these chemicals—which are found in air conditioners and refrigerators—and develop greener alternatives over time. (The United States officially signed onto the  Kigali Agreement in 2022.)

Pollen and mold

Mold and allergens from trees, weeds, and grass are also carried in the air, are exacerbated by climate change, and can be hazardous to health. Though they aren’t regulated, they can be considered a form of air pollution. “When homes, schools, or businesses get water damage, mold can grow and produce allergenic airborne pollutants,” says Kim Knowlton, professor of environmental health sciences at Columbia University and a former NRDC scientist. “ Mold exposure can precipitate asthma attacks  or an allergic response, and some molds can even produce toxins that would be dangerous for anyone to inhale.”

Pollen allergies are worsening  because of climate change . “Lab and field studies are showing that pollen-producing plants—especially ragweed—grow larger and produce more pollen when you increase the amount of carbon dioxide that they grow in,” Knowlton says. “Climate change also extends the pollen production season, and some studies are beginning to suggest that ragweed pollen itself might be becoming a more potent allergen.” If so, more people will suffer runny noses, fevers, itchy eyes, and other symptoms. “And for people with allergies and asthma, pollen peaks can precipitate asthma attacks, which are far more serious and can be life-threatening.”

More than one in three U.S. residents—120 million people—live in counties with unhealthy levels of air pollution, according to the  2023  State of the Air  report by the American Lung Association (ALA). Since the annual report was first published, in 2000, its findings have shown how the Clean Air Act has been able to reduce harmful emissions from transportation, power plants, and manufacturing.

Recent findings, however, reflect how climate change–fueled wildfires and extreme heat are adding to the challenges of protecting public health. The latest report—which focuses on ozone, year-round particle pollution, and short-term particle pollution—also finds that people of color are 61 percent more likely than white people to live in a county with a failing grade in at least one of those categories, and three times more likely to live in a county that fails in all three.

In rankings for each of the three pollution categories covered by the ALA report, California cities occupy the top three slots (i.e., were highest in pollution), despite progress that the Golden State has made in reducing air pollution emissions in the past half century. At the other end of the spectrum, these cities consistently rank among the country’s best for air quality: Burlington, Vermont; Honolulu; and Wilmington, North Carolina. 

No one wants to live next door to an incinerator, oil refinery, port, toxic waste dump, or other polluting site. Yet millions of people around the world do, and this puts them at a much higher risk for respiratory disease, cardiovascular disease, neurological damage, cancer, and death. In the United States, people of color are 1.5 times more likely than whites to live in areas with poor air quality, according to the ALA.

Historically, racist zoning policies and discriminatory lending practices known as  redlining  have combined to keep polluting industries and car-choked highways away from white neighborhoods and have turned communities of color—especially low-income and working-class communities of color—into sacrifice zones, where residents are forced to breathe dirty air and suffer the many health problems associated with it. In addition to the increased health risks that come from living in such places, the polluted air can economically harm residents in the form of missed workdays and higher medical costs.

Environmental racism isn't limited to cities and industrial areas. Outdoor laborers, including the estimated three million migrant and seasonal farmworkers in the United States, are among the most vulnerable to air pollution—and they’re also among the least equipped, politically, to pressure employers and lawmakers to affirm their right to breathe clean air.

Recently,  cumulative impact mapping , which uses data on environmental conditions and demographics, has been able to show how some communities are overburdened with layers of issues, like high levels of poverty, unemployment, and pollution. Tools like the  Environmental Justice Screening Method  and the EPA’s  EJScreen  provide evidence of what many environmental justice communities have been explaining for decades: that we need land use and public health reforms to ensure that vulnerable areas are not overburdened and that the people who need resources the most are receiving them.

In the United States, the  Clean Air Act  has been a crucial tool for reducing air pollution since its passage in 1970, although fossil fuel interests aided by industry-friendly lawmakers have frequently attempted to  weaken its many protections. Ensuring that this bedrock environmental law remains intact and properly enforced will always be key to maintaining and improving our air quality.

But the best, most effective way to control air pollution is to speed up our transition to cleaner fuels and industrial processes. By switching over to renewable energy sources (such as wind and solar power), maximizing fuel efficiency in our vehicles, and replacing more and more of our gasoline-powered cars and trucks with electric versions, we'll be limiting air pollution at its source while also curbing the global warming that heightens so many of its worst health impacts.

And what about the economic costs of controlling air pollution? According to a report on the Clean Air Act commissioned by NRDC, the annual  benefits of cleaner air  are up to 32 times greater than the cost of clean air regulations. Those benefits include up to 370,000 avoided premature deaths, 189,000 fewer hospital admissions for cardiac and respiratory illnesses, and net economic benefits of up to $3.8 trillion for the U.S. economy every year.

“The less gasoline we burn, the better we’re doing to reduce air pollution and the harmful effects of climate change,” Walke explains. “Make good choices about transportation. When you can, ride a bike, walk, or take public transportation. For driving, choose a car that gets better miles per gallon of gas or  buy an electric car .” You can also investigate your power provider options—you may be able to request that your electricity be supplied by wind or solar. Buying your food locally cuts down on the fossil fuels burned in trucking or flying food in from across the world. And most important: “Support leaders who push for clean air and water and responsible steps on climate change,” Walke says.

• “When you see in the news or hear on the weather report that pollution levels are high, it may be useful to limit the time when children go outside or you go for a jog,” Walke says. Generally, ozone levels tend to be lower in the morning.
• If you exercise outside, stay as far as you can from heavily trafficked roads. Then shower and wash your clothes to remove fine particles.
• The air may look clear, but that doesn’t mean it’s pollution free. Utilize tools like the EPA’s air pollution monitor,  AirNow , to get the latest conditions. If the air quality is bad, stay inside with the windows closed.
• If you live or work in an area that’s prone to wildfires,  stay away from the harmful smoke  as much as you’re able. Consider keeping a small stock of masks to wear when conditions are poor. The most ideal masks for smoke particles will be labelled “NIOSH” (which stands for National Institute for Occupational Safety and Health) and have either “N95” or “P100” printed on it.
• If you’re using an air conditioner while outdoor pollution conditions are bad, use the recirculating setting to limit the amount of polluted air that gets inside. 

This story was originally published on November 1, 2016, and has been updated with new information and links.

This NRDC.org story is available for online republication by news media outlets or nonprofits under these conditions: The writer(s) must be credited with a byline; you must note prominently that the story was originally published by NRDC.org and link to the original; the story cannot be edited (beyond simple things such as grammar); you can’t resell the story in any form or grant republishing rights to other outlets; you can’t republish our material wholesale or automatically—you need to select stories individually; you can’t republish the photos or graphics on our site without specific permission; you should drop us a note to let us know when you’ve used one of our stories.

Related Stories

When Customers and Investors Demand Corporate Sustainability

The Particulars of PM 2.5

What Are the Effects of Climate Change?

When you sign up, you’ll become a member of NRDC’s Activist Network. We will keep you informed with the latest alerts and progress reports.

• History & Society
• Science & Tech
• Biographies
• Animals & Nature
• Geography & Travel
• Arts & Culture
• Games & Quizzes
• On This Day
• One Good Fact
• New Articles
• Lifestyles & Social Issues
• Philosophy & Religion
• Politics, Law & Government
• World History
• Health & Medicine
• Browse Biographies
• Birds, Reptiles & Other Vertebrates
• Bugs, Mollusks & Other Invertebrates
• Environment
• Fossils & Geologic Time
• Entertainment & Pop Culture
• Sports & Recreation
• Visual Arts
• Demystified
• Image Galleries
• Infographics
• Top Questions
• Britannica Kids
• Saving Earth
• Space Next 50
• Student Center
• Introduction
• Fine particulates
• Carbon monoxide
• Sulfur dioxide
• Nitrogen dioxide
• Greenhouse gases
• Air pollution and air movement
• The global reach of air pollution
• Indoor air pollution

air pollution

Our editors will review what you’ve submitted and determine whether to revise the article.

• United States Environment Protection Agency - Air Pollution: Current and Future Challenges
• Natural Resources Defense Council - Air Pollution: Everything You Need to Know
• National Institute of Environmental Health Sciences - Air Pollution
• National Center for Biotechnology Information - PubMed Central - Air pollution: Impact and prevention
• Frontiers - Air pollution and rhinitis
• Environmental Pollution Centers - What is Air Pollution?
• air pollution - Student Encyclopedia (Ages 11 and up)
• Table Of Contents

Recent News

air pollution , release into the atmosphere of various gases , finely divided solids, or finely dispersed liquid aerosols at rates that exceed the natural capacity of the environment to dissipate and dilute or absorb them. These substances may reach concentrations in the air that cause undesirable health, economic, or aesthetic effects.

Major air pollutants

Criteria pollutants.

Clean, dry air consists primarily of nitrogen and oxygen —78 percent and 21 percent respectively, by volume. The remaining 1 percent is a mixture of other gases, mostly argon (0.9 percent), along with trace (very small) amounts of carbon dioxide , methane , hydrogen , helium , and more. Water vapour is also a normal, though quite variable, component of the atmosphere, normally ranging from 0.01 to 4 percent by volume; under very humid conditions the moisture content of air may be as high as 5 percent.

There are six major air pollutants that have been designated by the U.S. Environmental Protection Agency (EPA) as “criteria” pollutants — criteria meaning that the concentrations of these pollutants in the atmosphere are useful as indicators of overall air quality. The sources, acceptable concentrations, and effects of the criteria pollutants are summarized in the table.

The gaseous criteria air pollutants of primary concern in urban settings include sulfur dioxide , nitrogen dioxide , and carbon monoxide ; these are emitted directly into the air from fossil fuels such as fuel oil , gasoline , and natural gas that are burned in power plants, automobiles, and other combustion sources. Ozone (a key component of smog ) is also a gaseous pollutant; it forms in the atmosphere via complex chemical reactions occurring between nitrogen dioxide and various volatile organic compounds (e.g., gasoline vapours).

Airborne suspensions of extremely small solid or liquid particles called “particulates” (e.g., soot, dust, smokes, fumes, mists), especially those less than 10 micrometres (μm; millionths of a metre) in size, are significant air pollutants because of their very harmful effects on human health. They are emitted by various industrial processes, coal- or oil-burning power plants, residential heating systems, and automobiles. Lead fumes (airborne particulates less than 0.5 μm in size) are particularly toxic and are an important pollutant of many diesel fuels .

Except for lead, criteria pollutants are emitted in industrialized countries at very high rates, typically measured in millions of tons per year. All except ozone are discharged directly into the atmosphere from a wide variety of sources. They are regulated primarily by establishing ambient air quality standards, which are maximum acceptable concentrations of each criteria pollutant in the atmosphere, regardless of its origin. The six criteria pollutants are described in turn below.

Home — Essay Samples — Environment — Air Pollution — Air Pollution: Causes, Effects, and Proposed Solutions

Air Pollution: Causes, Effects, and Proposed Solutions

• Categories: Air Pollution Pollution

About this sample

Words: 645 |

Published: Feb 7, 2024

Words: 645 | Page: 1 | 4 min read

Table of contents

Causes of air pollution, effects of air pollution, current measures to control air pollution, shortcomings of current measures, proposed solutions.

Cite this Essay

To export a reference to this article please select a referencing style below:

Let us write you an essay from scratch

• 450+ experts on 30 subjects ready to help
• Custom essay delivered in as few as 3 hours

Get high-quality help

Verified writer

• Expert in: Environment

+ 120 experts online

By clicking “Check Writers’ Offers”, you agree to our terms of service and privacy policy . We’ll occasionally send you promo and account related email

No need to pay just yet!

Related Essays

3 pages / 1274 words

8 pages / 3471 words

4 pages / 1794 words

3 pages / 1557 words

Remember! This is just a sample.

You can get your custom paper by one of our expert writers.

121 writers online

Still can’t find what you need?

Browse our vast selection of original essay samples, each expertly formatted and styled

Related Essays on Air Pollution

Pollution is the presence of harmful substances or contaminants in the environment that cause negative impacts on living organisms. Pollution has been a significant problem for many years, and its effects continue to worsen day [...]

Klinkenborg, Verlyn. 'Our Vanishing Night.' 50 Essays. Edited by Samuel Cohen, pp. 216-219. Print.Burdick, Alan. 'The Truth About Invasive Species.' 50 Essays. Edited by Samuel Cohen, pp. 79-85. Print.'Air Pollution.' National [...]

The air we breathe today is full of toxic and hazardous pollution. Pollution is a big problem to our health and the environment. Pollution is created by individuals, communities or industries that collect and dispose pollutants [...]

In the years 2023-2024, concerns over chemical exposure from cleaning products and the prevalence of smog have become increasingly significant. These issues pose substantial risks to both human health and the environment, [...]

Air pollution has continued to increase over recent decades, particularly in Vietnam. The World Health Organization’s cancer agency said, the air we breathe is laced with cancer-causing substances and is being officially [...]

Carbon is critical to sustain a huge range of Earth’s functions. It is abundant in the atmosphere (air), biosphere (living and dead organisms), hydrosphere (oceans, rivers, and lakes), and lithosphere (soli and rocks). These act [...]

Related Topics

By clicking “Send”, you agree to our Terms of service and Privacy statement . We will occasionally send you account related emails.

Where do you want us to send this sample?

By clicking “Continue”, you agree to our terms of service and privacy policy.

Be careful. This essay is not unique

This essay was donated by a student and is likely to have been used and submitted before

Download this Sample

Free samples may contain mistakes and not unique parts

Sorry, we could not paraphrase this essay. Our professional writers can rewrite it and get you a unique paper.

Please check your inbox.

We can write you a custom essay that will follow your exact instructions and meet the deadlines. Let's fix your grades together!

Get Your Personalized Essay in 3 Hours or Less!

We use cookies to personalyze your web-site experience. By continuing we’ll assume you board with our cookie policy .

• Instructions Followed To The Letter
• Deadlines Met At Every Stage
• Unique And Plagiarism Free

Essay on Air Pollution for Students and Children

500+ words essay on air pollution.

Essay on Air Pollution – Earlier the air we breathe in use to be pure and fresh. But, due to increasing industrialization and concentration of poisonous gases in the environment the air is getting more and more toxic day by day. Also, these gases are the cause of many respiratory and other diseases . Moreover, the rapidly increasing human activities like the burning of fossil fuels, deforestation is the major cause of air pollution.

How Air Gets Polluted?

The fossil fuel , firewood, and other things that we burn produce oxides of carbons which got released into the atmosphere. Earlier there happens to be a large number of trees which can easily filter the air we breathe in. But with the increase in demand for land, the people started cutting down of trees which caused deforestation. That ultimately reduced the filtering capacity of the tree.

Moreover, during the last few decades, the numbers of fossil fuel burning vehicle increased rapidly which increased the number of pollutants in the air .

Causes Of Air Pollution

Its causes include burning of fossil fuel and firewood, smoke released from factories , volcanic eruptions, forest fires, bombardment, asteroids, CFCs (Chlorofluorocarbons), carbon oxides and many more.

Besides, there are some other air pollutants like industrial waste, agricultural waste, power plants, thermal nuclear plants, etc.

Greenhouse Effect

The greenhouse effect is also the cause of air pollution because air pollution produces the gases that greenhouse involves. Besides, it increases the temperature of earth surface so much that the polar caps are melting and most of the UV rays are easily penetrating the surface of the earth.

Get the huge list of more than 500 Essay Topics and Ideas

Effects Of Air Pollution On Health

Moreover, it increases the rate of aging of lungs, decreases lungs function, damage cells in the respiratory system.

Ways To Reduce Air Pollution

Although the level of air pollution has reached a critical point. But, there are still ways by which we can reduce the number of air pollutants from the air.

Reforestation- The quality of air can be improved by planting more and more trees as they clean and filter the air.

Policy for industries- Strict policy for industries related to the filter of gases should be introduced in the countries. So, we can minimize the toxins released from factories.

Use of eco-friendly fuel-  We have to adopt the usage of Eco-friendly fuels such as LPG (Liquefied Petroleum Gas), CNG (Compressed Natural Gas), bio-gas, and other eco-friendly fuels. So, we can reduce the amount of harmful toxic gases.

To sum it up, we can say that the air we breathe is getting more and more polluted day by day. The biggest contribution to the increase in air pollution is of fossil fuels which produce nitric and sulphuric oxides. But, humans have taken this problem seriously and are devotedly working to eradicate the problem that they have created.

Above all, many initiatives like plant trees, use of eco-friendly fuel are promoted worldwide.

{ “@context”: “https://schema.org”, “@type”: “FAQPage”, “mainEntity”: [{ “@type”: “Question”, “name”: “Mention five effect of air pollution on human health?”, “acceptedAnswer”: { “@type”: “Answer”, “text”: “The major risk factor related to human health are asthma, lung cancer, Alzheimer, psychological complications, and autism. Besides, there are other effects of air pollution on a person’s health.”} }, { “@type”: “Question”, “name”: “What is the effect of air pollution in the environment?”, “acceptedAnswer”: { “@type”: “Answer”, “text”:”Acid, rain, ozone depletion, greenhouse gases, smog are many other things are the cause of air pollution that affect the environment severely.”} }] }

Customize your course in 30 seconds

Which class are you in.

• Travelling Essay
• Picnic Essay
• Our Country Essay
• My Parents Essay
• Essay on Favourite Personality
• Essay on Memorable Day of My Life
• Essay on Knowledge is Power
• Essay on Gurpurab
• Essay on My Favourite Season
• Essay on Types of Sports

Leave a Reply Cancel reply

Your email address will not be published. Required fields are marked *

Download the App

Fact sheets

• Facts in pictures
• Publications
• Questions and answers
• Tools and toolkits
• Endometriosis
• Excessive heat
• Mental disorders
• Polycystic ovary syndrome
• All countries
• Eastern Mediterranean
• South-East Asia
• Western Pacific
• Data by country
• Country presence 
• Country strengthening 
• Country cooperation strategies 
• News releases
• Feature stories
• Press conferences
• Commentaries
• Photo library
• Afghanistan
• Cholera 
• Coronavirus disease (COVID-19)
• Greater Horn of Africa
• Israel and occupied Palestinian territory
• Disease Outbreak News
• Situation reports
• Weekly Epidemiological Record
• Surveillance
• Health emergency appeal
• International Health Regulations
• Independent Oversight and Advisory Committee
• Classifications
• Data collections
• Global Health Observatory
• Global Health Estimates
• Mortality Database
• Sustainable Development Goals
• Health Inequality Monitor
• Global Progress
• World Health Statistics
• Partnerships
• Committees and advisory groups
• Collaborating centres
• Technical teams
• Organizational structure

Initiatives

• General Programme of Work
• WHO Academy
• Investment in WHO
• WHO Foundation
• External audit
• Financial statements
• Internal audit and investigations 
• Programme Budget
• Results reports
• Governing bodies
• World Health Assembly
• Executive Board
• Member States Portal
• Spotlight /

How air pollution is destroying our health

WHO data show that almost all of the global population (99%) breathe air that exceeds WHO  guideline limits  and contains high levels of  pollutants , with low- and middle-income countries (LMIC) suffering from the highest exposures.

Ambient (outdoor) air pollution in both cities and rural areas is causing fine particulate matter which results in strokes, heart diseases, lung cancer, and acute and chronic respiratory diseases.  

Additionally, around 2.6 billion people are exposed to dangerous levels of household air pollution from using polluting open fires or simple stoves for cooking fuelled by kerosene, biomass (wood, animal dung and crop waste) and coal.

First Global Conference on Air Pollution and Health

To rally the world towards major commitments to fight this problem, WHO and partners convened the first  Global Conference on Air Pollution and Health  in Geneva on 29 October – 1 November 2018. The conference raised awareness of this growing public health challenge and shared information and tools on the health risks of air pollution and its interventions.

This conference showcased some of WHO’s work on air pollution, including the findings of its Global Platform on Air Quality and Health. This platform, whose diverse membership includes researchers, civil society, UN agencies and other partner institutions, reviewed the data on air quality and health. For example, the platform worked on techniques to more accurately attribute air pollution coming from different sources of pollution. Ongoing work includes improving estimates of air quality by combining the data from various air quality monitoring networks, atmospheric modelling and satellite remote sensing.

Health impacts of air pollution

There are two main types of air pollution: ambient air pollution (outdoor pollution) and household air pollution (indoor air pollution). Ambient air pollution is a major environmental health problem affecting everyone in low-, middle-, and high-income countries as its source – combustion of fossil fuel – is ubiquitous. Household air pollution is mainly caused by the use of solid fuels (such as wood, crop wastes, charcoal, coal and dung) and kerosene in open fires and inefficient stoves. Most of these people are poor and live in low- and middle-income countries.

Exposure to smoke from cooking fires causes 3.2 million premature deaths each year, mostly in low- and middle-income countries, where polluting fuels and technologies are used every day, particularly at home for cooking, heating and lighting. Women and children, who tend to spend more time indoors, are affected the most. LMIC also suffer the greatest from exposure ambient air pollution with 3.68 million premature deaths each year, which is almost 8 times the mortality rates in high income countries (0.47 million).

The main pollutants are:

-  particulate matter, a mix of solid and liquid droplets, with larger particles (PM 10 ) arising from pollen, sea spray and wind-blown dust from erosion, agricultural spaces, roadways and mining operations, while finer particles (PM2.5) can be derived from primary sources (for example combustion of fuels in power generation facilities, industries or vehicles) and secondary sources (for example chemical reactions between gases)

-  nitrogen dioxide (NO 2 ), a gas from combustion of fuels in processes such as those used for furnaces, gas stoves, transportation, industry and power generation;

-  sulfur dioxide, another gas mainly from the combustion of fossil fuels for domestic heating, industries and power generation; and

-  ozone at ground level, caused by a chemical reaction of gases, such as NO 2 , in the presence of sunlight. The pollutant that is most commonly monitored by regulatory frameworks and for which a lot of evidence of adverse health impact is available is particulate matter followed by nitrogen dioxide.

Ambient (outdoor) air pollution

Household air pollution

How air pollution affects our body

Particles with a diameter of 10 microns or less (≤ PM 10 ) can penetrate and lodge deep inside the lungs, causing irritation, inflammation and damaging the lining of the respiratory tract. Smaller, more health-damaging particles with a diameter of 2.5 microns or less (≤ PM 2.5 – 60 of them make up the width of a human hair) can penetrate the lung barrier and enter the blood system, affecting all major organs of the body. These pollutants increase the risk of heart and respiratory diseases, as well as lung cancer and strokes.

Ozone is a major factor in causing asthma (or making it worse), and nitrogen dioxide and sulfur dioxide can also cause asthma, bronchial symptoms, lung inflammation and reduced lung function. In 2021 WHO updated the Global Air Quality Guidelines, which recommend the maximum safe level for PM 2.5 annual average concentration of 5 μg/m 3  or less. The guidelines provide evidence of the damage air pollution inflicts on human health, at even lower concentrations than previously understood. The updated guidelines provide recommendations on air quality guideline levels as well as interim targets for six key air pollutants. They also offer qualitative statements on good practices for the management of certain types of particulate matter (PM), for example, black carbon/elemental carbon, ultrafine particles, and particles originating from sand and dust storms, for which there is insufficient quantitative evidence to derive AQG levels.

Air pollution has a disastrous effect on children; there were more than 5 million deaths of children under the age of 5 years. More than 27% of those deaths – 1.7 million – were attributable to environmental factors, with air pollution foremost among them. Globally, lower respiratory infections are the second leading cause of death for children under 5 years. Every year, 442 000 children (as of 2022) younger than 5 years die prematurely from breathing polluted air. Evidence suggests that air pollution could also harm children before they are born (reduced birth weight) through their mothers' exposure. There is emerging evidence linking air pollution exposure to cancer, neurodevelopmental and metabolic diseases in children.

As well as affecting our health, pollutants in the air are also causing long-term environmental damage by driving climate change, itself a major threat to health and well-being. 

Already in 2018, the UN Intergovernmental Panel on Climate Change warned that coal-fired electricity must end by 2050 if we are to limit global warming rises to 1.5 °C. If not, we may see a major climate crisis in just 20 years.

Affordable strategies exist to reduce emissions from energy, transport, waste management, housing and industrial sectors. These interventions often carry other benefits like reduced traffic and noise, increased physical activity and better land use – all of which contribute to improving health and well-being. WHO also supports cities with the data, tools and capacity to select, implement and track clean and healthy policies at the city level. Better air quality will benefit all of us, everywhere.

Training Video: Health Economic Assessment Tool (HEAT) for walking and cycling

Clean air & energy for health webinar #6 - The research landscape of household air pollution, clean energy access, and health in Rwanda

Save the Date: Global Conference on Air Pollution and Health

Second global conference on air pollution and health

Sustainable development goal indicator 3.9.1: mortality attributed to air pollution

In 2019, air pollution – both ambient and household – was the largest environmental risk to health, carrying responsibility for about one...

Clean household energy solutions toolkit (‎CHEST)‎: Household Multiple Emission Sources (HOMES) model

The WHO Household Multiple Emission Sources (HOMES) model can help policymakers and program planners determine how household air pollution levels and...

Compendium of WHO and other UN guidance in health and environment, 2024 update

This is the 2024 update of the Compendium of WHO and other UN guidance on health and environment. The Compendium is a comprehensive collection of available...

Policy Brief: Clean Household Energy Solutions Toolkit (CHEST)

A systematic review of the evidence has demonstrated the key role of clean household energy in improving global health, reaffirming the importance...

WHO announces the 2024 updated Compendium of interventions on environmental health

Health consequences of air pollution on populations

WHO to host second global conference on air pollution and health

Progress on basic energy access reverses for first time in a decade

3 ways SERVIR is supporting innovative air quality monitoring

Air quality affects all of us. According to the  World Health Organization , 99% of the global population breathes unhealthy, polluted air, contributing to over  7 million premature deaths from associated diseases. Reliable, timely data is essential to understand the root causes of air pollution and to issue alerts that keep communities safe. Unfortunately, 39% of all countries and territories  do not have access to regularly updated air quality information. SERVIR and its partners are working to close that gap, developing air quality services that decision makers can use to take action.

Here are three ways that SERVIR is working to create innovative air quality monitoring tools for cleaner air: 

Monitoring air quality in the Himalayas

SERVIR’s partner, the  International Centre for Integrated Mountain Development (ICIMOD) has been working since 2013 to tackle air pollution challenges in the  Hindu-Kush Himalaya (HKH) region.

Pollution from vehicles, factories, agricultural burning, and forest fires accumulate in the air due to a lack of seasonal rainfall, low winter temperatures, and calm winds. In the Kathmandu Valley in Nepal, pollutants can also get trapped by the surrounding mountains, resulting in severe smog. To address this, ICIMOD combines data from air quality monitoring stations and NASA Earth observations to provide reliable air quality monitoring information to policy makers and the public.

The   ICIMOD Air Quality Watch-HKH dashboard is a powerful and user-friendly interactive data platform that collects and visualizes specific air pollutants such as surface ozone (O3), carbon monoxide (CO), and particulate matter (PM2.5). The tool maps pollution hotspots and provides daily 48-hour air quality forecasts, helping users to both avoid locations most affected by pollution and to better manage extreme pollution events. A version of the Air Quality Watch is also shared on Nepal’s Department of Environment  website .

SERVIR Applied Scientist Aaron Naegar is also supporting ICIMOD to apply various algorithms, including machine learning techniques, to improve the platform’s ability to monitor emissions, pollutant transport, and local-level air quality. 

SERVIR HKH is building stakeholders capacity to put air quality data into action  and establishing cross-border networks to address transboundary haze and air pollution.

Upgrading air quality monitoring in Southeast Asia

SERVIR Southeast Asia , implemented by the Asian Disaster Preparedness Center , launched  the  AQ Tracker (formerly known as the Air Quality Explorer tool) in 2020 to monitor agricultural burning in northern Thailand. Since then, the tool has been expanded to provide current and forecasted air quality conditions across all of Southeast Asia. Users can now access more localized (5 km resolution) 3-day forecasts for PM2.5 pollution, fire hotspots for the last 24- and 48- hours, and near real-time NO2 concentrations from satellite observations. The tool uses plain-language to communicate air quality risks and precautionary measures users should take based on the conditions in their area. In 2023, Thailand’s national oil and gas company even consulted the tool to issue work-from-home orders to its 25,000+ employees during days with high air pollution. 

SERVIR Southeast Asia is also a key contributor of a  trilateral partnership between the United States, Thailand, and Laos on air quality. SERVIR Southeast Asia provides technical assistance to the Laos Ministry of Natural Resources and Environment to enhance their capacity to monitor and manage air quality through the use of publicly-available satellite data, ground observations, and informed policy applications. The training contributes toward the ultimate goal of upgrading regional air quality monitoring so countries can better collaborate to address air pollution and wildfires as transboundary issues.

Coordinating global air quality monitoring efforts 

Though air quality services across Asia have been successful, there is still a lot of work to be done.

“Air quality is a challenging area of work for applied science–for each region, we have different sets of data sources (satellites, ground monitoring, air borne sensors, models etc.), some freely available and some restricted,” said Dr. Alqamah Sayeed, the Air Quality and Health Thematic Lead for SERVIR’s Science Coordination Office. 

“My hope is that the Earth observation community can help make air quality data more accessible to more users by working towards a ‘one-stop shop’ that integrates multiple data sources into one place,” Sayeed shared.

Sayeed also noted the importance of understanding how air quality relates to other issues to support informed decision making. For example, SERVIR economist Dr. Reetwika Basu is analyzing the economic value of improved air quality monitoring. SERVIR Applied Scientist Dr. Gregory Charmichael is also continuing to support the Southeast Asia AQ Tracker by investigating the  effects of air pollution on public health .

Beyond Asia, SERVIR is supporting more accessible and reliable air quality data in other areas of the world that are disproportionately impacted by pollution. In Rwanda and Kenya, for instance, SERVIR Applied Scientist Dr. Rajesh Kumar is collaborating with national meteorological agencies to develop regional capacity and tools for near-real time air quality tracking and 2-day forecasting. 

By making data easier to use, drawing clear connections between air quality and other issues, and replicating these efforts in more regions, SERVIR ultimately hopes to improve health outcomes and community livelihoods by making the field of air quality monitoring more accessible.

Featured Services

Air quality monitoring for sustainable landscapes and better human health.

Air Quality Monitoring for Sustainable Landscapes and Better Human Health aims to reduce greenhouse gas emissions, improve climate resilience and promote better human health by using air quality data for informing and regulating the management of agricultural burning.

Monitoring and Prediction of Air Quality and Visibility Reductions in HKH

This service improves air quality monitoring through a web-based dashboard that was developed that utilizes publicly available observation data, satellite-based remote sensing products, and atmospheric models.

Related tags

Brewminate: A Bold Blend of News and Ideas

• Environment

Global Air Pollution Kills 2,000 Kids under the Age of Five Every Day

Share this:.

• Click to share on Twitter (Opens in new window)
• Click to share on Facebook (Opens in new window)
• Click to share on Reddit (Opens in new window)
• Click to share on Pinterest (Opens in new window)
• Click to share on Tumblr (Opens in new window)
• Click to share on LinkedIn (Opens in new window)
• Click to email a link to a friend (Opens in new window)

Air pollution now kills more children worldwide than poor sanitation and a lack of clean drinking water.

By Julia Conley Staff Writer Common Dreams

Air pollution is now the second-biggest killer of children under the age of five globally, a new report released Wednesday shows, with the climate emergency and the continued use of dirty energy sources inextricably linked to the growing risk faced by young children exposed to toxic fumes.

Each day, according to the  State of Global Air  report  by the Health Effects Institute (HEI) and the United Nations Children’s Fund (UNICEF), nearly 2,000 children under the age of five die from the effects of air pollution, with children in the Global South most at risk.

In most African countries, children under five are 100 times more likely to die from asthma and other other effects of air pollution than their counterparts in high-income countries.

In 2021, according to the report, air pollution was second only to malnutrition as a risk factor for death among young children. For the general population, air pollution overtook tobacco use as the second-leading cause of death worldwide, with high blood pressure still the leading cause.

The report should serve as “a stark reminder of the significant impacts air pollution has on human health, with far too much of the burden borne by young children, older populations, and low- and middle-income countries,”  said  Dr. Pallavi Pant, head of global health for HEI. “This points sharply at an opportunity for cities and countries to consider air quality and air pollution as high risk factors when developing health policies and other noncommunicable disease prevention and control programs.”

The analysis pointed to specific ways in which the effects of the climate emergency, such as prolonged droughts and the wildfires that have resulted from dry conditions in places like  Chile  and  Canad a , has made it more likely that children around the world will suffer from life-threatening air pollution.

“As droughts become more severe and prolonged and land becomes drier, wildfires ravage once-thriving forests and dust storms impact vast plains, filling the air with particles that linger for long periods of time,” reads the report.

The particles that HEI and UNICEF expressed the greatest concern about are  particulate matter (PM) 2.5 , which are smaller than 2.4 micrometers in diameter and can enter people’s bloodstreams and organs. PM 2.5 has been associated with heart disease, stroke, lung disease, and other health problems, and is behind 90% of air pollution-related deaths.

PM 2.5 is carried into communities through wildfire smoke and emissions, but can also be present in homes as people across the Global South—including 95% of the population in at least 18 African countries—rely on the burning of solid fuels for cooking.

About half a million children died in 2021 from exposure to polluted indoor air, according to HEI, as families rely on burning coal, paraffin, and other solid fuels.

Providing families with cleaner-burning cookstoves, grid electricity, and cleaner fuels has helped cut childhood deaths from pollution by 53% since 2000, according to the report, but the number of children continuing to die from indoor air pollution is “staggering,” said HEI.

“Our inaction is having profound effects on the next generation, with lifelong health and well-being impacts,”  said  Kitty van der Heijden, deputy executive director of UNICEF. “The global urgency is undeniable. It is imperative that governments and businesses consider these estimates and locally available data and use it to inform meaningful, child-focused action to reduce air pollution and protect children’s health.”

Along with wildfires and the use of dirty fuels for household needs, the climate emergency’s impact on global temperatures is linked to the high death toll from air pollution among children.

High temperatures can cause a higher prevalence of pollutants like nitrogen oxides and ozone, which can irritate people’s airways and cause more frequent and severe symptoms in people with asthma. Long-term exposure to ground-level ozone pollution is also linked to the development of chronic obstructive pulmonary disease (COPB), which accounted for nearly half a million of 8 million worldwide deaths related to air pollution in 2021.

While air pollution is disproportionately harming children and adults in low-income countries, wealthy countries including the U.S. are also affected by ozone pollution, which can be heightened by high temperatures.

“In 2021, nearly 50% of all ozone-related COPD deaths were in India (237,000 deaths) followed by China (125,600 deaths) and Bangladesh (15,000 deaths),” reads the report. “Notably, the United States—partly due to its sizable population, widespread ozone pollution, and relatively high rates of COPD—saw 14,000 deaths in 2021, more than any other high-income country.”

Asthma and Lung U.K. said HEI’s report showed the need for policymakers to pass laws providing funding for families to purchase electric vehicles or use other cleaner travel options.

“Air pollution’s impact on child health is unacceptable,”  said  the London-based group. “We need political parties to step up and commit to clean air laws now to reduce air pollution and protect children.”

Published by Common Dreams , 06.19.2024, under the terms of a Attribution-NonCommercial-NoDerivs 3.0 Unported license.

• Open access
• Published: 27 September 2024

Prenatal exposure to air pollution and maternal and fetal thyroid function: a systematic review of the epidemiological evidence

• Catherine O’Donnell 1 ,
• Erin J. Campbell 1 ,
• Sabrina McCormick 2 &
• Susan C. Anenberg 1  

Environmental Health volume  23 , Article number:  78 ( 2024 ) Cite this article

Metrics details

Exposure to ambient air pollution is a top risk factor contributing to the global burden of disease. Pregnant persons and their developing fetuses are particularly susceptible to adverse health outcomes associated with air pollution exposures. During pregnancy, the thyroid plays a critical role in fetal development, producing thyroid hormones that are associated with brain development. Our objective is to systematically review recent literature that investigates how prenatal exposure to air pollution affects maternal and fetal thyroid function.

Following the Navigation Guide Framework, we systematically reviewed peer-reviewed journal articles that examined prenatal exposures to air pollution and outcomes related to maternal and fetal thyroid function, evaluated the risk of bias for individual studies, and synthesized the overall quality and strength of the evidence.

We found 19 studies that collected data on pregnancy exposure windows spanning preconception to full term from 1999 to 2020 across nine countries. Exposure to fine particulate matter (PM 2.5 ) was most frequently and significantly positively associated with fetal/neonatal thyroid hormone concentrations, and inversely associated with maternal thyroid hormone concentrations. To a lesser extent, traffic-related air pollutants, such as nitrogen dioxide (NO 2 ) had significant effects on fetal/neonatal thyroid function but no significant effects on maternal thyroid function. However, the body of literature is challenged by risk of bias in exposure assessment methods and in the evaluation of confounding variables, and there is an inconsistency amongst effect estimates. Thus, using the definitions provided by the objective Navigation Guide Framework, we have concluded that there is limited, low quality evidence pertaining to the effects of prenatal air pollution exposure on maternal and fetal thyroid function.

To improve the quality of the body of evidence, future research should seek to enhance exposure assessment methods by integrating personal monitoring and high-quality exposure data (e.g., using spatiotemporally resolved satellite observations and statistical modeling) and outcome assessment methods by measuring a range of thyroid hormones throughout the course of pregnancy.

Peer Review reports

Introduction

Exposure to ambient air pollution is one of the top risk factors contributing to the global burden of disease and accounts for millions of deaths worldwide each year [ 1 ]. Long-term exposure to pollutants, such as particulate matter (PM), nitrogen dioxide (NO 2 ), and ground-level ozone (O 3 ), have an increasing impact on the public health burden associated with chronic disease outcomes, including ischemic heart disease, type 2 diabetes mellitus, chronic obstructive pulmonary disease (COPD), lung cancer, and others. While air pollution affects people of all ages and socioeconomic statuses, some vulnerable groups including pregnant persons, children, older adults, and those with preexisting health conditions experience an elevated risk of exposure to air pollution and thus, shoulder a greater burden of air pollution-related health consequences [ 2 ]. With an estimated 213 million pregnancies occurring annually and 99% of the world’s population breathing air that exceeds the World Health Organization’s (WHO) air quality limits [ 3 ], continuous exposure to air pollutants poses a serious health risk to pregnant persons and their children [ 4 , 5 ].

The complex, multifaceted interactions through which air pollution affects human health, influences not only maternal health, but fetal, perinatal, and postnatal health of the parent/child pair. Maternal exposure to air pollution has been associated with complications during pregnancy including gestational hypertension, gestational diabetes mellitus, and preeclampsia [ 6 ]. Gestational exposures to air pollution have been linked with adverse birth outcomes such as preterm birth, low birth weight, and stillbirth [ 7 , 8 ]; and are further connected to neurodevelopmental effects, effects on childhood respiratory function and lung development, and congenital heart defects [ 9 , 10 , 11 , 12 ]. In recent years, a growing body of literature has examined ways that air pollution affects thyroid function, which plays a critical role in fetal development.

During pregnancy, the thyroid produces a set of hormones that are associated with fetal brain development [ 13 ]. The thyroid is responsible for secreting two major hormones: thyroxine (T4) and triiodothyronine (T3), the release of which is controlled by thyroid- stimulating hormone (TSH) [ 14 ]. During the first trimester, the fetal thyroid gland is developing, causing the fetus to be dependent upon the maternal transfer of T4 [ 13 , 15 ]. Fetal T4 production begins at the end of the first trimester and steadily increases until the end of the third trimester, therefore, thyroid hormone-dependent functions are driven by maternal thyroid hormones during the first two trimesters of gestation [ 13 , 16 ]. Alterations in thyroid function and thyroid hormone ratios in pregnant persons can negatively impact a developing fetus, even contributing to cognitive deficits and reductions in the growth of the child [ 17 , 18 ]. As such, it is important to consider the impacts of air pollution on thyroid function in both the pregnant person and their offspring, including during gestation and the early postnatal period, to identify underlying mechanisms contributing to endocrine disruption and provide an evidence base for protective guidance.

The mechanisms by which air pollutants disrupt the endocrine system have not been sufficiently characterized [ 19 , 20 ]. However, environmental pollutants more broadly disrupt thyroid gland function through thyroid hormone synthesis, metabolism, secretion, and action; primarily by reducing circulating thyroid hormone levels or by disrupting hormone action. Furthermore, environmental pollutants affect the pituitary gland, TSH levels, and iodine absorption (important in thyroid hormone biosynthesis), and act as thyroid hormone receptor agonists [ 21 , 22 , 23 ]. Aside from fetal developmental defects that can arise from hormone fluctuations during pregnancy, disruptions to thyroid function have implications for thyroid-related autoimmune disorders and the development of conditions such as hyper- or hypothyroidism [ 24 ]. Altered thyroid function usually results from genetic predisposition coupled with environmental triggers, namely synthetic chemicals, organic water pollutants, and air pollutants [ 25 , 26 ].

We conducted a systematic literature review to identify effects of prenatal air pollutants exposure on maternal and fetal thyroid function. Several reviews have investigated the association between air pollution exposure and a range of adverse birth outcomes [ 7 , 9 , 10 , 11 , 12 , 27 ]. One review examines air pollution effects on childhood endocrinologic disorders [ 28 ], and two examine air pollution effects on thyroid function generally [ 29 , 30 ]; both of which have broad inclusive criteria for population and thyroid abnormalities yet conduct a very limited assessment of the effects of air pollutants on associated thyroid outcomes. Here, we advance upon these previous reviews by applying the rigorous Navigation Guide Framework [ 31 ] and focusing on prenatal exposure, resulting in a narrowed topical focus that includes more articles and a wider range of pollutants and thyroid outcomes.

Key reports that evaluate policy-relevant science to protect public health presently lack epidemiologic literature on prenatal air pollutant exposure and its impacts on maternal and fetal thyroid function. For example, the Environmental Protection Agency’s 2019 Integrated Science Assessment (ISA) for PM [ 32 ] mentions the potential impact of PM 2.5 on biological pathways for pregnancy and birth outcomes, including effects on fetal thyroid function, in only one sentence citing two studies [ 33 , 34 ], neither of which considers effects on maternal thyroid function. Results of our review may be useful to characterize important air pollution exposure windows during pregnancy and identify concentration-response relationships between prenatal air pollution exposure and adverse thyroid outcomes.

We conducted a systematic literature review using steps adapted from the Navigation Guide Framework described by Johnson et al. [ 31 ]: (1) specify the study question; (2) select the evidence; and (3) rate the quality and strength of evidence.

Development of study question

The objective of this systematic review is to answer the question: How does prenatal exposure to air pollution affect maternal and fetal thyroid function? A PECO (population, exposure, comparator, outcome) statement was developed containing the following components:

  P [population] : pregnant women and fetuses exposed to higher levels of air pollution.

  E [exposure] : ambient air pollution.

  C [comparator] : pregnant women and fetuses exposed to lower levels of air pollution.

  O [outcome] : maternal and fetal thyroid outcomes.

For the purposes of this systematic review, we additionally considered studies that collected outcome assessment measures of neonates when the measurements of thyroid function were recorded shortly after delivery and air pollution exposure was still assigned during the prenatal period; these studies were considered for inclusion as the exposure assessment is focused on the gestational experience and the measurement of thyroid function in the near-immediacy after birth provides some insight into fetal thyroid functioning [ 35 ].

Evidence selection

Search terms and methods.

We used the following search terms to identify admissible literature: prenatal (OR before birth OR pregnant OR pre-birth OR in utero OR gestational OR trimester) AND air pollution (OR nitrogen oxide OR nitrogen dioxide OR particulate matter OR fine particulate matter OR ozone OR traffic-related) AND thyroid (OR endocrine OR thyroid function OR hypothyroidism OR hyperthyroidism OR congenital hypothyroidism OR thyroxine OR triiodothyronine OR thyroid stimulating hormone OR thyrotropin). We conducted a first search on February 22 and 26, 2022 and an updated search on January 25, 2024 using four databases: PubMed [ 36 ], Scopus [ 37 ], ProQuest Environmental [ 38 ], and Cochrane Reviews [ 39 ]. We hand-vetted all reference lists for included studies to incorporate studies that may have been missed in the initial search. Complete lists of search terms and records retrieved for each database during the two search periods are included in Tables  S1 and S2 .

Study selection

Included papers must have been peer-reviewed, published in English, and published from 2017 to the date the search was carried out to be considered in the final analysis. All search results were exported to Covidence [ 40 ]. We first screened titles and abstracts for inclusion criteria, and then reviewed the non-excluded articles in full text. Following full-text review, we excluded studies if they examined animal and not human populations; did not include the outcome, exposure, or population of interest; or did not present novel data. Additionally, we excluded Review, Narrative, or Perspective papers. Two authors (C.O. and E.J.C.) independently screened and reviewed articles for inclusion or exclusion and met to decide on final selection. A third author (S.C.A.) adjudicated if the two authors could not come to a consensus.

When referencing specific results of manuscripts included in this review, we adopt the language used by those manuscripts (e.g., women, females, mothers). In our broader discussions on the implications of such work, we have chosen to use gender-inclusive terms (e.g., pregnant persons, parent, etc.).

Rate the quality and strength of evidence

We evaluated the quality and strength of the evidence by: (1) assessing the “risk of bias” of individual studies, following Johnson et al. [ 31 ]; (2) evaluating the quality of evidence across the selected studies; and (3) rating the strength of the evidence across the breadth of studies.

Risk of bias assessment

We used the Risk of Bias instrument described by Johnson et al. [ 31 ]. Two authors (C.O. and E.J.C.) independently analyzed the risk of bias for each included study and met to decide on final bias designations. A third author (S.C.A.) adjudicated if the two authors could not come to a consensus. Each risk of bias domain was assigned as “low risk,” “probably low risk,” “probably high risk,” “high risk,” or “unclear risk” (not enough information given to provide a clear designation of risk). We applied a protocol which outlined specific instructions and designations for each bias classification to ensure consistency in interpretation (Table  S3 ).

Quality of evidence

We used three ratings to synthesize the overall quality of evidence: (1) “high;” (2) “moderate;” and (3) “low.” We first assigned an initial “moderate” quality rating to the encompassing body of evidence. We then considered evaluation factors via “downgrades” and “upgrades” (Table  S4 ). Possible ratings ranged from 0 (no change from “moderate” quality); -1 (one-level downgrade); -2 (two-level downgrade); +1 (one-level upgrade); or + 2 (two-level upgrade).

Strength of evidence

We rated the overall strength of the body of evidence based on a combination of four considerations: (1) quality of evidence (described in previous section); (2) direction of the effect estimate; (3) confidence in the effect estimate; and (4) other compelling data attributes that may affect the conclusion. We compared the results of the strength of evidence rating to definitions specified in the Johnson et al. [ 31 ] Navigation Guide for “sufficient evidence of toxicity,” “limited evidence of toxicity,” “inadequate evidence of toxicity,” or “evidence of lack of toxicity” (Table  S5 ).

Included studies

Our search recovered 2,057 unique records, and we added one paper identified through hand-vetting the reference lists of each article (Fig.  1 ). After removing duplicates, we screened 1,961 papers and assessed 41 full-text articles for eligibility. Of these 41 articles, 22 were excluded for the following reasons: did not include outcome of interest (11 excluded); did not include exposure of interest (3); Review, Narrative, or Perspective article (5); did not examine the study population of interest (1); was an evaluation of a cohort design (1); and did not present novel data (1).

The included studies encompassed nine countries (Belgium, China, France, Greece, Iran, Israel, Netherlands, Spain, United States) and 736,808 individuals, plus two studies that analyzed 367 cities for which a total sample size was not provided (Table  1 ). The studies ranged in air pollutants measured (e.g., PM 2.5 , NO x , bound metals, etc.) and thyroid outcomes measured (e.g., fluctuations in hormones [TSH, T3, T4], congenital hypothyroidism, hypothyroxinemia). Data collection ranged from 1999 to 2020, and exposure windows ranged from preconception to full pregnancy term.

PRISMA Diagram of the literature search and screening process

Measuring exposure

The studies used a diverse range of methods to measure exposure (Table  S6 ). Of the 19 studies, 12 used residential geocoding to improve spatial accuracy of exposure estimates (all except 37–43). Four studies utilized fixed-monitoring networks within their locality [ 46 , 50 , 51 , 52 ], 12 studies used modeling (e.g., land-use regression, dispersion) or machine learning methods [ 33 , 41 , 43 , 44 , 44 , 48 , 49 , 53 , 54 , 55 , 56 , 57 , 58 ], and three studies used a combination of fixed-monitoring network data and pollutant modeling [ 42 , 45 , 47 ]. Two studies used particle sampling, including high volume aerosol and radial passive sampling [ 47 ] and filter capture of particulates [ 51 ]; and one study conducted personal monitoring on a sub cohort group of their study population [ 58 ].

PM 2.5 was the pollutant measured most frequently, incorporated in 18 of the 19 included studies (all except 40). Nine studies incorporated exposure estimates for PM 10 [ 41 , 42 , 43 , 45 , 46 , 51 , 52 , 53 , 56 ] and eight studies used exposure estimates for NO 2 [ 42 , 44 , 45 , 46 , 47 , 50 , 51 , 57 ]. Additionally, two studies included measurements of PM 2.5 - bound metals and inorganic constituents [ 51 , 58 ] and one study assessed six constituents of PM 2.5 (i.e., OM, BC, SO 4 2− , NO 3 − , NH 4 + , soil dust) [ 54 ]. Other pollutants measured in the studies included coarse particulate matter (PM 2.5−10 ), ozone (O 3 ), nitrogen oxides (NO x ), sulfur dioxide (SO 2 ), and carbon monoxide (CO).

Exposure windows

Studies varied with respect to exposure windows. Five studies assessed exposure during the first trimester only [ 42 , 43 , 51 , 54 , 56 ], no studies assessed exposure during second trimester only, two studies assessed exposure during third trimester only [ 33 , 41 ], and seven studies assessed exposure during the full gestation period [ 44 , 45 , 47 , 49 , 50 , 52 , 55 ]. Three studies looked at exposure during the period prior to gestation, known as preconception [ 46 , 48 , 53 ].

Measuring outcome

Included studies measured TSH, FT4, FT3, FT4/FT3 ratio, TT4, hypothyroxinemia, hypothyroidism, and congenital hypothyroidism (CHT) in either pregnant women [ 42 , 43 , 46 , 48 , 51 , 53 , 56 , 57 , 58 ], their fetuses [ 49 , 55 ], their neonates [ 41 , 44 , 45 , 47 , 50 , 52 ], or as a paired analysis of both maternal and fetal/neonatal outcomes [ 33 , 54 ]. Studies defined hypothyroxinemia as FT4 concentrations in the lower 2.5th to 5th percentile (or < 12.25 pg/L) of the population despite a normal TSH level [ 42 , 57 ], hypothyroidism as TSH concentrations > 4 mU/L and FT4 concentrations below the lower limit of the reference range (0.93–1.70 ng/dL) [ 53 ], and congenital hypothyroidism as a concentration of TSH higher than 10–20 µIU/ml in double testing and confirmed diagnosis by a pediatric endocrinologist based on serum thyroid function tests [ 44 , 50 , 52 ].

For studies solely measuring thyroid outcomes in fetal/neonatal populations (Table  S6 ), newborn heel-prick was the method used most frequently, employed in four studies [ 41 , 44 , 45 , 47 ], followed by cord blood collection in two studies [ 49 , 55 ], and whole-blood collection in two studies [ 50 , 52 ]. Sample collection time frames ranged from immediately after delivery [ 49 ] to within seven days after birth [ 50 , 52 ]. Most studies collected samples within 72 h after birth [ 41 , 44 , 45 , 47 ].

For studies solely measuring thyroid outcomes in maternal populations (Table  S6 ), blood samples were collected in six of the studies [ 43 , 48 , 51 , 56 , 57 , 58 ] and maternal serum was sampled in one study [ 42 ]. Ilias et al. [ 46 ] identified women who were diagnosed with hypothyroidism during pregnancy and retrospectively analyzed air quality data during their gestation period. Sample collection time frames ranged from within the first 14 weeks of pregnancy [ 42 , 51 , 53 , 58 ] to second trimester [ 43 , 46 , 57 ].

Janssen et al. [ 33 ] and Wang et al. [ 54 ] assessed outcomes in mother-child pairs (Table  S6 ). Janssen et al. [ 33 ] used umbilical cord blood samples for the fetal population, collected immediately after delivery, and blood samples for the maternal population, collected one day after delivery. Wang et al. [ 54 ] utilized newborn heel-prick samples to assess neonatal thyroid function, collected within 72 h after birth, and maternal serum samples collected during the second trimester.

Maternal and fetal/neonatal thyroid function

Main study findings for each study including whether there was evidence of altered maternal or fetal/neonatal thyroid function, the outcome assessed, and the directionality of the association can be found in Table  2 . Of the outcomes examined, TSH levels were evaluated most frequently, in 13 of the 19 studies (all except 39,40,42,45,48,54). Of the studies that assessed prenatal air pollution exposure and maternal TSH levels, two studies found a positive association with PM 2.5 [ 46 , 58 ] and seven studies found no association with PM 2.5 [ 33 , 42 , 43 , 48 , 51 , 56 , 57 ]. Five studies found no association with PM 10 [ 42 , 43 , 46 , 51 , 56 ] and four studies found no statistically significant association with NO 2 exposure [ 42 , 46 , 51 , 57 ]. Of the studies that assessed prenatal air pollution exposure to PM 2.5 and fetal/neonatal TSH levels, results were mixed: three studies found a positive association [ 41 , 49 , 55 ], one study found an inverse association [ 33 ], and one study found no association [ 54 ].

Two studies evaluated prenatal exposure to air pollution and neonatal total thyroxine (TT4) measure, and both observed a positive association between increases in PM 2.5 exposure and higher TT4 levels [ 45 , 47 ]. The same studies also observed no significant association with NO 2 .

Results were not congruent amongst studies that assessed PM 2.5 exposure and maternal FT3 levels. Three studies found no association [ 33 , 56 , 58 ], one study found a positive association [ 48 ], and one study found an inverse association [ 50 ]. Results were similarly inconsistent amongst studies that assessed PM 2.5 and fetal FT3 concentrations: one study found positive association [ 33 ], and one study found no association [ 55 ].

Free thyroxine (FT4) levels were examined in nine studies [ 33 , 43 , 48 , 51 , 54 , 55 , 56 , 57 , 58 ]. Similar to the results of FT3, there was inconsistency amongst findings. In studies that evaluated PM 2.5 exposure and changes to maternal FT4 concentrations, one study found a positive association [ 43 ], five studies found an inverse association [ 48 , 54 , 56 , 57 , 58 ], and one study found no association [ 33 ]. In studies that evaluated PM 2.5 exposure and changes to fetal FT4 concentrations, one study found an inverse association [ 33 ], and one study found no association [ 55 ].

CHT and hypothyroxinemia

Additionally, CHT was investigated in three studies [ 44 , 50 , 52 ] and maternal hypothyroxinemia was evaluated in two studies [ 42 , 57 ]. For studies that evaluated CHT: two studies found a positive association between NO 2 exposure and odds of developing CHT [ 44 , 50 ], one study observed a positive association between PM 2.5 exposure and risk of CHT, as well as no statistically significant association between PM 10 and CHT [ 52 ], and one study found no association between PM 2.5−10 exposure and odds of developing CHT [ 44 ]. For studies that evaluated maternal hypothyroxinemia: both found a positive association between increased exposure to PM 2.5 and increased odds of hypothyroxinemia as well as no association between exposure to NO 2 and odds of hypothyroxinemia [ 42 , 57 ].

FT4/FT3 ratio

Air pollution exposure and its effect on the FT4/FT3 ratio was explored in five studies [ 33 , 48 , 51 , 56 , 58 ]. Of the studies that looked at the association between PM 2.5 exposure and the FT4/FT3 ratio concentrations in maternal samples, results differed. Two studies found no association [ 33 , 51 ], and three studies found an inverse association [ 48 , 56 , 58 ]. Only one study assessed the FT4/FT3 ratio in fetal samples [ 33 ]; authors found a significant inverse association between increased PM 2.5 exposure and decreased FT4/FT3 ratio concentration in cord blood.

Critical windows of exposure

Of the seven studies that assessed exposure during the full gestation period, three identified critical windows of exposure based on evidence of a significant association [ 44 , 45 , 47 ]. Harari-Kremer et al. [ 44 ] identified the third trimester as a sensitive window for exposure to NO 2 and NO x and associated odds of CHT. Howe et al. [ 45 ] identified gestation months 3–7 (strongest association observed at month five) as critical for exposure to PM 2.5 and effects on TT4 concentration, and gestation months 1–8 (strongest effect observed at month one) as critical for exposure to PM 10 and effects on TT4 concentration. Irizar et al. [ 47 ] identified three windows of sensitivity for PM 2.5 exposure and effects on TT4 concentration: the preconception period, gestation weeks 12–17, and gestation weeks 31–37. The remaining four studies that assessed the full gestation period focused their analysis on the spatial aspects of exposure [ 49 ] or on the level of exposure [ 50 , 52 , 55 ], and therefore did not assess critical windows of exposure.

The included studies had a moderate risk of bias. All studies were rated as ‘low risk’ or ‘probably low risk’ for selective outcome reporting, conflict of interest, recruitment strategy, and other biases (Fig.  2 ). Almost all of the studies were determined to have an ‘unclear’ level of risk for blinding due to the insufficiency of evidence provided to make a clear designation of risk. Risk of bias for exposure assessment was determined as ‘high risk’ for almost all studies (63%), as the methods were deemed not robust (e.g., did not geocode to participant residence, did not address participant mobility, or only used fixed-site monitoring). All studies were rated as ‘probably high risk’ of bias for exposure assessment at the start due to the inability of studies to account for the full exposure profile, including exposures at work, during travel, etc. All studies were rated as ‘high risk’ or ‘probably high risk’ for confounding as it is anticipated that the lack of accounting for important potential confounders is expected to introduce some bias. All studies were rated ‘probably high risk’ of bias for confounding at the start due to the inability to adjust for pollutants not included in the studies’ analysis, including PM 2.5 -bound endocrine disruptors, polychlorinated biphenyls, heavy metals, and others, that could be associated with air pollution and thyroid function. Additionally, if a study did not account for two or more of the important potential confounders listed in Table  S3 , a ‘high risk’ designation was assigned.

Risk of bias designations for each included study. Table  S7 includes the rationale for the designations for each study

Quality of the body of evidence

We assessed the quality of the body of evidence using the upgrading and downgrading factors described in Table  S4 . This approach was only applied to studies that evaluated exposure to PM 2.5 because this was the pollutant addressed in nearly all studies (95%). Other pollutants were not included as evaluative factors in enough studies to be able to assess the quality of evidence across the body of literature. Generally, the studies were individually assigned a moderate risk of bias, as ‘low risk’ or ‘probably low risk’ was assigned for most bias categories, and ‘high risk’ or ‘probably high risk’ was similarly assigned for exposure assessment and confounding biases.

The findings across studies were inconsistent, resulting in a -2 downgrading of the evidence. For example, there were incongruent relationships in three or more pollutant and outcome pairs in similar populations (e.g., three studies found no association between PM 2.5 exposure and FT3 concentration, one study found a positive association between increased PM 2.5 exposure and increased FT3 concentration, and one study found an inverse association between increased PM 2.5 exposure and decreased FT3 concentration). There was a consistent positive concentration-response in ten or more of the studies which resulted in a + 2 upgrading of the quality of evidence. Notably, Howe et al. [ 45 ] and Irizar et al. 47 ] identified a positive association between increases in exposure to PM 2.5 and increases in neonatal TT4 levels, and Ghassabian et al. [ 42 ] and Zhao et al. [ 57 ] observed a positive relationship between increased exposure to PM 2.5 and odds of developing hypothyroxinemia. Because we upgraded the body of literature based on concentration-response relationships and downgraded based on inconsistency of the data across studies and risk of bias, we deemed the overall quality of evidence to be “ Low ” (Table  3 ).

Strength of the body of evidence

Our strength of the body of evidence considerations included the quality of the body of evidence, direction of the effect estimate, confidence in the effect estimate, and other compelling attributes of the data. The overall quality of the body of evidence was rated as low based on the upgrading factor of concentration-response relationships and the downgrading factors of inconsistency in results and risk of bias. Based on our analysis and interpretation of the evidence, we conclude that there is limited evidence of an association between prenatal air pollution exposure and maternal and fetal thyroid function. Chance, bias, and confounding cannot be ruled out with reasonable confidence as the relationship is constrained by inconsistency of findings across individual studies. As more research is made available, it is possible that the observed effect could change.

We conducted a systematic review of human population health studies to examine evidence for associations between prenatal air pollution exposure and maternal and fetal thyroid outcomes. We found limited evidence for associations based on 19 studies examining a range of air pollutants (PM 2.5 , PM 10 , PM 2.5−10 , NO 2 , O 3 , NO x , CO, SO 2 , PM 2.5 -bound metals and inorganic constituents, OM, BC, SO 4 2− , NO 3 − , NH 4 + , soil dust) and maternal and fetal/neonatal thyroid outcomes (congenital hypothyroidism, hypothyroxinemia, hypothyroidism, FT3, FT4, TT4, TSH, and FT4/FT3 ratios). The overall risk of bias across the studies was rated as moderate and the quality of the body of evidence was rated as low .

Among the pollutants, PM 2.5 was most consistently and significantly associated with differences in fetal/neonatal and maternal thyroid hormone concentrations, with 17 (89%) of the included studies finding an association. To a lesser extent, traffic-related air pollutants, such as NO 2 had significant effects on thyroid outcomes. There was less evidence to support that exposure to other air pollutants, such as PM 10 , NO x, CO, SO 2 , O 3 , and others, contributed to alterations in thyroid hormone levels in both pregnant persons and their children. In terms of health outcomes, we found positive associations between increased exposure to PM 2.5 and higher odds of hypothyroxinemia and increased neonatal TT4 concentration [ 42 , 45 , 47 , 57 ]. Additional studies found a positive association between increased exposure to NO 2 and odds of congenital hypothyroidism [ 44 , 50 ]. Associations between air pollution and TSH, FT4, FT3, and the FT3/FT4 ratio levels were inconsistent.

Directional effect differences associated with PM 2.5 -bound metals may be in part due to the underlying biological mechanisms in exposure-response pathways [ 59 , 60 , 61 ]. Prior research has shown that exposure to air pollution contributes to alterations in maternal thyroid function through mechanisms such as hormone synthesis, transport, metabolism, and gene regulation [ 62 ]. And, some research, including from some studies incorporated in this review, has suggested that air pollutants disrupt fetal or neonatal hormone concentrations through changes in enzymes associated with hormone synthesis, the obstruction of hormone metabolism, or by impeding the placental transfer of thyroid hormones from mother to fetus [ 33 , 44 , 45 ]. Aside from the effect that different pollutants and pollutant-bound metals may have on hormones, differences in the directional associations of thyroid hormone concentrations may at least be in part explained by the point of gestation at which the serum or blood sample was taken. For example, the FT4/FT3 ratio is a metabolic indicator of how well the body is able to convert the T4 hormone to the T3 hormone [ 63 ]. As mentioned previously, depending on the gestational time frame, the fetus is either more or less dependent on the maternal production of T4 [ 13 , 15 , 16 ]. Thus, differences in gestational sampling windows across the studies, coupled with biological process differences in exposure-response pathways, may explain some of the variation in thyroid hormone concentration findings.

At the time of this review, a critical window of exposure for air pollution and effects on maternal and fetal thyroid function has not been established. Critical windows, also referred to as sensitive periods, are representative of developmental periods when an organism is susceptible to changes in response to environmental stimuli, and thus are important to characterize to better understand the underlying biological mechanisms that contribute to adverse outcomes [ 64 ]. Results from this review support the need for further research that aims to identify critical windows of exposure to better understand how air pollution affects the biological processes that contribute to altered thyroid functioning.

The findings of this review support findings from other reviews not included in this analysis, suggesting that prenatal exposure to air pollution may be associated with altered thyroid functioning in pregnant persons and their fetuses/neonates. Liu et al. [ 29 ] conducted a pooled analysis of a subgroup of included studies that assessed pregnancy exposure windows (primarily in the first trimester), finding that PM 2.5 was associated with an inverse relationship with FT4 concentration; in our review, one study found a positive association, six studies found an inverse association, and two studies found no statistically significant association. Rohani et al. [ 30 ], a preprint, non-peer reviewed article, conducted a pooled assessment for maternal hypothyroxinemia and found that exposure to PM 2.5 was associated with increased odds of maternal hypothyroxinemia but exposure to NO 2 was not; this is consistent with findings of our review.

Location was the primary driver of exposure and was indicative of types of pollutants analyzed (PM 10 , PM 2.5 , NO 2 , NO x , O 3 , and others), exposure assessment methods used, and level of exposure. For example, Harari-Kremer et al. [ 44 ] was only able to capture NO 2 and NO x exposure data for a subset of 54% of their study population due to data availability. Spatial variability in level of exposure may be attributed to residential proximity to high emitting sources of air pollutants, such as highways. While exposure profiles were characterized by geocoding to residential address in twelve (63%) studies, geocoding to residential zip code in one study, and assigned based on proximity to fixed-site monitoring data in the remaining six studies, this does not capture the full exposure profile and does not characterize internal dose. The large portion of included studies that were conducted in China (11 of 19; or 58%), where pollutant concentrations were higher than in studies conducted in other parts of the world, could have affected study results (e.g. if the exposure-response relationship is non-linear).

The outcomes related to thyroid function evaluated in these studies are known to be multifactorial and complex. Alterations to maternal thyroid function can be associated with factors such as autoimmunity, iodine deficiency, and physical characteristics such as high body mass index (BMI) [ 65 ]. Assessing thyroid hormone function during pregnancy can be further complicated due to the natural hormonal and physiological changes that pregnant persons undergo, as well as stress put on the maternal thyroid during this time [ 66 ]. The compilation of the results from studies included in this review present some evidence that in addition to the aforementioned associations, prenatal exposures to air pollution may contribute to adverse outcomes related to maternal and fetal thyroid function. Though there was heterogeneity in findings amongst several pollutant and outcome pairs in similar populations, we consider any alterations in thyroid hormone levels (both increases and decreases) as adversely impactful due to established implications such as fetal neurodevelopmental defects, and the development of thyroid-related autoimmune disorders and conditions (e.g., hyperthyroidism).

This review had several strengths. Including studies from multiple countries, some of which have very large sample sizes (e.g., hundreds of thousands of people) provides a global perspective to both exposure and outcome; establishing that adverse maternal and fetal/neonatal thyroid outcomes are not isolated to air pollution exposures in a particular region but occur globally. Furthermore, studies included in this analysis measured health outcomes objectively (either pulled from medical records or registries, or collected and analyzed during the study period), which limited outcome related self-report bias in the analyses. However, there are several important limitations of this review. Including articles only written in English may have omitted important results from additional studies, though multiple studies from non-English speaking countries were included. The primary limitation of this review stems from the breadth of pollutants, outcomes, and populations in included studies, which prohibited us from being able to draw comparative conclusions across the body of literature. For example, we were only able to consider upgrading and downgrading factors for PM 2.5 due to the limited number of studies that addressed other pollutants, and were unable to look at the quality of evidence for fetal, neonatal, and maternal thyroid function separately; it would be reasonable expect that additional literature could increase comparability and elucidate differences in direction and magnitude of effect estimates for individual air pollutant and thyroid outcome combinations in distinct populations. Additionally, a limiting factor in the body of literature is that few studies address important confounding factors that are associated with air pollution and/or thyroid hormone outcomes; some studies collected covariate information through self-reported questionnaires, which could introduce bias.

Because there is some possibility that differences in study outcomes are driven by the diverse approaches used to measure exposures and outcomes across the body of literature, future research should seek to enhance both exposure and outcome assessment to reduce potential sources of study heterogeneity and obtain more robust conclusions. Exposure assessment methods could be improved by conducting personal monitoring, which is considered the gold standard of exposure assessment, though this could pose cost and logistical constraints that lead to reduced sample size or study periods. While ground monitoring stations offer an accurate picture of exposure at the earth’s surface, they only do so for the area in the immediate vicinity. Because these stations are oftentimes spatially distant, and in some regions of the world nonexistent, satellite remote sensing data and modeling tools offer an opportunity to fill in gaps in exposure estimates. Therefore, we strongly recommend that future work integrate satellite, model, and monitor pollutant datasets to establish exposure profiles. Outcome assessment methods can be improved by measuring multiple thyroid hormones (TT4, FT4, FT3, TSH) and measuring outcomes in both the pregnant person and their offspring. The thyroid system is extremely complex, and even more challenging to study during pregnancy due to the changes that it undergoes during this time, therefore, the thorough collection of measurements would be helpful to understand the intricacies of exposure and outcome during this critical period. Additionally, this research could be enhanced by evaluating both exposure and outcome throughout term pregnancy, as opposed to only evaluating at points in time or during specific trimesters to provide a more complete picture of how the thyroid is affected during gestation and explore whether critical exposure windows exist for exposure to air pollution and altered thyroid function. Thus, we recommend future studies leverage longitudinal designs as opposed to cross-sectional evaluations; thyroid disorders tend to develop over longer periods of prolonged stress and therefore a cross-sectional approach may miss the full spectrum of, and the individual variability of, air pollution exposures and associated thyroid outcomes.

While a significant portion of included studies in this review present findings that suggest prenatal exposure to air pollutants may affect maternal and fetal/neonatal thyroid function, using the objective framework of the Navigation Guide we found the body of evidence to be both limited and low quality. The findings from this review, specifically prenatal exposure to PM 2.5 and its association with altered maternal and fetal/neonatal thyroid function, add to the growing body of literature on how air pollution affects pregnant persons and their developing fetuses. Future research should seek to enhance exposure and outcome assessment methods to reduce study heterogeneity and gain a better understanding of the nuanced complexities between prenatal exposure to air pollution and thyroid function. Furthermore, future research should focus on establishing critical windows of exposure to air pollution and associated impacts on thyroid function.

Data availability

No datasets were generated or analysed during the current study.

Abbreviations

Particulate matter

Nitrogen dioxide

Chronic obstructive pulmonary disease

World Health Organization

Triiodothyronine

Thyroid-stimulating hormone

Particulate matter of 2.5 microns

Integrated Science Assessment

Population, Exposure, Control, Outcome

Nitrogen oxides

Free triiodothyronine

Free thyroxine

Total thyroxine

Congenital hypothyroidism

Particulate matter of 10 microns

Particulate matter of 2.5–10 microns

Carbon monoxide

Sulfur dioxide

Phosphorous

Organic matter

Black carbon

Land-use regression

Brauer M, Roth GA, Aravkin AY, Zheng P, Abate KH, Abate YH et al. Global burden and strength of evidence for 88 risk factors in 204 countries and 811 subnational locations, 1990–2021: a systematic analysis for the Global Burden of Disease Study 2021. The Lancet [Internet]. 2024 May [cited 2024 Jun 28];403(10440):2162–203. https://linkinghub.elsevier.com/retrieve/pii/S0140673624009334

Health Effects Institute. State of global air 2024 [Internet]. https://www.stateofglobalair.org/resources/report/state-global-air-report-2024

WHO global air. quality guidelines: particulate matter (PM2.5 and PM10), ozone, nitrogen dioxide, sulfur dioxide and carbon monoxide. Executive summary [Internet]. p. 4. https://iris.who.int/bitstream/handle/10665/345334/9789240034433-eng.pdf

Sedgh G, Singh S, Hussain R. Intended and unintended pregnancies worldwide in 2012 and recent trends. Stud Fam Plann [Internet]. 2014 Sep [cited 2024 Jun 29];45(3):301–14. https://doi.org/10.1111/j.1728-4465.2014.00393.x

World Health Organization. Billions of people still breathe unhealthy air: new WHO data [Internet]. 2022 [cited 2024 Jun 13]. https://www.who.int/news/item/04-04-2022-billions-of-people-still-breathe-unhealthy-air-new-who-data

Bai W, Li Y, Niu Y, Ding Y, Yu X, Zhu B et al. Association between ambient air pollution and pregnancy complications: A systematic review and meta-analysis of cohort studies. Environ Res [Internet]. 2020 Jun [cited 2024 Aug 20];185:109471. https://linkinghub.elsevier.com/retrieve/pii/S0013935120303649

Bekkar B, Pacheco S, Basu R, DeNicola N. Association of air pollution and heat exposure with preterm birth, low birth weight, and stillbirth in the US: a systematic review. JAMA Netw Open [Internet]. 2020 [cited 2024 Jun 28];3(6):e208243–e208243. https://jamanetwork.com/journals/jamanetworkopen/article-abstract/2767260

Kuehn L, McCormick S. Heat Exposure and Maternal Health in the Face of Climate Change. Int J Environ Res Public Health [Internet]. 2017 Jul 29 [cited 2024 Jun 29];14(8):853. https://www.mdpi.com/1660-4601/14/8/853

Hehua Z, Qing C, Shanyan G, Qijun W, Yuhong Z. The impact of prenatal exposure to air pollution on childhood wheezing and asthma: a systematic review. Environ Res [Internet]. 2017 Nov [cited 2024 Jun 29];159:519–30. https://linkinghub.elsevier.com/retrieve/pii/S0013935117313841

Hu CY, Huang K, Fang Y, Yang XJ, Ding K, Jiang W et al. Maternal air pollution exposure and congenital heart defects in offspring: a systematic review and meta-analysis. Chemosphere [Internet]. 2020 Aug [cited 2024 Jun 29];253:126668. https://linkinghub.elsevier.com/retrieve/pii/S0045653520308614

Korten I, Ramsey K, Latzin P. Air pollution during pregnancy and lung development in the child. Paediatr Respir Rev [Internet]. 2017 Jan [cited 2024 Jun 29];21:38–46. https://linkinghub.elsevier.com/retrieve/pii/S1526054216300823

Volk HE, Perera F, Braun JM, Kingsley SL, Gray K, Buckley J et al. Prenatal air pollution exposure and neurodevelopment: a review and blueprint for a harmonized approach within ECHO. Environ Res [Internet]. 2021 May [cited 2024 Jun 29];196:110320. https://linkinghub.elsevier.com/retrieve/pii/S0013935120312172

Burrow GN, Fisher DA, Larsen PR. Maternal and fetal thyroid function. N Engl J Med [Internet]. 1994 Oct 20 [cited 2024 Jun 28];331(16):1072–8. https://doi.org/10.1056/NEJM199410203311608

Brent GA. Mechanisms of thyroid hormone action. J Clin Invest [Internet]. 2012 Sep 4 [cited 2024 Jun 28];122(9):3035–43. http://www.jci.org/articles/view/60047

De Morreale G, Obregon M, Escobar Del Rey F. Role of thyroid hormone during early brain development. Eur J Endocrinol [Internet]. 2004 Nov 1 [cited 2024 Jun 28];U25–37. https://academic.oup.com/ejendo/article/151/Supplement_3/U25/6694487

Contempré B, Jauniaux E, Calvo R, Jurkovic D, Campbell S, De Escobar GM. Detection of thyroid hormones in human embryonic cavities during the first trimester of pregnancy. J Clin Endocrinol Metab [Internet]. 1993 Dec [cited 2024 Jun 28];77(6):1719–22. https://doi.org/10.1210/jcem.77.6.8263162

Korevaar TIM, Muetzel R, Medici M, Chaker L, Jaddoe VWV, De Rijke YB et al. Association of maternal thyroid function during early pregnancy with offspring IQ and brain morphology in childhood: a population-based prospective cohort study. Lancet Diabetes Endocrinol [Internet]. 2016 Jan [cited 2024 Jun 29];4(1):35–43. https://linkinghub.elsevier.com/retrieve/pii/S2213858715003277

Medici M, Timmermans S, Visser W, De Muinck Keizer-Schrama SMPF, Jaddoe VWW, Hofman A et al. Maternal thyroid hormone parameters during early pregnancy and birth weight: the generation R study. J Clin Endocrinol Metab [Internet]. 2013 Jan [cited 2024 Jun 29];98(1):59–66. https://doi.org/10.1210/jc.2012-2420

Tanda M, Piantanida E, Lai A, Lombardi V, Dalle Mule I, Liparulo L et al. Thyroid autoimmunity and environment. Horm Metab Res [Internet]. 2009 Jun [cited 2024 Jun 29];41(06):436–42. http://www.thieme-connect.de/DOI/DOI?10.1055/s-0029-1215568

Prummel M, Strieder T, Wiersinga W. The environment and autoimmune thyroid diseases. Eur J Endocrinol [Internet]. 2004 May 1 [cited 2024 Jun 29];150(5):605–18. https://academic.oup.com/ejendo/article/150/5/605/6694370

Brent GA, Braverman L, Zoeller T. Thyroid health and the environment. thyroid [Internet]. 2007 Sep [cited 2024 Jun 28];17(9):807–9. https://www.liebertpub.com/doi/ https://doi.org/10.1089/thy.2007.1514

Pearce EN, Braverman LE. Environmental pollutants and the thyroid. Best Pract Res Clin Endocrinol Metab [Internet]. 2009 Dec [cited 2024 Jun 29];23(6):801–13. https://linkinghub.elsevier.com/retrieve/pii/S1521690X0900075X

Zoeller TR, Dowling ALS, Herzig CTA, Iannacone EA, Gauger KJ, Bansal R. Thyroid hormone, brain development, and the environment. Environ Health Perspect [Internet]. 2002 Jun [cited 2024 Jun 29];110(suppl 3):355–61. https://doi.org/10.1289/ehp.02110s3355

Murthy MB, Murthy BK. Thyroid disruptors and their possible clinical implications. Indian J Pharmacol. 2012;44(4):542–3.

Article   CAS   Google Scholar  

Burek CL, Talor MV. Environmental triggers of autoimmune thyroiditis. J Autoimmun [Internet]. 2009 Nov [cited 2024 Jun 28];33(3–4):183–9. https://linkinghub.elsevier.com/retrieve/pii/S0896841109001152

Tomer Y, Huber A. The etiology of autoimmune thyroid disease: a story of genes and environment. J Autoimmun [Internet]. 2009 May [cited 2024 Jun 29];32(3–4):231–9. https://linkinghub.elsevier.com/retrieve/pii/S0896841109000341

Hu CY, Gao X, Fang Y, Jiang W, Huang K, Hua XG et al. Human epidemiological evidence about the association between air pollution exposure and gestational diabetes mellitus: systematic review and meta-analysis. Environ Res [Internet]. 2020 Jan [cited 2024 Jun 29];180:108843. https://linkinghub.elsevier.com/retrieve/pii/S0013935119306401

Heo YJ, Kim HS. Ambient air pollution and endocrinologic disorders in childhood. Ann Pediatr Endocrinol Metab [Internet]. 2021 Sep 30 [cited 2024 Jun 29];26(3):158–70. http://e-apem.org/journal/view.php?doi=10.6065/apem.2142132.066

Liu J, Zhao K, Qian T, Li X, Yi W, Pan R et al. Association between ambient air pollution and thyroid hormones levels: a systematic review and meta-analysis. Sci Total Environ [Internet]. 2023 Dec [cited 2024 Jun 29];904:166780. https://linkinghub.elsevier.com/retrieve/pii/S0048969723054050

Rohani F, Rezayat AA, Rohani B, Liaghat A, Najafi S, Jafari N et al. Air pollution and thyroid abnormalities: systematic review and meta-analysis [Internet]. 2023 [cited 2024 Jun 29]. https://www.researchsquare.com/article/rs-3021590/v1

Johnson PI, Sutton P, Atchley DS, Koustas E, Lam J, Sen S et al. The navigation guide—evidence-based medicine meets environmental health: systematic review of human evidence for PFOA effects on fetal growth. Environ Health Perspect [Internet]. 2014 Oct [cited 2024 Jun 29];122(10):1028–39. https://doi.org/10.1289/ehp.1307893

U.S. EPA. Integrated science assessment (ISA) for particulate matter [Internet]. 2019 Dec. https://assessments.epa.gov/risk/document/&deid=347534

Janssen BG, Saenen ND, Roels HA, Madhloum N, Gyselaers W, Lefebvre W et al. Fetal thyroid function, birth weight, and in Utero exposure to fine particle air pollution: a birth cohort study. Environ Health Perspect [Internet]. 2017 Apr [cited 2024 Jun 29];125(4):699–705. https://doi.org/10.1289/EHP508

Lavigne E, Ashley-Martin J, Dodds L, Arbuckle TE, Hystad P, Johnson M et al. Air pollution exposure during pregnancy and fetal markers of metabolic function: the MIREC study. Am J Epidemiol [Internet]. 2016 May 1 [cited 2024 Jun 29];183(9):842–51. https://doi.org/10.1093/aje/kwv256

Seth A, Rashmi M, Bhakhri B, Sekri T. Neonatal thyroid screening: Relationship between cord blood thyroid stimulating hormone levels and thyroid stimulating hormone in heel prick sample on 4th to 7th day-of-life. Indian J Endocrinol Metab [Internet]. 2014 [cited 2024 Sep 11];18(1):125. https://doi.org/10.4103/2230-8210.126599

PubMed [Internet]. https://pubmed.ncbi.nlm.nih.gov/

Scopus [Internet]. https://www-scopus-com.proxygw.wrlc.org/search/form.uri?display=basic#basic

ProQuest Environmental [Internet]. https://www.proquest.com/

Cochrane Reviews [Internet]. https://www.cochranelibrary.com/

Covidence. [Internet]. https://www.covidence.org

Chamot S, Al-Salameh A, Petit P, Bonneterre V, Cancé C, Decocq G et al. Does prenatal exposure to multiple airborne and tap-water pollutants increase neonatal thyroid-stimulating hormone concentrations? Data from the Picardy region, France. Sci Total Environ [Internet]. 2023 Dec [cited 2024 Jun 29];905:167089. https://linkinghub.elsevier.com/retrieve/pii/S0048969723057169

Ghassabian A, Pierotti L, Basterrechea M, Chatzi L, Estarlich M, Fernández-Somoano A et al. Association of exposure to ambient air pollution with thyroid function during pregnancy. JAMA Netw Open [Internet]. 2019 Oct 16 [cited 2024 Jun 29];2(10):e1912902. https://jamanetwork.com/journals/jamanetworkopen/fullarticle/2752988

Gong Y, Zhao Y, Zhang X, Zhao X, Chang H, Huang J et al. Ambient particulate matter, maternal thyroid function, and birth weight: a mediation analysis. Ecotoxicol Environ Saf [Internet]. 2023 Oct [cited 2024 Jun 29];264:115420. https://linkinghub.elsevier.com/retrieve/pii/S0147651323009247

Harari-Kremer R, Calderon-Margalit R, Korevaar TIM, Nevo D, Broday D, Kloog I et al. Associations between prenatal exposure to air pollution and congenital hypothyroidism. Am J Epidemiol [Internet]. 2021 Dec 1 [cited 2024 Jun 29];190(12):2630–8. https://academic.oup.com/aje/article/190/12/2630/6310595

Howe CG, Eckel SP, Habre R, Girguis MS, Gao L, Lurmann FW et al. Association of prenatal exposure to ambient and traffic-related air pollution with newborn thyroid function: findings from the children’s health study. JAMA Netw Open [Internet]. 2018 Sep 14 [cited 2024 Jun 29];1(5):e182172. http://jamanetworkopen.jamanetwork.com/article.aspx?doi=10.1001/jamanetworkopen.2018.2172 .

Ilias I, Kakoulidis I, Togias S, Stergiotis S, Michou A, Lekkou A et al. Atmospheric pollution and thyroid function of pregnant women in Athens, Greece: a pilot study. Med Sci [Internet]. 2020 Apr 4 [cited 2024 Jun 29];8(2):19. https://www.mdpi.com/2076-3271/8/2/19 .

Irizar A, Txintxurreta A, Molinuevo A, Jimeno-Romero A, Anabitarte A, Álvarez JI et al. Association between prenatal exposure to air pollutants and newborn thyroxine (T4) levels. Environ Res [Internet]. 2021 Jun [cited 2024 Jun 29];197:111132. https://linkinghub.elsevier.com/retrieve/pii/S0013935121004266

Li J, Liao J, Hu C, Bao S, Mahai G, Cao Z et al. Preconceptional and the first trimester exposure to PM2.5 and offspring neurodevelopment at 24 months of age: Examining mediation by maternal thyroid hormones in a birth cohort study. Environ Pollut [Internet]. 2021 Sep [cited 2024 Jun 29];284:117133. https://linkinghub.elsevier.com/retrieve/pii/S0269749121007156

Nourouzi Z, Chamani A. Characterization of ambient carbon monoxide and PM 2.5 effects on fetus development, liver enzymes and TSH in Isfahan City, central Iran. Environ Pollut [Internet]. 2021 Dec [cited 2024 Jun 29];291:118238. https://linkinghub.elsevier.com/retrieve/pii/S0269749121018200

Qi C, Shang L, Yang W, Huang L, Yang L, Xin J et al. Maternal exposure to O3 and NO2 may increase the risk of newborn congenital hypothyroidism: a national data-based analysis in China. Environ Sci Pollut Res [Internet]. 2021 Jul [cited 2024 Jun 29];28(26):34621–9. https://doi.org/10.1007/s11356-021-13083-6

Qiu L, Shen W, Ye C, Wu J, Zheng S, Lou B et al. Association of exposure to PM2.5-bound metals with maternal thyroid function in early pregnancy. Sci Total Environ [Internet]. 2022 Mar [cited 2024 Jun 29];810:151167. https://linkinghub.elsevier.com/retrieve/pii/S0048969721062458

Shang L, Huang L, Yang W, Qi C, Yang L, Xin J et al. Maternal exposure to PM2.5 may increase the risk of congenital hypothyroidism in the offspring: a national database based study in China. BMC Public Health [Internet]. 2019 Dec [cited 2024 Jun 29];19(1):1412. https://doi.org/10.1186/s12889-019-7790-1

Sun Q, Chen Y, Ye F, Liu J, Liu D, Ao B et al. Association of hypothyroidism during pregnancy with preconception and early pregnancy exposure to ambient particulate matter. Environ Sci Pollut Res [Internet]. 2023 Jul 12 [cited 2024 Jun 29];30(37):88084–94. https://doi.org/10.1007/s11356-023-28683-7

Wang X, Liu C, Zhang M, Han Y, Aase H, Villanger GD et al. Evaluation of maternal exposure to PM 2.5 and its components on maternal and neonatal thyroid function and birth weight: a cohort study. Thyroid [Internet]. 2019 Aug [cited 2024 Jun 29];29(8):1147–57. https://doi.org/10.1089/thy.2018.0780

Zeng Z, Xu X, Wang Q, Zhang Z, Meng P, Huo X. Maternal exposure to atmospheric PM2.5 and fetal brain development: Associations with BAI1 methylation and thyroid hormones. Environ Pollut [Internet]. 2022 Sep [cited 2024 Jun 29];308:119665. https://linkinghub.elsevier.com/retrieve/pii/S026974912200879X

Zhang X, Huels A, Makuch R, Zhou A, Zheng T, Xia W et al. Association of exposure to ambient particulate matter with maternal thyroid function in early pregnancy. Environ Res [Internet]. 2022 Nov [cited 2024 Jun 29];214:113942. https://linkinghub.elsevier.com/retrieve/pii/S0013935122012695

Zhao Y, Cao Z, Li H, Su X, Yang Y, Liu C et al. Air pollution exposure in association with maternal thyroid function during early pregnancy. J Hazard Mater [Internet]. 2019 Apr [cited 2024 Jun 29];367:188–93. https://linkinghub.elsevier.com/retrieve/pii/S0304389418312263

Zhou Y, Zhu Q, Wang P, Li J, Luo R, Zhao W et al. Early pregnancy PM2.5 exposure and its inorganic constituents affect fetal growth by interrupting maternal thyroid function. Environ Pollut [Internet]. 2022 Aug [cited 2024 Jun 29];307:119481. https://linkinghub.elsevier.com/retrieve/pii/S0269749122006959

Kassotis CD, Iwanowicz LR, Akob DM, Cozzarelli IM, Mumford AC, Orem WH et al. Endocrine disrupting activities of surface water associated with a West Virginia oil and gas industry wastewater disposal site. Sci Total Environ [Internet]. 2016 Jul [cited 2024 Jun 29];557–558:901–10. https://linkinghub.elsevier.com/retrieve/pii/S0048969716305356

Liu Y, Chen H, Zhang L, Zhang T, Ren X. The association between thyroid injury and apoptosis, and alterations of Bax, Bcl-2, and Caspase-3 mRNA/Protein expression induced by nickel sulfate in wistar rats. Biol Trace Elem Res [Internet]. 2020 May [cited 2024 Jun 29];195(1):159–68. https://doi.org/10.1007/s12011-019-01825-0

Rezaei M, Javadmoosavi SY, Mansouri B, Azadi NA, Mehrpour O, Nakhaee S. Thyroid dysfunction: how concentration of toxic and essential elements contribute to risk of hypothyroidism, hyperthyroidism, and thyroid cancer. Environ Sci Pollut Res [Internet]. 2019 Dec [cited 2024 Jun 29];26(35):35787–96. https://doi.org/10.1007/s11356-019-06632-7

Di Ciaula A, Bonfrate L, Noviello M, Portincasa P. Thyroid function: a target for endocrine disruptors, air pollution and radiofrequencies. Endocr Metab Immune Disord Drug Targets [Internet]. 2023 Jul [cited 2024 Aug 20];23(8):1032–40. https://www.eurekaselect.com/196304/article

Derakhshan A, Shu H, Peeters RP, Kortenkamp A, Lindh CH, Demeneix B et al. Association of urinary bisphenols and triclosan with thyroid function during early pregnancy. Environ Int [Internet]. 2019 Dec [cited 2024 Jun 29];133:105123. https://linkinghub.elsevier.com/retrieve/pii/S0160412019319361

Burggren WW, Mueller CA. Developmental critical windows and sensitive periods as three-dimensional constructs in time and space. Physiol Biochem Zool [Internet]. 2015 Mar [cited 2024 Jun 28];88(2):91–102. https://doi.org/10.1086/679906

Delitala AP, Capobianco G, Cherchi PL, Dessole S, Delitala G. Thyroid function and thyroid disorders during pregnancy: a review and care pathway. Arch Gynecol Obstet [Internet]. 2019 Feb [cited 2024 Jun 28];299(2):327–38. https://doi.org/10.1007/s00404-018-5018-8

McNeil AR, Stanford PE. Reporting thyroid function tests in pregnancy. Clin Biochem Rev. 2015;36(4):109–26.

Google Scholar  

Download references

Acknowledgements

We would like to thank Dr. Lance Price, Mr. Paul Levett, and Meredith Clemons for their guidance and instruction. Dr. Jordan Kuiper and Dr. Robert Canales are also acknowledged and thanked for their helpful insights.

We thank the George Washington University Milken Institute School of Public Health for supporting this project.

Author information

Authors and affiliations.

Department of Environmental and Occupational Health, The George Washington University, Washington, District of Columbia, USA

Catherine O’Donnell, Erin J. Campbell & Susan C. Anenberg

Resilience Creative, New York, NY, USA

Sabrina McCormick

You can also search for this author in PubMed   Google Scholar

Contributions

C.O. conceived of the study, conducted the analysis, and was responsible for drafting the manuscript. E.J.C. conducted the literature review, evaluated risk of bias and strength and quality of the evidence, and contributed to manuscript writing. S.C.A. and S.M. reviewed the analysis and contributed to the manuscript writing. All authors read and approved the final manuscript.

Corresponding author

Correspondence to Catherine O’Donnell .

Ethics declarations

Ethics approval and consent to participate.

Not applicable.

Consent for publication

Competing interests.

The authors declare no competing interests.

Additional information

Publisher’s note.

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Electronic supplementary material

Below is the link to the electronic supplementary material.

Supplementary Material 1

Rights and permissions.

Open Access This article is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License, which permits any non-commercial use, sharing, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if you modified the licensed material. You do not have permission under this licence to share adapted material derived from this article or parts of it. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by-nc-nd/4.0/ .

Reprints and permissions

About this article

Cite this article.

O’Donnell, C., Campbell, E.J., McCormick, S. et al. Prenatal exposure to air pollution and maternal and fetal thyroid function: a systematic review of the epidemiological evidence. Environ Health 23 , 78 (2024). https://doi.org/10.1186/s12940-024-01116-9

Download citation

Received : 03 July 2024

Accepted : 15 September 2024

Published : 27 September 2024

DOI : https://doi.org/10.1186/s12940-024-01116-9

Share this article

Anyone you share the following link with will be able to read this content:

Sorry, a shareable link is not currently available for this article.

Provided by the Springer Nature SharedIt content-sharing initiative

• Air pollution
• Thyroid function

Environmental Health

ISSN: 1476-069X

• General enquiries: [email protected]