Breathing Polluted Air: A Slow, Silent Killer?

Air pollution is a pressing issue that poses a significant threat to human health and the environment. It is caused by various factors, including the combustion of fossil fuels, vehicle emissions, industrial activities, and natural events. The impact of breathing polluted air can be detrimental, leading to an increased risk of respiratory infections, heart disease, stroke, and lung cancer. Certain groups, such as people with asthma or chronic obstructive pulmonary disease (COPD), children, and individuals from low-income communities, are more vulnerable to the adverse effects of air pollution. As awareness of this invisible threat grows, efforts to mitigate air pollution and improve air quality become increasingly crucial to safeguard public health and the planet.

The impact of air pollution on health

Breathing polluted air has a wide range of negative impacts on human health. According to the World Health Organization (WHO), 99% of the global population breathes air that exceeds the recommended guideline limits and contains high levels of pollutants. This has led to serious health issues and even premature deaths, especially in low- and middle-income countries (LMICs).

One of the most vulnerable groups affected by air pollution are children. Evidence suggests that exposure to air pollution can harm children before they are born, with potential effects on birth weight due to their mothers' exposure. Air pollution is also linked to lower respiratory infections, which are the second leading cause of death for children under five years old. Additionally, air pollution can slow lung development in children, impacting their health in the present and reducing their lung function as adults.

The elderly are another vulnerable group. Older adults, especially those with existing respiratory conditions such as chronic obstructive pulmonary disease (COPD), can experience worsened symptoms and increased difficulty in breathing due to indoor and outdoor air pollution. High levels of indoor air pollution, such as nitrogen dioxide produced by cooking, can significantly impact the respiratory health of the elderly.

Air pollution also exacerbates respiratory conditions and triggers cardiovascular problems in people of all ages. It increases the risk of asthma attacks, shortness of breath, coughing, wheezing, and chest pain. Additionally, it contributes to more severe health issues such as heart attacks, strokes, and lung cancer.

Furthermore, air pollution has been linked to developmental damage, with potential impacts on neurodevelopment and metabolic diseases in children. The impact of air pollution on mental health is also an emerging area of research, suggesting that air pollution may have even broader implications for human health than previously understood.

The sources of air pollution vary and include indoor and outdoor sources. Indoor air pollution is mainly caused by the use of solid fuels, such as wood, charcoal, and coal, for cooking and heating, particularly in low-income households. Outdoor air pollution is predominantly caused by the combustion of fossil fuels, with vehicles, power plants, and industrial sources being significant contributors.

The effects of air pollution on children

Breathing polluted air has disastrous effects on children. According to the World Health Organization (WHO), almost the entire global population (99%) breathes air that exceeds WHO guideline limits and contains high levels of pollutants. This has led to over 5 million deaths of children under the age of 5, with more than 27% of those deaths (1.7 million) attributable to environmental factors, primarily air pollution.

Children are more vulnerable to the adverse health effects of air pollution due to their immature immune systems, higher minute ventilation, involvement in vigorous activities, and the longer periods of time they spend outdoors. Their lungs are still developing, and air pollution can stunt this development, harming their health in the present and in the future as adults. A large number of studies have reported an association between exposure to air pollutants and several morbidity and mortality outcomes in children.

The State of Global Air 2024 report highlights how air pollution was the second leading risk factor for death among children under 5 years in 2021, after malnutrition. The report presents information on exposures to and health impacts of exposure to common air pollutants, including fine particulate matter, ozone, and nitrogen dioxide. Exposure to air pollution can slow and stunt lung development in growing children, harming their health now and reducing their lung function as adults. It also increases the risk of lung infections, especially in children.

In addition to the immediate health impacts, there is emerging evidence linking air pollution exposure to cancer, neurodevelopmental and metabolic diseases in children. Evidence also suggests that air pollution could harm children before they are born, through their mothers' exposure, leading to reduced birth weight, premature birth, intrauterine growth retardation, and abnormal birth length.

To protect children from the harmful effects of air pollution, it is crucial to reduce their exposure and improve air quality. This can be achieved through local, state, and national policy changes, as well as through the design of school and childcare facilities, the use of green infrastructure, and the reduction of toxic chemicals and mould in indoor spaces.

Air pollution and climate change

Breathing polluted air has a range of negative health impacts. These include asthma attacks, coughing, wheezing, shortness of breath, and chest pain. More seriously, air pollution can cause lung cancer, heart attacks, and stroke. It can also increase the risk of lung infections, especially in children, and worsen symptoms for those with chronic obstructive pulmonary disease (COPD). Emerging evidence also links air pollution exposure to cancer, neurodevelopmental and metabolic diseases in children.

The World Health Organization (WHO) has found that almost the entire global population (99%) breathes air that exceeds its guideline limits and contains high levels of pollutants. Low- and middle-income countries suffer the highest exposures, with 3.68 million premature deaths each year attributable to air pollution—almost eight times the mortality rates in high-income countries.

Air pollution is also a significant contributor to climate change. Burning fossil fuels, for example, releases greenhouse gases that accelerate global warming. Black carbon, a component of fine particulate matter, is one of the largest contributors to global warming after carbon dioxide (CO2). It warms the Earth's atmosphere by absorbing sunlight, accelerating the melting of snow and ice. Regulatory initiatives, partnership programs, and individual actions can all help reduce air pollutants and the greenhouse gases that contribute to climate change.

Transitioning to clean energy sources like wind and solar power, and increasing the use of electric vehicles, can help reduce air pollution and mitigate climate change. In Illinois, for example, transitioning to clean energy sources is estimated to prevent nearly 2,000 lung-related health issues each year. Electric vehicles can eliminate the air pollution emitted by conventional and hybrid gasoline and diesel vehicles.

Household air pollution

Breathing polluted air is extremely harmful to human health and well-being. According to the World Health Organization (WHO), 99% of the global population breathes air that exceeds the recommended limits and contains high levels of pollutants. This has disastrous effects, particularly on children. More than 27% of the over 5 million deaths of children under the age of five worldwide can be attributed to environmental factors, with air pollution being the most significant.

The health risks associated with household air pollution are significant. Exposure to household air pollution causes short-term health effects such as burning eyes, coughing, and nose and throat irritation. It also increases the risk of musculoskeletal damage from carrying heavy loads of fuel. Additionally, the use of open fires and unstable stoves poses safety risks, especially to children, who are more susceptible to burns and scalds.

The impact of household air pollution on long-term health is even more concerning. It is a leading cause of premature deaths, with over 3 million people dying prematurely each year from diseases caused by household air pollution. The leading causes of these deaths include ischaemic heart disease, lower respiratory infections, stroke, chronic obstructive pulmonary disease (COPD), and lung cancer. Exposure to household air pollution is also linked to developmental damage in children, slowing and stunting their lung development and increasing their risk of infections.

To address household air pollution, it is essential to transition to clean fuels and technologies. This includes the use of solar, electricity, biogas, liquefied petroleum gas (LPG), natural gas, alcohol fuels, and biomass stoves that meet emission targets. By expanding access to and adoption of these cleaner alternatives, we can significantly reduce the health risks associated with household air pollution and improve the well-being of those affected.

Air pollution and income levels

Air pollution is one of the leading causes of health complications and mortality worldwide, with certain income groups bearing the brunt of the adverse effects. Studies have shown that low-income communities are exposed to higher levels of air pollution and are more vulnerable to its impacts. This disparity is evident in both developing and developed nations, with the issue persisting even in wealthy countries like the United States.

In the US, racial and ethnic minorities, as well as low-income populations, face higher levels of dangerous fine particulate air pollution (PM2.5). A study by the Harvard T.H. Chan School of Public Health found that Blacks, Asians, Hispanics, Latinos, and low-income groups are exposed to higher levels of PM2.5 pollution. This disparity has increased over time, with areas of the US with lower-income groups experiencing higher average PM2.5 levels than higher-income areas.

Low-income communities in the US continue to bear the brunt of pollution exposure, despite the improvements in air quality since the passing of the Clean Air Act in 1963. Long-standing violations of air quality standards by large corporations often occur in low-income areas, subjecting these communities to unsafe levels of pollutants. Additionally, low-income groups are more likely to reside in areas with higher traffic exposure, dirtier workplaces, and limited access to healthcare, further exacerbating the impact of air pollution on their health.

The situation is even more dire in low- and middle-income countries, where 80% of the world's population resides. In these countries, air pollution levels are particularly high due to the reliance on polluting industries and technologies, less stringent air quality regulations, and the prevalence of older, more polluting machinery and vehicles. As a result, people living in these countries are more vulnerable to the health effects of air pollution, with higher rates of respiratory and cardiovascular diseases.

Furthermore, within low- and middle-income countries, certain populations are even more vulnerable to the adverse impacts of air pollution. These include populations living in slums or near busy highways, lacking access to clean cooking fuels, or working in certain occupations. Women and children in these households are disproportionately affected as they spend more time in polluted living spaces and bear the burden of household energy provision, limiting their opportunities for economic development.

Overall, the evidence suggests a strong correlation between income levels and the impact of air pollution, with lower-income groups facing higher exposure and increased vulnerability to its health effects. Addressing these disparities requires targeted air pollution reduction strategies that aim to protect all people equally from environmental hazards.

Frequently asked questions