Air Pollution In The Us: What's The Deal?

Despite improvements in air quality over the past decades, air pollution remains a pressing issue in the United States, with approximately 140 to 156 million people exposed to unhealthy levels of soot, ozone, or particle pollution. This problem is exacerbated by the changing climate and the Trump administration's push to relax air quality regulations, threatening the progress made by the Clean Air Act and the Environmental Protection Agency (EPA). The main sources of environmental pollution are the burning of fossil fuels, dust generated by traffic, biomass use, oil fracking, and coal mining. These factors contribute to the high number of human deaths, estimated between 100,000 to 200,000, attributed to air pollution in the US.

The Clean Air Act and its impact

The Clean Air Act is a comprehensive federal law that gives the Environmental Protection Agency (EPA) the authority to regulate air pollutants and polluting industries. The Act was first implemented in 1963 and then updated significantly in 1970, with further amendments in 1977, 1990, 2022, and 2024.

The Clean Air Act has been instrumental in reducing air pollution and improving air quality in the United States. It has helped keep the air clean, combat climate change, and protect public health. The Act focuses on lowering levels of several pollutants known to harm human health, including particulate matter, ozone, sulfur dioxide, nitrogen dioxide, carbon monoxide, and lead.

Since the implementation of the Clean Air Act, studies have found profound health improvements linked to better air quality. The law has reduced healthcare costs and absences from work or school. It has also benefited low-income communities and communities of color, where polluting facilities are often located. The Act has been particularly successful in reducing emissions from transportation, power plants, and manufacturing over time.

Despite the successes of the Clean Air Act, air pollution remains a problem for many Americans. In 2025, it was reported that 46% of Americans (approximately 156 million people) were living in places with unhealthy levels of ozone or particle pollution. This is nearly 25 million more people breathing unhealthy air compared to the previous year's report. The report also found that extreme heat, drought, and wildfires are contributing to worsening air quality across the United States.

The Clean Air Act continues to face challenges, including environmental justice issues. African American populations are disproportionately affected by poor air quality, as they often inhabit areas with the highest pollution levels. Additionally, the EPA, which is responsible for monitoring and enforcing air pollution regulations, has faced staffing and funding cuts that endanger its work.

The role of the EPA

The United States Environmental Protection Agency (EPA) is a federal agency that plays a crucial role in regulating air pollution and protecting human health and the environment. The EPA was established on December 2, 1970, in response to widespread public environmental concerns that gained traction in the 1950s and 1960s.

One of the key roles of the EPA is to monitor and reduce dangerous air pollutants through various comprehensive programs and regulations. The EPA develops National Ambient Air Quality Standards (NAAQS) for key pollutants such as ozone, particulate matter, carbon monoxide, sulfur dioxide, nitrogen dioxide, and lead. These standards are based on the latest scientific research to ensure adequate protection for public health and the environment. The EPA also enforces the Clean Air Act, which was first implemented in 1963 and then significantly updated in 1970 and subsequent years. The Clean Air Act focuses on lowering levels of several pollutants known to harm human health, and the EPA is responsible for revisiting the science every five years to adjust the regulations accordingly.

The EPA has achieved significant reductions in air pollution over the years, preventing hundreds of thousands of serious health impacts annually. From 1990 to 2017, emissions of air toxics declined by 74%, and total emissions of the six principal air pollutants dropped by 78% between 1970 and 2023. The EPA has also developed national programs to further reduce air emissions and improve air quality, benefiting the health, longevity, and quality of life for all Americans.

Despite these successes, air pollution remains a significant issue in the United States, with nearly half of Americans still breathing unhealthy air. The EPA faces challenges such as staffing and funding cuts, and there have been concerns about relaxing air quality regulations, which could undermine the progress made in improving air quality. However, the EPA continues to play a vital role in protecting public health and the environment, and its work is essential in addressing the complex issue of air pollution in the United States.

Coal mining and burning

Coal-fired power plants are a significant source of fine particulate matter (PM2.5) air pollution, which includes soot, fly ash, and bottom ash. These particles can cause chronic bronchitis, aggravate asthma, lead to cardiovascular issues, and even result in premature death. In 2014, US coal power plants emitted a substantial amount of airborne particles, including 197,286 tons of small airborne particles (10 micrometers or less in diameter).

The combustion of coal releases carbon dioxide (CO2), which is the primary greenhouse gas produced from burning fossil fuels. CO2 emissions from burning coal for energy accounted for about 19% of total US energy-related CO2 emissions in 2022. Additionally, coal mining and burning release other harmful substances, such as sulfur dioxide, nitrogen oxides, and mercury, which contribute to acid rain, smog, and respiratory problems.

The environmental impacts of coal mining extend beyond air pollution. Surface mining, a common practice in the US, involves removing layers of soil and rock to expose underground coal deposits. This process often requires clearing forests and stripping away the earth, leaving behind degraded landscapes that cannot support wildlife. Mountaintop removal mining, as seen in the Appalachian Mountains, uses explosives to remove mountain tops, altering the landscape and burying essential tributaries. This type of mining has led to the loss of over 2,000 miles of headwater streams and has severe impacts on water quality.

Acid mine drainage (AMD) is another significant issue in coal mining areas. AMD occurs when water reacts with sulfur-bearing minerals in rocks, resulting in highly acidic water containing toxic heavy metals. This polluted water poses threats to aquatic wildlife and nearby communities, rendering waterways unusable for drinking and recreation.

To address these issues, the US government has implemented regulations such as the Clean Air Act and the Clean Water Act, which require industries, including coal, to reduce pollutants released into the air and water. Additionally, research and emerging technologies, such as carbon capture and storage (CCS), are being explored to reduce CO2 emissions from burning coal. However, the transition to renewable energy sources is crucial to mitigating the environmental and health harms caused by coal mining and burning.

Oil fracking

One of the main issues with oil fracking is the release of methane, a potent greenhouse gas that traps 25 times more heat than carbon dioxide. The process of fracking can result in methane leakage, contributing to the greenhouse effect and increasing global warming. Research indicates that the US oil and gas industry emits 16.9 million metric tons of methane annually, with the US accounting for more methane emissions than 164 other countries combined.

In addition to methane, fracking releases other toxic compounds and airborne hydrocarbons, including nitrogen oxides, benzene, hydrogen sulfide, and other hydrocarbons. These pollutants can cause a range of health issues, such as eye, nose, and throat irritation, respiratory illnesses, central nervous system damage, birth defects, cancer, and even premature death. The risk of cancer is particularly elevated within 0.5 miles of a fracking well, according to Mrdjen and Lee (2016).

The heavy construction activity associated with fracking also generates particulate matter and stirs up dust, which reacts with volatile organic compounds to increase ground-level ozone concentrations. This leads to dense smog, which can affect communities located near gas production activity and along gas pipelines. Flaring, a process used to burn off excess gas, also emits air pollutants, including sulfur dioxide, which can cause lung damage, respiratory illness, heart conditions, and premature death.

The expansion of the oil and gas industry through fracking has brought development closer to communities, increasing human exposure to new contaminants and health threats. While efforts have been made to implement regulations and standards to limit air pollution from the oil and gas industry, there are still gaps and insufficient protections in place. As a result, communities across the US are fighting back, with organizations like the Center for Biological Diversity working to ban fracking and protect the environment and public health.

Vehicle emissions

One of the main sources of air pollution from vehicles is the burning of fossil fuels in combustion engines. This includes gasoline and diesel engines in cars, trucks, and other vehicles. The United States Environmental Protection Agency (EPA) has taken steps to reduce these emissions by establishing fuel economy standards and setting corporate average fuel economy levels. Despite these efforts, the number of vehicle miles traveled has increased by 194% between 1970 and 2023, contributing to the overall air pollution problem.

In addition to the direct emissions from combustion engines, traffic on road surfaces also generates dust and other particulate matter that contributes to air pollution. This is especially prevalent in urban areas with busy roads and high traffic volume. The EPA has also addressed these mobile sources of air pollution by developing stringent emission standards for on-road and non-road diesel and gasoline engines, significantly reducing emissions of mobile source air toxics.

Furthermore, the EPA has proposed rules and programs to reduce emissions from the oil and gas industry, such as the National Gas STAR Methane Challenge Program, which encourages oil and gas companies to reduce methane emissions. While these initiatives have helped, the overall impact of vehicle emissions on air quality remains significant.

To address this issue, states have adopted policies such as vehicle inspection regimes, electric vehicle subsidies, and the provision of public transportation to reduce the number of vehicles on the road. These policies aim to decrease vehicle emissions directly and provide alternative transportation options to help improve air quality. Despite these efforts, air pollution from vehicles continues to impact the health of millions of Americans, with studies showing that air pollution shortens life expectancy and increases asthma rates.

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