Air Pollution's Future Victims: A Global Crisis

Air pollution is a prevalent health crisis around the world, with many cities recording dangerous levels of air pollution. In 2024, most of the cities with the worst air pollution were located in India, Pakistan, or other parts of Asia. Delhi, India, recorded the second-worst air pollution levels in 2024, driven by crop burning in nearby states, stagnant cold air, and weak wind patterns that trap and concentrate smog over the city. In the United States, the worst air pollution can be found in small towns surrounded by farmland and mountains, where Black and Hispanic populations live. For example, Bakersfield, California, has the most unhealthful air in America due to its location surrounded by mountains that trap toxic farming chemicals, dust, and fumes.

Cities in India, Pakistan, and Asia

Several Asian cities are notorious for their poor air quality, with pollution levels that can be severely detrimental to human health. In 2024, IQAir ranked the world's most polluted cities based on PM2.5 levels, which are fine particles that pose significant health risks as they can penetrate deep into the lungs and bloodstream.

India

Delhi, the capital of India, is often associated with poor air quality. In January 2025, a thick haze blanketed the city, causing a spike in the Air Quality Index (AQI) to 'severe' levels. Stagnant winds reduced visibility, and temperatures dropped to 9.6 degrees Celsius. Such weather conditions, combined with pollution, can have severe health consequences for residents.

Pakistan

While Pakistan's Air Quality Index (AQI) levels are generally considered acceptable, they can fluctuate, and certain pollutants may be a concern for sensitive individuals. Unfortunately, I could not find a list of specific cities in Pakistan with the worst air pollution.

Asia

Asian cities feature prominently on the list of the world's most polluted cities in 2024. Here are some of them:

• Hotan, China
• Kashgar, China
• Lahore, Pakistan
• Delhi, India
• Kolkata, India

Hispanic and Black neighbourhoods in the US

Despite progress toward cleaner air in the US, a study by George Washington University suggests that Hispanic and Black neighbourhoods across the nation are shouldering a growing burden of diseases linked to air pollution. The study, published in the journal Environmental Health Perspectives, found that racial and ethnic disparities in cases of pollutant-linked diseases like asthma increased during the last decade.

Hispanic and Black communities in the US have been found to suffer from higher levels of air pollution, particularly particle pollution. A 2011 analysis revealed that non-Hispanic Blacks and Hispanics were more likely to live in counties with worse particle pollution problems. Non-Hispanic Blacks were also more likely to live in counties with worse ozone pollution. Furthermore, a 2012 study found that unemployed people, those with low incomes or low education, and non-Hispanic Blacks were more likely to live in areas with higher exposures to particle pollution.

The reasons for these disparities are complex and multifaceted. One factor is the legacy of redlining and systemic racism, which has resulted in predominantly non-white areas being located near factories, congested roadways, or shipping routes with heavily polluted air. This is particularly evident in neighbourhoods like Bakersfield, California, where Black and low-income communities are exposed to air pollution from oil wells, freeways, agricultural fields, and rail yards.

The health impacts of air pollution in these communities are significant. Studies have shown that people living in neighbourhoods with high air pollution levels experience a higher risk of premature death, heart disease, lung cancer, stroke, and respiratory issues such as asthma. The disparities in health outcomes have widened over the last decade, even as overall pollution levels have decreased.

Advocates like Emprezz Nontzikelelo from Bakersfield have joined environmental justice movements to address these disparities. They are working to create more green spaces, raise awareness about pollution injustice, and find ways to improve air quality in their communities. Despite the efforts of activists and researchers, the Environmental Protection Agency's air quality standards have been criticised for not adequately protecting marginalised communities from the adverse health effects of air pollution.

Industrial emissions, vehicle exhaust, and fossil fuels

Vehicle exhaust is another significant source of air pollution. Cars, trucks, and buses powered by fossil fuels emit nitrogen oxides, contributing to more than half of the nitrogen oxides in the air. These vehicles also release harmful pollutants like carbon monoxide, a colourless and odourless gas that can cause serious health issues, including difficulty breathing, exhaustion, dizziness, and even death at high levels. Furthermore, studies have linked vehicle exhaust pollutants to adverse impacts on nearly every organ system in the body. Ultrafine particles emitted from vehicles can have serious health consequences, including cardiovascular effects and premature mortality.

Transportation is a major contributor to greenhouse gas emissions, with tailpipe emissions from cars, trucks, and buses accounting for a significant portion of global warming pollution. The production and use of fossil fuels for transportation also contribute to upstream emissions, including extracting, refining, and distributing the fuel. Electric vehicles have zero tailpipe emissions, but it is important to consider their life cycle emissions, including electricity production at power plants.

To address air pollution from industrial emissions and vehicle exhaust, several strategies are being implemented. The deployment of zero-emission trucks and buses, such as electric fleets in cities like New York and Los Angeles, is a positive step towards reducing pollution. The Renewable Fuel Standard program aims to reduce reliance on fossil fuels by promoting renewable fuels produced from plants, crops, and biomass. Additionally, the EPA's SmartWay program helps improve supply chain efficiency and reduce greenhouse gas emissions in the freight transportation sector.

While these initiatives are making progress, it is important to prioritize marginalized communities that are disproportionately affected by air pollution. Ensuring access to cleaner transportation options and prioritizing electric vehicle deployment in these areas is crucial to improving air quality and health outcomes for all.

Outdoor air pollution

The worst-affected regions in terms of outdoor air pollution are Asia, Africa, and South America. In 2024, most of the cities with the worst air pollution were located in India, Pakistan, and other parts of Asia. Dhaka, the capital of Bangladesh, topped the list of the world's most polluted cities in 2023, with a PM2.5 level of 114.5 µg/m3. Other countries that featured on the list in the 2023 update include Iraq, Tajikistan, Nepal, and the UAE.

Africa and South America have fewer public air quality monitoring stations, making it difficult to accurately determine the pollution levels in these regions. However, it is worth noting that N'Djamena, Chad, was the only non-Asian city to rank among the top 20 most polluted cities in 2024.

In the United States, nearly half of the population breathes air that has earned an F rating in the "State of the Air" report for 2025. More than 156 million people live in counties that received an F for either ozone or particle pollution, and over 42 million people reside in counties that received an F for all three air pollution measures.

The area around Bakersfield, California, has been identified as having the most unhealthful air in the country. Surrounded by mountains, Bakersfield is susceptible to the accumulation of toxic farming chemicals, dust, truck and train fumes, and oil-drilling exhaust. Local air regulators' lax enforcement against industrial polluters has been criticized for exacerbating the situation.

Race appears to be a significant factor in the exposure to air pollution in the United States, with predominantly Black and Hispanic neighborhoods bearing the brunt of the worst pollution. This pattern has been observed in cities like Birmingham, Alabama, and Maywood, California.

Health risks of air pollution

Air pollution is a serious global issue, with many cities around the world experiencing poor air quality. Delhi, India, for instance, recorded the second-worst air pollution levels in 2024. The air pollution in Delhi is driven by crop burning in nearby states, stagnant cold air, and weak wind patterns that trap smog over the city. Several Asian countries, including India and Pakistan, tend to have the worst air pollution.

The health risks associated with air pollution are significant and wide-ranging. Here are some of the key health risks associated with air pollution:

Particle Pollution and Respiratory Issues

Particle pollution, also known as particulate matter or soot, is a mixture of tiny solid and liquid particles suspended in the air. This type of pollution is particularly harmful as these particles can be smaller than 1/30th the diameter of a human hair, allowing them to penetrate deep into the lungs and even enter the bloodstream. This can lead to respiratory issues such as asthma, chronic obstructive pulmonary disease (COPD), and bronchitis. Particle pollution is also linked to increased risks of heart attacks, strokes, and premature death.

Cancer Risks

Air pollution has been classified as a human carcinogen by the International Agency for Research on Cancer of the World Health Organization (WHO). Studies have found links between air pollution and increased risks of various cancers, including lung cancer, breast cancer, leukemia, and lymphoma. Fine particulate matter, such as PM2.5, has been associated with an increased overall risk of death.

Adverse Pregnancy Outcomes

Exposure to air pollution during pregnancy can lead to dangerous changes in blood pressure, known as hypertensive disorders, which are a leading cause of pre-term birth, low birth weight, and maternal and fetal health complications. Air pollution is also associated with an increased risk of asthma in children, which is more prevalent in low-income urban areas.

Cardiac Problems

Air pollution has been linked to cardiac issues, including reduced lung function and increased emergency department visits and hospital admissions for heart-related problems. Fine particulate matter can impair blood vessel function and accelerate calcification in arteries, contributing to heart disease.

Neurological and Cognitive Impacts

There is growing evidence that air pollution may affect neurological development and cognitive function, particularly in children. Exposure to air pollution has been linked to an increased risk of neurological diseases, cognitive impairment, and emotional problems in adolescence.

Diabetes

Air pollution has also been associated with an increased risk of diabetes, particularly in vulnerable populations.

Overall, the health risks of air pollution are extensive and impact people of all ages, from children to older adults. Certain groups, such as people of colour, individuals with low incomes, and those with pre-existing health conditions, are more susceptible to the harmful effects of air pollution.

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