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Your Environment. Your Health.

Air Pollution

toddler with breathing mask

Air pollution affects an individual’s health in a variety of ways. The effects of air pollution can be seen in the young and old as well as the healthy and sick.

With both outdoor and indoor sources, air pollution is a health issue with global consequences. NIEHS is working to understand how air pollution is associated with certain diseases and how to prevent or reduce harm from exposures.

Air pollution is linked to health problems in the respiratory, cardiovascular, reproductive, neurological, and immune systems. For example, people with asthma can have difficulty breathing if air pollution is high, and prenatal and early childhood air pollution exposure is linked with neurobehavioral problems. Long-term exposure can cause cancer, and, more recently, scientists have discovered associations with obesity and diabetes.

What NIEHS Is Doing

NIEHS-funded researchers study the biological mechanisms that lead to and exacerbate diseases linked to air pollution exposure. They examine how air pollution affects disease development — especially on those in vulnerable groups — and the biological effects of air pollution on the body.

Researchers also study the combined effects of air pollution and other factors in the indoor and outdoor environment.

Outdoor Air

Outdoor air pollutants come from vehicle emissions, factory chimneys, chemical manufacturing, forest fires and other sources. NIEHS funds research on pollutants that include particulate matter, ultrafine particles, ozone, carbon monoxide and nitrogen dioxide.

NIEHS research contributes to the identification of new risks and creates a sound scientific base for the development of stricter air quality standards by regulatory agencies. As research in this area advances, it continues to inform public health interventions, including regulatory actions, to improve health and protect quality of life.

Indoor Air

Gas stoves and heating units can release air pollutants, such as nitrogen dioxide, into the home and other indoor environments. Mold, tobacco smoke, pet dander, and pest allergens can also contribute to poor indoor air quality. Additionally, outdoor air pollutants can penetrate the indoor environment and accumulate, especially if buildings have poor ventilation. Exposure to these indoor pollutants can cause or worsen health problems.

NIEHS funds research on the health effects of indoor air pollutants such as pesticides, ultrafine particles, nanoparticles, and fumes from industrial chemicals found in homes and the workplace.

To better understand the effects of air pollution, especially as individuals move between indoor and outdoor environments, researchers develop technologies to measure and collect data on personal exposures. They also consider factors such as a person’s activity levels, which could increase inhalation of pollutants.

Overall, this work contributes to NIEHS efforts to measure all the exposures of a person experiences during their lifetime, a concept known as the exposome.

Global Concerns

women using a cookstove in India

While all air pollution problems have a global nature, NIEHS also focuses on health problems associated with open fires and traditional cookstoves that burn solid fuels, such as wood, crop waste, or dung. About 3 billion people around the globe – nearly half the world’s population – rely on open fires and traditional stoves for cooking. The smoke from these cooking methods can contain high levels of health-damaging pollutants such as fine particles and carbon monoxide. NIEHS funds research on cookstoves and their health effects in Ghana, Nepal, Peru, and Nicaragua, among other countries. Scientists are also testing interventions involving less-polluting stove designs and proper ventilation.

Another global factor affecting air pollution is the changing global climate, and the heat waves and droughts that come with it. NIEHS-funded scientists study how climate influences health effects from air pollution.

For additional information on the work of NIEHS grantees, visit our Who We Fund tool.

Program Contact

Srikanth Nadadur, Ph.D.
Sri Nadadur, Ph.D.
Health Scientist Administrator

Tel 984-287-3296
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