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Your Environment. Your Health.

Air Pollution

Air pollution affects people’s health in a variety of ways. These health effects can be seen in the young and old as well as the healthy and infirm. NIEHS is working to understand how air pollution is associated with certain diseases and how to prevent or lessen harm from exposures. With both outdoor and indoor sources, air pollution is a health issue with global consequences.

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.

NIEHS-funded researchers are studying the biological mechanisms that cause and worsen diseases linked to air pollution exposure. They are examining the role that air pollution plays in the development of various diseases, the biological effects of air pollution on the body, and are identifying groups who are most susceptible. Researchers are also studying 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 is funding research on pollutants that include particulate matter, ultrafine particles, ozone, carbon monoxide, nitrogen dioxide, and ozone.

NIEHS research has contributed a sound scientific base for the development of more stringent air quality standards by regulatory agencies while also contributing to the identification of new risks. As research in this area advances, it will continue to inform public health interventions, including regulatory actions, to improve health and protect quality of life.

Indoor Air

Gas stoves and heating units can contribute indoor pollutants such as nitrogen oxide, and indoor mold, tobacco smoke, pet dander, and pest allergens can cause or exacerbate health problems. Many air pollutants created outside can penetrate the indoors and accumulate, especially if buildings have poor ventilation.

NIEHS funds research about the health effects of indoor air pollutants found in homes as well as the workplace, which can include pesticides, ultrafine particles, nanoparticles, and fumes from industrial chemicals.

To better understand how people are affected by air pollution, especially as people move between indoor and outdoor environments, researchers are developing technologies to measure personal exposures and collect data on when and where exposures occurred. They are also considering factors such as a person’s activity levels, which might increase inhalation of pollutants and bring about deeper deposition in the lungs. This work contributes to the NIEHS efforts to measure all the exposures a person experiences during a lifetime, a concept known as Exposure Biology and the Exposome.

Global concerns

While all air pollution problems have a global nature, NIEHS also focuses on health problems associated with traditional cookstoves that burn solid fuels, such as wood, crop waste, or dung, and open fires. The smoke from these cooking methods can contain high levels of health-damaging pollutants such as fine particles and carbon monoxide. The 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 heat waves and droughts that come with climate change, which can greatly alter air quality in places around the world. NIEHS-funded scientists are studying how climate change influences health effects from air pollution.

For additional information on what NIEHS grantees are doing, visit our Who We Fund tool.