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Air Pollution & Respiratory Disease

Research conducted by NIEHS scientists has shown that long-term exposure to air pollutants increases the risk of respiratory illnesses such as allergies, asthma, chronic obstructive pulmonary disease, and lung cancer. Children and the elderly are particularly vulnerable to the health effects of ozone, fine particles, and other airborne toxicants. This research has resulted in the development of more stringent air quality standards that promote a higher quality of life, protect the health of children, the elderly and other vulnerable populations, and reduce the costs associated with respiratory disease.

One of the first studies to establish a link between air pollution and respiratory health was the NIEHS-funded Six Cities Study, a long-term study on residents of six U.S. cities to assess the effects of common air pollutants on the risk of pulmonary and cardiovascular disease. The study results showed that people living in the more polluted cities had a higher risk of hospitalization and early death from lung cancer and other respiratory diseases than those living in the less polluted cities.

Recent data collected by NIEHS-funded scientists at the University of Southern California suggest that exposure to pollutants in vehicle and fossil fuel emissions may hinder lung development and limit breathing capacity for a lifetime. Their research shows that children who live in highly polluted communities are five times more likely to have clinically low lung function—less than 80% of the lung function normal for their age.

Other studies conducted by the University of Southern California researchers indicate that increases in ground-level ozone, a highly reactive form of oxygen that is the primary component of urban smog, may actually cause asthma. Children who were active in outdoor sports in areas with high ozone concentrations were more than three times as likely to develop asthma as those who did not engage in outdoor sports during the five-year study.

Air Pollution & Respiratory Disease: Estimated Reductions in Respiratory Illness Due to Enactment of Clear Skies ActLives saved by research on the health consequences of environmental pollutants can be counted in the millions. According to the Environmental Protection Agency’s estimates on air pollution, the commitment to new air quality standards and cleaner air will prevent 23,000 premature American deaths, 1.7 million cases of asthma attack or aggravation of chronic asthma, 67,000 new cases of acute and chronic bronchitis, 22,000 respiratory-related hospital admissions, and 42,000 hospital admissions for cardiovascular disease by the year 2010.

Other benefits of cleaner air, according to a study by NIEHS-funded researchers at the University of Washington, include 200 fewer cases of post neonatal mortality, 10,000 fewer infants of low birth weight, and 40,000 fewer emergency room visits for children by 2010. These findings demonstrate the impact that NIEHS-supported research and subsequent regulatory actions have had on protecting the health of our nation’s children and other vulnerable populations.

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Last Reviewed: November 09, 2007