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Your Environment. Your Health.

Childrens Lungs grew Stronger as Pollution Declined in California

Edward Avol, Frank D. Gilliland, Ph.D.; W. James Gauderman, Ph.D.
University of Southern California
NIEHS Grants P01ES011627, P30ES007048, R03ES022719

New research from NIEHS grantees found that as air quality improved in the Los Angeles basin, children’s lung health also improved. Improving lung function during developmental years could lead to greater lung function in adulthood, potentially reducing risks for adverse health outcomes.

The improving air quality in the Los Angeles basin over the last several decades provided an opportunity to study its potential benefits to human health. As part of the Children's Health Study, the researchers annually measured lung function in three cohorts of children who lived in the same five communities over a 4-year age range (11 to 15 years) but during different calendar periods: 1994-1998, 1997-2001, or 2007-2011. More than 2000 children were included in the study.

After adjusting for age, gender, ethnicity, height, respiratory illness, and other variations, the researchers found large improvements in lung development for children studied in 2007-2011, compared to children studied in 1994-1998 or 1997-2001. The lung function gains strongly correlated with lower levels of particulate pollution (PM2.5 and PM10) and nitrogen dioxide in the communities studied. Regional air quality improved dramatically over the course of the study. For example, the 4-year mean PM2.5 level in the community with the highest levels of particulate matter showed a 43 percent reduction from the 1994-1998 cohort to the 2007-2011 cohort. Lung growth over the four years studied was more than 10 percent greater for children breathing the lower levels of nitrogen dioxide in 2007-2011 compared to those breathing higher levels in 1994-1998.

Citation: Gauderman WJ, Urman R, Avol E, Berhane K, McConnell R, Rappaport E, Chang R, Lurmann F, Gilliland F. 2015. Association of improved air quality with lung development in children. N Engl J Med. 372(10):905-13.

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