Air Pollution Might Affect Lung Development in Children, Study Finds
Children who live in areas with heavy air pollution have reduced lung capacity by age 18 and a higher risk for illness and other respiratory problems later in life, according to a study published on Thursday in the New England Journal of Medicine, the AP/San Jose Mercury News reports. In the "longest study to date of pollution's impact on developing lungs," researchers from the Keck School of Medicine at the University of Southern California tracked 1,759 children in 12 Southern California communities from spring 1993 through spring 2001. According to the American Lung Association, the Los Angeles metropolitan area has the highest rate of fine particle pollution in the nation (Johnson, AP/San Jose Mercury News, 9/9).
Researchers tracked the lung capacity of participants and amount of nitrogen dioxide, acid vapor, particulate matter and elemental carbon in the air (Fackelmann, USA Today, 9/9). The study found that the lungs of participants who lived in the most-polluted communities grew by about 100 millimeters less by age 18, when lungs have developed to their full capacity, than those of participants in the least-polluted communities. Lead study author James Gauderman, an associate professor of preventive medicine at Keck, said that the reduced lung growth translates into a 7% lower lung capacity for girls and a 4% lower capacity for boys (AP/San Jose Mercury News 9/9). In addition, the study found that participants who lived in the most-polluted communities were about five times as likely to have less than 80% of the lung function expected for their age as those who lived in the less-polluted communities.
"We found some significant deficits in growth for kids breathing the most polluted air," Gauderman said. Such study participants in most cases had adequate lung capacity to perform most daily activities without problems, but their reduced capacity could cause problems later in life when added to the normal age-related decrease in lung function, according to Arden Pope, an air pollution expert at Brigham Young University. Gauderman said that individuals who have problems with their lung function often take longer to recover from colds or other respiratory infections than those with healthy lungs. In an editorial that accompanied the study, Jonathan Samet, a lung specialist at Johns Hopkins University, wrote that the results likely would apply to all metropolitan areas in the United States with high levels of car exhaust and other air pollutants (USA Today, 9/9). Samet added that the study provided the first major link between exposure to air pollution and the development of children (Pelton, Baltimore Sun, 9/9). An abstract of the study is available online.
NPR's "All Things Considered" on Wednesday reported on the study. The segment includes comments from Gauderman and Pope (Harris, "All Things Considered," NPR, 9/8). The complete segment is available online in RealPlayer. In addition, NPR's "Morning Edition" on Thursday also reported on the study. The segment includes comments from Dr. Peyton Eggleston, a pediatrician at Johns Hopkins, and Dr. Wayne Morgan, a pediatric pulmonologist at the University of Arizona's College of Medicine (Shapiro, "Morning Edition," NPR, 9/9). The complete segment is available online in RealPlayer.
In a second study published on Thursday in NEJM, researchers from the University of Texas Southwestern Medical Center at Dallas and other institutions found that children who live in metropolitan areas experience fewer problems with asthma when their homes are "scrubbed, filtered, vacuumed, exterminated and otherwise protected from allergy triggers," the Dallas Morning News reports. Researchers tracked 937 children in seven metropolitan areas nationwide. About 50% of participants lived in homes with smokers, 62% lived in homes with cockroaches and 45% lived in homes with water leaks or dampness. Researchers tested study participants for allergies with skin tests, and some of their homes were cleaned to address the specific allergens. The study found that asthma symptoms "plummeted" in conjunction with levels of allergens as a result of the interventions, the Morning News reports.
In the first year of the study, participants whose homes were cleaned experienced 21 fewer days of asthma symptoms than those whose homes were not cleaned, and in the second year, the difference was 16 days. Dr. Darryl Zeldin from the National Institute of Environmental Health Sciences said, "The interventions that these folks used are probably going to be adopted by the allergy and immunology community" (Beil, Dallas Morning News, 9/8). An abstract of the study is available online.