USC/UCLA Children's Center Finds that Children Living Near Busy Roads More Likely to Develop Asthma Symptoms
(New York Times, Tuesday, May 9, 2006)
By Eric Nagourney/New York Times
Published: May 9, 2006
Children living near busy roads are likely to be at increased risk for developing asthma symptoms, according to results from the USC/UCLA Children's Center. The study, utilizing data from nearly 5,000 children, found that residence within 75 meters of a major road (equivalent to about 250 feet, or the length of a city block) led to a 50-percent elevated risk of reporting asthma symptoms and using medications for asthma within the past year. Among children with no parental history of asthma, those who had resided at an address close to heavy traffic since before age 2 experienced even higher risks (2.5-fold for asthma and 2.7-fold for wheezing), suggesting that a cumulative lifetime exposure to traffic pollutants may raise health risks. The effect was also larger in girls.
The asthma risk decreased to background levels by 200 meters (about 650 feet, or about 2 ½ blocks) from the roadway. However, the study, published in Environmental Health Perspectives, did not show an increased risk of asthma for children moving to the residence after 2 years of age, or for children with a parental history of asthma. This suggests that exposure to air pollutants while their mothers were pregnant or in infancy may have increased their susceptibility.
The children, aged 5 to 7 years, lived in 13 Southern California communities. The researchers used information from the California Department of Transportation about roadway type and traffic volume to model vehicle exhaust at each child's home, and a similar pattern of effects was observed with traffic-modeled exposure.
The researchers suggest that locating playgrounds, parks, and sports fields away from major roadways could prevent children from inhaling the most concentrated traffic fumes, with the potential to decrease the incidence of asthma symptoms. The reason for larger effects in those with no parental history of asthma is so far unexplained and they suggest this merits further investigation.
McConnell R, Berhane K, Yao L, Jerrett M, Lurmann F, Gilliland F, Kunzli N, Gauderman J, Avol E, Thomas D, Peters J 2006. Traffic, susceptibility, and childhood asthma. Environmental Health Perspectives . May 2006; 114(5):766-72.
New York Times: “At Risk: High-Traffic Areas Tied to Children’s Asthma Risk.”