Distance-Weighted Traffic Density in Proximity to a Home is a Risk Factor for Leukemia and Other Childhood Cancers

摘要

Occupational exposure to elevated concentrations of ben- zene is a known cause of leukemia in adults. Concentra- tions of benzene from motor vehicle exhaust could be elevated along highly trafficked streets. Several studies have reported significant associations between proximity to highly trafficked streets and the occurrence of childhood cancers and childhood leukemia. These associations may be due to chronic exposure to benzene or other carcinogenic compo- nents of vehicle exhaust from these nearby streets or to some other factor (e.g., noise, increased light exposure, or some unaccounted-for socioeconomic variable). We used data for homes studied in an earlier childhood cancer study con- ducted in Denver, CO, in the 1980s. No air pollution mea- surements were made in the original study. We identified the highest trafficked street near each study home and ob- tained the traffic density in 1979 and 1990. Traffic density was weighted for the distance from the street to the home using 3 different widths of Gaussian curves to approximate the decay of the emissions into the surrounding neighbor- hoods.