Population-Based Study of Traffic-Related Air Pollution and Obesity in Mexican Americans

Objective The purpose of this study was to assess the cross-sectional association between residential exposure to traffic-related air pollution and obesity in Mexican American adults. Methods A total of 7,826 self-reported Mexican Americans aged 20 to 60 years old were selected from the baseline survey of the MD Anderson Mano-a-Mano Mexican American Cohort. Concentrations of traffic-related particulate matter with aerodynamic diameter < 2.5 mu m were modeled at geocoded residential addresses using a dispersion models. The residential proximity to the nearest major road was calculated using a Geographic Information System. Linear and logistic regression models were used to estimate the adjusted associations between exposure and obesity, defined as BMI >= 30. Results More than half (53.6%) of the study participants had BMI >= 30, with a higher prevalence in women (55.0%) than in men (48.8%). Overall higher traffic-related air pollution exposures were associated with lower BMI in men but higher BMI in women. By stratifying for those who lived in a 0- to 1,500-m road buffer, the one-interquartile-range (685.1 m) increase of distance to a major road had a significant association with a 0.58-kg/m(2) lower BMI (95% CI: -0.92 to -0.24) in women. Conclusions Exposure to intensive traffic is associated with increased risk of obesity in Mexican American women.