In Utero Organochlorine Exposure and Obesity in Children of Farmworkers

Abstract

ISEE-0465 Background and Objective: In utero exposure to endocrine disrupting compounds, such as DDT and DDE, has been hypothesized to increase risk of obesity later in life. The Center for the Health Assessment of Mothers and Children of Salinas (CHAMACOS) study is a longitudinal birth cohort study of low-income Latinas living in an agricultural community in California. We examined the relation of in utero DDT and DDE exposure with obesity at 5 and 7 years. Methods: We include 265 CHAMACOS children who had maternal serum DDT levels and follow-up at 5 and 7 years. In utero exposure to DDT and DDE was measured in maternal serum during pregnancy and reported as lipid-adjusted values (ng/g). At 5- and 7-years, standing height (cm) and weight (g) were measured. Body mass index (BMI) was calculated as weight (kg) / height (m)2. Obesity was defined as ≥95th percentile of the sex-specific BMI-for-age calculated using 2000 Centers for Disease Control and Prevention growth charts. Results: At 5 years, 87 (33%) of 265 children were obese. The prevalence of obesity increased with exposure to DDT (I: 1.5–7.3 ng/g (29.9%); II: 7.4–11.6 ng/g (33.3%); III: 11.7–41.6 ng/g (34.8%); IV: 41.7–33,174.0 ng/g (33.3%)) and DDE (I: 48.7–597.4 ng/g (26.9%); II: 597.5–1,067.6 ng/g (36.4%); III: 1,067.7–2,679.7 ng/g (28.8%); IV: 2,679.8–159,303.3 ng/g (39.4%)). Compared with children in the lowest quartile of exposure, the odds of obesity was increased in the highest quartile of exposure for DDE (IV: OR = 1.77, 95% CI 0.85, 3.68, P = 0.13), but not for DDT (IV: OR = 1.18, 95% CI 0.56, 2.44, P = 0.67). Conclusion: At 5 years, the prevalence of obesity in the CHAMCOS cohort is high. We found some evidence that in utero DDE but not DDT exposure may increase the likelihood of becoming obese with age. We will present the 7 year data.