Maternal residential atrazine exposure and risk for choanal atresia and stenosis in offspring.

OBJECTIVE To assess the relationship between estimated residential maternal exposure to atrazine during pregnancy and the risk for choanal atresia or stenosis in offspring. STUDY DESIGN Data for 280 nonsyndromic cases and randomly selected, population-based controls delivered between 1999 and 2008 were obtained from the Texas Birth Defects Registry. County-level estimates of atrazine levels obtained from the US Geological Survey were assigned to cases and controls based on maternal county of residence at delivery. Unconditional logistic regression was used to assess the relationship between maternal residential atrazine exposure and the risk for choanal atresia or stenosis in offspring. RESULTS Compared with offspring of mothers with low levels of estimated residential atrazine exposure, those with high levels had nearly a 2-fold increase in risk for choanal atresia or stenosis (aOR, 1.79; 95% CI, 1.17-2.74). A significant linear trend was also observed with increasing levels of atrazine exposure (adjusted P = .002). CONCLUSION A link between maternal exposure to endocrine disruptors, such as atrazine, and the risk of choanal atresia is plausible based on previous findings. Our results lend further support to this hypothesis.