Prenatal exposure to organochlorine pesticides and birth outcomes in Bolivia

Abstract

The use of pesticide DDT and other organochlorine pesticides has been relatively recently banned in Bolivia and, furthermore, and there are evidences of illegal trade in the country. Our research group has identified highly exposed population subgroups in recent biomonitoring studies performed in Eastern Bolivia. Furthermore, we found evidences of the potential impact of prenatal exposure to DDT and its main metabolite p,p´-DDE on birth anthropometric measures and gestational length in a mother-child cohort recruited in Santa Cruz de la Sierra. Interestingly, the pattern of exposure was somewhat different than most of the previously studied cohorts, with o,p´-DDT detected in 82.5% of samples at median concentration of 0.22, and p,p´-DDE in 86.5% of samples at median concentration of 1.01 ng/mL. Opposite associations with birth weight were found for p,p´-DDE (β=0.012, p=0.006) and o,p´-DDT (β=-0.014, p=0.039), and these associations were stronger when both chemicals were entered in the same model. p,p´-DDE was negatively associated with gestation time (β=-0.004, p=0.012), and o,p´-DDT was borderline negatively associated with newborn head circumference (β=-0.004, p=0.054). We observed no relevant changes in the magnitude of the coefficients or in statistical significance after adjustment for TSH levels. This study indicates a possible impact of prenatal exposure to o,p´-DDT and p,p´-DDE on newborn anthropometric measurements in a population showing evidence of recent exposure to the pesticide DDT.