RESUMO
The present study was conducted to detect placental and breast milk (BM) transfer of organochlorine pesticides (OCPs) between biological compartments in healthy lactating mothers. The study explores the effect of parity, breast-feeding and urban/rural residence on body burden of OCP residues. The study included 38 healthy participants submitted to cesarean delivery. Sociodemographic data and specimens of maternal and umbilical sera, adipose tissue (Adp T) and BM were collected. Specimens were analyzed to detect OCP residues. The lindane in BM, o,p'-dichlorodiphenyldichloroethane (DDD) in maternal serum (MS) and total dichlorodiphenyltrichloroethane (DDT) and o,p'-dichlorodiphenyldichloroethylene in umbilical serum were the only detected residues in significantly higher frequencies and/or means in the primigravidae than multigravidae. There was a high risk of detecting o,p'-DDD (odds ratio = 8.3) in umbilical serum of the mothers with o,p'-DDD detected in the MS. Total DDT was detected in about 65% of specimens of BM, MS and Adp T and in about 40% of the umbilical serum specimens. There was only a significant positive correlation between total DDT residues in the BM and Adp T. Total DDT residues in umbilical serum and Adp T were significantly higher in the urban than in the rural mothers. The detection of some OCPs in maternal biological compartments suggests their potential placental and BM transfer to her child during pregnancy and lactation, respectively. Furthermore, it might reflect the persistence or recent use of these pesticides in the environment.