PERINATAL EXPOSURE TO POLYCHLORINATED-BIPHENYLS AND DIOXINS AND ITS EFFECT ON NEONATAL NEUROLOGICAL DEVELOPMENT

Polychlorinated biphenyls (PCBs) and dioxins (polychlorinated dibenzo- p-dioxins (PCDDs), and dibenzofurans (PCDFs)) are widespread environme ntal contaminants which are neurotoxic in animals. Perinatal exposure to PCBs, PCDDs, and PCDFs occurs prenatally via the placenta and postn atally via breast milk. To investigate whether such an exposure affect s the neonatal neurological condition, the neurological optimality of 418 Dutch newborns was evaluated with the Prechtl neurological examina tion. Half of the infants were breast-fed, the other half were formula -fed, representing a relatively high against a relatively low postnata lly exposed group, respectively. As an index of prenatal exposure, fou r non-planar PCBs in cord and maternal plasma were used. These PCB lev els were not related to neurological function. As measures of combined pre- and early neonatal exposure, 17 dioxin congeners, three planar, and 23 non-planar PCB congeners were determined in human milk in the s econd week after delivery. Higher levels of PCBs, PCDDs, and PCDFs in breast milk were related to reduced neonatal neurological optimality. Higher levels of planar PCBs in breast milk were associated with a hig her incidence of hypotonia. This study confirms previous reports about the neurotoxic effects of these compounds on the developing brain of newborn infants.