Intrauterine Exposure of Human Newborns to PCBs (Polychlorinated Biphenyls): Measures of Exposure

摘要

The purpose of the present paper is two-fold: (1) to summarize what is known about the pre- and postnatal effects of an especially ubiquitous chemical compound, polychlorinated biphenyls (PCBs); and (2) to examine empirically some of the linkages proposed in an analytic model of PCB exposure in human infants. The linkages of interest are those between the source of contamination and the exposure of mother and infant. The present data are consistent with the notion that PCBs move through the environment and the human body into systems which may potentially threaten the infant both before and after birth. At this time it is not clear which of these exposures--prenatal (intrauterine) or postnatal (via breast milk)--has the greater impact on infant development. While the absolute quantity of PCB residues is substantially lower in cord serum than in breast milk, the fetal organism is particularly vulnerable during the prenatal period. One factor that has been overlooked in this debate is the size of the fetus. When PCB exposure is calculated on the basis of body weight, the infant's prenatal exposure is substantial.