Polychlorinated Biphenyls, Dibenzo-p-dioxins, and Dibenzofurans and Birth Weight and Immune and Thyroid Function in Children

Abstract

None of the publications reviewed provide clinical evidence that PCBs (polychlorinated biphenyls) and related chemicals adversely affect weight, immune, or thyroid function in infants or children born to healthy mothers. Birth weights of term infants fell within the normal range in all studies. The greatest difference between comparison groups was reported by G. G. Fein et al. (1984a, Intrauterine Exposure of Humans to PCBs: Newborn Effects, EPA-600/3-84-060, Environmental Protection Agency; 1984b, J. Pediatr.105, 315–320). P. R. Taylor et al. (1989, Am. J. Epidemiol.129, 395–406) reported smaller differences in occupationally exposed women and E. Dar et al. (1992, Environ. Res.59, 189–201) found that women with higher PCB serum levels had larger babies. S. Patandin et al. (1998, Pediatr Res.44, 538–545) found a negative association of PCB concentrations in maternal or cord plasma and birth weight of breast and formula-fed infants combined but not when breast-fed infants were analyzed separately. L. Rylander et al. (1995, Scand. J. Work Environ. Health21, 368–375) reported decreased birth weights with higher dietary intake of contaminated fish. Thus, correlations between PCB exposure or polluted fish ingestion and birth weight were inconsistent. Thyroid and immune function were also within the normal range. In none of the papers were normal laboratory reference values provided and overall the statistically significant differences accounted for little of the variance.