Prenatal exposure to PCBs and infant performance on the Fagan Test of Infant Intelligence

A sample of infants was examined at conceptual age 67 weeks (6-month testin g, N=230) and again at conceptual age 92 weeks (12-month testing, N=216) us ing the Fagan Test of infant Intelligence (FTII). Analysis of the results r evealed a dose-dependent relationship between total umbilical cord-blood PC B levels and poorer FTII performance at both ages. A similar relationship w as observed using a subset of the persistent and heavily chlorinated PCB co ngeners associated with Lake Ontario fish consumption (septa-, octa-, and n onachlorinated biphenyls) in children tested at 12-months but not at 6-mont hs. These data replicate previous research (Jacobson et al., 1985) which de monstrated a dose-dependent relationship between prenatal PCB exposure and FTII performance in infants of Lake Michigan fisheaters. Analyses of FTII s cores with cord-blood DDE and maternal hair methylmercury (MeHg) revealed n o significant associations between FTII performance and either of these tox icants. The latter results replicate tt;lose of Myers et al., (1995) who fo und no effect of MeHg on FTII performance in Seychellois infants. (C) 2000 Inter Press, Inc.