Neurobehavioral deficits at age 7 years associated with prenatal exposure to toxicants from maternal seafood diet.
To determine the possible neurotoxic impact of prenatal exposure to polychlorinated biphenyls (PCBs), we analyzed banked cord blood from a Faroese birth cohort for PCBs. The subjects were born in 1986-1987, and 917 cohort members had completed a series of neuropsychological tests at age 7 years. Major PCB congeners (118, 138, 153, and 180), the calculated total PCB concentration, and the PCB exposure estimated in a structural equation model showed weak associations with test deficits, with statistically significant negative associations only with the Boston Naming test. Likewise, neither hexachlorobenzene nor p,p'-dichlorodiphenyldichloroethylene showed clear links to neurobehavioral deficits. Thus, these associations were much weaker than those associated with the cord-blood mercury concentration, and adjustment for mercury substantially attenuated the regression coefficients for PCB exposure. When the outcomes were joined into motor and verbally mediated functions in a structural equation model, the PCB effects remained weak and virtually disappeared after adjustment for methylmercury exposure, while mercury remained statistically significant. Thus, in the presence of elevated methylmercury exposure, PCB neurotoxicity may be difficult to detect, and PCB exposure does not explain the methylmercury neurotoxicity previously reported in this cohort.
Institute of Public Health, University of Southern Denmark, Odense, Denmark. pgrand@health.sdu.dk
Philippe
P
Grandjean
Pal
P
Weihe
Flemming
F
Nielsen
Birger
B
Heinzow
Frodi
F
Debes
Esben
E
Budtz-Jørgensen
D000328:Adult; D002648:Child; D002653:Child Behavior Disorders / Q000139:chemically induced* / Q000175:diagnosis / Q000503:physiopathology; D003072:Cognition Disorders / Q000139:chemically induced* / Q000175:diagnosis / Q000503:physiopathology; D015331:Cohort Studies; D004785:Environmental Pollutants / Q000009:adverse effects*; D005260:Female; D005526:Food, Formulated / Q000009:adverse effects*; D006801:Humans; D008297:Male; D011247:Pregnancy; D011297:Prenatal Exposure Delayed Effects / Q000097:blood / Q000139:chemically induced* / Q000503:physiopathology; D017747:Seafood / Q000009:adverse effects*
D004785:Environmental Pollutants