Neurobehavioral deficits have been observed in both animal and epidemiologic
studies of in utero exposures to polychlorinated biphenyls
Immunologic toxicity of dioxin and several congeners of PCBs have been
observed in animals, but human data for adults have provided little support.
The goal of our study is to examine PCBs, 2,3,7,8-tetrachlorinated dibenzo-dioxin
(TCDD), and dioxin-like toxic equivalence (TEQ) exposures in relation
to neurobehavioral and immunologic development in children.
How the study is being conducted:
The study will involve a cohort of births from two districts in eastern
Slovakia: one is Michalovce, where a chemical manufacturing plant that
operated from 1959 through the mid-1980s improperly discharged large quantities
of contaminated waste into the surrounding area; the other is Svidnik,
a comparative region without direct exposure to this pollution.
A total of 1200 mother-child pairs will be enrolled into the study. The distributions
of PCB congeners in umbilical cord and maternal serum collected at birth,
and in infant serum from 6 and 16 months of age. Metabolites of PCBs will
be measured in maternal serum. These determinants will be examined in
relation to immunophenotypes of lymphocytes, thymic size, post-vaccination
antibody titers, immunoglobulins, hearing, motor and cognitive impairment,
childhood morbidity, prenatal and postnatal growth, and thyroid hormones
in early life.