Immune cell counts and risks of respiratory infections among infants exposed pre- and postnatally to organochlorine compounds: a prospective study.

Background: Early-life chemical exposure may influence immune system development, subsequently affecting child health. We investigated immunomodulatory potentials of polychlorinated biphenyls (PCBs) and p,p'-DDE in infants.

Methods: Prenatal exposure to PCBs and p,p'-DDE was estimated from maternal serum concentrations during pregnancy.