Lack of effects of polychlorinated biphenyls on testosterone synthesis in mice.

Male mice were exposed to two different preparations of PCBs. The pure congener 2,2',4,4',5,5'-hexachlorobiphenyl (6-CB) was given at daily doses of 4, 20, and 40 mg/kg b.wt. during the perinatal or pubertal period. A technical mixture of PCB (Clophen A50) was administered during puberty at daily doses of 8, 40, 80, 120, and 160 mg/kg b.wt. Treatments were, in the different experiments, carried out every second or third day for three to five weeks. Treatment during puberty was started when the mice were 5 weeks old. The perinatal exposure was started on day 13 of gestation and ended on day 24 post partum. There were no significant differences in the plasma levels of testosterone between the treated mice and the controls after any of the treatments, but there was an increase in the relative testes weights for the animals treated perinatally. No influence on the biosynthesis of testosterone in the testicular interstitial cells in vitro could be demonstrated.