Polybrominated biphenyl-induced potentiation of chloroform toxicity.

ICR male mice were fed diets containing 0, 1, 25, or 100 ppm of polybrominated biphenyls (PBB) for 14 days prior to challenge with a single injection of chloroform (CHCl₃). Dietary PBB potentiated the CHCl₃-induced depression of p-aminohippurate accumulation by slices of renal cortex and the CHCl₃-induced rise in blood urea nitrogen concentration in a PBB-intake-related manner. The kidney weight-to-body weight ratio was elevated in PBB mice but not in mice consuming control (0 ppm) diet following administration of 50 μl/kg of CHCl₃. Mice ingesting food containing 100 ppm of PBB also exhibited a greater increase in serum glutamic-oxaloacetic transaminase activity than did control mice following CHCl₃ administration. The 24-hr LD50 of CHCl₃ in control mice was 1.28 ml/kg, while that in mice consuming 100 ppm of PBB was 0.62 ml/kg.