Comparative toxicity of polychlorinated biphenyls and dibenzofurans in rats

Abstract

Comparative Toxicity of Polychlorinated Biphenyls and Dibenzofurans in Rats. Oishi, S., Morita, M., and Fukuda, H. (1978). Toxicol. Appl. Pharmacol. 43, 13–22 (1978). The toxic effects of polychlorinated biphenyl (PCB) mixtures and polychlorinated dibenzofurans (PCDFs) were compared on male SD-derived rats fed diets containing 100 ppm of PCB and 1 or 10 ppm of PCDF for 4 weeks. Rats fed 10-ppm diets of PCDF developed chloracne-like lesions on the ears within 3 weeks. PCDF markedly and PCB slightly depressed body weight gain. In rats fed diets containing 10 ppm of PCDF, significantly decreased thymus, ventral prostate, and seminal vesicle weights were found. Hemoglobin and hematocrit values were decreased in rats fed either diet containing PCDF. PCBs produced very minimal effects on thymus and accessory sex organ weights and hematologic values. Both PCB and PCDF increased serum cholesterol concentrations and cholinesterase activity and decreased triglyceride concentrations and leucine aminopeptidase activity. PCDF decreased serum glutamic-pyruvic transaminase activity and testosterone concentration in testis, and increased serum glutamicoxaloacetic transaminase activity. These results suggest that, in the rat, PCDFs are more toxic substances than PCBs when administered in the diet.