PCB 118 induces ultrastructural alterations in the rat liver

Polychlorinated biphenyls (PCBs) are ubiquitous environmental contaminants that bioaccumulate in the food chain and thus pose a health risk to humans and other animals. In this study, PCB 118 was added to the diets of Sprague Dawley rats for 13 weeks in concentrations of 2, 20, 200, 2000 p.p.b. to the females and 10, 100, 1000 and 10000 p.p.b. to the males. The chemical was dissolved in corn oil; animals that served as the control received corn oil in the diets devoid of PCB. Use of transmission electron microscopy and stereology revealed significant (P<0.05) elevation in the mean volume fraction of smooth reticulum profiles (20 p.p.b.), peroxisomes (200, 2000 p.p.b.) and lipid droplets (2000 p.p.b.) in the females. Hepatocytes from the males exhibited a significant increase in the mean volume fraction of lipid droplets at 10000 p.p. b. (P<0.05). Interactions between large quantity of estrogen and the PCB probably would account for more profound alterations in the liver of female Sprague-Dawley rats than in the males.