Toxicity Studies on Polychlorinated Biphenyls in the Chick

INTRODUCTION POLYCHLORINATED biphenyls (PCBs) are a series of inert, chemically resistant plasticizers compatible with a wide variety of materials, such as paints, synthetic resins, varnishes and waxes and are used to improve such properties as chemical resistance, water resistance, adhesiveness and flexibility (Monsanto, 1968). Since PCBs appear extensively in the environment (Risebrough et al., 1968) and because of their chemical properties and widespread use, it appears important to study their potential effects on biological systems. Some work on the effects of PCBs on chickens has appeared in the literature. McCune et al. (1962) observed that an epoxy-resin paint caused symptoms of “chick edema” when chicks were placed in the battery before the paint had hardened. Subsequent investigation revealed that the amine hardener was the cause and that one of the components, a chlorinated biphenyl (Aroclor 1242*), seemed to be the problem compound. Levels of 100, 200, 400 and 800 p.p.m.…