Subacute Study of Rats Fed Ground Beef Treated with Aqueous Chlorine - Anatomic Pathology

This research evaluated the anatomic pathology of rats fed diets containing ground beef which had been treated with aqueous chlorine. The anatomic pathology of 240 rats fed 92 d with diets containing ground beef treated with 0, 50, 200 or 600 ppm chlorine was carried out according to National Institutes of Health bioassay pathology procedures. The major rat tissues were evaluated and the incidence of histopathological conditions was recorded. The inclusion of chlorine-treated meat in the diet was not associated with any increase in incidence of neoplastic lesions, inflammatory lesions or degenerative changes. However, all male rats fed the meat diet both with or without chlorine exhibited mild to moderate hepatic fatty metamorphosis. In all likelihood, the fatty livers were due to the high fat content of the diet (about 35%). The adrenal glands of the control and treated males exhibited fatty metamorphosis. This effect is not explained by diet because even the male rats on the commercial rat feed had fatty adrenal glands. Other histopathologic conditions such as focal hepatitis, triaditis, focal myocarditis, focal lymphocytic infiltration, chronic murine pneumonia, chronic tracheitis, focal acute gastritis, dacryoadenitis, cataract, hyperplastic hepatic nodule or ultimobranchial cysts, when found were not associated with any treatment or sex group. The treatment of ground beef with aqueous chlorine before incorporation into a diet fed rats for 92 d exhibited no apparent effect on the anatomic pathology of rats.