Histologic and Ultrastructural Studies on the Hepatocarcinogenicity of Benzene Hexachloride in Mice2

Publisher Website
Google Scholar
Abstract
Histologie and ultrastructural studies were made on hepatocarcinogenesis induced in mice by the organochloride pesticide, benzene hexachloride (BHC). Mice were fed isomers of BHC (or 24 weeks and then killed. Nodular hyperplasia and hepatocellular carcinoma were observed in mice fed basal diet containing 500 parts per million (ppm) of the α-isomer of BHC (α-BHC) (100% incidence), 250 ppm α-BHC (79%), 250 ppm α-BHC plus 250 ppm β-BHC (93%), 250 ppm α-BHC plus 250 ppm γ-BHC (93%), or 250 ppm α-BHC plus 250 ppm δ-BHC (75%). However, diet containing other isomers, or combinations of 100 ppm α-BHC and these isomers, did not induce liver tumors. Histologically, liver nodules induced in mice by α-BHC were well-differentiated hepatocellular carcinomas or nodular hyperplasia. Cirrhosis was rare. Electron microscopic examination showed a marked increase in the smooth endoplasmic reticulum in the cytoplasm of cells in areas of hepatocellular carcinoma, with frequent nuclear and mitochondrial changes. Liver tumors were induced in mice only by α-BHC, whereas β-, γ-, and δ5-BHC had no synergistic or antagonistic effects on the induction of tumors by α-BHC.

This publication has 0 references indexed in Scilit: