A trial to find appropriate animal models of dichloropropane-induced cholangiocarcinoma based on the hepatic distribution of glutathione S-transferases

摘要

1,2-Dichloropropane (DCP) is an organic solvent used in industrial processes as a raw material to produce propylene, carbon tetrachloride, tetrachlo-roethylene, and other chemicals. It is also used in paint removers and varnishes and as a chemical intermediate. Several cases of cholangiocarcinoma were reported in March 2013 in offset color proof-printing workers at factories using DCP and/or dichlorometh-aneu. A cleaning solvent containing DCP was the most suspected cause of these cases of cholangiocarcinoma, and DCP has been classified recently by the International Agency for Research on Cancer (IARC) Monograph Working Group as a compound carcinogenic to humans2). However, animals exposed to DCP did not develop cholangiocarcinoma in previous studies Exposure to DCP by gavage for 103 weeks showed increased rates of adenomas and carcinomas of the liver in both male and female mice and an increased rate of adenocarcinomas of the mammary gland in female rats.