Cholangiocarcinoma among printing workers

By June 2013, seventeen workers had suffered from intrahepatic or extrahepatic bile duct cancer (cholangiocarcinoma) in an offset proof-printing company in Osaka and nine of the workers had died. Ages at diagnosis were 25 to 45 years old. Known risk factors for cholangiocarcinoma were not found in the patients. All of the patients were exposed to 1,2-dichloropropane at high level for long-term and were diagnosed with cholangiocarcinoma 7 to 20 years after the first exposure. Twelve of the patients were also exposed to dichloromethane. The Japan Ministry of Health, Labour and Welfare recognized the cancer to be an occupational disease.