Four former employees of a printing company in western Japan died after developing bile duct cancer, raising concerns about the use of chemicals at the plant. Shinji Kumagai, an associate professor at the University of Occupational and Environmental Health who was part of the team that uncovered the deaths, said chemicals used at the factory are the probable cause of the cancers. On 2 April 2013, Labour ministry investigators searched the Osaka head office of printing firm Sanyo-CYP Co amid long-running concerns about workplace cancers. A total of 17 employees had developed bile duct cancer, eight of whom died. A nationwide investigation subsequently identified 48 more cases.

Risks 557, 26 May 2012. Risks 600, 13 April 2013.