The US Occupational Safety and Health Administration ( OSHA ) has set the permissible exposure limit ( PEL ) for cadmium at a time @-@ weighted average ( TWA ) of 0 @.@ 005 ppm . The National Institute for Occupational Safety and Health ( NIOSH ) has not set a recommended exposure limit ( REL ) and has designated cadmium as a known human carcinogen . The IDLH ( immediately dangerous to life and health ) level for cadmium is 9 mg / m3 .