The National Institute for Occupational Safety and Health (NIOSH) has issued a draft current intelligence bulletin significantly updating its 35-year-old policy for classifying chemical carcinogens. NIOSH proposes to evaluate for occupational relevance the hazard assessments that have been made by the U.S. National Toxicology Program (NTP), Environmental Protection Agency (EPA) and the International Agency for Research on Cancer (IARC). If NIOSH finds the scientific basis of a carcinogen classification to be occupationally relevant, it will list the chemical as an occupational carcinogen along with the NTP, EPA or IARC classification.

NIOSH also will determine the appropriate carcinogen category under the Globally Harmonized System (GHS) classification system used by OSHA in its Hazard Communication Standard. 

NIOSH said this approach will allow it to develop recommended exposure limits (RELs), replacing its current practice of recommending that cancer-causing chemicals be reduced to the lowest feasible level. The RELs will be health-based and designed to keep exposures below a target cancer risk level of 1 in 1,000 over a 45-year working lifetime, NIOSH said. In addition, the technical feasibility of controlling exposures in developing RELs will no longer be considered. Rather, NIOSH will provide recommendations, which will note whether existing controls are available or effective, including alternative risk management practices. 

The changes regarding the RELs are especially significant since community advocates and tort attorneys often cite them to advance their particular agendas. Comments on the proposal will be accepted through February 13. Affected employers should weigh in.