NIOSH Actions Threaten Lower Exposure Limits for Carcinogens
The National Institute for Occupational Safety and Health (NIOSH), the workplace research arm of the federal Centers for Disease Control, recently has taken two actions likely to lead to much lower occupational exposure recommendations for known or suspected carcinogens. First, in December 2016, the agency finalized its new Carcinogen Policy. The new policy provides “that there is no known safe level of exposure to a carcinogen, and therefore that reduction of worker exposure to chemical carcinogens as much as possible through elimination or substitution and engineering controls is the pri¬mary way to prevent occupational cancer.” NIOSH no longer will use the term recommended exposure limit (REL) for chemical carcinogens; rather NIOSH will only rec¬ommend an initial starting point for control, called the Risk Management Limit for Car¬cinogens (RML-CA). For each chemical identified as a carcinogen, the RML-CA will be set at the level deemed necessary to ensure no more than one excess cancer case in 10,000 workers in a 45-year working lifetime. When measurement of the occupational carcinogen at the RML-CA is not analytically feasible at the 1 in 10,000 risk estimate, NIOSH will set the RML-CA at the limit of quantifi¬cation (LOQ) of the analytical method. This is a major change from the prior NIOSH policy, which recognized that acceptable exposure limits can be established for carcinogens and focused on risks of 1/1000 or greater.
Second, in March 2017 NIOSH published draft guidance for using Occupational Exposure Banding (OEB) to evaluate chemical hazards. The guidance would be used by NIOSH to establish and update RELs and the new carcinogen limits, and also appears intended to allow chemical users and others to set their own internal limits. It includes formulas for deriving upper and lower limit values (bands) on the basis of available data. The preferred databases for carcinogens include EPA’s IRIS listings and the Cal OSHA database, among others.
These two developments, taken together, are likely to lead to major reductions in NIOSH exposure recommendations for known or suspected carcinogens. While NIOSH has no enforcement authority, the NIOSH recommendations can be enforced by OSHA pursuant to the General Duty Clause of the Occupational Safety and Health Act, and they often are used as internal corporate standards.
The Carcinogen Policy is final; therefore, revision likely would require a petition for reconsideration. Comments on the OEB guidance are due by June 13, and could include arguments that it cannot be used to supersede current RELs and that the new Carcinogen Policy should not be applied.