NIOSH Seeks Comments on Revising Carcinogen Policy
Sept. 22 is the deadline. The agency's request poses several questions, including whether a 1 in 1,000 working lifetime risk for workers should be the target level for recommended exposure
NIOSH has opened a comment period to hear from stakeholders as it revises its Carcinogen Policy, which the CDC agency uses to classify carcinogens and set recommended exposure limits (RELs). A major limitation in the policy is the use of the term "Potential Occupational Carcinogen," which dates to the 1980 OSHA hazard classification for carcinogens in 29 CFR 1990.103, the agency's notice states.
NIOSH has created a new Cancer and REL Policy Web Topic Page with details of its plans and updates about the revision process. The notice says NIOSH wants to examine technical and scientific issues with the current policy, including these questions:
- Should there explicitly be a carcinogen policy as opposed to a broader policy on toxicant identification and classification (e.g., carcinogens, reproductive hazards, neurotoxic agents)?
- What evidence should form the basis for determining that substances are carcinogens? How should these criteria correspond to nomenclature and categorizations (e.g., known, reasonably anticipated, etc.)?
- Should 1 in 1,000 working lifetime risk (for persons occupationally exposed) be the target level for a recommended exposure limit for carcinogens or should lower targets be considered?
- In establishing NIOSH RELs, how should the phrase "to the extent feasible" (defined in the 1995 NIOSH Recommended Exposure Limit Policy) be interpreted and applied?
- In the absence of data, what uncertainties or assumptions are appropriate for use in the development of RELs? What is the utility of a standard "action level" (i.e., an exposure limit set below the REL typically used to trigger risk management actions) and how should it be set? How should NIOSH address worker exposure to complex mixtures?
NIOSH says limitations in the current policy prompted the 2010 decision to revise it. "A major limitation in the policy is the use of the term 'Potential Occupational Carcinogen' which dates to the 1980 OSHA hazard classification for carcinogens outlined in 29 CFR 1990.103 and is defined as 'any substance, or combination or mixture of substances, which causes an increased incidence of benign and/or malignant neoplasms, or a substantial decrease in the latency period between exposure and onset of neoplasms in humans or in one or more experimental mammalian species as the result of any oral, respiratory or dermal exposure, or any other exposure which results in the induction of tumors at a site other than the site of administration. This definition also includes any substance which is metabolized into one or more potential occupational carcinogens by mammals," the notice states, adding that a major limitation of this definition is that the policy allows for only one cancer category, "potential occupational carcinogen."
"The adjective 'potential' conveys uncertainty that is not warranted with many carcinogens such as asbestos, benzene, and others," according to the agency. "This policy does not allow for classification on the basis of the magnitude and sufficiency of the scientific evidence. In contrast, other organizations, such as the International Agency for Research on Cancer (IARC) and the National Toxicology Program (NTP) allow for a more differential classification. The revision of the NIOSH Carcinogen Policy also coincides with the international realization that there is a need for more efficient and quicker means of classifying chemicals."
To comment, send an email to [email protected] and identify docket number NIOSH-240.