Washington – NIOSH has extended until Dec. 30 the comment period for its review of classifying carcinogens and related recommended exposure limit policies.
The agency also created a topic page with additional information on the effort.
Specific issues for comment include:
- Should the agency develop an explicit carcinogen policy, as opposed to a broader policy on toxicant identification and classification?
- What evidence should form the basis for determining if substances are carcinogens? How should these criteria correspond to nomenclature and categorizations?
- Should a 1 in 1,000 working lifetime risk for exposed people be the target level for an REL for carcinogens, or should lower targets be considered?
- In establishing the NIOSH RELs, how should the phrase “to the extent feasible” be interpreted and applied?
- In the absence of data, what uncertainties and assumptions are appropriate for developing an REL? What is the utility of a standard “action level” and how should it be set? How should NIOSH address worker exposure to complex mixtures?



