A consultant with ORC Worldwide called the new NIOSH document a "good tool" for companies that work with hexavalent chromium, but said it did not justify a re-opening of OSHA's standard. The consultant noted OSHA had much of the information presented in the criteria document before publishing its final rule and that the agency had to consider factors NIOSH did not in establishing its REL, such as technical and economic feasibility.
A former key NIOSH official told Inside OSHA the difference in exposure limits is "significant" and said adopting the lower level could be justified to reduce worker risks, but also noted he could not think of an instance where a lower NIOSH REL had prompted OSHA to reassess one of its PELs. (OSHA did not respond to requests for comment about whether it would reassess its standard in light of the new NIOSH recommendation.)
NIOSH is proposing to lower its REL based on two new risk assessments, and will hold a public hearing on the document in Cincinnati on Jan. 22, 2009.
The new NIOSH criteria document lowers the REL for all hexavalent chromium compounds from the level of 1 µg/m3 established in 1988 to 0.2 µg/m3, a level which it says carries a 1/1,000 risk of cancer death to workers. NIOSH cites two risk assessments completed shortly before it commented on OSHA's rulemaking, one that studied chromate chemical production workers in Baltimore, Md., completed in 2004, and one that studied Plainsville, Ohio, chromate production workers completed in 2003 that it says demonstrate a "significant risk of lung cancer mortality to workers exposed to Cr(VI) at the previous NIOSH REL."
OSHA published its final rule regulating the chemical in 2006 with a PEL of 5 µg/m3 after a court-order mandated it develop a standard. According to the OSHA standard, the limit poses a 6/1,000 risk of cancer death to workers, but represents the lowest economically feasible limit the agency could set.
Source: Inside OSHA