Decision on the New or Revised Occupational Exposure Limits for Formaldehyde and Styrene for 2009
At its meeting on July 14, 2009, the Board of Directors (“BOD”) approved that the current occupational exposure limits (“OELs”) for two substances – formaldehyde and styrene – be retained.
At issue was whether WorkSafeBC should adopt the American Conference of Governmental Industrial Hygienists (“ACGIH”) Threshold Limit Values (“TLVs”) or retain the current OELs for these substances.
The current OELs that are retained are as follows:
TWA: 0.3 ppm
Ceiling limit: 1.0 ppm
TWA: 50 ppm
STEL: 75 ppm
TWA = 8 hour time weighted average
STEL = 15 minute short term exposure limit
For both of these substances, there were:
- Comprehensive reviews of the research on the health effects;
- Meetings with employer and worker representatives;
- Consultations with stakeholders;
- Jurisdictional comparisons of OELs;
- Visits to workplaces that use these substances; and
- Analyses of claims data.
Discussion papers with the research obtained from the above were prepared and sent out for consultation with stakeholders in 2007.
Subsequently, for each substance, an independent peer reviewer was asked to:
- Review the scientific literature on the health effects at levels between the current B.C. OELs and the ACGIH TLVs; and
- Review the discussion paper to ensure it accurately reflected what was stated in the scientific literature on health effects.
For styrene, both the independent peer reviewer and the OEL Review Committee confirmed that the health effects outlined in the discussion paper were complete and accurate, and agreed that the current weight of evidence showed no adverse health effects at the B.C. OELs for styrene, or between the B.C. OELs and the ACGIH TLVs. They confirmed that at the current B.C. OELs, the weight of evidence showed that styrene is not a carcinogen, genotoxin or reproductive/developmental toxin. A summary of their findings along with the discussion paper previously sent out for consultation is available.
Similarly, for formaldehyde, both the independent peer reviewer and the OEL Review Committee confirmed that the health effects outlined in the discussion paper were complete and accurate, and agreed that the current weight of evidence showed no adverse health effects at the B.C. OELs for formaldehyde, or between the B.C. OELs and the ACGIH TLV. They confirmed that at the current B.C. OELs, the weight of evidence showed that formaldehyde is not a carcinogen, genotoxin, reproductive/developmental toxin, or cytotoxin. A summary of their findings along with the discussion paper previously sent out for consultation is available.
Further to the conclusions reached by the independent peer reviewers and the OEL Review Committee, the BOD made the decision to retain the current OELs for styrene and formaldehyde.
However, to ensure due diligence, the BOD directed the Policy and Research Division to report back to them on an annual basis with the following information regarding both styrene and formaldehyde:
- Results of any new scientific research – especially at the lower levels where the current OELs are;
- WorkSafeBC claims;
- Claims in other Canadian jurisdictions that are significant users of the substances; and
- Results of inspections by prevention officers.
Both styrene and formaldehyde continue to be designated substances under section 5.57 of the Occupational Health and Safety Regulation. As such, the requirements regarding substitution and an exposure control plan to maintain workers’ exposures as low as reasonably achievable below the exposure limit continue to apply for both substances.