Proposition 65 Looks at Asphalt
BY Sandy Lender
UPDATE: At the November 15 meeting of the Carcinogen Identification Committee in Sacramento, the panel’s health experts agreed that the further study of paving asphalt is a “low priority.”
By the time this issue is mailed, representatives of the California Asphalt Pavement Association (CalAPA) will have discussed the differences between roofing and paving asphalt emissions with members of California’s Office of Environmental Health Hazard Assessment (OEHHA) at its Nov. 15 Carcinogen Identification Committee (CIC) hearing. What’s happening is this: Members of OEHHA will soon make the annual update to the list of carcinogens in the state. They will prioritize chemicals/substances, as required by Proposition 65, also called the Safe Drinking Water and Toxic Enforcement Act of 1986. This year, “asphalt” is among the substances being considered for prioritization.
As of press time, the National Asphalt Pavement Association (NAPA), the Asphalt Institute and CalAPA had provided to OEHHA a well-researched comment letter explaining the differences between roofing asphalt emissions and paving asphalt emissions, sharing the findings of the 2013 International Agency for Research on Cancer (IARC) monograph evaluation, and debunking some of the other study results OEHHA had cited.
Readers of AsphaltPro are aware that roofing asphalts have higher application temperatures than paving asphalts, among other differences. NAPA, CalAPA and Asphalt Institute made very clear such differences in their comments, recommending that OEHHA evaluate paving asphalt emissions separately from roofing asphalt emissions. The organizations then made clear the findings of the IARC monograph and asked OEHHA to rely on those findings when evaluating paving asphalt emissions.
For readers who are new to the IARC evaluation, that agency completed its monograph in 2011 and published its findings in 2013, essentially classifying bitumen (asphalt) paving fume to be about as carcinogenic as your cell phone.
As of this writing, with the classification of asphalts under California’s Proposition 65 prioritization undetermined, industry members must rely on science to carry the day.
NAPA Vice President of Environmental, Health & Safety Howard Marks stated, “This is an important issue for the industry. Once a material is listed under California’s Proposition 65, green construction codes, state agencies and other entities typically rely on that listing and identify the material as a health hazard. A review of the current Proposition 65 list finds that only certain extracts of asphalt binder (or bitumen) are listed, leaving some confusion about the material’s proper designation. Hopefully the comments we submitted will convince OEHHA to avoid further misclassification of paving asphalt.”
What Marks alludes to as confusing is just that. In the paperwork OEHHA is reviewing to consider asphalt emissions, oftentimes data are listed without attribution to a specific industry sector or type of asphalt. For example, the current Proposition 65 list only identifies certain extracts of asphalt binder that could be a health hazard; those extracts are not used for paving. Similarly, in an instance where OEHHA’s information refers to study results using asphalt at temperatures up to 316oC, neither paving asphalt nor roofing asphalt applications should be part of the discussion. That equates to 600oF, and not something you’ll see loading into a haul truck.
With the CalAPA Environmental Committee and its Proposition 65 Task Force in the lead, members of the asphalt industry have a firm grasp of what needs to be done to assist the CIC in recommending a low priority—or no priority at all—for paving asphalt emissions. Together, they will press on with the message that paving asphalt emissions should not be recommended for priority listing by the CIC.
The Nov. 15 hearing will be webcast live. There is a link to video archives of webcasts at https://video.calepa.co.gov.