By Eunice J. Clark
California’s Office of Environmental Health Hazard Assessment (OEHHA) has announced it intends to list styrene (CAS No. (100-42-5) as a carcinogen under Proposition 65.
The agency’s announcement represents its third attempt to list the chemical in the last six years. OEHHA’s current proposal to list the compound is by Proposition 65’s the authoritative bodies listing mechanism.
OEHHA is basing its listing on the National Toxicology Program’s 2011 listing of the styrene in its 12th edition of the Report on Carcinogens (RoC). The report concluded that styrene is “reasonably anticipated to be a human carcinogen based on limited evidence of carcinogenicity from studies in humans, sufficient evidence of carcinogenicity from studies in experimental animals, and supporting data on mechanisms of carcinogenesis.”
OEHHA states that styrene’s inclusion in the 12th RoC “satisfies the formal identification and sufficiency of evidence criteria in the Proposition 65 regulations for styrene.”
OEHHA first noticed its intent to list styrene in 2009. The agency’s original listing was challenged by the Styrene Information and Resource Center (SIRC) in July 2009 following the listing. In its complaint for declaratory relief, SIRC alleged that OEHHA used “illegal underground” standards by listing styrene as a “chemical known to cause cancer” under Proposition 65.
Sacramento Superior Court Judge Shelleyanne Chang granted SIRC’s Motion for Preliminary Injunction, citing a potentially “devastating effect” the state’s listing would have on the $28 billion styrene industry, including its use in plastics employed in the transportation and sale of California agricultural products. In her ruling, Chang wrote that California’s $1.3 billion strawberry crop, its $285 million in raspberry sales and $30 million blueberry crop were among many fruit products that would be hit hard by the negative listing on “styrenic plastics.”
Judge Chang ruled that the designation of a product as a carcinogen, particularly associated with food, could have a devastating effect on that product’s use.
Once identified as a carcinogen, it would be difficult to undo such a designation in the event that the plaintiff were to prevail in this litigation.”
OEHHA’s second attempt to list styrene under the Labor Code Mechanism was promptly withdrawn by the agency in February 2013 the day after hosting a public workshop the day before at Cal/EPA headquarters. The workshop was scheduled at the request of APTCO, LLC of Delano Calif., one of the largest expandable polystyrene custom molders in North America.
OEHHA withdrew its listing proposal without explanation.
Pending litigation brought by SIRC to overturn NTP’s listing of styrene in the 12th RoC, was resolved in favor of NTP on May 28, 2013 by the U.S. District Court for the District of Columbia. Shortly after the court rendered its opinion, peer review of the NTP’s assessment of styrene by the National Research Council (NRC) vindicated the scientific integrity of NTP’s report.
In the interim period the federal Occupational Safety and Health Administration regulations were drastically changed, removing NTP as a definitive source for identifying chemicals for listing via the Labor Code mechanism. These changes make OEHHA’s sole option to list styrene via the authoritative bodies listing mechanism based on its listing in the 12th RoC.
The cases cited by this article are:
(Sac. Sup. Ct. Case No.2009-00053089) and Styrene Information and Research Center Inc. v. U.S. Dept. of Health and Human Services, D.C. Cir., No. 11-01079).