The California Office of Environmental Health Hazard Assessment (OEHHA) recently released a Proposition 65 fact sheet on styrene. As it has done for other chemicals on the Proposition 65 list, OEHHA is providing the public with this information in order to provide further context to Proposition 65 warnings.
Styrene is an industrial chemical that is used for manufacturing various products including synthetic rubbers, latex paints, and polystyrene plastics. Exposure can occur through various channels; styrene can be released into the atmosphere in indoor settings through paints and building materials and even through indoor technology such as 3D printers that use filaments containing acrylonitrile butadiene styrene or high-impact polystyrene. Industrial manufacturing may generate styrene through plastics and fiberglass construction. Styrene is also present in tobacco smoke and exhaust from cars.
OEHHA issued a notice of intent to list styrene in February 2015. OEHHA’s listing was based on the state’s determination that styrene may cause cancer according to the National Toxicology Program (NTP). In 2011, NTP 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 mechanism of carcinogenesis.” The report included studies that showed that styrene increased the rate of combined malignant and benign lung tumors in two strains of male mice and increased the chances of malignant lung tumors in female mice. In April 2016, OEHHA added styrene to the Prop 65 list based on the findings of NTP.
According to OEHHA’s fact sheet, styrene also may be released from polystyrene-based food containers and may come into contact with food. This statement may conflict with the FDA’s determination that polystyrene is suitable for use in contact with food. The FDA assessed the safety of polystyrene (the material used in the packaging) and styrene (the chemical that can be released upon contact) and concluded that it is safe for public use. The FDA has even approved styrene for use as a food additive, though it rescinded that approval because industry has abandoned the use of styrene as a food additive. OEHHA’s statement on styrene exposure from food containers may, unfortunately, trigger meritless Proposition 65 claims and result in unnecessary cancer warnings on polystyrene products.
Grimaldi Law Offices has been advising clients for over 20 years on chemical and product law. For knowledgeable advice and in-depth analysis on your chemical regulatory compliance obligations, contact Grimaldi Law Offices at (415) 463-5186 or email us at email@example.com.