In 2019, SIRC completed and published an updated comprehensive human health risk assessment as a capstone to our 30-year research program and to update the 2002 Harvard risk assessment. The project, like all SIRC-funded research, serves to fulfill our product stewardship mission.
SIRC’s goals were to review the scientific literature on styrene, develop hazard and exposure assessments, and assess potential toxicological risk – with a focus on workers in environments where styrene is made or used in manufacturing as well as the general population from environmental and consumer exposures.
Distinct areas of study included: cancer and toxicity to the nervous system, immune system, and reproduction and development. Independent scientists with relevant expertise were contracted for the various sections of the project.
Major conclusions of the project:
- Consumer products made with styrene remain safe. There is low concern or risk from exposures to styrene through everyday use of consumer products.
- Both general population risks – for all age groups – and occupational risks are within acceptable ranges, except for a potential risk for workers without respiratory protection in open molding in fiber-reinforced polymer composite (FRP) operations.
- There are no strong or consistent indications that styrene causes any form of cancer in humans. Although some studies suggest that styrene-exposed workers may be at increased cancer risk, the human evidence for styrene carcinogenicity is inconclusive.
The completed assessment was published by the Journal of Toxicology and Environmental Health, Part B: Critical Reviews in July 2019.