The European Food Safety Authority (EFSA) has completed a re-assessment of the potential health risks associated with styrene in food-contact materials. In a draft scientific opinion, EFSA experts determined that styrene does not damage genetic material when ingested and that its presence in food-contact materials is safe if migration remains below 40 parts per billion (ppb). This preliminary opinion is open for public consultation until January 28, 2025, allowing stakeholders to contribute to the refinement of the final assessment.

The re-evaluation was requested by the European Commission following concerns raised by the International Agency for Research on Cancer (IARC). In 2019, IARC classified styrene and its primary metabolite, styrene-7,8-oxide (SO), as “probably carcinogenic to humans.” Despite this classification, styrene has been authorized for use in plastic food-contact materials under Commission Regulation (EU) No 10/2011, with no specific migration limit or restrictions. However, in response to evolving scientific insights, the European Commission now plans to implement a migration limit of 40 ppb for styrene in food-contact materials.

EFSA’s assessment focused on two key questions: whether styrene is genotoxic (i.e., capable of damaging genetic material) when ingested and whether its continued use in food-contact materials is safe under the proposed migration limit. The evaluation incorporated data from IARC’s 2019 monograph, research provided by the US Styrenic Information and Research Centre, and studies identified through a targeted literature search spanning 2018 to 2024. Additionally, EFSA considered data submitted by third parties in 2022 and 2023.

The review examined the potential for styrene to induce gene mutations, chromosome abnormalities, or DNA damage in rodents following oral exposure. All highly relevant and reliable studies yielded negative results, indicating no significant genotoxic effects. While two studies did report positive findings, they were deemed to have low relevance.

To further assess human exposure, EFSA examined biomonitoring studies involving workers in the glass-reinforced plastics industry, where occupational exposure to styrene is higher than in food-contact scenarios. However, these studies faced several limitations, including variability in exposure levels, potential co-exposure to other genotoxic substances, inconsistencies across studies, lack of dose-response relationships, and insufficient control of confounding factors. As a result, EFSA concluded that these studies did not provide sufficient evidence linking styrene exposure to genotoxic damage in humans.

Given the absence of genotoxic effects, EFSA’s guidance for food-contact materials suggests that migration limits up to 50 micrograms per kilogram of food pose no safety concerns. Consequently, the assessment confirms that using styrene in food-contact materials with a migration limit of 40 ppb does not present a risk to human health.