Styrene in Food Contact Plastics: EU Draft Sets a Specific Migration Limit of 0.05 mg/kg

Styrene, the monomer behind polystyrene and several other common food packaging plastics, is set to receive its first specific migration limit (SML) under Regulation (EU) No 10/2011. A draft Commission Regulation, forwarded to the Council on 20 October 2026, together with its Annex, introduces an SML of 0.05 mg/kg food, together with new guidance on how compliance should be verified. If the draft is adopted in its current form, operators using styrene-based plastics will need to make sure their testing and declarations of compliance reflect the new limit.

 

How Styrene Is Regulated Today

Styrene (FCM No 193) is listed in Annex I of Regulation (EU) No 10/2011 as an authorized monomer without an SML or any other specific restriction. This authorization goes back to a 1982 opinion of the Scientific Committee for Food, which placed it among substances for which no tolerable daily intake could be set but which could be used safely if residues in the material were kept as low as possible. Until now, migration has therefore only been covered by the general overall migration limit that applies to all substances.

The situation changed after the International Agency for Research on Cancer (IARC) classified styrene and its main metabolite, styrene 7,8-oxide, as probably carcinogenic to humans in 2018. The Commission then asked EFSA to assess whether the existing authorization was still safe.

 

What EFSA Concluded

The assessment came in two stages. In its 2020 opinion, EFSA found that the IARC conclusions could not be applied directly to oral exposure from food, but it could not rule out a genotoxicity concern. It estimated that styrene migration is below 0.01 mg/kg in most foods but can reach 0.23 mg/kg in some fatty foods and concluded that use without a migration limit could raise health concerns.

After a further request from the Commission in 2023, EFSA adopted a new opinion on 8 May 2025. It found no evidence that styrene is genotoxic after oral exposure and concluded that its use in plastic food contact materials raises no safety concern if migration does not exceed 0.05 mg/kg food. A proficiency test organized by the European Reference Laboratory also showed that official control laboratories can reliably verify compliance at that level. On this basis, the Commission proposes an SML of 0.05 mg/kg food.

 

How Compliance Will Be Verified

The draft also addresses how testing should be carried out, because styrene-based materials do not always behave in simulants the way they do in real food.

• Simulants, food or screening: For materials not yet in contact with food, compliance can be checked in food, in the food simulants of Annex III or through the screening approach of Annex V.
• Confirmation in food: EFSA noted that some simulants can produce much higher styrene migration than real food. If a material fails in a simulant or screening test, non-compliance must be confirmed by testing in food.
• Worst-case food: Styrene migration tends to increase with fat content. The food used for verification should therefore represent the worst intended and foreseeable conditions of use.

The draft itself notes that migration testing for styrene is not yet common practice, which is why it provides time to set up testing systems. Our guide to migration testing for EU plastic packaging explains how simulants and test conditions are selected under Regulation 10/2011.

 

 

Transitional Periods

If the new limit applies, the deadlines will run from the date of entry into force, 20 days after publication in the Official Journal. More specifically:

• 18 months: materials and articles that comply with the rules applicable before the change and are first placed on the market before this date can remain on the market until stocks are exhausted.
• 9 months: intermediate products and substances first placed on the market after this date that do not meet the new limit must state this in their declaration of compliance. They may only be used for materials and articles placed on the market before the 18-month date.

The 9-month rule is aimed at the supply chain. Converters who buy resins, sheets or semi-finished packaging should expect suppliers to update their declarations of compliance and they should check these declarations against their own production schedules.

 

Who Is Affected

Styrene is the building block of polystyrene (PS), high-impact polystyrene (HIPS), expanded polystyrene and copolymers such as ABS and SAN. In food packaging, these materials are widely used for dairy cups, yoghurt pots, trays, lids, clamshells and take-away containers. Since migration rises with fat content, packaging for dairy products, ready meals and other fatty foods will be the main focus of testing.

Resin suppliers and packaging converters will need to confirm that their products meet the new limit under realistic conditions of use and to update their declarations of compliance accordingly. Food producers using these materials should make sure they receive updated declarations from their suppliers.

 

Conclusion

The draft replaces an authorization that has relied on a general principle since 1982 with a measurable limit. For most foods, EFSA’s estimates suggest migration is well below 0.05 mg/kg, but fatty foods may come close to or exceed it. The draft still has to complete its scrutiny before publication, but the transitional periods will start soon after. Operators using styrene-based materials can use this time to identify the relevant products, plan testing in representative foods or simulants and align their documentation with suppliers.