There is no evidence that the material styrene, often found in food contact materials, is genotoxic (has the ability to cause DNA or chromosomal damage).
That is according to the European Food Safety Authority (EFSA), which has ruled that the material is safe.
What is styrene?
Styrene is a colourless or light yellow liquid, often used in the production of plastics, including food contact materials.
Materials that commonly use styrene include polystyrene and styrene-acrylonitrile (SAN) resin.
Residues of styrene monomer have the potential to migrate into food from food packaging, although in very small quantities.
It is currently authorised for use in food packaging materials within the EU, in direct contact with food.
EFSA styrene safety findings: Is it truly safe?
The safety of styrene has been a source of contention for a number of years.
In 2018, the International Agency for Research on Cancer (IARC) suggested that styrene was ‘probably carcinogenic to humans’. Following this, the European Commission (EC) asked EFSA to reevaluate the genotoxicity of the material.
In 2020, EFSA published an opinion admitting uncertainties as to whether styrene was genotoxic after oral exposure.
In 2023, the EC asked for another reevaluation of its genotoxicity, as well as its safety for use in food packaging with the limit of 40 parts per billion (ppb) of styrene, the equivalent of 40 micrograms per kilogram of food (lower than the amount in the EFSA guidance).
After studying the effects of styrene on rodents, the EFSA concluded that there was ‘no evidence’ of genotoxicity in the substance after oral exposure.
Separate data suggest that humans are even less sensitive than rodents to styrene toxicity.