A new study published online on November 15, 2014 in the peer-reviewed journal Toxicology Reports evaluates genotoxicity of styrene oligomers extracted from polystyrene to be used in food contact materials (FCMs) (Nakai et al., 2014). The current recommendation by both the U.S. Food and Drug Administration (FDA) and the European Food Safety Authority (EFSA) is to use 50% ethanol solution as a fatty food simulant in safety assessments of polystyrene. Nakai and colleagues used acetone instead. Acetone was shown to extract greater amount of styrene oligomers (dimers and trimers) from polystyrene in comparison to ethanol. The researchers then used these high styrene oligomer concentrations for genotoxicity evaluation in vitro using the bacteria reversed mutation assay (AMES test, OECD test guideline No. 471) and the in vitro chromosomal aberration test (OECD test guideline No. 473). Both the AMES test and the chromosomal aberration test were negative. The authors therefore conclude that the risk of genotoxicity of styrene oligomers that migrate from polystyrene FCMs into food is currently very low.

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Nakai, M. et al. (2014). “Genotoxicity of styrene oligomers extracted from polystyrene intended for use in contact with food.