Sarah Stevens and colleagues from the Norwegian University of Science and Technology recently studied the chemicals migrating from food contact articles (FCAs) into food simulants and their potential to disrupt the human endocrine system and metabolism. Building on Stevens’ previous research measuring the total number of chemicals with the potential to migrate (FPF reported), the current study focused on which chemicals transfer to foods under realistic conditions and are thus relevant for human exposure.

The researchers tested 14 plastic FCAs from four European countries, representing prevalent polymer types. They investigated chemical migration to two food simulants: water (mimicking aqueous foods) and a 50:50 water-ethanol mixture (simulating fatty foods like dairy products, or highly alcoholic beverages). Using state-of-the-art approaches (i.e. non-target high-resolution mass spectrometry and reporter gene assays with human cell lines) they screened migrating chemicals and assessed the metabolism- and endocrine-disrupting activity of the mixture that migrated (i.e. the overall migrate).

Stevens et al. noted that “products containing more extractable chemicals also leach more into food simulant”. Seventy-three percent of the chemical features measured in the earlier extraction experiments also migrated to at least one food simulant, with many migrating to the water-ethanol mixture. Twenty-one percent of chemicals migrated to both water and the water-ethanol mixture, making human exposure likely. Matching these chemical features to the 16,000 known plastic chemicals (FPF reported) was challenging, with less than 2% identified. According to the authors, this “once more, highlights the large number of unknown plastic chemicals” humans are exposed to.

All samples activated at least two nuclear receptors, with water-ethanol migrates showing overall more activity than water migrates. The pregnane X receptor, crucial for energy homeostasis, was the most common target. Its activation could disrupt metabolism, potentially leading to hypercholesterolemia and cardiovascular diseases. Some migrates showed nonmonotonic dose responses, being active at low concentrations but less so at high ones, which is a typical feature of endocrine disruptors (FPF reported).

Polyvinyl chloride (PVC), polyurethane (PUR), and low-density polyethylene (LDPE) induced the highest toxicity and contained the most chemical features, like in Stevens’ previous study (FPF reported). “PVC and PUR are known to contain more additives and processing aids than other polymers”. The study also provided a list of chemical features for further identification, correlating with observed receptor activity. Notably, some known endocrine disruptors, such as triphenyl phosphate (CAS 115-86-6), could be tentatively identified from the priority list. However, many features could not be matched with known plastic chemicals, and no further toxicological information was available for tentatively identified substances.

The authors conclude that currently used FCAs contain and leach compounds that interfere with the endocrine system and the metabolism, questioning the suitability and safety of these materials for food contact. They state that “a more thorough understanding of the chemicals used or present in plastics… is essential for improving the identification of toxic plastic chemicals and ultimately creating safer plastics”.

 

References

Stevens, S., Bartosova, Z., Völker, J., & Wagner, M. (2024). ‘Migration of endocrine and metabolism disrupting chemicals from plastic food packaging’. Environment International. DOI: 10.1016/J.ENVINT.2024.108791

Read more

Ida Irene Bergstrøm (April 11, 2024). ’Harmful substances have been found in plastic food packaging – but do we ingest them?ScienceNorway.no

Martin Wagner, et al. (2024) ‘State of the science on plastic chemicals – Identifying and addressing chemicals and polymers of concern.’ DOI: 10.5281/zenodo.10701706

Other recent research

de Paula, L. C. P., Alves, C. (2024). ‘Food packaging and endocrine disruptors’. Jornal de Pediatria. DOI: 10.1016/J.JPED.2023.09.010

Hirani, R. N., Bare, J. L., & Mathis, C. (2024). ‘Health Risk Assessment of Consumer Products’. Human and Ecological Risk Assessment. DOI: 10.1002/9781119742975.CH11