Researchers at McGill University report that several chemicals used as substitutes for bisphenol A in grocery price labels can migrate into food and disrupt key processes in lab-grown human ovarian cells. The findings, published in Toxicological Sciences, add to concerns that “BPA-free” labels do not necessarily mean safer materials.
A study led by McGill University researchers is raising fresh questions about the safety of chemicals used in some “BPA-free” food packaging, particularly the thermal-paper developers used in grocery price labels.
The work focused on chemicals that can be present in price stickers attached to packaged meat, fish, cheese and fresh produce. Building on earlier McGill research published in 2023, the researchers said chemicals used in label printing—including bisphenol S (BPS), a common substitute for bisphenol A (BPA)—can migrate through plastic wrap and end up in food.
In the new experiments, the team exposed lab-grown human ovarian cells (KGN granulosa cells) to four widely used BPA alternatives: TGSA, D-8, PF-201 and BPS. The researchers reported “early warning” signs of potential toxicity: TGSA and D-8, in particular, led to fat droplet buildup inside cells and altered the activity of genes involved in cell growth and DNA repair.
“These are major cellular functions,” said Bernard Robaire, a co-senior author of the study and a James McGill Professor in McGill’s Departments of Pharmacology & Therapeutics and Obstetrics & Gynecology. “Disrupting them doesn't prove harm in humans, but it gives us a strong signal that these chemicals should be further investigated.”
The peer-reviewed paper—titled “High-content imaging and transcriptomic analyses of the effects of bisphenol S and alternative color developers on KGN granulosa cells”—was authored by Lama Iskandarani, Stéphane Bayen, Barbara Hales and Robaire and appeared in Toxicological Sciences (Volume 207, Issue 2, pages 401–414). The study lists support from the McGill Sustainability Systems Initiative.
The researchers also cautioned against treating “BPA-free” as a blanket assurance of safety. “'BPA-free' is an incredibly misleading label,” Robaire said. “It usually means one bisphenol has been swapped for another, and there are more than 200 of them. Some may be just as harmful, or even worse. We need to test these compounds before they're widely adopted, not after.”
McGill said Health Canada has added the four chemicals examined in the study to a list of substances requiring further review.
For consumers looking to reduce exposure, Robaire advised removing price labels and plastic wrap from fresh foods before storing them. He also suggested choosing items from the top of grocery display stacks, saying pressure from products below could increase chemical transfer into food.
