New study indicates chemicals from grocery stickers may be leaching into foods. Here's what you need to know

The next time you're in the grocery store, you may want totake a look at how the fresh food ispackaged.

According to new research, toxic chemicals similar tobisphenol A (BPA)are leaching from certain labelsthrough packaging, and into the meat, seafood, produceand other foods purchasedin some Canadian and U.S. grocery stores.

"We identified the thermal labelsare a source [of BPA-like compounds] in our diet directly ... so far in the world, no one had identified that the packaging could be a source of bisphenol S to the diet," saidStphaneBayen, a professor atMcGill University in Montreal andsenior author of the newly published study.

Bisphenol S (BPS) and BPAhave been studiedfor their possible effects on health. Research has shown their ability todisrupthormones and have negative effects on growth, brain function, the reproductive systemand theimmunesystem.Bisphenols have many applications and are frequently used in the manufacturing of various plastics and thermal paper.

Over the past decade, Canada has tightened its BPA regulations in an effort to phase out its use, including makingit illegal to manufacture, import, advertise or sell baby bottles that contain BPA.

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Meanwhile, BPSand other compounds highly similar to BPA remainunregulated andhave been adopted as substitutes by the industry for various products, including thermal food labels where you can find the price, best-before data, ingredients and other information on foods packaged in store.

As we've done more research into bisphenols ... the safety levels have consistently been lowered as we discover more and more about how these compounds work.- Glen Pyle, molecular cardiologist at the University of Guelph

Scientists have long warned that regulatingBPAalone may not be makingproducts any safer. Research at the University of Guelph in Ontario suggestsBPS has similar effects to BPA on the heart, and literature reviews that synthesize available research have concluded BPS is equally or "more toxic."

Though BPA free, the thermal labels examined in the studyby Bayen and his colleagues found they contained and transferredhigh amounts ofrelated compounds including bisphenol S (BPS)that are known to have similar effects on humans as BPA.

"Only a few[researchers]detected bisphenol S in food before [but]the source was completely unknown," Bayen said.

BPSlevel over22 times higher than EU limit

The McGillstudymeasuredthe concentrations of BPS and other BPA substitutes in labels, packaging and products purchased in stores. The research was published in March in the journal Environmental Science & Technology, with funding fromthe Canadian Institutes of Health Research and the Canada Foundation for Innovation.

Grocery stores often use thermal food labels, which contain BPS to allow the paper to change colour when exposed to heat.

The McGill researchers collected a total of 140 samples of food packaging materials from grocery stores in Canada (Montreal and Victoria) and the U.S. The materials in question, such as thermal labels, are used in almost all grocery stores.

They tested the materials and the food inside for several BPA-like compounds, then measured their migration from the labels into fish from each store experimentally.

The results clearly showed that BPSand other BPA-like compounds wereleachinginto the food from the thermal labels, while other packaging did not appear to be a significant source.

"The levels in which they found it ...exceeded the levels recommended by the European Union," saidGlen Pyle, a molecular cardiologistat the University of Guelph who was not associated with the study. Pyle was part of the team that researched the effects of BPS on the heart.

CBC reached out to Health Canada to comment on the latest research. In a statement, the federal departmentsaid the amounts of BPS in food are "currently monitored" and "arenot considered to pose a health concern based on estimates of dietary exposure."

However, the data used to reach this conclusion does not seem toinclude fresh food.The statement linked to a series of reports by the Canadian Food Inspection Agency (CFIA), which tested canned food for various bisphenols, including BPS, and generally found little to none nothing like the levels detected by Bayen and colleagues.

Health Canada did not comment on the levels of BPS measured in thisstudy.

Unlike Canada, the European Union specifically regulates the amount of BPS that can migratefrom packaging into food. Samples collected for the McGill studyfar exceeded those limits, withBPS transfermeasured at up to 23 times higher than the 50 nanogramper gram wet weight limit.

Canada does prohibit the sale of food in packaging that may transferharmful compounds to the contents. It is unclear what levels of BPS transfer would be in violation of that regulation.

Pyle said those EU limitsare evidence basedand adjusted as new research emerges.

"One of the interesting things thathasoccurred as we've done more research into bisphenols is the safety levels have consistently been lowered as we discover more and more about how these compounds work and the health risks they pose to humans."

How to minimize exposure to BPS

There are ways to reduce your exposure to BPS, said theexperts who were interviewed. But they noted that thermal labels are widely usedand a lack of regulation in Canada makes it difficult to know what contains the compound.

Their recommendations include:

• Bagging produce yourself rather than purchasing pre-packaged produce with thermal labels.
• Pickingup your meat from the butcher counter.
• Bringing your own container or aluminum foil and asking for it to be used to package fresh meat or fish.
• Askingto have the label placed under theStyrofoam tray instead of on top(as researchers found that the parts of fish directly under a label had higherconcentrations of BPS and other chemicals).

"Unfortunately, since the pandemic, we find every fresh food now is [packaged] in these trayswith the thin film on top of itmeat,fish, seafood products but now you can also find this for dairy products, for bread, sometimes for vegetables," said Bayen.

This shift is an issue, Bayen said, since compounds like BPSseem to be able to migrate from thermal labels into all of these products.

Different stores varied in thelevels of BPSand similar compoundsin their labels.These other compounds the researchers detected included severalmembers of the bisphenol family that are not well known.

"We should also have a look at these chemicals, but there's no information at all on on what would be a safe level ... so a lot more work has to be done," Bayen said.

He feels thestudy also highlights some of the shortfalls of our current safety monitoring systems.

"The way surveillance works is that we always look [for] what we know... there is a need to to have all in our surveillance, to have tools that look for things that we didn't expect or we didn't know would be present."