Researchers have discovered that some alternative materials designed to be an alternative to bisphenol A (BPA) could be leaching from plastic into foods, drinks, and other items contained in plastics.
This was a moment of déjà vu for Patricia Hunt, PhD, a professor at the Center for Reproductive Biology at Washington State University’s School of Molecular Biosciences, because 20 years ago she and her team uncovered that BPA could potentially seep through the baby bottles and resin containers many everyday Americans were using at the time and flow into their food and liquids.
Now Hunt and her team have published a new paper in Current Biology that reveals that bisphenol S, or BPS, which is a substitute for BPA, may do something similar.
Hunt told Healthline this experience was less a surprise than an “oh no, not again” moment. For her, this was the kind of result she was dreading.
Just like before, the researchers stumbled upon these findings by accident. They were looking into the reproductive effects BPA might have on lab mice.
The animals were placed in BPA-free plastic cages, with the test group given doses of BPA. Surprisingly, the mice in the control group — meaning they weren’t exposed to the chemical — were showing genetic abnormalities.
They found that BPS was filtering out of the cages and affecting the mice — just as its related chemical had done decades before.
For Hunt, it was frustrating given that this discovery essentially put her initial research on hold. She was aiming to see what BPA did to the “germline” — or the cells that give rise to eggs and sperm.
“When our control data shift, we simply can’t do experiments, so I knew we were out of business until we could figure out the source of contamination and eliminate it,” she explained in an email. “Unfortunately, this was more difficult than we anticipated.”
Throughout the mid-20th century, BPA became ubiquitous.
It’s found in polycarbonate plastics — used in containers, for example — and epoxy resins, which coat the inside of metal products like food cans, according to Mayo Clinic.
The onslaught of negative press generated by studies like Hunt’s led many manufacturers to ditch BPA — you’ll often see “BPA-free” on labels at your local supermarket.
But confusingly for consumers, the Food and Drug Administration (FDA) calls the chemical “safe.”
“Based on FDA’s ongoing safety review of scientific evidence, the available information continues to support the safety of BPA for the currently approved uses in food containers and packaging. People are exposed to low levels of BPA because, like many packaging components, very small amounts of BPA may migrate from the food packaging into foods or beverages. Studies pursued by FDA’s National Center for Toxicological Research (NCTR) have shown no effects of BPA from low-dose exposure,” the FDA writes on its website.
While this has been the official FDA position on the chemical over the past decade, just this month, it released the findings of a two-year study that doubled down on this, declaring that the compound in small doses is safe.
Hunt said that this has been frustrating for people in her field who feel regulatory agencies need to do a better job of listening to the concerns of outside scientists.
All of this back-and-forth between the scientific community and the FDA can be a headache for consumers unsure of what materials are safe or not in the supermarket aisles.
“It is impossible to simply stop using plastics altogether,” Hunt added. “But I’d like consumers to view plastic products differently. A plastic product showing physical signs of damage is likely degrading — which means it is releasing chemical components. Also, heat is an invitation for chemicals to migrate out of plastics, so putting these products into the dishwasher or microwave really isn’t wise.”
Tracey Woodruff, PhD, MPH, professor in the department of OB-GYN and director of the Program on Reproductive Health and the Environment at University of California, San Francisco, told Healthline that this new research reinforces the importance of having a more comprehensive approach to looking at these common chemicals available in the marketplace.
“This information is out there, but we still go to the store and we have to be able to shop and buy things with confidence,” said Woodruff, who was not part of Hunt’s research.
“What we are focused on is how the policy can be better on this. What I do with my personal life, for instance, is make choices in a case-by-case instance. I try to reduce my use of these microwavable materials. In my consumer choices, I’m always thinking ‘how can we have less of these potentially harmful materials for my family?’”
Woodruff said it’s also important that people take care of their overall health — eating well and exercising, for instance.
We can all do our part to boost our immune systems and work on our “resiliency” to handling these potentially harmful chemicals.
She emphasized that we do our research as consumers, reduce our chemical exposure, avoid putting these materials in the microwave, and work to improve our overall health.
For her part, Hunt added that she will be getting back to her original research to try to understand — and protect against — how chemicals like BPA (and now its replacements) could potentially impact reproductive health.
“I am also very interested in trying to understand how chemicals act and interact in mixtures. Instead of examining each chemical in isolation, we need to look at chemicals in the way we are exposed to them — a complex mix of chemicals,” she wrote.
“It stands to reason that combinations of chemicals will produce very different effects, and that’s something we need to understand.”
Researchers found that BPA-free plastics were still leaching out of material and causing abnormalities in lab mice.
The FDA does not consider BPA in plastic hazardous to humans. But experts say that they want more investigation into how these materials can affect human health as they leach out of plastics.