From the National Geographic, March, 2024, by Sharon Guynup:

Products that don’t contain bisphenol A may still contain “cousin” chemicals that can also harm the brain, liver, and reproductive system, and increase the risk of certain diseases.

Walking down any aisle in a supermarket, “BPA-free” labels declare food, water bottles, sippy cups, and other products to be clear of bisphenol A (BPA)—a chemical used in plastic and as a liner in food cans. Serious health concerns linked to BPA prompted manufacturers to synthesize dozens of chemical substitutes that are now incorporated into thousands of products. But are they safe?

BPA-free products are not free of bisphenol. They’re made with BPA “cousin” chemicals that share a nearly identical chemical structure—and similar health concerns. Many scientists call them “regrettable substitutes,” says Patricia Hunt, a reproductive biologist at Washington State University, Pullman.

“What was not really known at the time was that they were replacing BPA with BPS,” says Laura Vandenberg, an endocrinologist at the University of Massachusetts Amherst who studies the health impacts of hormone-disrupting chemicals.

Plastic first appeared on the market in the 1950s; today the world is swimming in them. But their convenience and affordability come with a cost. BPA found in clear, hard plastic is a known to disrupt the activity of natural hormones; specifically, it mimics the actions of estrogen and influences how the body develops and functions. Thousands of studies show that even in minuscule doses, BPA may harm the brain, liver, or the reproductive system in both men and women. It’s been linked to fertility problems, miscarriage, increased risk of diabetes, heart disease and more.

Exposure during early development is of particular concern, and BPA can cross the placenta, Hunt says.

In 2008, Canada declared the chemical ‘a dangerous substance. Four years later, in 2012, the U.S. Food and Drug Administration (FDA) banned BPA from baby bottles and sippy cups, then from infant formula packaging. With an onslaught of negative press, many manufacturers rushed to market “BPA-free” products.

The industry argues that BPA is benign. “The scientific evidence supporting the safety of BPA is robust and should not be dismissed,” an American Chemistry Council spokesperson wrote in an email.

However, the European Food Safety Authority (EFSA) disagrees. After reviewing more than 800 studies completed since 2013, the agency  reduced its previously recommended “tolerable daily intake” level—the amount considered safe in our bodies—by 20,000-fold. Under these new guidelines, a 154 pound-person would consume about 264 times the allowable levels of BPA in a standard can of tuna, according to El Pais, Spain’s newspaper of record.

The EFSA assessment raises serious questions about potential harm; whether government regulations are sufficient; and how to protect ourselves and our families.

National Geographic contacted the FDA to ask whether, in light of the EFSA assessment, it should reassess what exposure of BPA is safe. They did not respond by time of publication.

An indirect food additive

The FDA considers BPA “an indirect food additive” because it readily leaches into food from plastic packaging, takeout containers, plasticware, canned goods, and soda cans. The agency deemed some exposure safe for adults in 2014, though it didn’t include BPA substitutes in that  assessment.

Meanwhile, we are awash in plastic products, synthetic fibers, and resins. BPA and closely related chemicals are found in nearly everything: toys, water bottles, soaps, shampoos, medical devices and sports equipment, packaging, clothing (including sportswear, rain gear, and baby onesies), cars, cosmetics, electronics, upholstery, eyeglasses, paints, floorings and much more.

Even before signs of degradation appear, plastics exude chemicals.

“Our main route of [bisphenol] exposure is oral, mainly through food and water,” Vandenberg says. Packaging contaminates food; PVC pipes or landfills may pollute water with BPA. “The other major route is dermal,” she says, “absorbed through our skin.” BPA-family chemicals are omnipresent in personal care products. “We put them directly on our skin, sometimes in places where we’re going to absorb them easily, like our lips.”

Credit card and cash register receipts carry a substantial dose. They’re coated in BPA at levels 250 to 1,000 times higher than what’s found in a can of food. The European Commission banned BPA in thermal receipt paper in 2020; it’s still widely used in the U.S.

Hunt mentions another exposure route: We’re breathing these chemicals via microplastic dust.

A long history of harm

BPA has been around for more than a century. Russian chemist Aleksandr Dianin synthesized a new petroleum-based chemical, BPA, in his St. Petersburg lab in 1891. He could never have imagined that some 70 years later, it would launch a manufacturing revolution, and eventually, trigger serious worldwide health concerns.

In the 1950s, scientists combined BPA with other compounds, creating a clear, lightweight, plastic strong enough to replace glass. In an epoxy resin, it could line food and beverage cans. Ultimately, every imaginable industry found uses for BPA. It became a cash cow: production was valued at $23 billion in 2023.

Meanwhile, it was known back in 1936 that BPA mimicked estrogen: British researchers investigated the chemical as a possible drug treatment for women’s reproductive health problems. Though BPA’s future was in plastics, not medicine, it should have come as no surprise that it’s a hormone disruptor. Hormones, secreted by glands, act as chemical messengers that carry information and instructions between cells, influencing cell, organ, and body function.

Patricia Hunt was a pioneer, exposing potential harm when she documented pernicious health effects in lab mice in 2003. At the time, the chemical was already circulating in the veins of 93 percent of Americans.