Turns Out, Even BPA-Free Products Could Be Harmful

You know to avoid BPA — but have you heard of BPS? (Photo: David McNew/Getty Images)

In the backlash against bisphenol A (BPA) — an endocrine-disrupting chemical in plastics and other products linked to hyperactivity, obesity, and other health problems in animal and human studies — manufacturers have developed a host of “BPA-free” alternatives. But these choices, which often use chemicals similar to BPA, may be just as harmful, new research shows.

In a new study published in the Proceedings of the National Academy of Sciences, Canadian researchers exposed young zebrafish to extremely low doses of BPA and the common BPA alternative bisphenol S (BPS). (The experts chose zebrafish because they are neurologically similar to humans.)

When exposed to BPA early in life, the animals experienced a 180 percent increase in the number of neurons in the hypothalamus, a region in the brain associated with hyperactivity. The same experiment using BPS triggered a 240 percent increase, which may alter brain development and lead to behavioral problems later in life, says lead author Cassandra Kinch, a PhD student at the University of Calgary.

"The dose that we used is actually the same concentration that we find in rivers here in Alberta, Canada," Kinch tells Yahoo Health. "It’s actually 1,000-fold less than the tolerable intake rate set by the U.S. Environmental Protection Agency."

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BPS was created in response to pressure from consumers and governments to minimize human exposure to BPA, but was not exhaustively tested for safety before products with the compound began hitting shelves. “This chemical cousin to BPA was developed as a ‘safer’ replacement to BPA, but it acts similarly and is not any safer than BPA,” says Lisa Y. Lefferts, MSPH, senior scientist with the Center for Science in the Public Interest.

BPS is the most common BPA alternative, used in both receipts and plastics. A recent study of urine samples from the U.S. and seven Asian countries found that 81 percent of subjects had detectable levels of BPS in the body, and 93 percent had significant amounts of BPA in the body. Earlier research on a sample of 2,500 Americans revealed similar BPA figures, but did not assess BPS levels.

A 2013 study in Environmental Health Perspectives also found that BPS affects cells similarly to BPA. “These findings highlight the need for efficient in vitro screening methods to pretest possible substitutes for [hormone-disrupting chemicals] before they are deployed in manufacturing,” the study authors write.

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Manufacturers have increasingly offered BPA-free products over the past years. A groundbreaking study from the University of Texas, however, showed that most of these plastics still have potentially harmful chemicals that, like BPA, mimic the hormone estrogen. Chemicals with estrogenic activity have been shown to cause early puberty, lower sperm counts, and trigger other reproductive changes in mammals. They have also been linked to health problems including obesity and some forms of cancer.

The UT researchers purchased more than 450 different commercially available plastics, including food wraps, baby bottles, deli containers, reusable plastic food containers, and plastic bags. All together, they studied more than 500 plastics, since some of the products, such as baby bottles, came with several components.

Their findings were striking. Nearly every single product they tested — including every single one of the BPA-free plastics — leeched detectable levels of at least one estrogen-mimicking compound. Some of the BPA-free options even had more total hormone-disrupting chemicals than traditional BPA-laden polycarbonate.

The products were especially likely to leech chemicals when exposed to common stressors such as UV light, the researchers learned. Even when plastics are free of hormone-disrupting chemicals, the manufacturing process can alter the chemical composition or structure to change a safe plastic into one with hormone disruptors.

In fact, Kinch and her coauthors conclude that we should consider eliminating all bisphenols from consumer goods. ”BPA and BPS have very similar chemical structures, so since these two compounds look similar it follows that manufacturers would need to use another similar compound to make the plastics hard,” Kinch says. That includes not only BPA and BPS, but compounds known as BPB, BPE, BPF, and 4-cumylphenol — all of which may potentially be used to make plastics. Because manufacturers do not reveal the formulas for their products, Kinch explains, it’s difficult to say exactly which items include these chemicals.

When choosing water bottles, food containers, and baby bottles, glass is your best bet, Lefferts says. (Some metal water bottles are coated with linings that can leech chemicals.) Also, decline receipts for minor purchases; the thermal paper used to print them often contains BPS or BPA.

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