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FeedInfant Fears
Concerns about toxins in toys and baby products have some state lawmakers up in arms about a common ingredient in plastics. Will Minnesota be the first state to ban bisphenol A?
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I WAS THREE MONTHS PREGNANT, attending a conference at the Minneapolis Hilton last fall, when I first heard about bisphenol A. The hotel was filled with gynecologists presenting papers and talking about the latest research on reproductive health. I was there as a science writer, but I was already starting to think like a first-time mom, and one lecture in particular sent flutters through my abdomen.
The session was about how man-made chemicals affect reproduction. The latest chemical to come under scrutiny, one presenter said, was bisphenol A, also known as BPA. Rats exposed to extremely low doses of the chemical compound were having miscarriages, delivering babies with birth defects, and developing cancer. Human studies had yet to be conducted, she said, but several doctors at the meeting confessed they were concerned enough to consider recommending that their female patients avoid the chemical.
I didn’t know much about BPA at the time, but some online sleuthing revealed that I had already developed an intimate relationship with it. I learned that BPA was an integral ingredient in the Nalgene water bottles that I carried everywhere. It was in DVDs, blender bowls, even the lining of food and soda cans. And most alarming, it was in most baby bottles, sippy cups, and teething rings.
Bisphenol A is an extremely useful molecule, giving polycarbonate plastic products their hard, clear, almost glasslike feel. But the chemical leaches out of plastic when the material is heated, scratched, or chewed on. It gets into the environment and absorbed into our bodies. We eat it, drink it, and breath it in. A study published this year by the Centers for Disease Control and Prevention found traces of BPA in 93 percent of more than 2,500 people tested. The chemical shows up in breast milk, cord blood, saliva, urine and other fluids, including amniotic fluid.
Despite the growing sense of worry I heard at the conference, the status of BPA remains murky. Human data is lacking, for one thing. Plastics-industry representatives contend that the chemical is safe, and the U.S. Food and Drug Administration has gone so far as to issue public statements asserting that exposure to BPA from everyday objects is harmless.
Last winter, the debate over BPA’s safety surfaced in the Minnesota Legislature, when a pair of lawmakers introduced a bill that would’ve banned the chemical in products made for infants and children under 3 years old. The Safe Baby Products Bill, authored by state senator Sandy Rummel, of White Bear Lake, and state representative Karen Clark, of Minneapolis, initially met with broad support from a wide variety of legislators and committees. But the language regarding BPA was ultimately removed from the bill (which was then vetoed). Supporters say a version of the legislation will be back next session, and if it survives, Minnesota will be the first state to pass a BPA ban.
“At the end of the day, parents shouldn’t have to do research projects to find safe products for their children,” says Lindsay Dahl, a project coordinator at Healthy Legacy, an advocacy group that seeks to ban toxic chemicals in consumer products. “It’s up to the Minnesota legislature and the United States government to make sure products are safe and tested long before they hit store shelves.”
BPA BELONGS to a class of chemicals called hormone disruptors. Hormones, such as estrogen and testosterone, are the body’s messenger molecules. They help control growth, reproduction, development, and digestion, among other life-sustaining processes. In order to do their jobs, hormones must bind to mediator cells called receptors, and that’s where hormone disruptors like BPA get in the way. These man-made chemicals bind to the same receptors, blocking hormones from doing their jobs.
Scientists have known since the 1930s that BPA acts like estrogen in the body. Alarms about BPA, however, didn’t start ringing until just a decade or two ago, and even then, the warning signs were inconsistent. In the late 1990s, for example, geneticist Patricia Hunt was researching hormones in mice, when something went wrong with one of her experiments: Many of the mice in the control group (the ones that were supposed to be perfectly normal) had mutations in their eggs.
Hunt was puzzled and alarmed. After some sleuthing, she discovered that a janitor had used a harsh floor detergent to clean the animals’ plastic cages and water bottles, causing BPA to leach out of the plastic. Her findings sent Hunt down an unexpected research path: Subsequent experiments have shown that feeding BPA to pregnant mice causes birth defects, among other problems.
Animal and test-tube studies by other researchers around the globe have linked BPA to a variety of heath issues, including miscarriages, breast and prostate cancers, low sperm count, early puberty in girls, diabetes, obesity, ADHD, and much more. Fetuses and babies are especially vulnerable because hormones play a major role in their development. The reproductive system, also a hormone-directed set of organs, is likewise at risk.
There isn’t a single smoking-gun study that proves that BPA is a troublemaker—there are hundreds of them, says David Wallinga, director of the Institute for Agriculture and Trade Policy’s Food and Health Program, a fair-trade advocacy group in Minneapolis. “It’s most convincing when you look at [the research] as a whole,” he says. “What you see is not 200 studies that lead to reproductive issues or cancer, but 200 studies across a wide variety of endpoints. That’s what you would expect with something that interferes with hormone function.”
Particularly concerning, Wallinga says, are signs that even extremely low levels of exposure to BPA can wreak havoc on reproduction. “There’s an assumption that the more of something there is, the more dangerous it is,” he says. “What we’re finding with the new science is that this may not be the case for these kinds of chemicals.”
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