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.”
Several large groups of prominent scientists have publicly expressed serious concern about BPA. In 2006, 38 experts met at a workshop sponsored by the National Institute of Environmental Health Sciences. After analyzing more than 700 published studies, the group concluded, among other things, that current levels of BPA in people are higher than “safe dose” levels that have been established by the Environmental Protection Agency. This September, the National Toxicology Program expressed “some concern” for how current levels of exposure to BPA are affecting the brain, behavior, and prostate gland of fetuses and babies.
Not everyone trusts these conclusions, however, partly because scientists have had trouble replicating the results of many of the studies that find fault with BPA, according to Steven Hentges, a chemist from the American Chemistry Council, a plastics-industry group in Arlington, Virginia. “Repeatability is the hallmark of science,” Hentges says. “If you can’t repeat a study, you can’t rely on it.” What’s more, while hundreds of animal studies have been conducted and while researchers have noted connections between BPA exposure and implicated health problems in people, scientists have yet to find a way to directly test the effects of BPA on human reproduction: You can’t expose pregnant women to potentially harmful chemicals and then just see what happens.
In July, after an extensive review of the research, the European Food Safety Authority (Europe’s equivalent of the United States Food and Drug Administration), confirmed its previously stated view that people, including young children, metabolize and excrete BPA from their bodies more quickly than rodents do, making the chemical safe at current levels in polycarbonate products, even for babies. In August, the FDA released a draft report that came to similar conclusions. “It has become even more clear from a scientific and regulatory perspective,” Hentges says, “that there is no basis for banning BPA from [baby] products.”
Such statements leave many scientists, environmentalists, and consumer-safety advocates fuming. Dahl says the industry confuses the public by sponsoring studies that aren’t peer-reviewed and encouraging politicians to give equal weight to such research. “There is a whole analogy here with tobacco,” Wallinga adds. “The term is ‘manufactured uncertainty.’ The plastics industry is going about funding studies to try to throw doubt on conclusions from the scientific community.” He points to an analysis by researchers at the University of Missouri, who looked at 218 studies on BPA—204 funded by the government, 14 funded by industry. Of the government-funded studies, 93 percent demonstrated harm, while 100 percent of the studies funded by the plastics industry found no harm at all.
IN APRIL, Canada became the first and so far only country to ban BPA from baby bottles. At least a dozen states are in various stages of considering bills that would ban the chemical from kids’ products, including California, Maryland, New York, and Illinois. A federal bill was introduced last spring but went nowhere.
The Minnesota ban on BPA ultimately failed. But consumer advocates say the bill will be reintroduced at the legislature when the new session starts in January. State senator Rummel thinks it’s time for state governments to step in and protect citizens. “As far as I’m concerned, the U.S. government’s regulatory system is broken,” she said shortly after she introduced the bill last spring. “We now have toxic chemicals in baby bottles and children’s toys. That’s why I’m carrying this bill.”
A government ban on BPA may never come, but a variety of manufacturers (including Nalgene and Playtex Infant Care) are responding to pressure from consumers and reconfiguring their products to be BPA-free. Items made without the chemical are now advertising that fact in large letters on product packaging. And stores are rapidly responding to consumer pressure. Fifty percent of baby bottles sold at Target are currently BPA-free, says Target spokeswoman Leah Guimond, and the company plans to increase that proportion during the next year. Wal-Mart plans to stop selling baby bottles with BPA in its American stores early next year. Toys ’R’ Us is doing the same thing.
WHILE EXPERTS continue to debate the details, I am choosing to play it safe, along with a growing number of parents, women of childbearing age, and parents of girls who may some day bear children. Soon after the conference last fall, I traded my Nalgenes for stainless steel water bottles. I trashed the used baby bottles we had been given because I didn’t know if they contained BPA or not. And as my tummy grew, I stopped cooking with canned foods other than the Eden Organic brand (one of the few that offers some products in BPA-free cans).
These days, I am doing my best to keep BPA out of the body of my 6-month-old son. It isn’t easy: He gnaws on everything, so I buy wooden and cloth toys, and I research plastic spoons and teething rings to make sure I know what’s in them. He’s about to start on solid foods, which means checking out a whole new list of things that might make their way into his mouth.
During a recent trip to the Babies ’R’ Us to buy spoons and dishes for the big transition, I forgot to bring my “safe list.” I couldn’t remember which brands were made with BPA, and the choices made my head swim. Eventually, I asked a saleswoman for help. She told me to wait and within minutes, she returned with a printed list of bottles, dishes, and teething toys made without BPA. Obviously, store employees had fielded the question before.
Still, not everyone has the time, energy, or resources to weigh the many options, and that’s something that Rummel thinks needs to change. She expects to be pushing her colleagues to ban BPA again next session. “We go into a store and think what we buy for our kids is safe,” Rummel says. “This is the United States, for God’s sake. It should be safe.”
Emily Sohn lives in Minneapolis.