The Chemicals Within

No government in the world has seen the need to do that yet. But two weeks ago, Michigan Rep. John Dingell, chair of the House Committee on Energy and Commerce, sent letters to seven manufacturers of infant formula asking if their cans were lined with BPA and if they had tested their products for it. In 2006 Whole Foods stopped carrying baby bottles made from polycarbonate plastic, which contains BPA. The chain now sells only BPA-free bottles and sippy cups.

Phthalates have also raised concern. The compounds are used to soften the plastics in products ranging from rubber duckies and vinyl shower curtains to certain medical tubing and IV bags. They are also found in hundreds of personal-care products, including many fragrances, body lotions, nail polishes and shampoos. Again, 30 years of data from institutions like the NIH and EPA point to potential problems in animals stemming from prenatal exposure, including abnormalities in the reproductive tract and a decline of sperm quality. Now there is a smattering of human studies, too. In 2006 Danish researchers found that higher levels of a particular phthalate in mothers' breast milk correlated with lower testosterone in male babies at 1 to 3 months of age. Similarly, Dr. Russ Hauser at Harvard studied roughly 500 men at a fertility clinic and found that those with higher levels of certain phthalates in their urine had lower sperm counts and sperm motility. A Swedish study of young military recruits, however, found no such correlation. These are all association studies—which by definition cannot prove cause and effect.

Other scientists are starting to look at what happens when these chemicals are combined. L. Earl Gray Jr., a research biologist at the EPA, has tested mixtures of two or more phthalates in animals. He deliberately selected doses of each that were too low to cause effects individually—yet found that as many as 50 percent of male rats who were exposed to the combination in utero developed abnormalities in the reproductive tract. In his latest study, he combined three phthalates with four pesticides and found that at the highest doses, the effects equaled those of a sevenfold dose of a single phthalate. "All the males were malformed," he says.

The toy industry contends that phthalates pose no danger, particularly a widely used one called DINP. This chemical "has been well studied here in the U.S. and in Europe and found to be safe specifically for kids' products," says Joan Lawrence, a vice president of the Toy Industry Association. She notes that companies cannot easily replace it because none of the potential substitutes "has its lengthy safety record." Nonetheless, last October, California Gov. Arnold Schwarzenegger signed a ban on the use of six phthalates in children's products sold in the state—though three of them, including DINP, are prohibited only in items that kids under 3 are likely to put in their mouths. In December, Toys "R" Us notified its vendors of its intention to comply with the California ban by Jan. 1, 2009, the date the law takes effect. Mattel is already in compliance.

Finally there are the flame retardants, PBDEs. They turn up in fabrics, upholstery, foam mattresses, circuit boards and the casings of computers and televisions—and apparently escape into indoor air and dust. Animal studies show they can have negative impacts on learning and memory, sperm counts and thyroid functioning in rats and mice. PBDEs tend to linger a long time in the body, and one mixture in particular seems "quite biologically active, especially during development, as we've seen in studies on rats, mice and fish," says Linda Birnbaum, director of experimental toxicology at the EPA. "If I were nursing my baby, I wouldn't stop because of PBDEs in breast milk, but many of us wish they weren't there." According to the EPA, 11 states—including California, Maine, Michigan and New York—have bans on two major types.

It could take decades to resolve doubts about the safety of all these chemicals, one way or the other. But Timothy June isn't waiting. He's stopped buying tomato sauce in tin cans to avoid the BPA, which scientists say tends to leach out of can linings when the contents are particularly acidic. He's ditched his vinyl shower curtain in favor of a cloth one. And he's considering getting rid of the foam mattress on his fishing boat. "I guess the survey had a bigger impact on me than I realized," he says. Let's all hope the chemicals aren't having an even bigger impact on us.

With Anna Kuchment

© 2008