Earlier this year, six of the largest manufacturers of baby bottles agreed to stop using the chemical bisphenol A (BPA) in products sold in the United States. This announcement came amidst a flurry of studies exploring the toxic effect of the material in low doses, which has been shown to cause developmental delays, reproductive malfunctions and other health problems in laboratory tests. The material has already been banned from baby bottles in Europe and Canada, and several U.S. senators, including Sen. Charles Schumer of New York, have proposed similar bans in the U.S.

BPA has dangerous health implications, but it’s not the only chemical in consumer products to fall under scrutiny. So what draws public outcry and bans for one toxic chemical, while others slip safely under the radar?

“In the case of BPA, the tipping point was a perfect storm of activity,” says Mike Shade, PVC campaign coordinator for the Center for Health, Environment and Justice in Falls Church, Va.

He notes that the independent studies and testing of products with BPA, combined with the European and Canadian bans, and a September 2008 report from the National Toxicology Program (NTP) of the U.S. Department of Health and Human Services, indicating that there is still “some concern” that the plastic chemical may cause problems with development and health, all spun together to draw widespread national attention to this particular toxic chemical.

“One fact propelled more studies and that lead to legislation,” he says. “It created a ripple effect to push BPA out of the baby products industry.”

BPA is a success story for advocacy groups looking to educate consumers, manufacturers and retailers about the hidden harms in seemingly innocuous products. But it’s also an example of how the chemical safety system is broken, says Shade.

BPA may now be on the hit list of toxins that everyone knows to avoid – along with lead, DEET, and mercury. But what about the materials most consumers are completely unaware of, like polybrominated diphenyl ethers, or antimony, which are present in hundreds of consumer products and also have serious health implications.

“BPA is just one of thousands of chemicals that should be phased out,” Shade says. “But the law that was designed to protect us is broken and needs to be severely reformed.”

That law, the Toxic Substances Control Act (TSCA), is meant to regulate the introduction of new or existing chemicals into products, but it puts the burden of proof on the marketplace, not the developers, to prove risks, and it grandfathered in most existing chemicals when it was passed in 1976.

Rather than identifying one chemical at a time and trying to push consumer awareness and government regulation, most industry advocates would like to see a comprehensive approach to evaluating all of the materials used in products, with the onus put on manufacturers to prove materials and chemicals are safe before they can be used, and to set goals to replace those that aren’t.

But that would take far-reaching legislative oversight that doesn’t currently exist.

“There is no governing board that says, ‘This is what toxic material is’,” says Jay Bolus, vice president of technical operations at McDonough Braungart Design Chemistry (MBDC), an independent consultancy in Charlottesville, Va.  “That’s a huge problem, because it allows industries to drift to the lowest common denominator.”

“We need a wholesale change in the way we design and regulate products,” agrees Jeff Gearhardt, research director at the non-profit Ecology Center in Ann Arbor, Mich., and leader of HealthyToys.org, which tests children’s products for toxic materials. “Currently, the U.S. government doesn't require full testing of chemicals before they are added to most products.”

According to HealthyToys.org, the EPA estimates that among new chemicals to come out since TSCA, only about 15 percent include health or safety test data; and for existing chemicals, only five chemical groups out of 62,000 have been restricted in 29 years.