Without requiring lab tests to determine their safety, the U.S. government has approved thousands of chemicals for use in such products as sofa cushions, soaps, paints and baby bottles.
On average, two more chemicals are approved every day.
The result: consumers are unwittingly part of a kind of vast, uncontrolled lab experiment.
“We’re treating (people) worse than lab rats,” Karen Florini, an attorney with the non-profit group Environmental Defense said. “At least with lab rats, somebody bothers to collect the data.”
The U.S. system of regulating chemicals is under renewed scrutiny as European officials voted last week to adopt much tougher rules, which would require substantial testing of many substances before they can be sold there.
With growing amounts of synthetic substances detected in human blood and breast milk, U.S. critics have stepped up calls for similar rules here.
Chemical makers counter that the European proposal would cost billions, stifling research in an industry whose products are overwhelmingly safe and perform valuable functions in society. With strong support from the Bush administration, the companies favor a more voluntary approach toward testing.
As the debate continues, new concerns emerge regularly:
Polybrominated diphenyl ethers, used as flame retardants, have been linked to brain damage and lower fertility in lab animals. The amounts in human breast milk in the United States are doubling every two to five years, in some cases nearing levels linked to health problems in animals.
In a rare move Monday, the chief U.S. maker of two such chemicals agreed to stop making them by the end of 2004.
Bisphenol-A, used in baby bottles, dental sealants and linings of food cans, has been tied to lower fertility in rats and defective chromosomes in mice eggs.
Perfluorinated compounds, used to make Teflon pans and, formerly, Scotchgard, have been turning up in human blood and breast milk. Some members of this chemical family have been linked to cancer in lab animals; human risks are unclear.
Methyl tertiary-butyl ether (MTBE), a gasoline additive that reduces air pollution, readily infiltrates groundwater because of its high solubility. It is linked to cancer in mice and is labeled a potential human carcinogen.
With most chemicals, there is no proven risk to humans; manufacturers often sponsor research that contradicts the findings of possible risk.
And in most cases, that’s the end of the story.
Even if health concerns are raised after a chemical is on the U.S. market, the government often does not require that it be tested in any systematic way.
And manufacturers can continue making it for years.
When companies do come across possible risks, they must submit data to the U.S. Environmental Protection Agency. But companies can – and for most new chemicals, do – claim that the information is confidential.
As a result, the information is never available to the public.
This system for screening chemicals, enacted 27 years ago, allowed continued production of the 62,000 chemicals then in use and required little, if any, lab testing for the 18,000 approved since then. (Other laws govern chemicals in pesticides, food and drugs, which do require tests.)
EPA has the power to require testing of any chemical, old or new, which it believes may pose a “reasonable risk” to human health or the environment.
Yet the burden of demonstrating risk lies with the agency, a lengthy process that involves estimating exposures for each way a substance might be used. The agency rarely requires tests through this process; more often it negotiates with companies to conduct tests.
A 1997 EPA study found that of the 3,000 chemicals imported or produced in the United States in amounts above 1 million pounds, 43 percent had no publicly available data on toxicity.
Soon after, manufacturers volunteered to test these high-volume chemicals, an effort that is ongoing. Industry officials say they already had some data for most of the high-volume chemicals, though they concede it was not publicly available.
“This allegation that these chemicals haven’t been evaluated isn’t necessarily accurate,” Steve Russell, an attorney for the American Chemistry Council, an industry group, said.
Moreover, Russell said, most of the 80,000 approved chemicals are not made in significant amounts. Council officials estimate 15,000 chemicals are actively made, but could not provide an exact figure, nor could they say how many have been tested.
If requiring tests is hard, restricting a chemical’s use is even harder.
To take such action, the EPA must determine that any risks are not outweighed by a substance’s economic and societal benefits, again for each way in which it might be used. In practice, this provision is so difficult and expensive to implement that it is rarely used.
Restricting new chemicals is easier, through a 90-day screening process. Using computer models, the EPA predicts which new chemicals may be harmful by comparing their structures to those of existing substances _ yet again, safety data on the old chemicals can be limited.
“Just detecting something in the environment doesn’t mean it’s going to have any effect on human health, or on animal health,” Peter O’Toole, U.S. program director for the Bromine Science and Environmental Forum said.
Critics counter that evidence of harm will be elusive without required testing.
“How do you know?” Joel Tickner, an occupational health professor at the University of Massachusetts in Lowell said. “Unfortunately, the lack of proof of harm is very often misinterpreted as proof of safety.”