The Food and Drug Administration, criticized by its own scientific advisers for ignoring available data about health risks posed by a chemical found in everyday plastic, said yesterday it has no plans to amend its position on the substance but will continue to study it.
The agency has been reviewing its risk assessments for bisphenol A, a chemical used to harden plastic that is found in a wide variety of products, from baby bottles to compact discs to the lining of canned goods. The chemical, commonly called BPA, mimics estrogen and may disrupt the body's carefully calibrated endocrine system.
BPA is found in the urine of more than 90 percent of the U.S. population, according to data from the Centers for Disease Control and Prevention. Scientists believe it is most easily ingested after leaching from plastic containers into food and drink. In September, the first large study of BPA in humans found that people with higher levels of bisphenol A had higher rates of heart disease, diabetes and liver abnormalities.
Over the past decade, more than 130 studies have linked BPA to breast cancer, obesity, diabetes, neurological problems and other disorders. Much of the new research suggests that BPA has an effect at very low doses -- lower than the current safety standard set by the FDA. The most prominent finding was by the National Toxicology Program, part of the National Institutes of Health, which reported that there is "some concern" that BPA may affect the brain and behavioral development of fetuses, infants and young children.
The FDA has maintained that BPA is safe, relying largely on two studies that were funded by the chemical industry.
In October, the FDA was faulted by its own panel of independent science advisers, who said the agency's position on BPA was scientifically flawed. The panel said the agency should revisit its assessment and take into account the studies it had ignored.
Yesterday, Laura Tarantino, director of the FDA's Office of Food Additive Safety, said the FDA will respond to that recommendation by performing additional analysis. She said she did not know if it would last months or years.
"I can't tell you when we will finalize this," she said. "There is a lot of work."
She said one aspect the agency will examine is the cumulative BPA exposure a person faces from numerous everyday items regulated by the FDA -- among them food and beverage containers, plastic medical devices such as tubing, and coatings on gel tablets.
Advocacy groups said the federal agency is squandering time and money.
"More years of research by FDA to determine what thousands of scientists worldwide already know about the toxic chemical is a waste of time, taxpayer dollars, and will place millions of babies yet to be born at risk," said Alex Formuzis, a spokesman for the Environmental Working Group.
Urvashi Rangan, senior scientist at Consumers Union, said the government ought to ban BPA in products intended for infants and children, whose developing bodies are thought to be most vulnerable to the impact of estrogen-mimicking chemicals such as BPA.
"This is science happening in slow motion," Rangan said. "There is a lot of evidence happening out here already to suggest vulnerable populations should not have to continue consuming BPA."
Political pressure on the FDA to ban BPA is growing. Several states have introduced bans of BPA in various products, and in the next Congress, Rep. Edward J. Markey (D-Mass.) and Sen. Charles E. Schumer (D-N.Y.) are expected to reintroduce bills to ban BPA. Canada declared BPA a "toxic substance" and plans to ban it from baby bottles. A coalition of health and environmental groups meeting with President-elect Barack Obama's transition team is pushing a BPA ban as a top priority.
A number of retailers and manufacturers, meanwhile, have been offering BPA-free alternatives.