Exposure standards for chemical used in bottles, food cans could lead to
Contra Costa Times, Douglas Fischer
Published April 21, 2007
Officially, Uncle Sam filters all decisions through the lens of improved children's health. But in practice, some federal decisions subvert that, critics note.
Take bisphenol-a, a chemical developed as a synthetic estrogen in the 1930s. It never found much medical use, but industry chemists in the 1950s somehow discovered bisphenol-a's nifty ability to make plastic shatterproof. Today the compound is found in baby bottles, Nalgene drink bottles and other hard plastic products. It's also used to line tin food cans.
Scientists lately have raised many troubling questions about the compounds' abilities to scramble chromosomes and impair reproductive health. Yet bisphenol-a has skirted President Clinton's 1997 executive order asking all federal agencies to focus on improving the well-being of children.
"How is the government responding? It's not," said Joy Carlson of Oakland, who co-founded the Children's Environmental Health Network
In the past few years, researchers studying laboratory animals have found that bisphenol-a acts like a hormone at exquisitely low levels, scrambling chromosomes and impairing future reproductive health in the very young. In March two environmental watchdog groups published two different reports noting that bisphenol-a leaches from bottles and food cans at levels near those causing harm in animals, putting many Americans, particularly children, at risk.
Manufacturers use 6 billion pounds of bisphenol-a each year, yet the agency charged with setting exposure standards to date has found no problems with its use.
That agency is an obscure arm of the National Institute of Environmental Health Sciences called the Center for the Evaluation of Risks to Human Reproduction. It is in the midst of assessing the chemical's health risks.
In March, the Environmental Working Group announced it had found bisphenol-a leaching out of half of nearly 100 different samples of canned food tested. Bisphenol-a is often applied as a coating inside food cans to extend shelf life. But what caused the biggest stir in Congress was its report that the government's health assessment is being compiled by a contractor with ties to chemical companies manufacturing bisphenol-a.
"The whole review panel is working with a 400-page document that was compiled by an independent contractor," said Sonya Lunder, a researcher with Environmental Working Group. "You have babies drinking formula who are getting half the dose of lab rats showing permanent reproductive defects. This is a sign we need to do something more serious immediately."
In a statement, the National Institute of Environmental Health noted that the contractor, Sciences International Inc., was charged only with finding and sorting the hundreds of scientific papers published in recent years on bisphenol-a. It did not evaluate them or otherwise draw any conclusions about the science; that work will be done by government employees and scientists on the independent review panel.
Sciences International, the agency said, "does not have responsibilities that would directly influence the outcome of (agency) decisions" regarding the chemical. Nonetheless, the government "has implemented a thorough review of all aspects of the SI contract and the nature of services provided by SI."
And other governments, most recently the European Union last November, have looked at the same data and found no reason for worry.
"There's a huge amount of science," said Steve Hentges, executive director of the American Chemistry Council's polycarbonate bisphenol-a global group.
"It's been reviewed by governments and agencies worldwide, and they've all come out with the same range of conclusions."
The Environmental Working Group study of canned food -- canned beans, soup, tomato sauce, tuna -- found bisphenol-a in the food in 55 cans, with some of the highest exposures -- 10 to 18 parts per billion -- in chicken soup and infant formula.
Researchers find that feeding rats a daily dose of 20 ppb bisphenol-a alters their offspring's reproductive systems. The EPA's "safe exposure dose," set in 1998, is 50 ppb per day, and the U.S. Food and Drug Administration's assessment is based on fewer than 20 samples.
The aim in the United States is for exposures to harmful products to be from 1,000 to 3,000 times below levels that cause harm in laboratory animals.
"There's no margin of safety for the typical person who eats one canned food product a day," Lunder said.
Separately, Environment California measured the amount of bisphenol-a leaking from commonly used shatterproof plastic baby bottles. To simulate a bottle that's been repeatedly washed and dried in a dishwasher, it cooked the bottles at 176 degrees for 24 hours and found about the same amount of bisphenol-a leaching out as in food cans.
Hentges said both results are in line with other data being considered by the National Institute for Environmental Health panel.
The panel has suspended its work, citing the nearly 500 studies that need to be assessed. Meanwhile, two California Democrats, Sen. Barbara Boxer and Rep. Henry Waxman, have demanded to know more about the contractor's role in developing the 400-page assessment. The panel is due to resume discussion "in the next few months," according to the agency.
