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F.D.A. to Reconsider Plastic Bottle Risk

By JULIE SCELFO
Published: December 23, 2008

source: The New York Times

美國食品暨藥物管理局將重新考量塑膠瓶的危險性
David McNew/Getty Images

SAFE OR NOT? Questions surround the chemical bisphenol-A, found in bottles like these.

安全嗎?類似右圖的這些瓶子含有「雙酚A」(BPA)的化學成份。塑膠奶瓶內溶解物質「雙酚A」疑似會危害嬰幼兒健康,請家長持續關切此議題的後續發展。


WEEKS after its own advisory board accused the Food and Drug Administration of failing to adequately consider research about the dangers of bisphenol-A, found in many plastic baby bottles, plastic food containers and metal can linings, the agency has agreed to reconsider the issue.


The F.D.A.’s draft risk assessment in August, finding the chemical safe as it is now used, stood out against a tide of recent scientific opinion. The National Toxicology Program, part of the Department of Health and Human Services, has said there was reason to be concerned that BPA, as the chemical is called, could harm the brain, behavior and the prostate gland in fetuses, infants and children. Canada added the chemical to its list of toxic substances this year and has said it will ban BPA from polycarbonate baby bottles.


In September, a study published in the Journal of the

American Medical Association found that adults with high levels of BPA in their urine were more prone to heart and liver disease and diabetes.

More than 200 animal studies have linked ingesting minute amounts of the substance to a range of reproductive problems, brain damage, immune deficiencies, metabolic abnormalities, and behavioral oddities like hyperactivity, learning deficits and reduced maternal willingness to nurse offspring.


The F.D.A.’s position that current human exposure to BPA in food-packaging materials provides an adequate margin of safety appeared to be based on two large multigenerational

studies by research groups that received funding from the American Plastics Council, according to a letter sent to the F.D.A. by Representatives John D. Dingell and Bart Stupak, Democrats of Michigan.

Although the F.D.A. had reviewed other studies, only the two multigenerational ones met its guidelines for determining safety for human consumption, said Dr. Mitchell Cheeseman, deputy director of the agency’s Office of Food Additive Safety.


I don’t want to suggest that published studies are not valuable to F.D.A.’s safety assessmentthey are,” Dr. Cheeseman said. “But they lacked details about how the study was done, they don’t include all the raw data, so independent auditing can’t be done by agency scientists, and they have a variety of protocol limitations.”

The F.D.A.’s science board subcommittee on BPA, however, after receiving comments from an independent advisory panel, determined that the F.D.A. was wrong to disregard the large body of research showing health effects even at extremely low doses. The agency’s decision to reconsider was made public earlier this month.


This was the F.D.A. finally acknowledging that its assertion that BPA is safe may not be correct,” said Dr. Anila Jacob, a physician and senior scientist at the Environmental Working Group, a Washington-based advocacy group. “Still, we don’t think it’s enough. With millions of babies being exposed to this chemical on a daily basis, every day we continue to delay removing this chemical from baby products is another day millions of infants continue to be exposed.”

Makers of BPA say that the chemical poses no known risk to human health.


Some manufacturers have begun introducing products for infants and children that are BPA-free, but BPA-containing polycarbonate bottles are still widely available. Shannon Jenest, a spokeswoman for the consumer lifestyle division of Philips, one of the world’s largest producers of reusable baby bottles (under the Avent brand name), said that the company would rather let consumersdecide what works for their family.” Philips manufacturers Avent products with, and without, the chemical.


Although Philips has made no public announcement, the manufacturer recently notified retailers that it will no longer accept orders for polycarbonate baby bottles after Dec. 31. But the manufacturer has not pulled its polycarbonate bottles from store shelves. “If you’re not melting the bottle in the microwave,” Ms. Jenest said, “then we don’t believe there’s an issue with bottles that contain BPA.”


More than 2 billion pounds of BPA are produced each year. According to the Can Manufacturers Institute, more than 22 billion cans to be used for food and more than 100 billion cans for beer and soft drinks were produced last year. John Rost, a chemist and chair of the North American Metal Packaging Alliance, saysthe vast majorityof them are lined with a resin coating containing BPA.


The Environmental Protection Agency has calculated that adults and infants can consume 50 micrograms of BPA per kilogram of body weight every day over a lifetime with little appreciable risk of harm. Yet more than 40 studies have found health effects in rodents fed as little as 0.2 micrograms per kilogram of body weight, according to Frederick S. vom Saal, a reproductive endocrinologist at the University of Missouri, Columbia, and a leading BPA researcher.

Exposure to BPA is widespread. A study by the Centers for Disease Control and Prevention found it in the urine of nearly 93 percent of a sample population.