April 22, 2008
A Hard Plastic Is Raising Hard Questions
By TARA PARKER-POPE
Are toxic plastics lurking in your kitchen?
It’s a question many families are asking after reports last week that a chemical used to make baby bottles, water bottles and food containers is facing increasing scrutiny by health officials in Canada and the United States.
The substance is bisphenol-a, or BPA, widely used in the making of the hard, clear and nearly unbreakable plastic called polycarbonate. Studies and tests show that trace amounts of BPA are leaching from polycarbonate containers into foods and liquids.
While most of the focus is on products for children, including clear plastic bottles and canned infant formula, the chemical is also used in food-storage containers, some clear plastic pitchers used for filtered water, refillable water bottles and the lining of soft-drink and food cans.
While there is debate about how much of a health worry BPA really is, retailers including Wal-Mart have said they are withdrawing baby products made with it. Nalgene, the maker of a popular sports bottle, and the baby-products maker Playtex have announced they will stop using it.
Here are answers to some common questions about BPA.
What is the evidence that BPA is harmful?
It all comes from animal studies. Rat pups exposed to BPA, through injection or food, showed changes in mammary and prostate tissue, suggesting a potential cancer risk. In some tests of female mice, exposure appeared to accelerate puberty.
A draft report from the National Toxicology Program, part of the Department of Health and Human Services, notes that there is no direct evidence that human exposure to BPA harms reproduction or infant development. “I don’t think there’s anything in this brief that should lead to alarm,” said Dr. Michael D. Shelby, director of the Center for the Evaluation of Risks to Human Reproduction, who oversaw the report. “It means we’ve got a limited amount of evidence from some studies that were done in laboratory animals.”
The main concern is the possible risk to infants and pregnant women, although Canada has begun a study to monitor BPA exposure among about 5,000 people to assess any danger to adults.
More here: http://www.nytimes.com/2008/04/22/health/22well.html?em&ex=1209096000&en=8a1d4bc01b9099f4&ei=5087%0A
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