A Hard Plastic Is Raising Hard Questions

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A Hard Plastic Is Raising Hard Questions By TARA PARKER-POPE

Are toxic plastics lurking in your kitchen? April 22, 2008

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. 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.

How much BPA are we exposed to?

BPA migrates into food from polycarbonate plastic bottles or the epoxy

resin coatings that line canned food. The typical adult ingests an

estimated 1 microgram of BPA for every kilogram (2.2 pounds) of body

weight. Babies who use polycarbonate bottles and formula from cans get

more, an estimated 10 micrograms per kilogram of body weight. A

microgram represents a trace amount. Consider this: a single M & M is

about a gram. If you cut it into 100,000 slices, one slice would equal

about 10 micrograms.

The 2003-4 National Health and Nutrition Examination Survey by the

Centers for Disease Control and Prevention found detectable levels of

BPA in 93 percent of urine samples collected from more than 2,500

adults and children over 6.

How do I know if the plastic containers in my home contain BPA?

Any product made of hard, clear plastic is probably made from

polycarbonate unless the manufacturer specifically states that it's

BPA-free. One way to check is to look for the triangle stamp on or

near the bottom: polycarbonate plastics should have the numeral 7 in

the triangle, sometimes with the letters PC.

Unfortunately, 7 is a catchall " other " category for a variety of

plastics. In my own kitchen, I found just one product with a 7 —

plastic fruit cups my daughter takes to school. But the plastic is

soft and pliable, so it is probably not made with BPA.

I also found refillable water bottles without a stamp. Because they

are hard, shatterproof and clear, it's reasonable to assume they are

made from polycarbonate.

What about canned food and drinks?

While much of the focus is on plastic bottles, most human exposure

occurs through the lining of canned foods. Canned beverages appear to

contain less of the chemical than canned foods like soup, pasta,

fruits and vegetables, which are often processed at high temperatures.

Virtually every canned product, even those labeled organic, has a

liner with BPA. One brand, Eden Organic Baked Beans, says it uses a

BPA-free can.

How do I lower my exposure?

Switch to frozen or fresh vegetables. Use glass, porcelain and

stainless-steel containers, particularly for hot foods and liquids. If

you don't want to use a glass baby bottle, several companies,

including the popular brand Born Free, now sell BPA-free baby bottles

and sippy cups. For formula-fed babies, you can switch to powdered

formula rather than liquid.

Although many plastic products claim to be microwave safe, some

scientists warn against putting any plastic in the microwave. " There

is such a wide variety now, from disposable containers to actual

Tupperware, " says Dr. Anila , a senior scientist for the

Environmental Working Group, a Washington-based advocacy group. " I

don't know of anyone who has done definitive testing of all these

different types of plastic containers to see what is leaching into food. "

http://www.nytimes.com/2008/04/22/health/22well.html