On your next trip to the grocery store, think twice before stocking up on canned goods and gallons of water.
One chemical under scrutiny by Health Canada is bisphenol-A (BPA), a substance used to make polycarbonate plastics -- tough, high-performance plastic material found in the lining of tin cans and used to create reusable, high-performance plastic containers.
It's in our food
According to Sarah Winterton, program director of Environmental Defence, BPA is detected in people who have ingested the chemical through food or liquids stored in plastic containers or plastic-lined cans. "Food is a big marker for bisphenol-A because it slowly leaches out from containers," she says.
Ingesting BPA is a concern because this chemical is classified as an endocrine disruptor -- a substance that interferes with the body's natural hormone system. BPA has estrogenic properties and will bind to the body's estrogen receptors. In short, our bodies think this chemical is the natural hormone and will use it to regulate our entire endocrine system. According to the World Health Organization, endocrine disruptors are linked to decreased sperm quality, early puberty, neurobehavioural problems and cancer.
Exposure is low
Thus said, the amount of BPA we ingest through our food containers is very low. Dr. David Miller, toxicologist and professor of biochemistry at Carleton University, says BPA has been tested extensively for safety and the amount we ingest is well below the safety minimum. "People have been worried about things that bind to estrogen receptors for a long time," he says. "Because of this concern, large testing has gone on in the European Union, the United States, Canada and Japan to get to the bottom of this, to make sure we're not making a big mistake."
He says these different committees from different countries have all come to the same conclusion: that BPA is nothing to worry about when used under conditions of normal use. "To get any effects [from BPA] you would have to melt your bottles down and spoon the stuff in," he says.
However, as of April 2008, Health Canada has announced a reassessment of BPA and is making moves to limit Canadians' exposure to the chemical.
Page 1 of 2 — on page 2, find tips to reduce your plastic use.
One study conducted by Dr. Frederick Vom Saal from the University of Missouri suggests low levels of BPA are just as dangerous as high levels, but Dr. Miller says no one has been able to repeat Dr. Vom Saal's findings since the 1998 experiments.
But Winterton feels any exposure to BPA is still unhealthy. "Something taking the place of hormones is a wrong thing," she says, adding that rapid cell growth occurs in utero and during puberty, which are key times of vulnerability to endocrine-disrupting substances.
Reduce the risk
Reducing exposure to plastics is the best way to keep exposure to BPA and other plastics chemicals to a bare minimum. However, it is nearly impossible to avoid plastic altogether.
The easiest way to identify plastics containing BPA is to look for the recycling symbol #7 -- generally hard, durable plastic products you can see through. Examples include some Tupperware containers, Nalgene bottles, and some baby bottles. The newer the product the more stable and safe it is, but over time and especially after heating, the polymers break down and allow BPA and other chemicals to migrate into foods.
Winterton recommends using safer plastic products with recycling symbols (or "PETE" numbers) 1, 2, 4 and 5.
Commercial water bottles, for example, have a recycling symbol 1. Gladware is a 5. Although these are safer, the bottles are not designed for re-use nor should the Gladware be heated.
(Click here for a complete definition of plastic identification codes and related products from the American Plastics Council.)
The following are some easy tips to make your food as plastic-free as possible:
• Buy fresh or dried fruits and vegetables and store them in cloth or glass containers. Winterton says most health food stores have special cloth bags for saving salad greens.
• Bring a large glass to work and refill it with water instead of using a plastic Nalgene bottle.
• Eat less canned food from plastic-lined cans, soaking lentils or beans overnight. "I do it and it's really no effort -- you just have to remember," says Winterton.
• Wrap sandwiches in wax paper instead of plastic baggies.
• If you're transporting food in reusable containers, bring a dish to heat it up.
• Further reduce your use of canned goods by making your own sauces, preserves and jams. Follow these links to easy Canadian Living recipes for great food kept delicious in jars.
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