BPA Found in Canned FoodsJun 2, 2008 | Parker Waichman LLP
According to recent testing, canned foods sold in Canada have been found to contain BPA concentrations as high as double the levels that prompted many to stop using BPA-laced plastic baby and water bottles. Less than half a cup of tomato sauce or a cup of chicken noodle soup would exceed the lowest dose found in recent research to have an adverse effect on animals.
Bisphenol-A—or BPA—is a fairly ubiquitous chemical that mimics the hormone, estrogen, and is used in polycarbonate plastic products, including baby bottles and metal can coatings and could be linked to a range of hormonal problems. In the lab, BPA is linked to sex-hormone-imbalances, including breast and prostate cancer, early puberty, miscarriage, low sperm count, and immune-system changes.
The study found the highest BPA amounts were in tomato sauce, which had 18.2 parts per billion (ppb). Testing on 13 other canned goods purchased at Toronto stores, including beer, ravioli, apple juice, and cream-style corn, found BPA in every sample; tomato juice had 14.1 ppb; chicken noodle soup, 9.9 ppb; and ravioli, 6.2 ppb. "These results provide further evidence that Canadians are marinating in this chemical on a daily basis," said Rick Smith, executive director of Environmental Defence, a Toronto advocacy group lobbying Health Canada to ban BPA from food and beverage containers. Many consumers have stopped using polycarbonate plastic bottles because they're easy to identify, but it isn't generally known that BPA "is kind of hidden" in cans, Smith added.
In April, Health Canada issued a draft risk assessment indicating it planned to add BPA to the country's list of toxic substances. Health Canada tested 21 cans of liquid infant formula and found BPA in every sample, with levels ranging from 2.3 ppb to 10.2 ppb. The agency is the first in the world to take precautionary action against low-level BPA exposures, said it plans to ban polycarbonate baby bottles, and announced it would work with infant formula makers to reduce the amounts leaching from their cans.
Cans contain BPA because the chemical is used to make the resin that lines the insides, creating a thin, plastic-like container on the inside, with a steel or aluminum shell on the outside for support. Trace amounts of BPA leach from cans for the same reason they seep from heated baby bottles: High temperatures used during canning that destroy microbes that cause food poisoning cause BPA to escape from the resin. This also occurs with some acidic foods. Most cans are cooked at microbe-killing temperatures above 100 degrees after their food or beverage contents are added, although lower temperatures around 60 degrees are used on beverages sterilized through pasteurization.
According to a recent government report developed by a group of scientists from the Centers for Disease Control (CDC), the Food and Drug Administration (FDA), and the Institutes of Health (NIH), very low doses of BPA cause profound effects on laboratory animals, particularly during pregnancy and infancy and BPA can permanently rewire genetic programming before birth. The federal National Toxicology Program said experiments on rats found precancerous tumors, urinary tract problems, and early puberty when animals were fed or injected with low doses of BPA.