ShareThisCanned foods sold in Canada contain twice as much of an estrogen-mimicking chemical as plastic baby bottles and water bottles -- which have been shunned because of health concerns -- according to testing conducted for The Globe and Mail and Canadian Television.
The first time everyday foods has been reviewed in Canada, the testing indicates there is widespread exposure to the chemical, also known as BPA, among those who eat canned goods.
None of the levels exceed current Health Canada guidelines, industry officials point out.
"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 that has been lobbying Health Canada to ban bisphenol A from food and beverage containers.
The highest amount of bisphenol A was found in a children's favorite, tomato sauce, which had 18.2 parts per billion.
The news organizations tested 13 other canned goods purchased at Toronto stores, including beer, ravioli, apple juice and cream-style corn. Bisphenol A was found in every sample.
Tomato juice had 14.1 ppb, chicken noodle soup as much as 9.9 ppb and ravioli 6.2 ppb.
Based on the results of animal experiments, researchers have linked low amounts of BPA to effects such as breast cancer and the earlier onset of puberty in girls, among other conditions, with exposures during fetal development and in early life the most damaging.
Health Canada tested 21 cans of liquid infant formula, and like the Globe/CTV survey, found BPA in every sample, with levels ranging from 2.3 ppb to 10.2 ppb.
The amounts of chemical leaching "are well below any regulatory limit" and have been "deemed to be safe by numerous expert panels," said John Rost, chairman of the Washington-based North American Metal Packaging Alliance, a trade group. He dismissed concerns about bisphenol A leakage as an "unsubstantiated fear."
Cans contain BPA because the chemical is used to make the resin that lines their insides.
Trace amounts of bisphenol A are leaching from them for the same reason they have been found to seep from heated baby bottles: The high temperatures used during the canning process to destroy microbes that cause food poisoning also prompt the chemical to migrate out of its resin. The acidic nature of many foods causes some to leak out as well.
The health risks from the levels found in the Globe/CTV testing are subject to a major dispute among some researchers.
Based on Health Canada's current exposure guideline, which was developed in 1995 before it was widely known that BPA could act like a female hormone at very small doses, an adult would need to consume hundreds of cups of the tested products each day to exceed the limit.
But 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. That was a 2005 experiment at Tufts University School of Medicine in Boston on mice exposed to amounts far below those detected in the Globe/CTV testing.
One of the scientists on the mouse experiment, Ana M. Soto, professor at Tufts University School of Medicine, said she believes that very small doses of BPA constitute a risk, and consequently avoids canned foods.
"If people stopped eating canned food, nothing bad will happen to them," Soto said.
Soto also said the safe exposure to BPA is not known among scientists studying the chemical's effects at low exposures.
"It is very difficult to determine what is safe," she said. "The government cannot say that they know that there is a dose that is safe. They cannot say that today because we do not know that as scientists, so they don't know that either."
(Distributed by Scripps Howard News Service, www.scrippsnews.com.)
