Canned foods sold in Canada contain the estrogen-mimicking chemical bisphenol A at concentrations as much as double the levels that prompted many consumers to shun plastic baby bottles and water bottles made from the controversial material, according to testing conducted for The Globe and Mail and CTV.
The highest amounts were in a food often consumed by children - tomato sauce, which had 18.2 parts per billion. But the news organizations tested 13 other canned goods purchased at Toronto stores, including beer, ravioli, apple juice and cream-style corn, and found bisphenol A in every sample.
Tomato juice had 14.1 ppb, chicken noodle soup as much as 9.9 ppb and ravioli 6.2 ppb.
It is the first time such a review of common, everyday food items has been done in Canada, and indicates there is widespread exposure to the chemical, also known as BPA, among those who eat canned goods, even if they do not use polycarbonate plastic bottles. 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.
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.
In April, Health Canada issued a draft risk assessment indicating that it planned to add bisphenol A to the country's list of toxic substances as a precautionary step, based on worries that the margin of safety for infants exposed to the chemical from plastic baby bottles and canned formula wasn't large enough.
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 agency is the first in the world to take precautionary action against low-level BPA exposures. It also said it intends to ban polycarbonate baby bottles and announced that it would work with infant formula makers to reduce the amounts leaching from their cans.
But Health Canada wasn't worried about older children and adults inadvertently consuming BPA from canned food, saying the risk was negligible. However, in anticipation that food makers may start reformulating the chemical out of their products, it also said it is "committed to working with the industry to investigate the safety of any possible replacement that industry may consider for bisphenol A-containing epoxy-based linings used in cans."
Many consumers are shunning polycarbonate plastic bottles because they're easy to identify, but it isn't generally known that bisphenol A "is kind of hidden" in cans, Mr. Smith said.
However, the industry insisted that there is no cause for concern. The amounts 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. One way to view cans is that they resemble a thin, plastic-like container on the inside, with a steel or aluminum shell on the outside for structural support.
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.
