Concern over canned foods
Our tests find a wide range of Bisphenol A in soups, juice, and more
The chemical Bisphenol A, which has been used for years in clear plastic bottles and food-can liners, has been restricted in Canada and some U.S. states and municipalities because of potential health effects. The Food and Drug Administration will soon decide what it considers a safe level of exposure to Bisphenol A (BPA), which some studies have linked to reproductive abnormalities and a heightened risk of breast and prostate cancers, diabetes, and heart disease.
Now Consumer Reports
' latest tests of canned foods, including soups, juice, tuna, and green beans, have found that almost all of the 19 name-brand foods we tested contain some BPA. The canned organic foods we tested did not always have lower BPA levels than nonorganic brands of similar foods analyzed. We even found the chemical in some products in cans that were labeled "BPA-free."
The debate revolves around just what is a safe level of the chemical to ingest and whether it should be in contact with food. Federal guidelines currently put the daily upper limit of safe exposure at 50 micrograms of BPA per kilogram of body weight. But that level is based on experiments done in the 1980s rather than hundreds of more recent animal and laboratory studies indicating serious health risks could result from much lower doses of BPA.
Deciding on a Safe Level
In the lab With the Food and Drug Administration poised to review rules on the plastic chemical Bisphenol A, we tested samples of a number of packaged foods to check levels of the compound and in some cases to see whether the type of packaging made a difference.
Several animal studies show adverse effects, such as abnormal reproductive development, at exposures of 2.4 micrograms of BPA per kilogram of body weight per day. Our food-safety scientists recommend limiting daily exposure to one-thousandth of that level, or 0.0024 micrograms per kilogram of body weight, following established practices to ensure an adequate margin of safety.
An FDA special scientific advisory panel reported in late 2008 that the agency's basis for setting safety standards to protect consumers was inadequate and should be re-evaluated. A congressional subcommittee determined in 2009 that the agency relied too heavily on studies sponsored by the American Plastics Council. BPA, a building block of plastics, is a component of epoxy resin used in cans and packaging. "The FDA's reliance on industry studies in determining BPA's safety must be re-evaluated in light of clear signs industry is willing to mislead the American people on this public-health issue
," said Rep. Bart Stupak, D-Mich., chairman of the House Energy and Commerce Committee's Oversight and Investigations Subcommittee. Bills are pending in Congress that would ban the use of BPA in all food and beverage containers.
Industry has been waging a fight against new regulations. The American Chemistry Council says on its Web site: "The weight of scientific evidence clearly supports the safety of BPA and provides strong reassurance that there is no basis for human health concerns from exposure to BPA." The chemical was first marketed in the 1940s as a plastic component and by the 1960s was used in almost all can linings to extend shelf life. Now it is one of the highest-volume chemicals in the world; at least 7 billion pounds are produced annually for use in countless products, including dental sealants, PVC water pipes, medical equipment, consumer electronics, and even cash-register receipts.
New evidence of the risks of BPA at low levels increases the concern about those multiple sources of exposure. "Our regulatory standards now are based on the outdated assumption that when you test a chemical's safety at high doses, the results also will reveal any risks occurring at low doses, but as hundreds of studies have now demonstrated, it doesn't work that way with estrogen-mimicking chemicals like BPA, which can have completely different and potentially more harmful effects at low doses," says Frederick vom Saal, a professor of developmental biology at the University of Missouri at Columbia and a leading researcher on BPA.
What We Found
We tested for BPA in soup, vegetables, tuna, and other canned products as well as noncanned versions from leading manufacturers such as Campbell's, Chef Boyardee, Del Monte, Nestlé, and Progresso, among others. Using outside laboratories, we tested three samples of each product, all bought in the New York metropolitan area or online. In all but one case, the three samples were of different lot numbers.
Our tests convey a snapshot of the marketplace and do not provide a general conclusion about the levels of BPA in any particular brand or type of product we tested. Levels in the same products purchased at different times or places or in other brands of similar foods might differ from our test results. Nevertheless, our findings are notable because they indicate the extent of potential exposure: Consumers eating just one serving of the canned vegetable soup we tested would get about double what the FDA now considers typical average dietary daily exposure.
We found that the average amounts of BPA in tested products varied widely; most items showed levels from trace amounts to about 32 parts per billion. Products in that range included canned corn, chili, tomato sauce, and corned beef.
The highest levels of BPA in our tests were found in the canned green beans and canned soup. In Progresso Vegetable Soup, the levels of BPA ranged from 67 to 134 ppb. In Campbell's Condensed Chicken Noodle Soup, the levels of BPA ranged from 54.5 to 102 ppb. Canned Del Monte Fresh Cut Green Beans Blue Lake had BPA levels ranging from 35.9 ppb to 191 ppb, the highest amount for a single sample in our test. Since we didn't test other canned green beans or soups, we don't know if this is typical of those products.
A 165-pound adult eating one serving of canned green beans from our sample, which averaged 123.5 ppb, could ingest about 0.2 micrograms of BPA per kilogram of body weight per day, about 80 times higher than our experts' recommended daily upper limit. And children eating multiple servings per day of canned foods with BPA levels comparable to the ones we found in some tested products could get a dose of BPA approaching levels that have caused adverse effects in several animal studies.
Given the significance of BPA exposure for infants and young children, we tested samples of Similac Advance Infant Formula and Nestlé Juicy Juice All Natural 100% Apple Juice. Samples of the Similac liquid concentrate in a can averaged 9 ppb of BPA, but there was no measurable level in the powdered version. Samples of the Nestlé Juicy Juice in a can averaged 9.7 ppb BPA, but there were no measurable levels in the samples of the same product packaged in juice boxes.
Although BPA levels in that canned juice were not among the highest in the foods we tested, canned juice can account for a substantial amount of dietary BPA exposure in children who drink a lot of it. Drinking three servings per day of canned apple juice with BPA levels comparable to the levels found in our samples could result in a dose of BPA that is more than our experts' daily upper limit.
Our tests of cans found that the majority were lined with an epoxy-based material, which is normally made with BPA. But a handful had a nonepoxy-based liner. Those findings along with the BPA results suggest that bypassing metal cans in favor of other packaging such as plastic containers or bags might lower but not eliminate exposure to BPA in those foods, although this wasn't true for all of the products we tested.
For instance, Campbell's Chicken Noodle Soup in plastic packaging contained detectable amounts of BPA but at levels that were significantly lower than the same brand of soup in the can. The StarKist Chunk Light canned tuna we tested averaged 3 ppb of BPA, but BPA levels in the same brand in a plastic pouch weren't measurable. We tested Bird's Eye Steam Fresh Cut Green Beans, frozen in a plastic bag, analyzing three samples as packaged and another three samples after microwaving in the bag. We found all contained very low levels of BPA, about 1 ppb or less.
The samples of Chef Boyardee Beef Ravioli in Tomato and Meat Sauce packaged in a plastic container with a metal peel-off lid had BPA levels 1.5 times higher than the same brand of food in metal cans. Our test of the metal peel-back lid revealed that the inner coating is epoxy-based.
We tested two products that their manufacturers claimed were packaged in BPA-free cans and found the chemical in both of the foods. Although tests of the inside of the cans found that the liners were not epoxy-based, Vital Choice's tuna in "BPA-free" cans was found to contain an average of 20 ppb of BPA and Eden Baked Beans averaged 1 ppb.
What Should Be Done
Consumers Union, the nonprofit publisher of Consumer Reports
, believes manufacturers and government agencies should act to eliminate the use of BPA in all materials that come into contact with food.
In Japan, most major manufacturers voluntarily changed their can linings in 1997 to cut or eliminate the use of BPA because of concerns about health effects. A 2003 Japanese study found that the levels of the chemical in subjects' urine dropped by 50 percent after the change in cans was made.
Pete Myers, chief scientist at Environmental Health Sciences, a nonprofit group based in Charlottesville, Va., says that while can linings aren't the only source of BPA exposure, the experiences in Japan can be instructive.
The full article will appear in the December issue.