Food Protection Connection: Safety Concerns - BPA in Canned Foods

(reprinted from Dietary Manager, February 2010)

As explained in Food Protection Connection – Nov/Dec 2008, BPA is a chemical used in manufacturing food containers, namely plastics with the recycled “#7” designation, as well as linings of some food cans, soft drink cans, and other packages, and in baby bottles and sippy cups. BPA forms part of a resin that lines containers. Because it is a food-contact substance, small amounts can enter food, and scientists have looked closely at its safety.

Test Results

Consumer Reports tested 19 brand-name canned foods including soups, juice, tuna, green beans, and infant formula, for BPA. While levels varied widely, Consumer Reports noted that most products contain BPA, with small amounts showing up even in some products marked “BPA­free”. Highest levels showed up in canned green beans and canned soup. For example:

• Progresso vegetable soup had 67 to 134 parts per billion
• Campbell’s condensed chicken soup had 54.5 to 102 parts per billion
• Two brands of cut green beans ranged from 35.9 to 191 parts per billion.

Food in cans with pull-off tops ranked higher for BPA, compared with ordinary metal cans, presumably because the lids are lined with a resin that contains BPA. Also, identical products packaged differently tested much differently as well, according to Consumer Reports. For example, a StarKist Chunk Light canned tuna in a plastic pouch did not register BPA, but the same product in a can showed 3 parts per billion of BPA.

A Similac concentrated infant formula came in at 9 parts per billion of BPA, with no reading for the powdered alternative. A canned nestle Juicy Juice apple juice came in at 9.7 parts per billion, but the same product in juice boxes contained no measurable levels, according to Consumer Reports.

What Do the Numbers Mean?

How much BPA is safe? This is not an easy question, as scientists are unsure. The Environmental Protection Agency (EPA) has set a safe daily intake of 50 micrograms per kilogram of body weight per day. Translating the numbers, Consumer Reports explains that if an adult weighing 165 pounds ingests 123.5 parts per billion of BPA (from a serving of canned green beans), he is taking in 0.2 micrograms per kilogram of body weight. This is far below the EPA safe intake. However, due to demonstrated ill effects in animal studies, Consumer Reports scientists suggest this safety limit is set 1,000 times too high. By this unofficial standard, the man eating a serving of green beans is consuming BPA at a level that is 80 times higher than a “safe” level.

How does Consumer Reports justify its advice? it cites an FDA study from 2008 indicating it’s time to re-evaluate safety standards for BPA. it also cites a 2009 Congressional subcommittee that concludes that government leans too heavily on research from the plastics industry. At this time, says Consumer Reports, “Bills are pending in Congress that would ban the use of BPA in all food and beverage containers.”

What are the Risks?

Research confirms that due to a broad-based presence in our food supply, BPA appears in about 93 percent of the US population. Studies suggest the chemical could raise risks for diabetes, heart disease, high liver enzyme levels, infertility, breast cancer, and prostate cancer. Among children, exposure may also lead to early puberty. BPA may also affect the nervous system in children, with possible effects such as hyperactivity or learning disorders. Its effects stem from its chemical function, which mimics the hormone estrogen.

Of greater concern is potential effects on infants and children under age six, whose bodies do not eliminate BPA as effectively as adults’. This group is “most susceptible” to the effects of BPA, according to the national Toxicology Program (nTP). nTP is an arm of the national institutes of Health. An nTP report issued in September 2008 noted, “The nTP has some concern for effects on the brain, behavior, and prostate gland in fetuses, infants, and children at current human exposures to bisphenol A.” At the same time, the nTP concluded there is “negligible concern” for adults.

Regulatory & Industry Responses

In its current consumer message on BPA (8/31/08), the FDA states, “Based on our ongoing review, we believe there is a large body of evidence that indicates that FDA-regulated products containing BPA currently on the market are safe and that exposure levels to BPA from food contact materials, including for infants and children, are below those that may cause health effects. However, we will continue to consider new research and information as they become available.” FDA Commissioner Dr. Margaret A. Hamburg stated in 2009 that the FDA is further evaluating safety.

In 1997, Japanese food packaging companies vastly reduced use of BPA due to health concerns. In 2008, health officials in Canada banned use of BPA in baby bottles. In March 2009, the six largest US manufacturers of baby bottles announced that they would discontinue use of BPA in baby bottles (Washington Post, March 6, 2009). Michigan-based Eden Foods began using BPA-free cans in 1999, replacing BPA with oleoresin. The company explains, “Oleoresin is a non-toxic mixture of an oil and a resin extracted from various plants, such as pine or balsam fir. These cans cost 14% more than the industry standard cans that do contain BPA.” (www.edenfoods.com)

Best Practices

While the jury is still out on defining safe intakes of BPA, consumers and foodservice managers can implement several best practices to reduce potential risk, as suggested by the nTP and Consumer Reports. Among them:

• Reduce use of canned foods, selecting can-free packaging when practical.
• Avoid using plastic (polycarbonate) containers marked with a “#7”.
• Use glass containers rather than plastic when microwaving foods, as higher levels of BPA are released by polycarbonate packages in the microwave.

by Sue Grossbauer, RD
Sue Grossbauer, RD, is president of The Grossbauer Group and the author of many ANFP publications and online courses. She supports foodservice organizations in areas relating to marketing, education, food safety, and technology.