Most consumers purchase a combination of fresh, frozen, and canned food to prepare meals, and with the holiday season fast approaching, the purchase of convenience foods is higher than usual. Canned food is affordable and makes cooking quick and convenient. Low-income communities depend on canned food as a staple to their pantry because they often live in “food deserts” and lack access to diverse and fresh food choices. What do we know about food cans and their impact on our health and the environment? With “BPA-free” labels on many cans now, there’s more attention to the thin interior lining of canned food that preserves contents, prevents metal corrosion from the inside out, and prolongs shelf life. What is this lining made of and is it safe?
The Lining of Food Cans and BPA
Before 2019, the lining of food cans usually consisted of bisphenol A, or BPA, an epoxy resin that enables plastic to be malleable yet strong. BPA is also found in receipt paper, water bottles, in the lids of foods and beverages packaged in glass jars and bottles, aerosol cans for whipped toppings and nonstick sprays, tins of cooking oil, and aluminum beverage cans.
The problem with BPA being in canned food linings it that it can migrate into the food contents, especially when heated such as during pasteurization, or when the food is acidic such as tomato products. In the mid-1990s, scientists learned that BPA was an endocrine disrupting chemical that looks and acts like hormones in the body but confuses the endocrine system and cause reproductive problems, cancers, metabolic disorders, and developmental issues, especially for pregnant women and children.
As a result, between 2017 and 2019, manufacturers dramatically started phasing out BPA linings in canned food. By 2019, studies by the Center for Environmental Health showed that 95% of cans tested free of BPA, and the Can Manufacturer’s Institute reported that 95% of U.S. food can production were using alternative liners. In California, the Proposition 65 warning label or shelf sign will indicate the possible presence of BPA at concentrations above a “safe harbor level,” and we now see canned food with “BPA-free” labels, but only a handful of companies specify which BPA-free liner they are using instead. So, you can rejoice if you see a can with a BPA-free label on it, but you probably won’t know what alternative is being used.
Are BPA-free Alternatives Safer?
Ironically, back in 2016, a consortium of nonprofit groups had already issued the report Buyer Beware: Toxic BPA and regrettable substitutes in the linings of canned food, which noted that many of the new linings being developed were not great alternatives. Only a handful of national brands and retailers like Annie’s Kitchen and Amy’s Organics currently disclose what linings replaced BPA linings, and these include alternatives like polyester, acrylic, non-BPA epoxies, polyvinyl chloride (PVC) copolymers, or olefin polymers. Some vinyl may be more benign than BPA but it can still leech into food and have biodegradability and environmental toxicity concerns. Polyesters are toxic to aquatic life and persist in the environment for years. For example, PVC, which is well known for plumbing pipes, window frames, flooring, and roofing materials, is derived from vinyl chloride, a known human carcinogen that causes cancer, immune system damage, and hormone disruption. PVC is also not good for the environment; from cradle to grave, the PVC lifecycle (production, use, and disposal) results in the release of toxins that build up in water, air, and food chains.
While lined cans are still recyclable, decomposing plastic linings lead to the formation of microplastics that accumulate in the environment, contaminate soil and water, and become part of the food chain, thereby affecting earth’s ecosystem. Eden seems to be the only brand of canned food in the U.S. that uses non-plastic liners. Eden uses an oleoresin c-enamel, which is a mixture of oil and plant resin extracted from pine or balsam fir trees.
The Bottom Line on BPA in Canned Food
Canned foods are largely safe from BPA now, thanks to consumers, scientists, and health advocates, but most canning companies are not providing full transparency on whether they are using BPA-free cans or alternatives that are safe for public health and the planet.To avoid questionable BPA-free alternatives altogether, consumers can opt for buying fresh produce or frozen produce, which is packaged in generally safer plastics; buy food in glass jars; shop bulk and dry goods bins and prepare staples like beans from scratch; and, of course, write to companies directly and ask what linings they use in their canned food products and request safety data.
Sources and Further Reading:
Photo by Donna Spearman on Unsplash
https://pmc.ncbi.nlm.nih.gov/articles/PMC10779931/
https://ceh.org/yourhealth/is-canned-food-safe-from-bpa-now/
https://www.ewg.org/news-insights/news/bpa-update-tracking-canned-food-phaseout
https://www.greenscreenchemicals.org/images/ee_images/uploads/resources/CANSwebinar.pdf
https://www.edenfoods.com/articles/view.php?articles_id=178
Replies