Behind the Brand Curtain
BPA in Canned Food: The canned food landscape
The global canned food market was worth more than $77 billion in 2013 and is expected to reach nearly $100 billion by 2020 (Research and Markets 2013). Anchoring that growth are canned foods’ convenience, affordability and shelf-stability. Canned food can be a good source of nutrients, especially for people on tight budgets or with limited access to fresh foods. In fact, canned food is a routine part of many diets, contributing as much as 17 percent of daily nutrients for some people (FDA 2008).
Can linings, in use since the 1950s, are necessary to prevent or slow the interaction of a food with a can’s metal. Epoxy resin, made from polymers containing BPA, has been favored for can coatings because it protects against metal corrosion and holds up to the heat extremes of sterilization.
Over the last 20 years, however, a steady stream of scientific studies have documented the human health hazards of BPA, including its links to an array of illnesses and its tendency to migrate from food packaging into food.
The North American Metal Packaging Alliance, a trade group representing the metal food packaging industry, estimates that 75 percent of canned foods sold in the U.S. are lined with a BPA-based polymer (Rost in Main 2015). Residual or unreacted BPA leaches from the can into food. In 2007, EWG tested nearly 100 canned foods and baby formula and detected BPA in more than half of the samples. BPA concentrations ranged from 2 to 385 parts per billion in food (EWG 2007).
These results were confirmed and extended by testing performed by the Canadian government, the federal Food and Drug Administration, academic researchers and non-profit groups (Bemrah 2014, Cao 2008, Cao 2010, Consumer Reports 2009a, FAO/WHO 2011, Kannan and Liao 2013, National Workgroup for Safe Markets 2010, Noonan 2011, UKFSA 2001).
Nearly all Americans have measureable concentrations of BPA in their bodies; canned food is presumed to be a major source of their exposures. Harvard students who volunteered to eat canned soup daily showed a 10-fold increase in BPA concentrations in their urine compared to days that they ate fresh soup (Carwile 2011). Another study found an average 4.5 point increase in blood pressure among study participants on days they drank two servings of a beverage packaged in a BPA-based metal can as opposed to days they drank the same beverage from a glass container (BAE 2015).