RODALE NEWS, EMMAUS, PA—The next "BPA-free product" that still contains BPA? Your Sigg water bottles. The popular Swiss manufacturer of decorative water bottles sold at Whole Foods, Target, and outdoor retailers admitted last week that despite some previous, misleading statements, they had been using the hormone-disrupting chemical bisphenol A (BPA), which has been linked to a wide array of chronic illnesses including obesity and cancer.
THE DETAILS: Aluminum water bottles need to be lined to prevent juices or other acidic drinks from reacting with the metal, which will cause the contents to taste metallic. Nearly all canned foods, soda cans, and baby formula—anything packaged in metal—are lined with an epoxy resin, of which BPA is a building block.
For years, Sigg had told its customers that they used a "water-based epoxy resin" in their aluminum water bottles, and that the resin leached no BPA. But they wouldn't disclose the exact contents of the liner, claiming it was a proprietary formula. The company had the bottles independently tested for levels of BPA and published the results of those tests online, which intentionally or not lead its customers to believe that there was no BPA in its proprietary liners. Last week, however, the company published a somewhat confusing letter on its website, stating that all Sigg water bottles are "now BPA-free." According to the letter, the company had actually been using a liner "that contained trace amounts of BPA" until August 2008, when they switched to a new plastic resin—also proprietary in makeup—that contains absolutely no BPA. In the letter, the company's CEO Steve Wasik writes, "Last year, the primary concern was that of BPA leaching from bottles. Since that time the dialogue has evolved such that now some people are concerned about the mere presence of BPA, and some states are considering legislation."
WHAT IT MEANS: It's all about semantics. Claiming that a product doesn't "leach" BPA is different from saying the product doesn't actually contain it. "People are right to say, huh?," says Sonya Lunder, MPH, senior analyst in the research division of the Environmental Working Group, a consumer-advocacy group that has tested various metal food containers and at one point raised questions about the epoxy liner used in Sigg aluminum water bottles. "We knew from existing scientific data that anytime you have an epoxy resin, you have BPA as a building block of the material," she says, adding that the company specifically targeted consumers who were switching to aluminum water bottles because they didn't want to be exposed to questionable chemicals in plastics. "It certainly makes me question more when a company claims that their mix is proprietary," she says. "What's the replacement? Has it been tested?"
For its part, Sigg is accepting returns of the old bottles with the BPA liner, and if you'd like more information on how to do that, you can email them at info@mysigg.com.
Want to avoid BPA entirely? Here are a few ways to protect yourself:
• Stick with stainless steel. Stainless steel bottles don't require epoxy liners, since they don't react with acidic drinks. Lunder advises avoiding generic aluminum water bottles because they contain epoxy liners that Sigg's tests found leached much higher amounts of the chemical than Sigg's did.
• Know your major exposures. Despite all the attention paid to polycarbonate plastic (also made with BPA) water and baby bottles, our primary dietary exposures still come from canned foods and baby formula, says Lunder. "Aluminum is a hidden issue because no one realizes that it has a liner," she says.
• Avoid canned sodas. There are lots of reasons to avoid canned soda, not the least of which being that they contain more added sugar than most people should have in a single day. But soda cans are also lined with the same epoxy resin. "Soda was on low end of the spectrum," says Lunder, regarding BPA concentrations. But many of us drink more soda in one day than we eat canned food.
• Be aware it builds up. Recent studies have found that our bodies aren't eliminating BPA as rapidly as scientists thought we could, and that the chemical could build up in body fat. BPA is so ubiquitous that it crops up in hidden sources like recycled-paper coffee cups and credit card receipts, so it's important to limit the exposures you're aware of as much as possible.