Your BPA questions, answered

When we posted a little analysis of the new research on the toxic plastics chemical bisphenol A (BPA) leaching from polycarbonate bottles, we had no idea how many questions it would inspire. This month, instead of the usual Ask EWG feature, we've put together a post in which we answer as many of your BPA questions as we can. We know you've probably got even more questions. Ask away and we'll do our best to answer, but keep in mind that there are some questions we just don't have the answers to yet.



First, a little review: What is BPA?

BPA is a chemical used in the production of certain kinds of plastics, including polycarbonate plastic (like hard, colored water bottles and 5-gallon drinking water coolers) and the lining of most food and beverage cans. BPA can leach from the plastic and into foods and beverages, especially when it's heated or used for long periods of time. The U.S. Centers for Disease Control found BPA in the bodies of 93 percent of the people they tested, which is especially troubling since the chemical is linked to breast and prostate cancer and neurobehavioral changes in offspring exposed in the womb. It's a good idea to avoid exposure to BPA whenever possible.



Stuff you drink out of



Polycarbonate bottles: As the original post mentioned, studies show low levels of BPA leach out of polycarbonate bottles (like Nalgene and other hard, colored water bottles) at room temperature. More BPA leaches when the bottles are filled with hot liquid. Generally these bottles will be marked with recycling number seven. Polycarbonate is hard, translucent or clear plastic.These bottles may be marked with the number 7. If you're going to use a polycarbonate bottle, be aware that it's likely that higher amounts of BPA leach out of older and damaged bottles. Although we recommend that you avoid drinking from polycarbonate bottles, it's important to note that your potential exposure to BPA through canned food is considerably higher.



One commenter mentioned recycling; as far as we know, #7 drink bottles are rarely recyclable. To be sure, check with your local recycling center.



Other plastic bottles: Don't reuse single-use plastic drink bottles (PET, or #1 plastic). It's a good instinct, but bacteria can build up on the inside, and they may leach chemicals too. Drop them in the recycling instead. Bottles made from flexible, cloudy-colored HDPE #2 are considered a safer option if you must have a plastic bottle.



Water filter pitchers and containers: These hard, clear plastic containers may or may not be made of polycarbonate. One commenter left a link to a Q&A on The Green Guide which reveals that Brita filter systems use containers made from styrene methylmethacrylate copolymer. Brita confirmed for us that they don't use (and never have used) polycarbonate plastics. Other filter brands may use polycarbonate plastics; check with them to find out. If your filter does use polycarbonate plastic, you could consider filtering water and storing it in glass bottles.



Camelbak hydration systems: Camelbaks's inner bladder is made from flexible polyurethane, which contains no BPA or phthalates. They have an antimicrobial silver lining. There's no risk of BPA exposure, but some scientists have raised concerns about antimicrobial silver.



Metal water bottles: Metal water bottles come in two variations: stainless steel and aluminum. Many aluminum bottles are lined with an epoxy or enamel, which is likely to contain BPA. Sigg, the Swiss company that produces a line of aluminum water bottles, recently produced test data showing that several new and used Sigg bottles did not leach BPA at levels greater than 2 ppb after three days of heating in nearly boiling water -- that's less leaching than polycarbonate bottles under the same condition. Stainless steel bottles, like Klean Kanteen, are not lined, so there's no risk of BPA exposure there.



Food containers



Canned Foods: No matter what brand you use or where you buy your canned food, the cans are almost certainly lined with an epoxy resin that contains BPA. If they didn't use it, the cans might rust, or you might end up with metal residues in your food. But because of the high temperatures used in the canning process, your potential exposure to BPA from canned food is much higher than your potential exposure from plastic water bottles.



Only one manufacturer that we know of uses non-BPA lining on some of their food cans:



Eden Organic Beans are packed in lead free tin covered steel cans coated with a baked on oleoresinous c-enamel lining that does not contain bisphenol A (BPA). (Oleoresin is a natural mixture of an oil and a resin extracted from various plants, such as pine or balsam fir). These cans cost 13.77 percent more than the industry standard cans that do contain BPA. This costs Eden $300,000 more a year. To our knowledge Eden is the only U.S. company that uses this custom made BPA-free can.





Eden's tomato products are still packaged in cans with a BPA-based lining. Have a look at EWG's report for lots more on BPA in canned foods, including certain canned pastas and soups that contained the most BPA.



Reusable food containers: According to Kathleen's comment, Tupperware has confirmed that their Rock'n'Serve line does contain BPA. Other reusable containers may be made of polycarbonate. If not marked with a number 7, these would be very rigid clear or translucent plastic (not cloudy or flexible like yogurt containers). As an extra precaution, avoid putting hot liquids in these or microwaving them. In general it's best to use safe ceramics or glass containers for microwaving whenever possible.



Plastic wrap: In 1998, it was revealed that some plastic wraps contained chemical plasticizers called phthalates, which can migrate into food. In 2006, the industry group American Chemistry Council reported that phthalates are no longer used in any US plastic wraps. Most plastic wraps are made of LDPE, which has fewer contaminant concerns. Companies aren't required to list what's in their plastic wrap, though, so your best bet is to be cautious: Avoid microwaving plastic wrap (use a paper towel instead), and if you must, make sure it's a microwaveable version. That much, at least, will be listed on the box.



More consumer goods



Products for baby: A few of you expressed concerns about products designed for babies, from bottles to formula to pacifiers. Luckily, we lay out the best choices for many baby products in our guide to baby-safe bottles and feeding. Some basics: Choose bottles made from glass or BPA-free plastic. Use a clear silicone nipple, and if you're feeding formula use a powdered version mixed with unfluoridated water. As for pacifiers, while the hard plastic part may be made of polycarbonate plastic, that part doesn't go in baby's mouth -- so get a version with a silicone nipple, and don't worry too much about the rest.



Dental fillings, dental sealants: These can be BPA-based. If you're concerned, ask your dentist to show you the Material Safety Data Sheets (MSDS) for the filling materials and look for bisphenol A or bisphenol A diglycidyl ether (BADGE), and bisphenol A-dimethyl acrylate (Bis-DMA). A fourth chemical, bis-glycidyldimethacrylate (Bis-GMA), does not appear to give off BPA during use. Try to avoid having dental work done while pregnant or breastfeeding. Remember that BPA passes through your body quickly.



Mouthguards: One commenter asked if mouthguards made out of polycarbonate plastic would be a concern. Contact the manufacturer directly for more information about the type of plastic your mouthguard is made of. If it is polycarbonate, then there is some potential for BPA leaching.



The science



European safety assessment of BPA: One commenter questioned the validity of the study mentioned in the post, based on a comparison with the European Union's assessment. We'd like to caution against holding the EU up as the paragon of chemical safety; while it's true that they're sometimes more cautious about chemicals than the US, that frankly isn't saying much. In this case, the EU assessment ignored the results of dozens of studies showing very low dose effects of BPA and assumed that rodents are far more sensitive than humans to this chemical--an assumption that is by no means universally endorsed.



Here in the U.S., the National Institute of Health (NIH) is currently trying to reconcile the results of 2 expert panels that came to very different conclusions about the potential harm of low dose BPA exposures. There results are expected some time in 2008.



Is BPA making me sick? Can I be tested? BPA passes very quickly through the body, so testing yourself would only give you a snapshot of the past couple of hours. In general, laboratories do not conduct BPA testing for individuals, and people must be part of a scientific study to be tested. Your best bet is to do what you can to limit your exposure to BPA, and support efforts to require that industrial chemicals are fully tested for safety before they are put in our food and in our homes.



By EWG

March 13, 2008

http://www.enviroblog.org/2008/03/your-bpa-questions-answered.html