By Laurine Brown, PhD, MPH, RD
If you’re like most Americans you’ve likely got some bisphenol A (BPA) cluttering your body. Given our intimate relationship with this tongue-twisting substance, we ought to understand more about its origins and fate, especially since a growing body of evidence is linking it to serious health risks. What do we know?
BPA is an industrial chemical used primarily in hard plastics (like polycarbonate) and epoxy resins. Used since the 1960s, it enhances many common consumer products like baby bottles, microwaveable plastic containers, metal food and beverage can liners, impact resistant safety equipment and medical devices, dental sealants, and even cash register receipts.
A stunning 93 percent of Americans recently sampled by the Centers for Disease Control (CDC) were found to have detectable levels of BPA in their urine. It’s even been measured in amniotic fluid and blood of unborn babies and in newborns. This shouldn’t surprise us because we make a lot of this chemical — an estimated 8 million pounds a year — earning its rank among the 2,000 chemicals that we produce in the highest quantities.
Such universal exposures concern many scientists in light of mounting evidence of harm to human health. BPA is a man-made chemical that is thought to mimic the hormone estrogen. Over 100 peer-reviewed studies have found disturbing evidence of health problems even at low doses and common exposure levels — breast and prostate cancer, heart disease, diabetes, obesity, miscarriages, reproductive problems, neurological and behavioral problems. BPA may cause “epigenetic” changes, meaning it alters the way genes switch on and off, and genetics that can be passed on to the next generation.
While the science leaves us with unanswered questions, reducing exposures seems prudent. Extrapolating from European studies, canned food is thought to be the main source of exposure for adults and teenagers, and polycarbonate baby bottles for infants. Groups like Consumers Union, the nonprofit group of Consumer Reports, believe manufacturers and government agencies should eliminate use of BPA in food containers. Interestingly, Japanese manufacturers voluntarily changed their can linings in 1997 due to health concerns, and a 2003 follow-up study found that urine levels of BPA dropped 50 percent. While US policy makers debate options, taking a few simple precautions may help reduce your individual exposures.
What Can You Do?
- Eat fewer canned foods and drinks. Many can linings are coated with a protective epoxy resin, and BPA can leach into the food, especially with acidic foods, like tomatoes. Choose fresh or frozen fruits and vegetables (other perks – more nutrients, less preservatives, and taste better). Cook legumes from scratch (other perks are less sodium and cheaper). Canned soft drinks generally have lower levels than canned foods, but significant levels have still been detected, so choose drinks in glass bottles instead of cans (alternatively, individual plastic beverage bottles like water or soda usually do not contain BPA).
- Avoid polycarbonate plastics (may have #7 recycling code on the bottom) when possible. If you do use them, don’t heat them up. Hand-wash them, since repeated use of dishwashers and harsh detergents can cause them to deteriorate and leach more chemicals like BPA. Scratched containers (like Nalgene or baby bottles) have also been found to leach more, so discard these. Choose stainless steel re-usable water bottles or travel mugs (check to be sure they don’t have a plastic liner inside.)
- Don’t heat up plastics. Heating plastics (microwaving or putting hot beverages or food in plastic) speeds leaching of chemicals, like BPA, out of containers into the food or liquid. Interestingly many “microwavable” containers are made with polycarbonate plastic (which often contains BPA) because it is very strong and durable. Microwave, instead, in glass or porcelain.
- For baby feeding, go bottle-free by breast-feeding when possible. If bottles are needed, choose BPA-free ones, which include glass or (as a general rule) soft or cloudy plastic bottles. BPA-containing bottles are usually hard, clear plastic. For more information, see “BPA Info for Parents” at www.hhs.gov/safety/bpa.
- Be touch-free with receipts and keep them out of recycling stream. The Environmental Working Group found surprisingly high levels of BPA on some thermal papers used for receipts, like from supermarkets, gas stations, ATMs, or airline tickets. Coincidentally, people working in retail industries had 30 percent more BPA in their bodies than the “average” U.S. adult in CDC studies. BPA is thought to rub off on hands (especially if wet or greasy), and get into the body when the hands go to the mouth. Try to minimize exposures by declining receipts at gas pumps, ATMs, etc., when possible, or using paperless purchases. Store receipts separately in an envelope in wallet/purse. Wash your hands after handling receipts (but avoid alcohol-based cleaners which may enhance BPA absorption through skin.). Finally, don’t recycle thermal paper receipts since BPA will contaminate recycled paper.
Laurine Brown is a registered dietitian and associate professor of Health and Environmental Studies at Illinois Wesleyan University. This article is reprinted with permission from Illinois Wesleyan University’s HealthWise Newsletter. References available at www.iwu.edu/~wellness.
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