Bisphenol A, known as BPA, is a toxic chemical found in polycarbonate plastic — a hard, translucent plastic, usually marked with recycling symbol (SPI) No. 7. Often used to coat metal, it can be found in water pipes and the resinous lining of food and beverage cans. It is also used for dental fillings, baby bottles and formula containers, water coolers and bottles, tableware, food storage and to-go containers. BPA can seep out of polycarbonate plastic into food and liquid, in particular when the plastic is heated, worn or scratched, or when in contact with fatty or acidic foods.

First developed in 1891, it was considered for use as a way to replace estrogen. Indeed, BPA’s ability to mimic and disrupt hormones is what makes it so scary. Hormones stimulate certain cancers, which is why BPA is associated with prostate and breast cancer. A known endocrine inhibitor, BPA can interfere with metabolism, sex organs and neurological and reproductive development. It has been strongly linked to obesity, heart and liver disease, diabetes, early puberty, and learning and behavioral problems. Exposure in the womb to bisphenol A and phthalates (the chemical found in PVC) are two of the most likely causes of the genital abnormalities that are now the most common birth defects in American baby boys.

Over 100 independent studies have confirmed the concerns surrounding BPA, and 92 percent of 163 government-funded studies found “significant negative effects” from low-level exposure. That’s serious stuff in the lingo of science research. In fact, the only studies that have not found “significant effects” seem to be funded by the chemical industry. Imagine that.

While the FDA continues to state that BPAs are “safe” (guess whose studies they considered?), the Journal of the American Medical Association, The National Toxicology Program — part of the Department of Health and Human Services — and other prominent health institutes have all raised concerns about BPA. A Centers for Disease Control and Prevention (CDC) study found detectable levels of BPA in 93 percent of urine samples collected. Keep in mind, the FDA has tested less than 15 percent of 100,000 chemicals in use; their claim that bisphenol A is “safe” is not exactly reassuring.

The effects of BPA on fetuses and young children is far greater than for adults, so the suggestions below are particularly important for pregnant and nursing women, babies and children. As Dr. Shanna Swan, Director of the Center for Reproductive Epidemiology at the University of Rochester School of Medicine and Dentistry, points out, “These fetal effects are permanent and irreversible.” A note to pregnant women, or those who might become pregnant: bisphenol A is associated with miscarriages as well as birth defects.

So what to do? To stay on the green and healthy side of precaution, here are some guidelines:

• Use glass, stainless steel, paper, cloth, or ceramic containers for your food and beverages. If you feel you have to use plastic, SPI 4, 5, 1 & 2 are considered the safer options. Not all SPI 7 plastic contains BPA, but unless it is specifically labeled as "BPA-free," it's hard to know which do or don't.

• Never heat food in plastic, or put warm or hot food into plastic containers (that includes plastic cling wraps). Remember that “microwave safe” only means that the container or cling wrap won’t deform; it has nothing to do with your safety.

• Avoid contact between fatty or acidic foods and plastic.

• Recycle any worn or scratched plastic, and don’t put plastic in the dishwasher.

• Breastfeed. If not, use glass bottles and buy un-canned, powdered formula.

• Don’t buy canned foods or beverages. Really.

• Wrap sandwiches in cloth or paper, and bring your own utensils. If you use a plastic reusable bottle (like Nalgene), make sure it is BPA-free.

• Invest in a filter, and keep water in glass or ceramic or stainless steel containers. Most water coolers, and the bottles that go with them, contain bisphenol A.

• Check what type of plastic your food processor is made from. Replace plastic coffee filters with ceramic or metal ones.

• Write to food companies and urge them to use less harmful alternatives to SPI 3, 6 and 7 plastics. Do the same for places you shop, and restaurants where you get food to go.

• In 1996 Bill Clinton signed the “Food Quality Protection Act” which promised a screening of endocrine inhibitors by the EPA. By 2007, although they had spent $80 million on the endocrine disruptor program, the EPA had still not tested a single one of the 15,000 chemicals promised. Tell the EPA it’s time to get to work, and demand the FDA get serious about studying BPA.

Hope this is helpful — even if alarming.

How can I avoid BPA?
Bisphenol A, known as BPA, is a toxic chemical found in polycarbonate plastic — a hard, translucent plastic, usually marked with recycling symbol No. 7.