slide3BPA In Water Bottles And Other Plastic Products
Summer's almost fully upon us, and the hotter we get, the more water we drink. But, what about those rumors we've heard about plastic water bottles causing cancer? We'll never forget when Sheryl Crow attributed her breast cancer to the BPA (Bisphenol A, a chemical used in plastics) in re-used water bottles.

According to Shanaz H. Dairkee, Ph.D., a Senior Scientist of Cancer Research at the California Pacific Medical Center Research Institute and Consulting Professor at the Stanford University School of Medicine, BPA is all around us, everywhere. "We are swimming in it," she says. "In our homes, workplaces, schools, and recreation areas." She points out that it's used to line food cans and paper plates, in beverage bottles, and even in cash register receipts.

Beverly Rubin, Ph.D., Associate Professor of Anatomy & Cellular Biology at Tufts University, says BPA is also in the soil, ground water, and in the dust that collects both indoors and outdoors. And, it's not just around us: a whopping 93% of people in the U.S. have appreciable levels of BPA in their urine, according to Cheryl S. Watson, Ph.D, the editor-in-chief of Endocrine Disruptors (Landes Bioscience Journals) and professor of bio-chemistry and molecular biology at the University of Texas Medical Branch. Dr. Dairkee says that BPA has also been found in human blood, breast milk, and fetal liver — which indicates that BPA can cross the placenta.

The danger of BPA in our bodies lies in its relationship to estrogen, Dr. Watson says. "BPA resembles (but is not exactly like) natural estrogens, and can mimic or disrupt the actions of the body’s own estrogens, for both males and females." When a body has too much estrogen, Dr. Dairkee says, it can initiate cancer and precancerous lesions in estrogen-sensitive tissues. The effect has been proven in animals, with results that repeat across species. Though this isn't technically direct evidence that BPA causes cancer in humans, humans are indeed animals, and the results of these tests should be taken seriously.

So, should you ditch your water bottle? Dr. Dairkee says that re-using plastic does indeed cause more BPA to leach out of the product. And, it's even worse for water bottles left in the sun or in a hot car, as the sun causes the chemicals in the plastic to leak into the beverage — a process that occurs at a faster rate in a warm environment. While we can try to avoid using products that contain BPA as much as possible by using glass water bottles, Dr. Dairkee says that using BPA-free products isn't necessarily a safer option —  because the replacement compounds haven't been reliably tested yet. "Current regulatory requirements in the U.S. do not place the burden of proof on the manufacturer, which is why there is almost no incentive to pre-test chemicals for safe consumption," she explains.

The bottom line: To minimize your cancer risk, stay away from BPA. "A chemical such as BPA, which is not only persistent but disruptive for normal functioning right down to the level of individual cells in the human body, should be avoided to the best of one’s ability," Dr. Dairkee says.