BPA is just one of many estrogen-like chemicals people are exposed to, and scientists are still trying to figure out how these endocrine disruptors—including natural phyto-estrogens from soy which are often considered healthy—collectively impact human health. “But a growing body of scientific evidence suggests it might be at the cost of your health.”
Scott Belcher, PhD, and his team found when the same new and used polycarbonate drinking bottles were exposed to boiling hot water, BPA, an environmental estrogen, was released 55 times more rapidly than before exposure to hot water.
“Previous studies have shown that if you repeatedly scrub, dish-wash and boil polycarbonate baby bottles, they release BPA. That tells us that BPA can migrate from various polycarbonate plastics,” explains Belcher, UC associate professor of pharmacology and cell biophysics and corresponding study author. “But we wanted to know if ”˜normal’ use caused increased release from something that we all use, and to identify what was the most important factor that impacts release.”
“Inspired by questions from the climbing community, we went directly to tests based on how consumers use these plastic water bottles and showed that the only big difference in exposure levels revolved around liquid temperature: Bottles used for up to nine years released the same amount of BPA as new bottles.”
BPA is one of many man-made chemicals classified as endocrine disruptors, which alter the function of the endocrine system by mimicking the role of the body’s natural hormones. Hormones are secreted through endocrine glands and serve different functions throughout the body.
The chemical—which is widely used in products such as reusable water bottles, food can linings, water pipes and dental sealants—has been shown to affect reproduction and brain development in animal studies.
However, drastically higher levels of BPA were released once the bottles were briefly exposed to boiling water.
“Compared to the rate of release from the same bottle, the speed of release was 15 to 55 times faster,” explains Belcher.
Source: Journal Toxicology Letters, Jan 2008.
Aporte: Guillermo Figueroa.