Bisphenol-A
Recently, Patagonia and MEC have pulled all polycarbonate-type containers (e.g. Lexan) from their shelves, as Bisphenol-A (BPA) leeches from it into the liquid contained therein -- and hence into your body. It is widely used in our food chain, as it has been considered "Safe" after more-strict safety regulations from the 1980's "grandfathered" it (presumably among many other substances). It is used to line most food cans, for example. Humanity makes more than 6.4 billion pounds of BPA-containing plastics a year.
ehponline.org
A recent report prepared by the Harvard Center for Risk Analysis and funded by the American Plastics Council concluded that evidence for low-dose effects of BPA is weak on the basis of a review of only 19 studies; the report was issued after a delay of 2.5 years. A current comprehensive review of the literature reveals that the opposite is true. As of December 2004, there were 115 published in vivo studies concerning low-dose effects of BPA, and 94 of these report significant effects. In 31 publications with vertebrate and invertebrate animals, significant effects occurred below the predicted "safe" or reference dose of 50 gkg/day BPA.
Nonetheless, chemical manufacturers continue to discount these published findings because no industry-funded studies have reported significant effects of low doses of BPA, although > 90% of government-funded studies have reported significant effects. Some industry-funded studies have ignored the results of positive controls, and many studies reporting no significant effects used a strain of rat that is inappropriate for the study of estrogenic responses. -- Environmental Health Perspectives Volume 113, Number 8, August 2005.
According to Wikipedia BPA was first discovered in the late 1800's and was further investigated as an estrogen replacement in the 1930's. It was found to be "okay" but a similar phenol was slightly better. BPA is found in all humans in so-called "developed" countries.
At very low doses (~2 gkg/day or less -- babies fed canned formula in polycarbonate bottles can get up to 13gkg/day) BPA causes permanent genital tract changes, changes in breast tissues, 30% increase in prostate mass, early puberty, declines in testicular testosterone and more predisposition to genital and breast cancer.
Health Canada has performed a more-recent assessment and determined that it should be declared a "dangerous chemical". Results will allegedly be released on Wednesday. A news article from the Globe and Mail states:
Globe and Mail
Health Canada is calling bisphenol A a dangerous substance, making it the first regulatory body in the world to reach such a determination and taking the initial step toward measures to control exposures to it.
Although the government won't announce specific bans or restrictions, the designation as dangerous could pave the way for the hormonally active chemical to be listed as toxic under the Canadian Environmental Protection Act, which would allow Health Minister Tony Clement to issue specific measures to curb its use.
An article from Salon.com says:
Salon.com
The American Chemistry Council tells us that bisphenol A makes our lives "healthier and safer, each and every day." But accumulating scientific research indicates the chemical may be adversely affecting women's ability to have children and children's reproductive health. Recent studies link bisphenol A to obesity, breast and prostate cancer, and neurological disorders.
Bisphenol A is a building block of the durable light plastics used in consumer products ranging from baby bottles to coffee makers to laptop computers, CDs to dental sealants to food can liners. It's a key ingredient of car parts, water filters, textiles, paper and a widely used flame retardant. "Everyone is exposed to it," says Dr. Hugh S. Taylor, reproductive endocrinologist at Yale University School of Medicine, who is studying the impact of the chemical on female reproductive health.
[..]
While bisphenol A has earned approval by the U.S. Food and Drug Administration for what are called "food contact" consumer products, the Centers for Disease Control has found bisphenol A in 95 percent of tested Americans at or above levels that have been found to cause abnormalities in animals.