Day: April 9, 2007

Bisphenol A – Getting More Powerful Everyday

So is it Mondays with Bisphenol?? You know what, the scary thing about this chemical is that its acute (short term, immediate) toxicity at high doses, which is the only safety testing that is ever done, does not correlate with all the subtle effects that are seen at low doses (chronic). Here’s another study where ambient level exposure to bisphenol A interferes with prostate cancer treatment by making the tumor cells androgen independent, so the standard testosterone deprivation therapy will not work any more.

Environmental Health News: New Science

A common plastic molecule to which virtually all Americans are exposed may interfere with the standard medical treatment for prostate cancer, according to new experiments with human prostate tumors implanted into mice. The doses of the plastic molecule, bisphenol A, were chosen specifically to be within the range of common human exposures. Tumor size and PSA levels were significantly greater in exposed animals just one month after treatment.

One of the principal known sources of exposure to bisphenol A in the U.S. is through its use to make a resin that lines the majority of food cans sold in markets. These new results by Wetherill et al. suggest men concerned about prostate cancer may want to reduce their consumption of canned goods and their use of polycarbonate water bottles, another common source of exposure

This is one powerful (if not actually more dangerous) chemical. it is so ubiquitous that finding a substitute is not going to be easy.

Glass baby bottles making comeback

More Bisphenol A blowback, apparently, SF parents are switching to glass.

Glass baby bottles making comeback / Stores selling out after health alarms raised about plastics

Glass baby bottles, replaced decades ago by unbreakable plastic, are making such a comeback that parents can’t get their hands on them.

Online and brick-and-mortar retailers report a run on glass baby bottles in recent weeks that they say was spurred by reports that the most common type of plastic in baby bottles may leach a toxic chemical.

San Francisco resident Sean Mullins said he decided to switch his 6-month-old son, Mickey, from plastic to glass bottles last month despite manufacturers’ insistence that plastic bottles are safe.

Independent tests done for The Chronicle and reported in November found bisphenol A, a chemical that mimics estrogen, in a baby bottle and several toys. Bisphenol A is also found in the lining of food cans, some anti-cavity sealants for teeth, and electronics.

Watch for plastics manufacturers to fight back, this study ought to provide some ammo.

Comparison of six samples of each of three brands of water available in both glass and polyethyelene terephthalate (PET(E)) showed that the waters bottled in glass contained approximately 57, 30, and 26 times more Pb due to leaching from the containers. Our study includes 25 brands of bottled water from Canada, and the median Pb concentration in these samples was 15.9 ng/L (n = 25), with a range from 2.1 to 268 ng/L. For comparison with the bottled waters, pristine groundwater from six artesian flows in southern Ontario, Canada, where some of the bottled waters originate, yielded a median concentration of 5.1 ng/L Pb (n = 18). In fact, all of the waters tested were well below the maximum allowable concentration established by the EU, Health Canada, and the WHO for Pb in drinking water (10000 ng/L).

It all depends on which bolded sentence you chose to emphasize! So, glass bottles do leach some lead out, but nowhere near the amount needed to cause any effects whatsoever. I guess this is all the American Chemistry Council can come up with as a problem with glass.

It’s irrefutable that glass can shatter, Hentges said. But there is “no scientific basis to conclude that BPA is something to be concerned about … at the extremely low levels that people might be exposed to from use of consumer products.”

There is plenty of scientific basis to conclude that Bisphenol A has some very subtle effects at ambient doses. But science has never stopped the American Chemistry Council!