Are polycarbonate containers such as those used by Brita dangerous to
one's health because of possible leeching of BPA or is the danger so
remote as to be negligible?

Hello, rce-ga!

 According to a published study in Environmental Health Perspectives,
the scientific opinions concerning the potential danger from BPA's may
be slanted, depending on who conducts the research. And considering
that most of the research has been done on mice as opposed to humans,
there is further room for argument.

 Ultimately, this is one of those areas where it will be up to you to
judge how much "potential" risk you will tolerate. If, after reading
the following references, you decide it is not worth putting your
health at risk, you can easily switch over to glass containers.
 
==

From "Debate over a leaching chemical heats up," by Elizabeth Weise,
USA TODAY. 4/14/2005
http://www.usatoday.com/news/health/2005-04-14-leaching-chemical_x.htm

"Is it possible that a chemical's effect is in the eye of the
beholder? That's the implication of a paper published this week in a
prominent environmental health journal. It concerns a debate over the
safety of low doses of a chemical used to make hard, clear plastics
such as those found in baby bottles, food-storage containers and the
lining of soda cans."

* "When the plastic industry examines the health impact of a
ubiquitous chemical called bisphenol A, everything's fine."

* "If the government or a university funds the study, there are big problems."

"Those are the conclusions drawn by Frederick vom Saal, a
developmental biologist at the University of Missouri who reports his
findings in Environmental Health Perspectives, published by the
National Institute of Environmental Health Sciences. Vom Saal and
others seek revised risk assessments for the chemical in the light of
a new research into its effects."

"Vom Saal looked at 115 published studies concerning low-doses of
bisphenol A. Overall, 94 of them reported significant effects in rats
and mice, while 21 did not."

"Eleven of the studies were funded by chemical companies. None of
those 11 found harmful effects of the chemical, which the Centers for
Disease Control and Prevention says is detected in 95% of all people
tested."

"But more than 90% of the studies conducted by independent scientists
not associated with the chemical industry found adverse consequences,
says vom Saal. He called the disparity between the industry and
government or university conclusions "stunning."

(Read further...

====

Another commentary concerning vom Saal's findings:

From "Study: Common plastic a threat," by Douglas Fischer. Inside Bay Area
http://www.insidebayarea.com/bodyburden/ci_2852788


"Mounting evidence suggests a plastic additive common in baby and
sports bottles and used to line the inside of soda and tin cans is
accumulating in our bodies at levels far beyond those known to cause
considerable health problems in lab animals. At least that's the
conclusion in research underwritten by the government or an
independent source such as a university, a new review of 115
peer-reviewed publications has found. Industry-sponsored research has
so far found no problem with the additive, bisphenol-A."

"Bisphenol-A's menace, said lead author Frederick vom Saal, is that in
low doses the additive acts almost identically to hormones in birth
control pills. The body is extremely sensitive to hormones, with
extremely tiny amounts able to trigger a cascade of events. Vom Saal,
a researcher at the University of Missouri, Columbia, said the low
doses found in the environment pose a grave concern for fetuses and
the very young."

"This chemical we once thought was very weak is an extremely potent
sex hormone," vom Saal said. "The problem with bisphenol-A is it
disrupts almost the entire reproductive system as well as brain
function.

"When fetuses are exposed ... all of these systems are permanently
damaged by a sex hormone-like chemical like bisphenol-A. These organs
can never function properly again."

...

"Industry and other experts took sharp issue with the review's
analysis, criticizing the authors' willingness to imply an effect
found in laboratory animals also would impact humans. They also
questioned why vom Saal discounts credible research showing little or
no environmental impact from bisphenol-A.

"We know nothing about the link between hyperactivity in animals and
hyperactivity in humans," said George Gray, executive director of the
Harvard Center for Risk Analysis, a predominately industry-supported
group that conducted one of the studies vom Saal skewered.
"Governments around the world have spent a lot of time looking at
this."

"Indeed, the United States, Japan and the European Union have all
concluded the compound poses no threat to humans at levels found in
the environment, said Steve Hentges, executive director of the
polycarbonate business unit for the American Plastics Council."

"The sum of weak evidence doesn't make strong evidence," he said.
"Based on the weight of the evidence, we continue to be very confident
there is no risk to human health."


====


According to a recent Japanese study, higher serum levels of BPA in
pregnant women may induce miscarriage:


From "Exposure to bisphenol A is associated with recurrent
miscarriage." Sugiura-Ogasawara, M, Y Ozaki, S Sonta, T Makino and
Kaoru Suzumori 2005. Human Reproduction.
http://www.ourstolenfuture.org/NewScience/oncompounds/bisphenola/2005/2005-0610Sugiuraetal.htm

"With this study, Sugiura-Ogasawara et al. provide the first,
indication that BPA is associated with recurrent miscarriage in
people, as predicted by Hunt et al.'s results. They found higher
levels of BPA in women with a history of recurrent miscarriage, and
evidence of meiotic aneuploidy in their miscarried fetuses."
 
"In their prospective study, Sugiura- Ogasawara et al. compared BPA
levels in the serum of 45 women with a history of recurrent
miscarriage to serum levels in 32 pregnant women with histories of
successful pregnancies. They tracked the women through their next
pregnancy to see whether it was successful. They also examined the
miscarried fetuses of unsuccessful pregnancies for evidence of
chromosomal damage consistent with aneuploidy. In addition, they
examined the women for several immune system parameters and thyroid
levels."

"Bisphenol A levels were more than three times higher in women with a
history of recurrent miscarriage (2.59 ng/mL vs. 0.77 ng/mL). This
difference was statistically significant (p = 0.024)."

What does it mean? - "This is a preliminary study with a small sample
size. Despite the small sample, the fact that Sugiura- Ogasawara et
al. found a significantly higher BPA levels in mothers experiencing
recurrent miscarriage is a worrisome tentative confirmation of
predictions from animal studies. Clearly this work requires
replication with a much larger sample size. But the fact that this is
a predicted result based on solid animal research increases its
plausibility even with a small sample."

==

The BisphenolA website has a good selection of up-to-date research
studies but it may be biased as well!
http://www.bisphenol-a.org/index.html

One of the latest reports:

From "Biomonitoring Studies Confirm Human Exposure to Bisphenol A is
Very Low -Low Exposure Supports Low Risk to Human Health." May 4, 2005


Summary:

"Biomonitoring data on bisphenol A (BPA) have been reported in a
number of studies worldwide. These studies consistently indicate that
human daily intake of bisphenol A is very low and likely to be in the
range of 20-30 nanograms/kg-body weight/day for adults. These levels
are about 1,000,000 times below the levels where no adverse effects on
reproduction and development were observed in multi-generation animal
studies. Similarly, these levels are about 400-2,000 times below
lifetime daily intake levels set by government bodies in the US and
Europe. Exposures below the lifetime daily intake levels are expected
to have no adverse effect on health. Both comparisons indicate a
substantial margin of safety between actual and safe exposure levels.
Overall, the available biomonitoring data on bisphenol A supports the
conclusion that exposure to bisphenol A from all sources poses no
known risk to human health."

Read entire report.... 


==


 I hope this overview has been of some help. As is the case with much
scientific research, individuals often have to make their own choices
before all the evidence is in.

Sincerely,

umiat


Search Strategy

is bisphenol A dangerous to humans?
research and BPA
BPA health risk

The disparity between the industry and non-profit studies is, indeed,
the central problem.  It is quite possible that the n-p's have a bias
as well, although it seems less likely. The Hunt Study is quite
convincing, but its reliance upon effects in mice (and the inevitable
industry attack about relative exposure levels) makes a decision about
risk levels difficult. Thanks for the Japanese study reference; that
provides a credible potential link.