OT: Now Baby Bottles are Toxic - what's next?

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Chemical in baby bottles may pose risk

Scientists, industry await U.S. report on health risk from BPA, made

in Texas

07:45 AM CDT on Friday, August 3, 2007

By SUE GOETINCK AMBROSE / The Dallas Morning News

sgoetinck@...

Next week, a federally appointed panel of scientists is scheduled to

finish its evaluation on the health risks of an industrial chemical,

widely used in baby bottles, food cans and other consumer products,

that many researchers believe poses risks to human reproduction and

development.

Also Online

Link: Read the National Toxicology Program's full report and public

comments

But in a news briefing Thursday, a separate group of university and

government scientists said they have reached their own conclusion –

that there is ample reason to fear that the chemical is, in fact,

causing adverse human health effects – including possible abnormal

development of reproductive organs and predisposition to cancer.

The chemical in question, bisphenol A (BPA), the basic building block

of polycarbonate plastic, also mimics the female hormone estrogen. An

estimated 95 percent of Americans have it flowing through their

bodies – and Texas is a major producer of the chemical.

Industry representatives insist that BPA, in its current use, does

not pose a risk to human health. But experiments on lab rodents

within the last decade have found that BPA decreases fertility in

both sexes after adult exposure. It can also cause reproductive and

behavioral problems when developing males and females are exposed to

low doses in the womb.

Two years ago, the National Toxicology Program, part of the National

Institutes of Health, set up the panel to review scientific studies

on BPA and assess the risk the chemical poses to human reproduction.

Studies have shown that BPA can leach out of products – like plastic

bottles and food can linings – and that the chemical is widespread in

the environment, including in air and household dust. In one study on

almost 400 Americans, the Centers for Disease Control and Prevention

found BPA in urine samples in more than 95 percent of the subjects.

Scientists have reported that in tests on animals, BPA disrupted

sperm production and caused problems in the male reproductive tract.

Other studies suggested abnormal, possibly precancerous changes to

the uterus, mammary tissue and prostate gland. Many of these changes

showed up in adulthood after animals were exposed to BPA in the womb

or as newborns. Other studies – mostly funded by the chemical

industry – have claimed little or no effect of BPA.

And this week, Duke University researchers reported in the

Proceedings of the National Academy of Sciences that exposure to

prenatal BPA reprogrammed a gene, causing mice that were normally

brown to develop yellow coats. Genetic reprogramming, a relatively

new area of research, is thought to contribute to a variety of

illnesses, including cancer.

There are already indications that the public is taking notice. Baby

bottles and sippy cups made without BPA are on the market; a popular

baby book has recommended buying products free of BPA; and Norway has

proposed a ban on BPA.

Controversial review

The review process, which invites public comments, has stirred

vehement controversy. Several university scientists have accused the

government-appointed panel of favoring chemical industry studies that

have found no harmful effects of BPA. This spring, the government

terminated the contractor hired to prepare the initial summary of BPA

studies for the review panel, because of the contractor's ties to the

chemical industry.

A coalition of university and government scientists decided to put

together its own review of BPA. Their findings, published recently in

a scientific journal, were discussed in Thursday's conference call

with news media.

" There is a very high level of concern that humans are being impacted

by the levels of BPA that they are currently exposed to, " said Fred

vom Saal, a biologist at the University of Missouri-Columbia and lead

author of the group's summary report.

During the news briefing, scientists discussed a published study on

mice that found that exposure to BPA just after birth causes many of

the problems that DES, a now-banned anti-miscarriage drug, causes in

women. These include ovarian cysts, fibroids and precancerous growth

later in life.

Another paper published this week included a prediction that humans

may well be exposed to more than 10 times the daily dose of BPA

deemed safe by the Environmental Protection Agency. The American

Chemistry Council, an industry group, has found fault with both

papers.

The federal government's review panel is scheduled to meet Monday

through Wednesday to finalize its report. After the review panel

reaches its conclusions, the National Toxicology Program will compile

a final report. A strong indictment of BPA could force stronger

regulations and affect the chemical industry.

" I can't say which way the panel will go, " said Vandenbergh, a

member of the panel and an emeritus professor at North Carolina State

University.

" Is the draft perfect? " asked Hentges, executive director of

the Polycarbonate/BPA Global Group at the American Chemistry Council,

an institute that represents the chemical industry. " Not yet, but

it's better " than an earlier version.

Dr. vom Saal said the panel's findings will come under intense

scrutiny. " What I can tell you is if the panel totally ignores the

criticism, all hell is going to break loose, " he said.

Economically, the stakes are high.

Global production capacity for BPA is 8.2 billion pounds per year,

according to chemical industry analysts. U.S. production capacity is

estimated at 2.3 billion pounds – and half of that is in Texas plants

owned by Dow, Bayer and Hexion Specialty Chemicals.

Bisphenol A was studied early last century as a synthetic estrogen.

Chemists later realized that molecules of BPA could be strung

together to make polycarbonate, a form of plastic.

Conflict of interest

Since the late 1990s, there have been allegations that the chemical

industry has distorted science to show that BPA poses no threat to

human health. The allegations of bias have carried over to the

government's current evaluation.

After the government terminated its contract with Sciences

International Inc., an audit concluded that the studies that the

contractor compiled for the review panel were largely appropriate and

complete. But several scientists and environmental groups have

complained that the contractor's work was biased and contained

factual errors. Researchers have also complained that the panel

includes no BPA researchers, a strategy the government says avoids

preconceptions on the part of panel members.

Dr. Vandenbergh, a member of the government-appointed panel, said he

spot-checked the initial summary with the original studies and found

few errors.But Ana Soto, a biologist at Boston's Tufts University

School of Medicine, charged that revisions to the panel's draft

report, carried out after Sciences International was dropped, still

favored the chemical industry.

Dr. Soto noted that 12 out of 17 industry-funded studies – about 70

percent – were deemed adequate for the panel's evaluation. But only

27 out of 89 non-industry-funded studies – about 30 percent – were

deemed adequate. The Dallas Morning News confirmed Dr. Soto's

numbers.

Dr. Hentges, of the American Chemistry Council, dismissed that

criticism.

" Who did [the study] is not really the question " he said. " It's the

science, and the science stands on its own merits. She's comparing

different study design and quality. "

In fact, study design and quality are another point of contention.

The Dallas Morning News confirmed – as several scientists noted in

their public comments – that the review panel has so far retained a

study, despite a failed " positive control " – an internal check that

scientists use to confirm whether an experiment worked as intended.

Despite the control's failure, the scientists, who were funded by the

chemical industry, concluded that BPA did not harm the reproductive

system.

The News also discovered factual inconsistencies in the portion of

the panel's draft report dealing with BPA levels in human blood. For

example, a table claiming to summarize BPA levels in human blood

omitted data indicating some of the highest blood levels reported.

Also, two studies that report BPA blood levels and that are openly

available are not cited in the draft.

'Misleading summary'

The News pointed out these omissions to Wade Welshons, a BPA

researcher at the University of Missouri, who said they were a

serious oversight.

" It gives a very incorrect, misleading summary of the literature, " he

said. " The effect is that it dilutes the impact of actual measures of

BPA in human blood. "

The final draft from the expert panel is expected to be released soon

after next week's meeting.