Scientists issue warning about chemical in plastic

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Scientists issue warning about chemical in plastic

By Marla Cone, Times Staff Writer

6:49 PM PDT, August 2, 2007

 

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In an unusual effort targeting a single chemical, several dozen

scientists on Thursday issued a strongly worded consensus statement

warning that an estrogen-like compound in plastic is likely to be

causing an array of serious reproductive disorders in people.

 

The compound, bisphenol A or BPA, is one of the highest-volume

chemicals in the world and has found its way into the bodies of most

human beings.

 

Used to make hard plastic, BPA can seep from beverage containers and

other materials. It is used in all polycarbonate plastic baby

bottles, as well as other rigid plastic items, including large water

cooler containers, sports bottles and microwave oven dishes, along

with canned food liners and some dental sealants for children.

 

The scientists -- including four from federal health agencies --

reviewed about 700 studies before concluding that people are exposed

to levels of the chemical exceeding those that harm lab animals.

Infants and fetuses are most vulnerable, they said.

 

The statement, published online by the journal Reproductive

Toxicology, was accompanied by a new study by researchers from the

National Institutes of Health finding uterine damage in newborn

animals exposed to BPA. That damage is a possible predictor of

reproductive diseases in women, including fibroids, endometriosis,

cystic ovaries and cancers. It is the first time BPA has been linked

to female reproductive tract disorders, although earlier studies

have found early-stage prostate and breast cancer and decreased

sperm counts in animals exposed to low doses.

 

The scientists' statement and new study -- along with five

accompanying scientific reviews that summarize the 700 studies --

intensify a highly contentious debate over whether the plastic

compound poses a public threat. So far no governmental agency here

or abroad has restricted its use.

 

Representatives of the plastics industry on Thursday lambasted the

scientists as alarmist and biased, and said they based their

conclusions on inconsistent and uncertain science.

 

" Considering many of these people have made their views known in the

past, is there any surprise? Is there really anything new? " said

Steve Hentges of the American Chemistry Council's polycarbonate/BPA

group.

 

Hentges said the scientists who signed the consensus statement were

self-selected, leaving out many experts, and that many have

conflicts of interest because they have either studied BPA and

reported effects or " have already taken a very clear advocacy

position.

 

" They are completely at odds with the findings of every governmental

scientific body that has reviewed the same science, " he said.

 

Two government scientific committees in Europe and Japan recently

decided there is insufficient evidence to restrict the compound.

Europe's food safety agency decided in January that the data were

inconclusive, largely because of metabolic differences between mice

and humans, and because it is uncertain the amounts people are

exposed to pose a human health threat.

 

Next week, a U.S. expert panel convenes to decide whether to declare

BPA a human reproductive toxin, which could be a first step toward

federal regulation. The review by the panel of the federal Center

for the Evaluation of Risks to Human Reproduction, part of the

National Institutes of Health, has been controversial. The Times

reported in March that its preliminary report on BPA was written by

a consulting firm with financial ties to the chemical industry that

has since been fired by the Center.

 

Frederick vom Saal, a University of Missouri at Columbia

reproductive toxicologist, said the scientists' statement on BPA " is

very different than any other approach to any chemical. "

 

" We now have, without a doubt, the most comprehensive set of

documents covering every aspect of bisphenol A and the hope here is

that government panels will actually look at this information,

digest it, and incorporate it into their decision-making, " said vom

Saal, who is the most vocal scientist studying BPA.

 

No studies have been conducted looking for effects in people, and

one goal of the scientists who signed the statement is to generate

human research.

 

Jerrold Heindel, a scientist with the National Institute of

Environmental Health Sciences who organized a meeting last fall to

begin drafting the statement, said even though there have been no

human studies of BPA, there is now so much animal data that the 38

experts believe that potential human damage is likely. More than 150

studies have found health effects in animals exposed to low doses.

 

" We know what doses the animals were given, and when we look at

humans, we see blood levels within that range or actually higher,

which is a cause of concern and should stimulate more human

research, " he said.