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Chemical Used in Household Plastics Sparks Concerns

October 30, 2007 at 6:35 PM EST
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BETTY ANN BOWSER, NewsHour Correspondent: When these four Washington, D.C., moms get together these days, talk turns inevitably to baby bottles.

HEIDI PARSONT, Mother: The fact that it potentially cause cancer, I think, is alarming.

BETTY ANN BOWSER: Heidi Parsont is frightened by what she’s read and heard.

HEIDI PARSONT: Some of the studies are so scary, and some of them are inconclusive, and some of them just say, you know, they don’t really know. And so it’s hard to decide how to proceed in a day and age when everything is made of this.

BETTY ANN BOWSER: The “this” Parsont is talking about is a chemical called Bisphenol A. It’s used to make millions of plastic products found in American homes, including baby bottles.

Recently, both Parenting magazine and two popular books, “Baby 411″ and “Baby Bargains,” recommended moms stop feeding their infants with polycarbonate plastic bottles. That’s because some scientists warn Bisphenol A, commonly known as BPA, is harmful, especially to young children.

While Parsont is on the fence about what to do, the other three mothers decided to throw out all of their plastic bottles and replace them with glass or BPA-free ones.

KIM TRUCANO, Mother: I also saw that there was possible — could be possible issues with the nervous system, and that worries me.

ASHLEI PUNJARA, Mother: So if I can, you know, go out and spend $30 on bottles, I’m going to do it and then have that peace of mind later. So for me, it’s about the peace of mind. It’s very difficult, because we just know just a little to get us scared.

BETTY ANN BOWSER: BPA has been used for more than 30 years to make polycarbonate plastic products shatter-resistant and optically clear. Each year, 6 billion pounds are produced around the world.

It’s not just in baby bottles. Almost every food can on the shelves at American grocery stores is lined with a resin made from BPA to prevent the metal from breaking down and affecting the contents. BPA is also found in CDs, DVDs, eyeglasses, dental sealants, bike helmets, shin guards, dinnerware, and the ever-present accessory at sporting events, the hard plastic Nalgene water bottle.

Recently, the Centers for Disease Control said it found BPA in the urine of 95 percent of over 2,000 adults tested at random. But the question nobody seems to be able to answer definitively is: Does the chemical do harm to the human body?

Thirty-eight internationally recognized scientists, all experts on BPA, recently said yes.

In an unusual consensus statement, after looking at 700 different studies on BPA, and after publishing their findings in six peer-reviewed papers, the scientists said: Adverse effects found in animals exposed to low doses of BPA gave them cause for “great concern” because of the “potential for similar adverse effects in humans.”

Developmental reproductive biologist Retha Newbold is one of the 38 who is worried about what BPA may be doing to humans.

RETHA NEWBOLD, National Institute of Environmental Health Sciences: If we look at all these things that — illnesses that are going up in the United States, there’s an increased incidence in breast cancer. There’s an increased incidence in prostate cancer. We have more problems with infertility and fertility. We do not have the direct link to say that Bisphenol A is directly associated with these lesions, but there is reason for concern that BPA is actually playing a role in some of these.

Testing BPA effects on mice

Retha Newbold
Nat'l Inst. of Environ. Health Sciences
I think for me the data is very clear using the animal models that there is reason for concern.

BETTY ANN BOWSER: In her lab here at the National Institute of Environmental Health Sciences in Research Park Triangle, North Carolina, Newbold studied the effect of low-dose BPA on mice by injecting them just five days after they were born. They were left alone, given normal food and water, and then, at about 18 months, considered late middle age in mice, Newbold studied their reproductive tracts.

RETHA NEWBOLD: When they aged out, we found paraovarian cysts. Now if you saw paraovarian cysts in a human, that would be associated with infertility or subfertility. In the mice, we also saw changes with cystic structures in the ovary.

BETTY ANN BOWSER: So what does all of this suggest for human beings?

RETHA NEWBOLD: I think for me the data is very clear using the animal models that there is reason for concern.

BETTY ANN BOWSER: Duke University epigeneticist Randy Jirtle, not one of the 38 scientists who signed the consensus statement, has also found adverse effects in mice. When pregnant mice were fed BPA in low doses, it interfered with the genetic programming of the offspring, producing yellow, instead of brown, mice. And as the yellow mice aged, they developed health problems.

RANDY JIRTLE, Professor, Duke University: The reason that they become obese is because the animal never knows that it's full and it just eats itself into obesity. And as a consequence then, it gets a higher probability of getting diabetes and cancer, like in humans.

Since we have the same system, it will be doing the same thing in human cells as we find in mice, and that is not an encouraging thought.

'Nothing to worry about'

Steven Hentges
American Chemistry Council
The position of the 38 scientists is distinctly at odds with the views of every other review of Bisphenol A that has been conducted in recent years.

BETTY ANN BOWSER: But just two weeks after the 38 scientists agreed there were major concerns about BPA, another group of internationally known, equally respected scientists, called together by the National Toxicology Program, reached a somewhat different conclusion.

EARL GRAY, Research Toxicologist, EPA: Uncertainty in the timing of exposure...

BETTY ANN BOWSER: Environmental Protection Agency research toxicologist Earl Gray was a member of that group.

EARL GRAY: We have negligible concern for the ability of Bisphenol A to affect adult reproductive health. And the next level, we had minimal concern for its ability to affect the prostate and other tissues. Some concern was expressed for the sort of neuro and behavioral changes in the fetus and the infant.

BETTY ANN BOWSER: Gray thinks, when it comes to BPA, people have nothing to worry about.

EARL GRAY: I don't know that the science gives me great cause for concern about these products with Bisphenol A.

BETTY ANN BOWSER: And Gray thinks people don't need to eliminate all products they believe contain BPA from their lives.

The chemical industry agrees. Steven Hentges thinks the 38 scientists who signed the consensus statement were predisposed against BPA. Hentges is the chief BPA scientist with the American Chemistry Council.

STEVEN HENTGES, American Chemistry Council: The position of the 38 scientists is distinctly at odds with the views of every other review of Bisphenol A that has been conducted in recent years. In every other case, scientific and government bodies with open and transparent processes which very carefully managed conflicts of interest, in every case, the conclusion from those reviews is that Bisphenol A is not a concern for human health.

Conflicting news on baby products

Amy Bremmer
Mother
I'm erring on the side of caution, because I'm just concerned about her. And so I went and got new bottles.

BETTY ANN BOWSER: The toy and baby products industry also agrees. Dr. Heather Sine is a Silver Springs, Maryland, obstetrician and consultant for the Juvenile Products Manufacturing Association.

DR. HEATHER SINE, Juvenile Products Manufacturing Association: I believe the use of Bisphenol A in plastic baby bottles poses no threat to humans, so I believe it is very safe. I base it on many studies that have been done over the years, and also I base it on the conclusions made by the FDA and also other regulatory agencies in Japan and in Europe that also have deemed them to be safe.

BETTY ANN BOWSER: So what are people supposed to do? Parents of newborns are confused.

AMY BREMMER, Mother: You read all these articles, and they're conflicting. Some of them say that, you know, don't worry. Some say it's very concerning. So, you know, I'm erring on the side of caution, because I'm just concerned about her. And so I went and got new bottles.

Identifying products with BPA

John Bucher
National Toxicology Program
I think the state of the science on Bisphenol A is somewhat unsettled....The best that I think we can do at this point is to try to be as clear as we can in interpreting the data that we have at hand.

BETTY ANN BOWSER: And even if the scientists could all agree on whether BPA is harmful or not, consumers would still have a problem. We assembled a group of plastic products -- a sippy cup, a can of tomatoes, baby food, baby bottles -- and asked neurobiologist Jennifer Sass, of an environmental advocacy group, how to tell which ones contain BPA.

JENNIFER SASS, National Resources Defense Council: Some do, and some don't. And the problem is the consumer doesn't have a reliable way of knowing the difference.

BETTY ANN BOWSER: Sass says, if a plastic product is clear and hard, it is most likely to contain BPA. And unless the federal government were to require labeling, consumers can only make an educated guess.

JENNIFER SASS: And what they're going to need to do, unfortunately, is phone up the companies that they're interested in or phone up the Food and Drug Administration and have the government provide information. But preferably moving away from plastics is the best choice, if you can.

BETTY ANN BOWSER: John Bucher is the man who's been given the Herculean job of reviewing all the studies, both pro and con, and coming up with recommendations for federal agencies about what to do.

JOHN BUCHER, Associate Director, National Toxicology Program: I think the state of the science on Bisphenol A is somewhat unsettled. This is not unusual in environmental health sciences. The best that I think we can do at this point is to try to be as clear as we can in interpreting the data that we have at hand.

BETTY ANN BOWSER: Until that happens, consumers are pretty much on their own, with only a few exceptions. Several manufacturers recently started making baby bottles without BPA, and many stores, like Babies "R" Us, are selling them.

GWEN IFILL: You can send questions to experts on both sides of the BPA issue. To participate in our online forum, go to PBS.org.