WASHINGTON (Reuters) - Canada is moving to get rid of products with a chemical common in plastic baby bottles, the United States is expressing concern over its safety and some retailers are planning to stop selling these items.

Baby bottles free of the chemical bisphenol A are seen during a news conference with Canada's Health Minister Tony Clement in Ottawa April 18, 2008. Canada intends to ban the import and sale of plastic polycarbonate baby bottles, which would be the first such step in the world, Clement said on Friday. REUTERS/Chris Wattie

But whether the chemical bisphenol A poses genuine health risks in people remains a matter of debate, with industry groups defending its safety and environmental activists saying studies involving animals show otherwise.

Bisphenol A, or BPA, is used to make polycarbonate plastic, a clear shatter-resistant material in products ranging from plastic baby and water bottles to sports safety equipment and medical devices.

It also is used to make durable epoxy resins used as the coating in most food and beverage cans.

People can eat or drink the chemical when it leaches out of the plastic into liquid such as baby formula, water or food inside the container.

“At this point, the writing is on the wall for bisphenol A. Major retailers and governments all across the country and the world are now recognizing that this chemical is extremely toxic at very low levels of exposure,” Michael Schade of the U.S. environmental group Center for Health, Environment and Justice said in a telephone interview.

Critics of BPA said more than 150 scientific studies involving laboratory rodents show BPA to be harmful at even low levels. But some experts are not convinced.

“For me, the big question is: what levels of exposures are we getting and are those levels of exposure sufficient to cause harm?” Carl Winter, director of the Food Safety Program at the University of California-Davis, said in a telephone interview.

“There still does not exist strong evidence supporting significant impacts on human health for bisphenol A,” he said.

“NEGLIGIBLE RISK”

Steven Hentges of the American Chemistry Council downplayed the animal studies, saying they “have not been corroborated between labs and the entire data set is not coherent.”

He added: “We do believe that bisphenol A poses negligible risk to human health.”

On Tuesday the National Toxicology Program, part of the U.S. government’s National Institutes of Health, issued a draft report expressing concern that BPA could cause neural and behavioral problems in fetuses, infants and children.

Relying on the results of animal studies, it expressed concern about possible links between BPA exposure and early puberty and prostate and breast cancer.

Dr. Anila Jacob of the activist Environmental Working Group said using rodent studies to assess toxicity is a well-established practice given that scientists cannot expose humans to possible toxins in research for ethical reasons.

Canadian Health Minister Tony Clement said on Friday his country intends to become the first to ban the import and sale of some types of plastic baby bottles because they contain BPA. He expressed concern that overexposure at an early age could cause later behavioral and neurological symptoms.

Wal-Mart, the world’s largest retailer, announced on Thursday it plans to offer more BPA-free products and intends to stop selling baby bottles made with BPA early next year.

Rochester, New York-based bottle maker Nalgene said on Friday it will phase out production of bottles made with BPA. Nalgene is owned by Thermo Fisher Scientific Inc.

U.S. states including California, Maryland, Minnesota and Michigan are considering bills to ban or restrict bisphenol A in children’s products.

In Washington, Democratic Reps. John Dingell and Bart Stupak have been investigating BPA in products intended for use by infants and children. They are calling on the Food and Drug Administration to reconsider its view that it is safe.