ROCKVILLE, Maryland (Reuters) - A major study links a chemical widely used in plastic products, including baby bottles, to health problems in humans like heart disease and diabetes, but U.S. regulators said on Tuesday they still believe it is safe.

A nurse prepares a bottle of donated milk for a baby at Son Dureta's Hospital in Palma de Mallorca, Spain March 10, 2006. REUTERS/Dani Cardona

The chemical bisphenol A, or BPA, is commonly used in plastic food and beverage containers and in the coating of food cans.

Until now, environmental and consumer activists who have questioned the safety of BPA have relied on animal studies.

But the study by British researchers in the Journal of the American Medical Association found that among 1,455 U.S. adults, those with the highest levels of BPA were more likely to have heart disease, diabetes and liver-enzyme abnormalities than those with the lowest levels.

U.S. Food and Drug Administration officials said they would review the new findings, which were not yet published when the agency issued a draft conclusion in August that BPA is safe at current exposure levels.

“We have confidence in the data that we’ve looked at and the data that we’re relying on to say that the margin of safety is adequate,” FDA official Laura Tarantino said at a meeting of experts advising the agency on whether it made the right call.

“There are things you can do if you choose to reduce your level of bisphenol A,” Tarantino said. “But we have not recommended that anyone change their habits or change their use of any of these products because right now we don’t have the evidence in front of us to suggest that people need to.”

Panel chairman Martin Philbert declined to say what the committee’s next move would be.

BPA is used to make polycarbonate plastic, a clear shatter-resistant material in products ranging from baby bottles to medical devices.

BPA can mimic the hormone estrogen in the body.

LEACHING INTO LIQUIDS

People can consume BPA when it leaches out of the plastic into baby formula, water or food inside a container. Some retailers and manufacturers are moving away from products with BPA. Canadian officials have concluded BPA was harmful.

Steven Hentges of the American Chemistry Council, an industry group, said the study’s design did not allow for anyone to conclude BPA causes heart disease and diabetes.

“On the other hand, though, bisphenol A has been very intensively studied in a very large number of laboratory animal studies. And the weight of evidence from those studies ... continues to support the safe use of products containing bisphenol A,” he said in a telephone interview.

The British researchers, who acknowledged their findings are not proof that the chemical is causing the harm, analyzed urine samples from a U.S. government health survey of adults ages 18-74 representative of the U.S. population.

The 25 percent of people with the highest levels of bisphenol A in their bodies were more than twice as likely to have heart disease, including heart attacks or type 2 diabetes, compared to the 25 percent with the lowest levels.

At the FDA panel meeting, several scientists and activists said the FDA ignored animal studies finding health concerns and some called for the chemical to be banned in food containers.

Democratic U.S. Rep. John Dingell of Michigan, who heads the House Committee on Energy and Commerce, said the FDA has “focused myopically on industry-funded research.”

Iowa Republican Sen. Chuck Grassley, ranking member of the Committee on Finance, released a letter he wrote to FDA Commissioner Dr. Andrew von Eschenbach asking why the agency has not appointed a safety panel to review BPA.

Tarantino said nothing was ignored but industry-funded studies finding no harm were important in the conclusions. The panel is expected to present its advice to the FDA next month.

Tarantino, head of the FDA’s office of food additive safety, said there is talk of government scientists doing their own BPA safety studies, but that could take years to conduct.