This is the VOA Special English Health Report.

Bisphenol A is a chemical widely used to make hard, polycarbonate plastic. Food storage containers, reusable water bottles and baby bottles are among the many different products that may contain BPA. BPA is also commonly used in protective coverings inside metal food and drink cans.

People can swallow small amounts of BPA as they eat or drink. An industry Web site says more than forty years of safety research shows that products made with bisphenol A are safe.

But others question the safety of BPA. Now, a large study has linked it to diabetes and heart disease in adults.

Canadian Environment Minister John Baird, left, and Health Minister Tony Clement hand out baby bottles that are free of BPA. In April, Mister Clement announced Canada's plans to limit use of the chemical.

Researchers divided almost one thousand five hundred American adults into four groups based on BPA levels in their urine. All the levels were within the limits considered safe by the United States Food and Drug Administration. Yet the study found that the highest group was more than twice as likely as the lowest group to have heart disease or diabetes, or both.

The Food and Drug Administration and chemical industry officials said the study does not show that bisphenol A caused the diseases. The researcher who led the study, David Melzer at England's University of Exeter, agrees. He says the findings must be reproduced and that other studies are also needed.

But he also says that if BPA is a cause of these conditions, then just reducing contact with it might prevent some cases. The study appeared last week in the Journal of the American Medical Association.

Earlier this month, United States government scientists from the National Toxicology Program released a final report on BPA. They found that the chemical is of "some concern" for effects on development of the prostate gland and brain in fetuses, infants and children. They made the same finding for behavioral effects.

The scientists based their findings mostly on studies of laboratory animals. Even so, the program director said "the possibility that BPA may affect human development cannot be dismissed."

In April, Canada became the first country to propose a ban on plastic baby bottles that contain BPA. The government has said it will publish its final decision by October eighteenth.

Some plastic goods are now being marketed as BPA-free. But some people wonder whether any other chemicals that might take its place are any better.

And that's the VOA Special English Health Report, written by Caty Weaver. I'm Jim Tedder.