Possibly a great deal, say scientists who’ve linked bisphenol-A, or BPA �?a chemical found in a wide array of hard-plastic products used for eating and drinking �?to severe health problems, including miscarriages, cancers and brain disorders in studies involving animals.

Such concerns prompted Canada on Friday to declare BPA a toxic chemical, a decision that could lead to a Canada-wide ban of BPA in baby bottles.

The same day, Nalgene announced that it’s phasing out production of all water bottles containing BPA, though the company maintained that there is nothing dangerous in the plastic.

"Based on all available scientific evidence, we continue to believe that Nalgene products containing BPA are safe for their intended use," said general manager Stephen Silverman, in a press release. "However, our customers indicated they preferred BPA-free alternatives."

Since 2005, more than 130 studies have examined the low-dose effects of BPA on animals and humans, according to Fred vom Saal, a toxicologist at the University of Missouri and lead author of a study that appeared last fall in the journal Reproductive Toxicology.

That report noted that BPA is a known endocrine disrupter, a chemical that affects the hormonal system, which leads to a range of adverse effects in animals �?and possibly humans.

"Based on existing data, we are confident �?that similar effects are also occurring in humans," the study concluded. Some of those risks might include:

�?Miscarriage: A Japanese study found that women with frequent miscarriages, on average, have three times more BPA in their blood serum as women with successful pregnancies do.

�?Cancers: Animal studies show an increased risk for breast cancer among mice exposed to low doses of BPA prior to birth, and cell culture studies show that the presence of BPA may pose problems for men battling prostate cancer.

�?Brain disorders: BPA exposure in the womb �?at levels lower than doses considered safe by the EPA �?modified the brain in rats in a manner that confused their sexual identities, resulting in the demasculinization of males and the defeminization of females, according to a study in Japan.

New concerns posed by chemicals in a wide array of common plastic household products �?including the phthalates (pronounced "thal-ates") in soft plastic toys popular with children �?drew special attention during a recent conference of Alaska public health nurses in Anchorage.

"What this is indicative of is a failed chemical policy in the United States," said Barbara Sattler, director of the graduate program in environmental health at the University of Maryland.

Echoing that sentiment in another venue was Mark Schapiro, author of "Exposed," a book on toxic chemistry in everyday products, who says the United States is moving far slower than other developed nations in banning or restricting potentially toxic chemicals.

"Phthalates were banned eight years ago in the European Union (nations)," Schapiro said last week in a statewide teleconference sponsored by the Alaska Community Action on Toxics organization.

"The United States is becoming a dumping ground for a lot of products that cannot be sold in the rest of the world."

If Canada bans BPA in baby bottles, it would be the first nation to do so, but others could soon follow.

Last week, the U.S. Department of Health and Human Services, through its National Toxicology Program, endorsed the research by vom Saal and 30 other scientists in concluding there is "some concern" about risks for neural and behavioral changes in humans who consume BPA.

© 2008 Anchorage Daily News