The Food and Drug Administration on Friday declared the levels of bisphenol A (BPA) in baby bottles and other household products safe despite serious evidence that the chemical might cause cancer or lead to early or delayed puberty. However, the agency agreed that more research is required to understand BPA’s effects on humans because “there are always uncertainties associated with safety decisions.”

The food agency “has concluded that an adequate margin of safety exists,” a draft report on its Web site said.

BPA is a synthetic hormone (similar to estrogen) that has been shown to leach out of certain type of plastic when heated, endangering the health of consumers. The chemical is used to seal food cans and to prevent liquids from shattering out of bottles; it is also used in making sunglasses or even CDs. It makes plastic stronger.

According to the Centers for Disease Control and Prevention around 93percent of Americans have traces of bisphenol in their urine, but this percentage is not at all harmful.

A report by the National Toxicology Program, part of the U.S. National Institutes of Health revealed in mid-April that their study on mice given BPA on regular basis resulted in precancerous prostate tumors, urinary system problems and early puberty when the animals were given low doses of the chemical.

“However, because these effects in animals occur at bisphenol A exposure levels similar to those experienced by humans, the possibility that bisphenol A may alter human development cannot be dismissed,” the report concluded.

The report was highly contested by plastic industry representatives who called the lab experiments inconclusive and flawed. But its results have been confirmed in time by other studies making consumers anxious over the possible adverse effects of BPA.

The FDA’s decision was highly praised by the American Chemistry Council, which represents the chemical industry.

“FDA’s thorough analysis confirms that food contact products made from polycarbonate plastic including products for infants and children, can continue to be used safely,” Steven G. Hentges managing director of the ACC said.

However, environmental groups said the FDA’s decision relied only on industry-funded studies and therefore it is not reliable.

“It’s ironic FDA would choose to ignore dozens of studies funded by (the National Institutes of Health) – this country’s best scientists – and instead rely on flawed studies from industry,” Pete Myers, chief scientist for Environmental Health Sciences, said.

Canada has already introduced legislation to ban BPA in children’s products, while California lawmakers announced last week that they were considering legislation that would ban BPA in containers designed to be used by children under three years of age.