Dangerous levels of the toxic chemical bisphenol A are present in many infant formulas, according to a new report from the nonprofit Environmental Working Group. The chemical leaches into formula because it is used to line product cans, the report said.

In 2007, the EWG also reported that BPA in package linings of canned foods and in plastic baby bottles can migrate into food and beverages, but the current findings pose a more urgent health threat, according to Sonya Lunder, a senior analyst for EWG in Washington, D.C. "Because infants eat so much more than adults per pound of body weight, [those on formula] are getting doses of BPA that surpass that of lab animals who displayed toxic effects such as aggression," she said.

"Given what we know, about one in every 16 infants fed liquid canned formula would be receiving the levels that significantly changed testosterone levels in lab animals."

BPA has been shown to increase cancer-cell growth and affect hormone systems that guide much of the permanent development of infants' breasts and prostates, according to the EWG. Research demonstrates that it also affects the activity of more than 200 genes, Lunder said.

The International Formula Council dismissed EWG's report and stated that the levels of BPA the EWG detected were far below those approved by government safety authorities. But Lunder said those safety limits were defined a decade ago, and research since has called those levels into question.

According to the EWG, all manufacturers of infant formula use BPA as the coating for their cans. "It's an industry standard, even with naturals, because [the cans] are recyclable," Lunder said.

EWG offers suggestions to retailers who encounter customers concerned with the recent findings:

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