ROCKVILLE, Md.  A hormone-like chemical should be taken out of food packaging, especially baby bottles, infant formula cans and other products used by children and pregnant women, university researchers and consumer advocates told a Food and Drug Administration subcommittee Tuesday.

The FDA has said that the chemical, bisphenol A, or BPA, doesn't pose a risk at the levels to which people are commonly exposed. BPA has been detected in the bodies of virtually all Americans tested.

But critics questioned why the FDA based that ruling on three studies funded by the chemical industry, all of which found BPA to be safe at current exposure levels. Hundreds of independent studies in animals and cells suggest the estrogen-like chemical poses serious risks.

The newest research — the first large study in humans — links BPA to both heart disease and diabetes in adults. Adults with the highest BPA levels in their urine were more than twice as likely to have heart disease or diabetes than those with the lowest levels, according to the study of 1,455 people, published online Tuesday in The Journal of the American Medical Association. The total number of people with these conditions was small: 79 had heart disease and 136 had diabetes.

In a letter sent to the FDA Tuesday, Sen. Charles Grassley, R-Iowa, Tuesday became the latest lawmaker to ask the agency FDA why it gave preference to industry-funded studies. Grassley — who noted that much of the research rejected by the FDA was paid for by the National Institutes of Health — asked the FDA to provide copies of all communication with the American Chemistry Council, which funded one of the pivotal studies cited by the FDA.

FDA scientist Laura Tarantino said the agency relied on industry studies because they were very large and included raw data, which allows the FDA to independently verify the findings.

But Frederick vom Saal, a University of Missouri professor, says the industry studies' flaws make them useless in deciding on a safe exposure level for BPA. "The FDA is ignoring all of this research," vom Saal says. "While it has been doing that, Americans have been at risk."

The FDA's report puts it at odds with the National Toxicology Program, which this month expressed "some concern" that BPA alters the brain, behavior and prostate in fetuses and children. That study included many studies that were not weighed in the FDA safety standard. Babies are mainly exposed to BPA through liquid infant formula, which is usually sold in metal cans lined with the chemical, as well as bottles made of polycarbonate plastic, according to the FDA report. Powdered formula probably is much less contaminated with BPA. John Bucher, the toxicology program's associate director, says this put formula-fed infants most at risk.

HOUSE DIVIDED: How federal agencies can disagree on BPA

D. Gail McCarver, a pediatrician at the Medical College of Wisconsin, says the FDA report underestimates how much BPA children are exposed to. She notes that the report's safety ruling is based on "average" exposures for formula-fed infants — even though some babies may consume much more than average. "I do not believe we should be protecting our children at an average level," McCarver says.

Consumer activists have warned about the dangers of BPA for a decade. Now that research also finds disease in humans, activists say the FDA needs to revise its ruling that the chemical is safe in everyday use.

At the very least, the FDA should require a prominent warning on products made with BPA, says Diana Zuckerman, president of the National Research Center for Women & Families. Products made with BPA today are rarely labeled, making it difficult for consumers to avoid them.

The FDA received about 200 public comments on its draft report. About 20 people — most opposed to the use of BPA — spoke at the hearing. Sonya Lunder of the Environmental Working Group says it's especially important to protect fetuses and infants from BPA, because they are the most vulnerable to hormonal influences. Yet she says babies are exposed to more than 12 times as much BPA per pound of body weight as adults.

McCarver says there's a critical need to measure BPA exposure in babies, especially premature infants, who are exposed to many plastic medical devices and tubes while in the hospital.

But McCarver says she doesn't support completely banning BPA, which is used to make life-saving bicycle helmets. If manufacturers replace it with another chemical, she says, there should be thorough tests to make sure the replacement is safe.

GET ANSWERS: Have questions about how to avoid BPA? Health reporter Liz Szabo joins the conversation to answer your questions below.