Oct. 28 (Bloomberg) -- Allegations of conflicts of interest related to a University of Michigan researcher are clouding a U.S. advisory panel's review of the safety of bisphenol A, a chemical used in plastic.

In letters to the agency, lawmakers have criticized ties between one of the Food and Drug Administration's advisers, Martin Philbert of Michigan, and supporters of the chemical. Representative Rosa DeLauro, a Connecticut Democrat, said in a letter being released today, that an Oct. 31 advisory panel meeting should be canceled, partly because of Philbert's ties to industry.

Lawmakers have repeatedly questioned the FDA's oversight of Bisphenol A, or BPA, which has been used for decades to help stiffen plastic for baby bottles and food-storage containers and to line metal cans. A draft FDA staff report from August said BPA is safe at current exposure levels. BPA has been linked in some studies to diabetes and developmental changes in children.

``There appears to be a complete undermining of the decision-making process at FDA on the BPA issue and I fear that this case demonstrates that the conflict of interest standards governing scientific advisory panels are inadequate,'' DeLauro said in the letter to Andrew von Eschenbach, the FDA commissioner.

DeLauro's letter cited connections between Philbert, a founder and acting director of the Risk Science Center at the University of Michigan in Ann Arbor, and the BPA industry. As the leader of a subcommittee of the agency's Science Board, Philbert has been preparing a report reviewing the FDA's assessment of BPA. The full panel is to meet Oct. 31 to discuss the report.

Grants From Dow

The risk center received grants totaling $15 million from Dow Chemical Co., a manufacturer of BPA, DeLauro said, citing an article written by Philbert. The grants funded a study examining dioxin, a toxic compound, in an area near a Dow plant in Michigan.

The study found that people living in counties near the plant ``had higher levels of dioxins in their bodies than a control group of people elsewhere in Michigan,'' Philbert wrote in an Oct. 21 article in the Milwaukee Journal Sentinel. ``These are the kinds of high-stakes questions that the risk center seeks to answer, basing those answers exclusively on rigorous science.''

`Best Scientific Analysis'

The center's mission ``is to provide the best scientific analysis with the highest standards of independence and integrity,'' Philbert wrote.

Philbert didn't return a telephone call yesterday. Kelly Cunningham, a university spokeswoman, said she didn't have an immediate comment. Michael Herndon, an FDA spokesman, declined to comment, saying the agency will respond directly to DeLauro.

David Winder, a spokesman for Midland, Michigan-based Dow, said in a telephone interview yesterday that the company's funding went to the university and he wasn't certain whether the study was completed by researchers associated with the risk center.

Earlier this month, Representatives John Dingell and Bart Stupak, Democrats of Michigan, sent a letter to von Eschenbach questioning a $5 million donation Philbert's center received from a retired medical-equipment manufacturer. The equipment manufacturer has said BPA is safe and has shared his opinion with Philbert, the lawmakers said in an Oct. 15 statement.

Separately, DeLauro said the FDA hired a private consulting company with ``strong industry ties'' to complete some analyses of the chemical. DeLauro heads a House subcommittee that oversees FDA funding.

An estimated 93 percent of Americans have traces of bisphenol A in their urine, according to the Centers for Disease Control and Prevention, a U.S. agency in Atlanta. The chemical was declared ``toxic'' by the Canadian government in April.

BPA-Free Products

The American Chemistry Council, an industry group, says ``trace levels'' in consumer products don't pose a risk. Still, Energizer Holdings Inc.'s Playtex Infant Care unit and Thermo Fisher Scientific Inc., the maker of Nalgene sports bottles, have stopped using BPA in their new products.

Adults exposed to higher levels of BPA are twice as likely to develop cardiovascular disease or diabetes, according to a study in the Journal of the American Medical Association last month.

Animal studies reviewed by the U.S. government's National Toxicology Program this year also linked the chemical to developmental changes in fetuses and young children. The group, which is part of the Health and Human Services Department, ranked the risk level for children in the middle of a five-point scale.

To contact the reporter on this story: Justin Blum in Washington at jblum4@bloomberg.net.

Last Updated: October 28, 2008 00:01 EDT