AUGUSTA – A legislative committee unanimously recommended Wednesday that a brochure be created for dentist’s offices to warn about possible health risks of fillings containing mercury.

Members of the Natural Resources Committee supported the bill after hearing from state experts that scientific studies show that the fillings contribute to a person’s mercury exposure even though there’s no conclusive evidence that the fillings cause harm. The bill, which still must be passed by the Legislature, directs the Bureau of Health to develop the brochure.

“In many ways we are taking a giant step forward compared to what’s been done across the country,” said Sen. John Martin, D-Eagle Lake.

Frances Miliano, executive director of the Maine Dental Association, said the group would support the effort to have a brochure available for distribution. The MDA wants the brochure to be based on reputable science, and it wouldn’t mind including disclosure of the risks of other filling materials, she said.

Some types of mercury, in high enough concentrations, have been shown to be harmful to the nervous system. It’s particularly harmful to the young, whose systems are still developing.

At Wednesday’s session, Dr. Andrew E. Smith, state toxicologist, said studies about the risks from the type of mercury in fillings haven’t been conclusive. There have been contradictory results, and the size of the studies have been too small to be definitive, he said.

In an interview after the session, Smith said studies scheduled to be finished in the next two to three years should provide much better scientific footing to decide how serious the health threat is from fillings containing mercury.

Doing some rough calculations, Smith said that consuming one 6-ounce can of tuna per week equals the amount of mercury vapor ingested weekly by a person with several fillings containing mercury. The vapor is absorbed by the body even more readily than if a person swallowed mercury from a thermometer, he said during the hearing.

Because scientific investigators don’t agree on the dangers of the type of mercury in fillings, there is much uncertainty, he said.

Smith helped develop state recommendations on the number of meals of freshwater fish caught in Maine that people should consume. Warm-water fish such as pickerel and bass contain more mercury pound for pound than cold-water fish such as trout and salmon. The recommendations also call for fewer meals of fish caught in Maine’s fresh waters for women of childbearing years and children.

Dr. Dora A. Mills, director of the Bureau of Health, said with the scientific uncertainty, the bureau would not support banning mercury from fillings in Maine. But she said the bureau supports the idea of a brochure, which likely would be more effective than requiring a poster on the walls of dental offices describing potential dangers of the fillings.

A brochure, she said, could be crafted in a way to be understandable to the general public and would allow more space for an explanation of the risks and benefits of certain types of fillings, she said.

A couple of committee members, who quoted from studies they had highlighted, said the bureau and committee should go further in educating and protecting Mainers about the possible risks.

“I’m concerned it does not go far enough,” said Rep. Joanne Twomey, D-Biddeford. She said she wants to at least protect pregnant women and young children, and she scolded Mills for not doing enough to protect the public from fillings.

She said that after reading the medical research about the possible dangers of mercury in fillings, in the future she would pay close attention to her grandchildren’s dental work.

“When it comes time, I’m convinced you’re not going to put [mercury] in their mouths,” Twomey said.

“I am overwhelmed with the stories and the experiences that have come to us from basically around the world and from right here in Maine,” said Rep. Christina Baker, D-Bangor.

Twomey persuaded the committee to listen to Shannon Johnson of Harpswell, even though the public hearing was held the week before.

Johnson told the committee that her son has autism that she believes is linked to transmission of mercury from her fillings to him while he breast-fed.

“I would never have put mercury in my mouth [had I known],” she said.

Smith said after the meeting that he is unaware of any link between mercury fillings and autism.

Sen. Martin said that just as cancer and cigarettes weren’t readily linked, mercury fillings and health problems long went undiscussed.

“When I asked my dentist a number of years ago what my fillings were, he said silver,” said Martin. “I never heard the word mercury.”

Martin said he expects dentists soon will voluntarily raise more details about the potential dangers of filling materials, if only to minimize legal challenges in the future.