People trust dentists with their health. Some members of Congress are more skeptical.

The dental industry, asked to testify Tuesday about pollution from mercury in tooth fillings, found itself under attack from lawmakers who blame mercury for everything from autism in children to skin discoloration.

The hearing was about whether dentists should be required to install "separator" equipment to keep pieces of fillings from getting into public wastewater. Currently, dentists in nine states are required to use separators.

The American Dental Association, before its spokesman testified, faced deeply personal diatribes from Reps. Dan Burton, R-Ind., and Diane E. Watson, D-Calif.

Burton began by saying he'd had a cap replaced, and a silver filling removed, over the weekend, and that he worried as he swished the water in his dentist's office about where his filling would go.

Then Burton talked about his grandson, saying the child became autistic not long after receiving nine vaccination shots, seven of them containing mercury. While such theories have been rejected in mainstream medicine, Burton has held several hearings on it in the past. Mercury has not been in childhood vaccines since 2001.

"Mercury should not be ingested into the human body in any way," he said.

Watson had her own issues. She blamed mercury fillings she got as a 9-year-old for allergies, headaches, darker and splotchy skin and trouble remembering people's names. She talked to researchers who thought she had mercury poisoning.

"I had to go to Mexico _ I asked my own dentist about it, and he stuffed something in my mouth and wouldn't even discuss it," Watson said. Continued...