CHICAGO (AP) -- Government researchers are pushing to test an unproven treatment on autistic children, a move some see as unethical.

The treatment is chelation (kee-LAY'-shun). It removes metals from the body and is based on the fringe theory that the mercury preservative once used in childhood vaccines triggers autism. That theory has been rejected by mainstream science.

Dr. Thomas Insel (IN'-sel) is the head of the National Institute of Mental Health. He supports testing chelation on children provided the tests are safe. He's heard from many parents who believe it works. For now, the study is on hold because of safety concerns.

Christina Blakey, a mother from Oak Park, uses chelation and a special diet with her 8-year-old son.

She applauds the government study. She says chelation has helped her son's autism symptoms.

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