Saper purchased 70 traditional Ayurvedic remedies at Boston-area South Asian grocery stores touted as cures for ills ranging from child colic to urinary tract infections and found 14 contained potentially toxic levels of mercury, lead and arsenic.

The report, published in the Journal of the American Medical Association, urged consumers of these products to get screened for heavy metal poisoning. It also renewed the American Medical Association's call for closer governmental monitoring of herbal remedies.

A few Ayurvedic products legally manufactured in India and Pakistan are herbs deliberately "cooked" with metals such as mercury, but any such product would be banned in the United States, said Michael McGuffin of the American Herbal Products Association, who was asked to respond to the journal article by Ayurvedic education groups.

"Mercury is an ingredient in traditional Ayurvedic formulas. They might be comfortable with it, my association is not," he said.

The tainted products purchased by the researchers would not be widely available, and customers were likely immigrants and others familiar with them, he said.

Ayurvedic products made in the United States and sold in many health food stores are free of such toxins, McGuffin said. Like most herbal remedies, they are benign and usually less powerful than prescription drugs, which he said do need close monitoring by the US Food and Drug Administration.