A Dartmouth College scientist whose specialty was the dangers of heavy metals died of mercury poisoning this week, 10 months after as little as a drop of a rare toxic compound apparently seeped through her rubber gloves.

Karen Wetterhahn, 48, had been hospitalized since January, when tests showed 80 times the lethal dose of mercury in her blood, a college investigation showed.

After she was diagnosed Jan. 28, Wetterhahn told investigators she remembered spilling one to several drops of dimethylmercury in August, chemistry department chairman John S. Winn said yesterday.

Three weeks after she was diagnosed, she went into a coma that lasted until her death Sunday at Dartmouth-Hitchcock Medical Center in Lebanon.

Wetterhahn, a cancer researcher, was using the compound to examine the effects of toxic metals on human cells.

At the time of the accident, she was studying how mercury prevents cells from repairing themselves, much like cancer does.

Mercury attacks the central nervous system well before the victim shows symptoms, and Wetterhahn began losing her balance and having trouble speaking and hearing in January, five months after the spill in the lab, Winn said.

Tests by an independent laboratory after the spill showed that the rare compound, first synthesized in 1841, can pass through rubber latex gloves quickly, usually without damaging them, Winn said.

In a letter published last month in the newsletter of the American Chemical Society, Dartmouth officials urged anyone working with the compound to wear neoprene gloves with long cuffs and to have their blood and urine tested frequently.

The U.S. Occupational Safety and Health Administration also is investigating and will have a report by October.

A Dartmouth faculty member for 21 years, Wetterhahn had been dean of graduate studies and associate dean of the science faculty and was recognized internationally in her field, Winn said.