When Gregory Tucci, assistant instructional laboratory coordinator in the chemistry department, spoke to Cambridge firefighters about handling hazardous materials in early October, he didn't anticipate having to give a hands-on demonstration.

But during the lecture, a toxic chemical spill at Mallinckrodt Chemical Laboratory set off a small fire, forcing the Cambridge Fire Department (CFD) to mobilize in the middle of Tucci's talk.

A student had broken a bottle of tetrahydrofuran (THF), a highly flammable solvent, and a nearby electric stove ignited the THF fumes.

"The spill happened while I was there [giving that lecture]," Tucci says. "That's hysterical."

The spill is part of a recent spate of lab-related accidents. The Mallinckrodt spill was one of three spills to occur in the past six weeks and one of four in the past six months.

The recent rash of laboratory accidents prompts questions about safety measures and precautions in Harvard's laboratories. Despite the spills, students and faculty say they continue to feel safe when they work in lab.

SPILL AFTER SPILL

The first major lab-related accident this year occurred in May, when three post-doctoral fellows triggered an explosion while compiling an inventory of laboratory chemicals.

The researchers were cleaning up an infrequently-used chemical storage area in an attic of the Converse Chemical Laboratories. One researcher turned around a two-liter glass bottle of isopropyl chloroformate, an eye and skin irritant, to identify it. Moments later, the bottle burst.

The explosion sprayed the chemical and the toluene in which it had been stored in the face of the researcher who handled the bottle. The chemical also touched the clothing of the other two researchers. All three were rushed to Massachusetts General Hospital, where they received treatment for minor injuries.

David A. Evans, Abbott and James Lawrence professor of chemistry, heads the laboratory. According to Evans, the chemical in the bottle should have been stored in a refrigerator, but the label did not specify the temperature of storage. As a result, the chemical was stashed away and, as it decomposed, liberated carbon dioxide built up pressure in the bottle.

"It was a really hard situation to avoid because we work with such potentially hazardous materials," Evans says. "Part of the blame lies in the oversight of the manufacturer of the chemical, who neglected to note that the chemical needed to be stored at zero degrees Celsius. The accident resulted from a lack of understanding, both on the part of the supplier and the student."

On October 20, two weeks after the Mallinckrodt spill, another spill forced complete evacuation of Harvard Medical School's Seely G. Mudd Building. A faulty refrigerator shelf broke, causing bottles to break and chemicals to mix. The seven people in the building at the time left uninjured.

A phosphorous acid spill in the Lyman Physics Laboratories followed a week later, requiring the evacuation of the Lyman, Jefferson and Cruft laboratories. The chemical was leaking from a container in the basement machine shop of Lyman.

CFD and the hazardous waste response team, a unit of CFD, contained the spill within an hour and a half.