In response to a student request, the professor in charge of laboratories in Chemistry 20, "Organic Chemistry," has begun to look for replacements for several carcinogenic chemicals now used by students in experiments required for the course.

David J. Monroe '78 said yesterday he asked James D. Wuest, assistant professor of Chemistry, to discontinue experiments involving dioxane, chloroform, carbon tetrachloride and benzene which are known to produce cancer in laboratory animals.

Monroe said a poll he conducted among Chem 20 students showed that less than one-third knew about the carcinogenic effects of the chemicals.

He asked Wuest to remove the chemicals from the lab, to label dangerous chemicals remaining in use and to warn students more forcefully about possible hazards, he added.

Wuest said yesterday it made sense to remove the chemicals even if they did not pose a very serious hazard. He added that he will try to replace the chemicals by the summer term, and that he hopes the change will be permanent.

The change is not at all revolutionary, Wuest said, but it will take some time to revise the experiments in the lab manual.

Jeffrey Hayes, a teaching fellow in Chem 20, said yesterday he doubts that the hazardous chemicals can be replaced. "Almost anything is carcinogenic in sufficient concentration," he said, adding that chemicals like benzene are essential to chemistry.

"It is perfectly possible to replace chemicals like benzene in an elementary course such as Chem 20," William V. Doering, Mallinckrodt Professor of Chemistry, said yesterday.

The department has always been aware of the dangers of the chemicals in question, Doering said, adding that he has "great sympathy with the proposed changes."