Marijuana cigarettes laced with cocaine and other hard drugs may be circulating around Harvard and other area schools unbeknownst to potential users, University Health Services (UHS) warned yesterday in an e-mail sent largely to first-years.

“There seems to be marijuana laced without students’ knowledge,” said UHS Director David S. Rosenthal ’59. “We issued the advisory to make students aware of the problem, aware of the danger of cocaine.”

The e-mail advised that smoking marijuana laced with other drugs can prove dangerous and even fatal.

Rosenthal said that he decided to send an e-mail warning about the possibility of tainted marijuana after conferring with health officials from across the Boston area.

He also said that students from both Harvard and other area campuses informed health officials of the risk.

Though Rosenthal said Harvard students helped bring the issue to light, there have yet to be any reports of students coming to UHS after smoking contaminated marijuana.

“But we don’t want the first instance to be the tragic one,” Rosenthal said.

“For this reason,” the e-mail stated, “students are strongly advised to avoid the use of all illegal substances.”

Rosenthal said he sent the advisory to Dean of Freshmen Elizabeth Studley “Ibby” Nathans, who then forwarded the e-mail to freshmen proctors.

First-year students, Rosenthal speculated, are particularly concerned about drugs on campus, which explains giving them top priority.

“Freshmen this year seem surprised by drug practices on campus,” he said.

Upper-class students did not receive the e-mail advisory.

The Massachusetts Department of Public Health also recently disseminated its own warning about increased cocaine use among local college students.

Though UHS does not have statistics on cocaine use on campus, Rosenthal said he is generally concerned by what appears to be an increase in drug and alcohol abuse at Harvard this year.

In September and October of this school year, UHS admitted 12 and 15 students, respectively, for alcohol-related reasons.

Those figures represent a 50 percent increase over the totals seen in the first two months of the 2000-01 academic year.

In fact, the total of 27 cases is already five more than the 18 cases UHS saw in 1998.

“We are troubled by increased alcohol and drugs on campus,” Rosenthal said. The laced marijuana, he said, was merely a reflection of what seem to be larger trends at Harvard and throughout the Boston area.

—Staff writer Alexander B. Ginsberg can be reached at ginsberg@fas.harvard.edu.