Foreigners are introducing Israeli youngsters to drugs, the chief pharmacist of the Tel Aviv Health Office charged today. Abraham Tornau, addressing the closing session of the second Congress of the World Alliance for Israeli Pharmacy, blamed the influx of volunteers and tourists from abroad for the rising incidence of drug abuse among minors.

He said the youngest recorded user was a nine-year-old boy who was persuaded to smoke hashish, a form of marijuana by a 13-year-old friend. Tornau said that 182 minors were among the 892 persons arrested for using hashish in 1971. He said 40 percent of the users arrested were foreign tourists including 178 Americans.

Tornau said that 40,000 Israelis are thought to be habitual users of hashish, opium, LSD and other drugs, though heroin, a powerful opium derivative, is not widely used in this country. He reported that police hauls of hashish dropped drastically last year.