WASHINGTON, Sept. 10 (UPI) –– Henry L. Giordano, Assistant Narcotics Commissioner, said tonight his agency had counted 44,146 narcotics addicts in the United States. He said 60 per cent of them were between 21 and 30 years old. Mr. Giordano, who spoke on a Mutual Broadcasting System radio program, reported that a majority of the addicts were men and that 12 per cent of the total were under 21.