The concentration levels of total iodine obtained by RNAA in different sorts of tobacco, including the reference sample Kentucky Tobacco 2RI, two new candidate reference materials, Oriental Tobacco Leaves /CTA-OTL-1/ and Virginia Tobacco Leaves /CTA-VTL-2/ prepared in the Institute of Nuclear Chemistry and Technology, Warsaw, and some biological SRMs, are presented and discussed. © 1990 Akadémiai Kiadó.