The majority (82.3 percent) of all cases examined by the Division of Narcotic Drugs Research Laboratories of the Council of Forensic Medicine of Turkey, related to Cannabis products. Heroin represented 16.7 percent and all other controlled drugs made up the remaining 1 percent. From the 691 samples analyzed, 43.15 percent was Cannabis plant material. From the 140 illicit heroin samples analyzed by capillary gas chromatography, 61 percent had a diacetylmorphine content between 30 and 48 percent. 0-6-monoacetylmorphine was detected in 43 percent of the samples ranging from 0.4 to 8.6 percent. Almost half (46.6 percent) of all heroin samples contained procaine ranging from 0.7 to 22 percent. (Author abstract)