Internally concealed cocaine: analytical and diagnostic aspects.

Thirty persons arrested at Frankfurt airport for smuggling internally concealed cocaine in 1993/1994 were investigated. An X-ray examination (in all 30 cases), immunochemical examination of urine (in 27 cases) and of saliva (in 20 cases) was performed in parallel. An X-ray examination gave positive results in all examined persons. EMIT cocaine metabolite assay (cut off 300 ng benzoylecgonine (BE)/mL) was positive in eight urine samples. After reducing the cut off to 150 ng BE/mL urine, eleven samples were classified as positive. The results were confirmed by means of chromatographic determinations. These findings showed limited role of immunological examination of urine as a screening test in suspected smuggling of internally concealed drugs. All saliva samples showed negative immunochemical results. The number of concealed containers ranged from 44 to 135 per person. The amount of cocaine hydrochloride found in particular cases ranged from 242 to 1050 g net weight, divided into containers weighing from 5.7 to 13.8 g. Drug packages were obviously machine-made. The packages smuggled by a particular person were uniform. However, a distinct interpersonal variability in drug packages was observed, in regard to the number of protective layers (4-7), size, weight, and cocaine purity. This may be helpful for the identification of production site. The leaching of cocaine from selected containers was investigated in a stirring bath and was independent of the conditions applied.