Abstract - A method for an unbiased search for volatile organics is described. It is based on direct headspace extraction, capillary GC separation on an apolar stationary phase and ion-trap detection. By automatic reconstruction of the chromatogram with each ion in the scanned mass range (29-199 u), peaks that did not appear on the total ion chromatogram could be spotted. The concentration of some organics at the limit of detection was in the range 0.03-8 µmol/l in blood. Owing to the high sensitivity, the mass spectrum of a peak was not reliable as the sole proof of a substance present at a low concentration. The identification was therefore made on the basis of joint data from mass spectra, searched on-line in a library, and retention indices, retrieved from the literature. To show the value of the method, examples are given of some scarce intoxicants found in post-mortem samples.
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