Chemical trace detection system

Desorber 600 has body 610 which can be removably coupled to a sample inlet of a chemical trace detection system. Sample heater 640 can desorb a sample held in sample trap 630 coupled to sample holder 620, which is connected to the body. A desorber attachment feature may mate to a tube attachment feature of the system. The desorber may include a fluid flow channel with openings to the exterior, may have cooling means, and may have a gripping region (611B, Fig. 6B) for a user. In a chemical trace detection system (e.g. ion mobility spectrometer 300, Fig. 8A), a voltage source produces an electric field in drift tube 310, and an ioniser establishes an ionisation region (321, Fig. 8A). Inserting the desorber into the inlet (321, Fig. 8A) places the sample in or adjacent to the ionisation region. Sample is desorbed directly into the ionisation region, and forced towards a detector by the electric field.