A gas sampling system includes a sample trapping module having a gas pump and a power supply, and a removable magazine that fits within a port of the trapping module. The magazine contains a non-volatile electronic memory, which controls operation of the trapping module, and has a rotating carousel for holding sample tubes. Individual sample tubes are sealed at each end by a cap that has a needle-pierceable septum, and contain a solid collector material to trap chemical and biological contaminants in a gas sample drawn through the sample tube. Individual sample tubes are moved into and out of a sampling location by incremental rotation of the carousel and, while at the sampling location, a pair of hollow bore needles are inserted through the sample tube end caps to allow the drawing of a gas sample through the tube.