Optimization of method for extracting 46 volatile organic compounds (VOCs) from an activated carbon–silica gel active sampler to evaluate indoor work environments

The Industrial Safety and Health Act in Japan has established guideline values for volatile organic compounds (VOCs) in indoor workplace air; however, because the physicochemical properties of these VOCs are diverse, appropriate analytical methods have not yet been developed. Here we performed recovery tests to simultaneously measure VOCs and to optimize the analytical parameters (the extraction solvents and their mixture ratio) of a commercial activated carbon–silica gel active sampler. In the recovery tests, 46 VOCs were added to the adsorbents of the sampler (activated carbon and silica gel) at three concentration levels relative to the guideline values (0.5×, 1×, and 2×); we then extracted the VOCs from the absorbents by using various mixtures of acetone and carbon disulfide. The mixture comprising 80% acetone and 20% carbon disulfide was the best solvent overall for extracting the 46 tested VOCs from the adsorbents in the sampler; this mixture achieved adequate recovery rates (within the range of 80 to 120%) for 40 (87%) of the targeted VOCs.