Determination of VOCs in Indoor Air Using Passive Sampling?Thermal Desorption?GC/MS and Simultaneous Survey of Indoor VOCs in Sapporo City in Winter

We investigated a passive sampling-thermal desorption-GC/MS system, which is a simple sampling method and a highly sensitive analytical method, for the determination of volatile organic compounds （VOCs） in indoor air. Diffusive uptake rates of 9 compounds, carbon tetrachloride, trichloroethylene, toluene, tetrachloroethylene, ethylbenzene, m, p-xylene, o-xylene, styrene and p-dichlorobenzene, were calculated on the basis of the results of simultaneous mea-surement by passive and active sampler indoors and outdoors. Relative standard deviation（RSD） of diffusive uptake rates for these compounds were under 20％ except ethylbenzene, whose RSD was 27.7％. These results showed the passive sampling-thermal desorption-GC/MS system can be applied to the determination of VOCs in indoor air. This method was applied to investigate the indoor VOC levels in Sapporo city in winter. Nine kinds of VOCs in indoor air were measured at 34 houses in Sapporo at the same time （February 14, 1996）. Indoor concentrations of VOCs except carbon tetrachloride were higher than those of outdoor air, which suggested that the emission source was in the house. The concentrations of toluene, ethylbenzene, o-xylene and m, p-xylene were significantly higher in newly built house and renovated house. These compounds were used as solvent in paints and adhesives for building materials