| Summary: | 碩士 === 國立屏東科技大學 === 環境工程與科學系 === 94 === Levels of Methyl tert-Butyl Ether (MTBE), benzene, toluene, ethylbenzene and the xylenes (BTEX) in different indoor microenvironments such as offices, homes and schools were investigated in southern Taiwan. Different indoor environments including three offices, three homes, and two school were selected in southern Taiwan for indoor and outdoor MTBE and BTEX measurement. Charcoal tubes (ORBO-32,100 mg/50 mg) were used to collect air stream, and the GC/FID technique was applied to quantify the concentrations of both MTBE and BTEX. In addition, this study also investigated the MTBE and BTEX levels in the different vertical highes at Kaohsiung city volatile organic compounds (VOCs) samples was samping by the canisters in the fields GC/MS analysis method (TO-15) was applied for the ambient VOC investigations.
The results showed that the toluene has the highest concentration in three species. In addition, comparing the indoor air quality, the concentration of the office type is the highest, and school type has the lowest concentration. We determined the pollution source with the ratio of the concentration indoor to outdoor, and used principal component analysis to reduce the variables in this study. In aspect of health risk accessment, at site B, is higher than that of acceptable value (1×10-6). In non-cancer risks, the total damage index of sampling site B is higher than 1, others are below.
In different sampling height, we analyzed the total volatile organic compounds (TVOCs) concentration in four sampling periods T07-09, T12-14, T17-19 and T23-01. The concentration ratios as follows:
(i). T07-09, H0M：H13M：H32M：H58M：H110M＝1：0.61：0.67：0.46：0.41；
(ii). T12-14, H0M: H13M：H32M：H58M：H110M＝1：0.78：0.57：0.15：0.10；
(iii). T17-19, H0M : H13M：H32M：H58M：H110M＝1：0.89：0.57：0.41：0.27；
(iv). T23-01, H0M : H13M：H32M：H58M：H110M＝1：1.31：0.71：0.29：0.07.
These ratios revealed that the TVOCs concentrations decrease when the heights increase. Comparing the different sampling durations, all altitudes of TVOCs concentrations in period T07-09 are higher than other periods (which are 272ppbv, 165ppbv, 183ppbv, 125ppbv and 112ppbv for H0M, H13M, H32M, H58M, H110M, respectively). There results were associated withfact of traffic reasons. Moreover, employee arrive the companies in the same time, so the traffic is also high and resulted in the high. However, T17-19 is different from T07-09. The commution time of come off work is longer and more inconstant. So the traffic is high but not concentrated comparing with go to work. Besides, this phenomenon in T12-14 and T23-01 are not obvious. It could be the fact that of the photochemical reation is stong at noon in atmosphere, and the traffic pollutants were less.
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