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This study was carried out to characterize the ambient VOCs concentrations of industrial complex in Daegu city. VOCs concentrations of industrial complex area appeared to be higher than those in the non-industrial complex area as following order toluene > ethylbenzene > m,p-xylenes > o-xylene but benzene and chloroform were similar to each other sites. There was seasonal variation of VOCs concentrations in the industrial complex area, higher in summer and lower in winter. In particular the industrial complex area shows that higher on weekday than weekend and higher in the daytime than in the morning or nighttime because industrial complex area influenced by the chemicals. Correlation coefficients among VOCs were confirmed that VOCs of industrial complex area were more related to each other than those of non-industrial complex area and VOCs concentrations have shown generally negative correlation with wind speed.

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To ensure the safety of the citizens of Daegu with respect to drinking water sources, we continuously monitored trace pollutants in the Nakdong River basin. Perfluorinated compounds (PFCs) had been detected in the Nakdong River previously; thus, further low-concentration detection is required. We developed an LC-MS/MS analysis method using the online SPE approach for fast and simple detection of low-concentration PFCs. In this process, a delay column was used to assess PFC contamination. As a result, quality control analysis of eight standard PFCs using this method showed strong correlations, with correlation coefficients of 0.991 and more, and the limit of quantification was 0.5 to 1.7 ng/L. The recovery rates of PFCs from samples ranged from 75.3% ± 1.23% to 118.0% ± 1.39%, suggesting robustness of this method. Analyses of PFC at seven sampling points in the Nakdong River basin showed high PFC concentrations at the point where effluent from a sewage treatment plant was introduced. PFHxS, PFOA, and PFOS values, which were used as drinking water monitoring standards of treated water at the Daegu advanced water treatment plant, did not exceed the monitoring standards. Therefore, these results demonstrate that the established method is appropriate as an analytical tool for assessing low-concentration PFCs in drinking water.

No abstract