## 3 Results
### Long-Distance Transport Using VOCs
Table 4 and Figure 7 show relationships between Cf/NaT, 12 Dice/NaT, TCCE/NaT, and CB/NaT and CO, eBC, EC, OC, WSOC, NH\({}_{4}^{+}\), NO\({}_{3}^{-}\), and PM\({}_{2.5}\) during the event period. As indicated in the table, r\({}^{2}\) for Cf/NaT, 12 Dice/NaT, TCCE/NaT, and CB/NaT were 0.170, 0.783, 0.507, and 0.568, respectively. This means that Cf/NaT had no relationship with long-range transport. However, TCCE/NaT and CB/NaT were partially related to \begin{table}
\begin{tabular}{c c c c c c} \hline \hline
**Compound (\({}^{\text{1}}\))** & **Overall Average** & **LRT (\({}^{\text{2}}\)) Periods** & **Other Periods** & **Ratio (\({}^{\text{3}}\))** & **Non Event** \\  & & & & & **STD (\({}^{\text{4}}\))** \\ \hline Acrylonitrile & 0.021 & 0.016 & 0.022 & 0.727 & 0.029 \\
1,1-Dichloroethane & 0.234 & 0.266 & 0.221 & 1.204 & 0.289 \\ Chloroform & 0.045 & 0.075 & 0.039 & 1.923 & 0.041 \\
1,2-Dichloroethane & 0.044 & 0.116 & 0.031 & 3.742 & 0.025 \\ Benzene & 0.729 & 0.483 & 0.781 & 0.618 & 0.782 \\ Carbon tetrachloride & 0.048 & 0.044 & 0.049 & 0.898 & 0.018 \\ Trichoroethene & 0.007 & 0.004 & 0.008 & 0.500 & 0.017 \\ Toluene & 0.986 & 0.677 & 1.052 & 0.644 & 1.699 \\ Tetrachloroethene & 0.006 & 0.010 & 0.006 & 1.667 & 0.007 \\ Chlorobenzene & 0.007 & 0.012 & 0.006 & 2.000 & 0.012 \\ Ethylbenzene & 0.100 & 0.098 & 0.101 & 0.970 & 0.166 \\ m\&p-Xylene & 0.040 & 0.042 & 0.040 & 1.050 & 0.079 \\ Styrene & 0.080 & 0.060 & 0.084 & 0.714 & 0.057 \\ \(\alpha\)-Xylene & 0.047 & 0.045 & 0.047 & 0.957 & 0.078 \\ Bromobenzene & 0.051 & 0.035 & 0.053 & 0.660 & 0.067 \\ Isopropylbenzene & 0.007 & 0.007 & 0.007 & 1.000 & 0.006 \\
2-Chlorotoluene & 0.002 & 0.001 & 0.002 & 0.500 & 0.004 \\
1,3,5-Trimethylbenzene & 0.004 & 0.003 & 0.004 & 0.750 & 0.004 \\ p-Isopropylbenzene & 0.010 & 0.011 & 0.009 & 1.222 & 0.010 \\
1,2,4-Trimethylbenzene & 0.017 & 0.018 & 0.017 & 1.059 & 0.007 \\
1,2-Dichlorobenzene & 0.004 & 0.004 & 0.004 & 1.000 & 0.002 \\
1,3-Dichlorobenzene & 0.001 & 0.001 & - & - & 0.002 \\ tert-Butylbenzene & 0.001 & - & 0.001 & - & 0.002 \\
1,4-DiChlorobenzene & - & 0.001 & - & - & 0.001 \\ n-Butylbenzene & 0.007 & 0.007 & 0.007 & 1.000 & 0.003 \\ Naphthalene & 0.090 & 0.082 & 0.091 & 0.901 & 0.014 \\ \(\Sigma\)VOCs & 2.588 & 2.118 & 2.682 & & \\ \hline \hline \end{tabular} \({}^{\text{(a)}}\) Unit: ppb; \({}^{\text{(a)}}\) long-range transport; \({}^{\text{(b)}}\) ratio of long-range transport to other periods; \({}^{\text{(a)}}\) standard deviation.  
\end{table} 
Table 3: VOCs concentrations measured during the study period. long-range transport. Meanwhile, 12 Dice/NaT presented a high correlation with long-range transport. Thus, 12 Dice can be used as an indicator for long-range transport. Because the r\({}^{2}\) of CO and 12 Dice/NaT, as a direct index for long-range transport, was higher than 0.9, 12 Dice/NaT can be used as an indicator for long-range transport with CO/CO\({}_{2}\). These results clarified the possibility of using VOCs as an indicator for long-range transport. It was confirmed that 12 Dice could be used as an evaluation index for long-range transport based on the overall results of VOC lifetime in the air, increases during event period, and correlations with other long-distance indices.