## 3 Results and Discussion
### PCDD/F and DL-PCB Concentrations
\begin{table}
\begin{tabular}{c c c c c c c c} \hline \hline \multicolumn{2}{c}{**Sampling Site**} & **TAT** & **HAC** & **USU** & **SAD** & **ISH** & **AOM** \\ \hline \multirow{8}{*}{PCDDs} & 2,3,7,8-TeCDD & \(<\)LOD & \(<\)LOD & \(<\)LOD & \(<\)LOD & \(<\)LOD & \(<\)LOD \\ \cline{2-8}  & 1,2,3,7,8-PeCDD & \(<\)LOD & \(<\)LOD & \(<\)LOD & \(<\)LOD & \(<\)LOD & \(<\)LOD \\ \cline{2-8}  & 1,2,3,4,7,8-HxCDD & \(<\)LOD & \(<\)LOD & \(<\)LOD & \(<\)LOD & \(<\)LOD \\ \cline{2-8}  & 1,2,3,6,7,8-HxCDD & \(<\)LOD & \(<\)LOD & \(<\)LOD & \(<\)LOD & \(<\)LOD \\ \cline{2-8}  & 1,2,3,7,8,9-HxCDD & \(<\)LOD & \(<\)LOD & \(<\)LOD & \(<\)LOD & \(<\)LOD \\ \cline{2-8}  & 1,2,3,4,6,7,8-HpCDD & \(<\)LOD & \(<\)LOD & \(<\)LOD & \(<\)LOD & \(<\)LOD \\ \cline{2-8}  & 0.CDD & \(<\)LOD & 6.9 & 1.5 & 8.0 & 3.7 & 0.66 \\ \hline \multirow{8}{*}{PCDD/Fs} & 2,3,7,8-TeCDF & \(<\)LOD & 1.5 & 0.41 & \(<\)LOD & \(<\)LOD & 0.22 \\ \cline{2-8}  & 1,2,3,7,8-PeCDF & \(<\)LOD & 1.2 & 0.39 & \(<\)LOD & \(<\)LOD & 0.30 \\ \cline{2-8}  & 2,3,4,7,8-PeCDF & \(<\)LOD & 1.1 & 0.50 & \(<\)LOD & \(<\)LOD & 0.26 \\ \cline{2-8}  & 1,2,3,4,7,8-HxCDF & \(<\)LOD & 0.79 & \(<\)LOD & \(<\)LOD & \(<\)LOD & \(<\)LOD \\ \cline{2-8}  & 1,2,3,6,7,8-HxCDF & \(<\)LOD & 0.83 & 0.23 & \(<\)LOD & \(<\)LOD & \(<\)LOD \\ \cline{2-8}  & 2,3,4,6,7,8-HxCDF & \(<\)LOD & 0.33 & 0.34 & \(<\)LOD & \(<\)LOD & \(<\)LOD \\ \cline{2-8}  & 1,2,3,7,8,9-HxCDF & \(<\)LOD & \(<\)LOD & \(<\)LOD & \(<\)LOD & \(<\)LOD \\ \cline{2-8}  & 1,2,3,4,6,7,8-HpCDF & \(<\)LOD & 0.55 & \(<\)LOD & \(<\)LOD & \(<\)LOD & \(<\)LOD \\ \cline{2-8}  & 1,2,3,4,7,8,9-HpCDF & \(<\)LOD & \(<\)LOD & \(<\)LOD & \(<\)LOD & \(<\)LOD \\ \cline{2-8}  & 0.CDF & \(<\)LOD & \(<\)LOD & \(<\)LOD & \(<\)LOD & \(<\)LOD & \(<\)LOD \\ \hline \multicolumn{2}{c}{Dioxins TEQ (pg-TEQ/g-dw)} & \(<\)LOD & 0.72 & 0.26 & 0.06 & 0.00 & 0.11 \\ \hline \multirow{8}{*}{non-_ortho_} & 3,4,4\({}^{\prime}\),5-TeCB(\#81) & \(<\)LOD & 31 & 16 & \(<\)LOD & 11 & 6.0 \\ \cline{2-8}  & 3,3\({}^{\prime}\),4,4\({}^{\prime}\)-TeCB(\#77) & 100 & 730 & 310 & 74 & 250 & 100 \\ \cline{2-8}  & 3,3\({}^{\prime}\),4,4\({}^{\prime}\),5-PeCB(\#126) & 18 & 110 & 47 & 14 & 40 & 21 \\ \cline{2-8}  & 3,3\({}^{\prime}\),4,4\({}^{\prime}\),5,5\({}^{\prime}\)-HxCB(\#169) & 3.3 & 13 & 7.7 & \(<\)LOD & 5.0 & 3.3 \\ \cline{2-8}  & 2\({}^{\prime}\),3,4,4\({}^{\prime}\),5-pentaCB(\#123) & 7.2 & 55 & 7.9 & 1.7 & 7.1 & 2.4 \\ \cline{2-8}  & 2,3\({}^{\prime}\),4,4\({}^{\prime}\),5-pentaCB(\#118) & 310 & 4500 & 740 & 170 & 570 & 260 \\ \cline{2-8}  & 2,3,4\({}^{\prime}\),5-pentaCB(\#114) & 7.2 & 120 & 26 & 56 & 17 & 7.2 \\ \cline{2-8}  & 2,3,3\({}^{\prime}\),4,4\({}^{\prime}\)-pentaCB(\#105) & 99 & 2200 & 350 & 64 & 230 & 140 \\ \cline{2-8}  & 2,3\({}^{\prime}\),4,4\({}^{\prime}\),5,5\({}^{\prime}\)-hexaCB(\#167) & 19 & 360 & 64 & 14 & 36 & 13 \\ \cline{2-8}  & 2,3,3\({}^{\prime}\),4,4\({}^{\prime}\),5-hexaCB(\#156) & 36 & 870 & 110 & 24 & 61 & 25 \\ \cline{2-8}  & 2,3,3\({}^{\prime}\),4,4\({}^{\prime}\),5-hexaCB(\#157) & 12 & 200 & 25 & 5.8 & 15 & 6.1 \\ \cline{2-8}  & 2,3,3\({}^{\prime}\),4,4\({}^{\prime}\),5,5\({}^{\prime}\)-heptaCB(\#189) & 4.1 & 33 & 15 & 2.0 & 3.8 & 2.6 \\ \hline \multicolumn{2}{c}{DL-PCBs TEQ (pg-TEQ/g-dw)} & 1.92 & 11.72 & 5.01 & 1.42 & 4.21 & 2.22 \\ \hline \multicolumn{2}{c}{TOTAL TEQ (pg-TEQ/g-dw)} & 1.92 & 12.44 & 5.27 & 1.48 & 4.21 & 2.33 \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Detected concentrations of individual PCDD/Fs and DL-PCBs (pg/g-dw) and total TEQ value (pg-TEQ/g-dw) in wharf roach collected from 11 sampling sites (sample from SAS, Miyagi, was not available). The PCDD/F congener composition differed among the 11 sampling sites. The highest-concentration congener was OCDD in all sampling sites, and this trend was more noticeable in the work by ISH, NOR, and NOT (100%, 100%, and 98%, respectively, Figure 3, Table S1: supplementary materials). In other sites, the OCDD burden was similar (44.6%-61.3%). However, other congeners were different.