Congener WHO-TEF DL [ng kg-1DM] Concentration WHO-TEQ Concentration [ng kg-1DM] [ng WHO-TEQ kg-1DM] A B1 B2 B3 A B1 B2 B3 PCB 77 0.0001 1 492.0 71.0 172.0 191.0 0.0492 0.0071 0.0172 0.0191 PCB 81 0.0003 1 19.6 <DL 1.4 1.9 0.0059 0.0002 0.0004 0.0006 PCB 105 0.00003 1 1890.0 233.0 650.0 700.0 0.0567 0.0070 0.0195 0.0210 PCB 114 0.00003 1 162.0 <DL 48.0 59.0 0.0049 0 0.0014 0.0018 PCB 118 0.00003 1 5210.0 1290.0 1800.0 1800.0 0.1563 0.0387 0.0540 0.0540 PCB 123 0.00003 1 403.0 35.0 136.0 126.0 0.0121 0.0011 0.0041 0.0038 PCB 126 0.1 1 5.2 <DL 1.4 7.1 0.5200 0.0500 0.1400 0.7100 PCB 156 0.00003 1 600.0 151.0 343.0 343.0 0.0180 0.0045 0.0103 0.0103 PCB 157 0.00003 1 99.0 32.0 67.0 52.0 0.0030 0.0010 0.0020 0.0016 PCB 167 0.00003 1 141.0 55.0 97.0 114.0 0.0042 0.0017 0.0029 0.0034 PCB 169 0.03 1 7.0 2.1 2.8 6.4 0.2100 0.0630 0.0840 0.1920 PCB 189 0.00003 1 53.0 14.0 20.0 18.8 0.0016 0.0004 0.0006 0.0006 Total - - 9081.8 1884.6 3338.6 3419.2 1.0418 0.1746 0.3365 1.0181

Table 2: PCB concentrations and respective WHO-TEQ concentrations in sludge samples for the WWTP taken as reference for the population exposed to POP contamination (A) and for the background WWTPs (B1, B2 and B3); concentrations below the DL are assumed equal to half the DL itself for the calculation of the total concentrations.