Table 2.
Toxicological data and carcinogenic risk
| Chemical |
Unit risk (µg/m3)−1 |
Unit risk source a | Unit risk basis | Chemical-specific riskb | |||
|---|---|---|---|---|---|---|---|
|
Seoul (N = 85) |
Incheon (N = 112) |
Busan (N = 128, 158)c |
Daegu (N = 83) |
||||
| As | 0.0043 | IRIS | Air | 4.21E-06 (62.9) | 6.56E-06 (67.1) | 3.22E-06 (41.9) | 4.82E-06 (39.8) |
| Co | 0.009 | PPRTV | Air | 1.62E-06 (24.2) | 2.03E-06 (20.8) | 2.12E-06 (27.6) | 5.69E-06 (47.0) |
| Ni | 0.00024 | IRIS | Air | 2.62E-07 (3.9) | 5.14E-07 (5.3) | 1.14E-06 (14.8) | 7.52E-07 (6.2) |
| Cd | 0.0018 | IRIS | Air | 5.11E-07 (7.6) | 5.27E-07 (5.4) | 1.07E-06 (13.9) | 6.82E-07 (5.6) |
| Pb | 0.000012 | OEHHA | Air | 9.71E-08 (1.4) | 1.39E-07 (1.4) | 1.35E-07 (1.8) | 1.60E-07 (1.3) |
| Incremental lifetime cancer risk | By the sum of chemical-specific risks using measured data | 6.70E-06 (100) | 9.77E-06 (100) | 7.68E-06 (100) | 1.21E-05 (100) | ||
| By the sum of source specific risks using PMF results | 6.69E-06 | 1.03E-05 | 7.59E-06 | 1.22E-05 | |||
a(US EPA 2021)
bThe numbers in parentheses are the proportion (%) of chemical-specific cancer risk in cumulative ILCR in the city
cN = 128 for Pb; N = 158 for other metals