Table 7 Top 5 substances by source (percent) - Quebec
| Â | Percent contribution to total substance emitted | ||||||
|---|---|---|---|---|---|---|---|
| Substance | Airports | NPRI | Rail | Res gas | Res oil | Res wood | Roads |
| Arsenic | 2 | 97 | <1 | <1 | 0 | 1 | 0 |
| Benzo[a]pyrene | 0 | 65 | 0 | <1 | <1 | 35 | 0 |
| Benzene | <1 | <1 | <1 | <1 | 0 | 13 | 87 |
| TCDD | 0 | 0 | 0 | 0 | 6 | 94 | 0 |
| Lead | <1 | 88 | <1 | 0 | <1 | 1 | 10 |