Table
| 2012 | Change in per cent | ||
|---|---|---|---|
| Since 1990 | 2011 - 2012 | ||
| 1Does not include international sea and air traffic. | |||
| Nitrogen oxides (NOX) | 166 | -13.3 | -4.6 |
| Sulphur dioxide (SO2) | 17 | -68.1 | -9.5 |
| Ammonia (NH3) | 27 | 10.7 | 1.1 |
| Non-methane volatile organic compounds (NMVOC) | 137 | -53.2 | 1.0 |
| Carbon monoxide (CO) | 301 | -59.8 | -2.8 |