| Pollutant |
Main Sources |
UK Figures |
| Nitrogen oxides (Nox) |
Combustion of motor spirit and other fuel, combustion for domestic heating, power stations, industrial boilers, chemical processes etc. |
Road transport 44% Power stations 21% Other industry 9% |
| Sulphur dioxide |
Fuel combustion for power stations, domestic heating, industrial boilers, diesel vehicles, waste incinerators. |
Power stations 65% Other industry 10% Refineries 8% |
| Carbon monoxide |
Combustion of motor spirit and other combustion processes. |
Road transport 69% Off-road sources 9% Domestic 5% |
| Ozone |
Secondary pollutant resulting from chemical reactions with nitrogen oxides and VOCs. |
See NOx & VOCs. |
| Particulates |
Fuel combustion for power stations, transport, heating, other industrial processes. |
Construction, mining, quarrying 13% Road transport 20% Power stations 10% Domestic 20% |
| Volatile Organic Compounds (VOCs) |
Transport, oil combustion, chemical processes, solvent use, waste incinerators. |
Road transport 27% Solvent use 27% Extraction & distribution of fossil fuels 15% Production processes 12% |
| Benzene |
Combustion of motor spirit, evaporation from petrol pumps and fuel tanks. |
Road transport 71% |
| Lead |
Combustion of leaded petrol, coal combustion, metal production. |
|