Emissions

Transport is a major contributor to the emissions of greenhouse gases.
Road transport is currently the greatest contributor, accounting for 80 percent of the CO₂ emissions coming from transport and 60 percent of all NO_X emissions.

NO_X result from the combustion of fuels under high pressure and temperatures. NO_X contribute indirectly to the greenhouse effect  and directly to acid rain  and the tropospheric ozone formation.


Carbon monoxide is created through incomplete fuel combustion from petrol engines. Carbon monoxide can be hazardous to health, particularly interfering with the absorption of oxygen in blood.

VOC emissions arise from incomplete fuel combustion and evaporation of fuel from petrol engines and service stations. VOCs contribute to tropospheric ozone depletion .

Particulate matter comes primarily from diesel engines, with emissions 50 times greater than for petrol engines. Particulate matter can remain in the air for considerable periods of time and contribute to smog formation. Particulates are damaging to human health; fine particles can settle and remain in the lungs, leading to respiratory diseases and cancer.

Routine and accidental releases of oil or chemical substances into the environment by lorries and tankers contribute to the pollution of soil, rivers and seas.