There are now over 700 million motor vehicles in the
world – and the number is rising by more than 40 million
each year. The average distance driven by car users is
growing too – from 8km a day per person in western Europe
in 1965 to 25 km a day in 1995. This dependence on motor
vehicles has given rise to major problems, including
environmental pollution, depletion of oil resources,
traffic congestion and safety.
While emissions from new cars are far less harmful than
they used to be, city streets and motorways are becoming
more crowded than ever, often with older trucks, buses
and taxis which emit excessive levels of smoke and fumes.
This concentration of vehicles makes air quality in urban
areas unpleasant and sometimes dangerous to breathe.
Even Moscow has joined the list of capitals afflicted by
congestion and traffic fumes. In Mexico City, vehicle
pollution is a major health hazard.