Vehicles are a major source of air pollution. Their emissions release alarmingly high levels of nitrogen oxides, hydrocarbons and lead into the atmosphere, damaging human health, buildings, plants, fresh water and forests, as well as contributing to climatic change and ozone depletion.;Government policies regarding the vehicle industry stem from a variety of concerns, principally those of employment, the balance of trade and technological progress. Taxation of vehicles and fuel is an important source of government revenue. In addition the car remains a symbol of mobility and independence.;In December 1990, the Council of Ministers of the European Community agreed the mandatory introduction, for all new cars from 1993, of emission limits for exhaust gases requiring world best practice emission abatement technology: the fully-regulated autocatalyst. Agreement was finally reached after a decade of considerable controversy, with German and British interests - two extremes in the argument - set on a collision course.;During the 1980s, Britain, committed to privatization, reductions in public spending, and deregulation, abated vehicle emissions only reluctantly, largely as a defensive reaction to pressure from abroad. On the other hand, German action to abate acid emissions was internally motivated and earned it a much higher environmental profile.;Anglo-German differences were revealed in EC negotiations, which also highlighted the technical complexities of policymaking for the pollution control of major industries and the importance of commercial considerations.