[Extent and evaluation of air pollution in Switzerland]

The measurements of atmospheric pollution carried out in Switzerland during the last years revealed that high concentrations are not only found in city centers but in suburbs as well. The emission limits which should be respected in order to protect health and environment are very often exceeded. The pollution through nitrogen dioxide is specially crucial as well as that of sulfur dioxide during the winter months. Ozone concentrations are remarkably high in summer--ozone being formed by photochemical reactions of nitrogen oxides and hydrocarbons--and can be transported far away, even in rural areas. It is urgent to take the necessary steps now to reduce the atmospheric pollution in order to protect the population against possible health damages.