Introduction

High ambient concentrations of ozone in the troposphere during sunny episodes are one of the main problems of air pollution in Europe. Ozone causes damage to human health, plants, animals and materials. Damage to human health includes irritation of respiratory tracts and eyes and reduction of lung function and physical power; in addition, ozone may cause or intensify chronic respiratory diseases. Furthermore, ozone decreases the photosynthesis rate in plants; this reduces for example crop yield and puts additional stress on forests. Materials containing carbons like paints, rubber and certain synthetics are affected.