Is ozone only harmful for humans?

No, ozone pollution also has consequences for the environment and the economy. After short exposure to high ozone concentrations, some plants show visible leaf damage. In addition, ozone also has a cumulative harmful effect on crops, manifested as lessened growth and stress resistance. The affliction by ozone gets worse as the stomata open further by for example increased air or soil humidity. Exposure to high ozone concentrations will decrease the yield of grain, amongst others. During 'normal' summers, the potential yield loss of grain crops in Belgium is estimated at about 5%. In warm summers, this can increase up to almost 20%.

Because of its high reactivity, ozone also influences the surface of materials such as some plastics and paints, which might result in discolouration.