In nature, oxygen more frequently occurs in the O2 state which is far more stable. Ozone is more commonly known as the layer of the atmosphere which protects plants and animals from the damaging effects of ultraviolet radiation from the sun. It is also known as a pollutant that builds up in the lower part of the atmosphere on warm days as a result of chemical reactions, driven by the heat of the sun, when nitrogen dioxide and hydrocarbons from vehicle exhaust react with oxygen. In this form, ozone can cause irritation and sometimes damage to the mucosal membrane of the respiratory tract and the eyes.
Ozone can also be useful in the treatment of water.
Known as a strong oxidant, ozone can be used in the water purification process as a method of killing bacteria and other microorganisms in the water supply. This practice has become quite controversial. Most researchers believe ozone has no medical use. There are several different forms of ozone therapy which are sometimes referred to as superoxidation or hyperoxidation. Ozone therapy can be administered in three different ways.