Oxidation of sulfur dioxide (SO2) may form various atmospheric air pollutants, which is caused by natural processes or human activity. Chemical composition of the atmosphere and biosphere can change depending on the efficiency of the oxidation processes. Atmospheric gases like H2SO4 released by the oxidation of SO2 is naturally removed from the atmosphere through oxidizing chemical reactions. Human activity can increase the amount of gases in the atmosphere, therefore it can affect the oxidation capacity. As a result of OH reaction, these gases are destroyed and removed from the atmosphere. OH reaction converts SO2 to sulfuric acid H2SO4. Rain carries the sulfuric acid to biosphere or hydrosphere.