Abstract
As I already mentioned, ozone (from the Greek means to give off a smell) is a natural but unstable molecule. The pure gas has a soft sky-blue colour with a pungent, acrid smell. The molecule is composed of three oxygen atoms (O(3)) and, the molecular weight, in comparison to the oxygen diatomic molecule (32.00) is of 48.00. Ozone has a cyclical structure with a distance among oxygen atoms of 1.26 Å and exists in several mesomeric states in dynamic equilibrium. For the physician it is useful to know that the solubility (ml) in 100 ml water (at 0°C) of either ozone or oxygen is either 49.0 ml or 4.89 (ten fold lower), respectively. Consequently the great solubility of ozone in water allows its immediate reaction with any soluble compounds and biomolecules present in biological fluids. Either traces of oxygen polymers (O(4)) or ozone polymers (O(6) and O(9)) can be generated but the idea that superactive ozone polymers/clusters may have a therapeutic role remains speculative (Cacace et al., 2001; Murai et al., 2003).