Oxidants in Daily Life and Common Health Conditions

Mutagenesis
Possibly the most important source of mutagenic alterations in DNA is oxidative damage. Reactive oxygen species such as hydroxyl radicals and superoxide radicals arise during irradiation or as a byproduct of aerobic metabolism. Of these species, the hydroxyl radicals are responsible for most oxidative DNA damage. Cells have an elaborate defense system to destroy reactive oxygen species. A fraction of these oxidants escape cellular defense, however, and cause damages to DNA. Everyday, the DNA of each human cell is subjected to thousands of damaging oxidative reactions. Much evidence suggests an intimate link between the accumulation of mutations and the process of carcinogenesis.