Models for corrosion influenced by iron-oxidizing bacteria (IOB) in fresh water are specific for
material/environment combinations, i.e., 300 series stainless steel exposed to oxygenated chloridecontaining
potable water and carbon steel exposed in oxygenated fresh water ([Cl-] = 20 ppb) containing
dissolved copper. Reports of IOB influenced corrosion in marine environments have been limited to
rusticle formation on shipwrecks. IOB involved in corrosion in fresh water include Gallionella,
Leptothrix, and Siderocapsa. Historically these organisms have also been thought to be active in marine
environments. New isolation and molecular identification techniques are demonstrating the presence of
novel IOB in both freshwater and marine environments, and expanding our understanding of their
potential role in microbiologically influenced corrosion.
Key words: iron-oxidizing bacteria, microbiologically influenced corrosion, freshwater, marine, steel,
copper