What are Iron Bacteria?

Iron bacteria  are chemotrophic bacteria that oxidize iron. They use it as a food source to facilitate growth. Iron bacteria will also produce distinctive colony groups in the presence of enough iron. They can form braids and branch-like colonies with iron embedded in the cell walls which gives them a shiny appearance when viewed microscopically.


While harmless to humans, iron bacteria can foul water systems and defeat disinfection efforts by growing on and in pipes, well tips, and other system components.  They can produce unpleasant tastes, odors, and contribute to color in water. These bacteria can be concentrated from drinking water using either centrifugation or filtration and examined microscopically.  The species of iron bacteria is identified and the bacterial abundance is reported (Standard Method 9240B).