Microbiologically Influenced Corrosion (MIC):

MIC is an acronym for microbiologically influenced corrosion, a mode of corrosion incorporating microbes that react and cause the corrosion or influence other corrosion processes of metallic materials.

Most materials, including metals, polymers, glass and ceramics can be degraded in this manner.

A number of microbiological organisms, notably bacteria, fungi and algae have been associated with corrosion damage in water systems. These microorganisms can influence corrosion by effects such as differential aeration cells, the production of corrosive species such as mineral and organic acids, ammonia, and reduction of sulfate to sulfide.

The various types of microbes tend to act synergistically in the corrosion of materials with their interactions typically being of a complex nature.

Even though the harmful corrosive influence of microbes has been known for more than 60 years, many practicising engineers are still surprised to learn that the activity of microorganisms can lead to severe degradation of various construction materials.