International Biodeterioration & Biodegradation 53 (2004) 177–183
www.elsevier.com/locate/ibiod
Corrosion of technical materials in the presence of bio%lms—current
understanding and state-of-the art methods of study
Iwona B. Beech∗
School of Pharmacy and Biomedical Sciences,University of Portsmouth, St. Michael’s Building White Swan Road, Portsmouth P01 2DT, UK
Abstract
It is documented that bio%lms are capable of in*uencing electrochemical processes at the metal surface, often leading to deterioration
of metals referred to as biocorrosion or microbiologically in*uenced corrosion. Bio%lms typically consist of microbial cells and their
metabolic products including extracellular polymers, and inorganic precipitates. Interaction of bio%lms and exopolymers with metal ions
has long been proposed as one of the mechanisms of metal biodeterioration.
This paper presents an overview of the application of modern microscopy and surface analysis techniques in studying the involvement
of bio%lms and extracellular polymeric material in the biocorrosion process of metals and their alloys.
? 2003 Elsevier Ltd. All rights reserved.
1. Bio
lms and biodeterioration
The term bio%lm refers to the development of microbial
communities on submerged surfaces in aqueous environ-
ments (Characklis and Marshall, 1990). The growth of
bio%lm is considered to be a result of complex processes
involving transport of organic and inorganic molecules and
microbial cells to the surface, adsorption of molecules to
the surface (formation of the conditioning layer) and initial
attachment of microbial cells followed by their irreversible
adhesion facilitated by production of extracellular poly-
meric substances (EPS), often referred to as the glycocalyx
or slime (Costerton et al., 1978). The biofouling and biode-
terioration of man-made materials, including metal and their
alloys, due to the bio%lm formation has great environmental
and economical implications. Many industrial sectors such
as gas, oil, nuclear power, shipping, aircraft, chemical and
civil