Discriminating bacterial from electrochemical corrosion using Fe isotopes

Metal corrosion is microbially induced (MIC) and/or electrochemical (ECC) in origin. Here we provide a novel approach to distinguish MIC from ECC, using iron isotope fingerprinting technique. In laboratory experiments, MIC products of Fe in the presence of a pure strain of Thiomonas sp. WJ68 exhibit a major shift in Fe isotope ratios (δ56/54Fe and δ57/54Fe, by 1.26 and 1.95‰, respectively) compared to ECC products formed under identical but sterile conditions. The methodology has applications in a broad range of industrial environments, particularly in the petrochemicals sector.