Cultivation-Based Identification of Microorganisms in Metalworking Fluids and Their Role in Hydrocarbon Degradation

Water-miscible metalworking fluids are widely used in industrial processes. Despite the fact that they typically contain biocides, they are almost always colonized by microorganisms, which degrade different components of the liquid, may clog machines due to biofilm formation, and might pose a health risk to workers. In this study, samples from four metalworking machines operated with the same metalworking concentrate were analyzed with respect to microbial growth. Twenty-seven bacterial species and one fungus were identified. From these, twenty species were not observed before as colonizers of metalworking fluids. Growth of microorganisms, putative contamination sources, metabolic pathways involved in biodegradation, and resulting health risks are analyzed and discussed in this study.