Pathogens in Metal Working Fluids

Manufacturers of metal working fluids (MWF) are continually attempting to design fluids that are unpalatable to microbial colonizers. Despite this incidence of microbial invaders able to induce disease and allergic effects continue and may even be increasing. In recent years the introduction of new water based MWF formulations, and changes in management practices, have resulted in particular problems with regards to microbial contamination and growing evidence suggests that exposure to MWF aerosols, can lead to increased risk of non-infectious health hazards, such as hypersensitivity pneumonitis (HP). Several incidences, since 1993, indicate a correlation between incidence of HP with the presence of Mycobacterium and the identification of a new taxon, M. immunogenum. Interestingly the reported incidence of M. immunogenum has increased in recent years, in particularly in metal workshops in the USA. However, it is unclear whether this is due to the increased spatial distribution or vigor of the species, or simply the greater level of surveillance and awareness. The increasing application of state of art molecular detection methods, that improve Mycobacterium detection sensitive and speed, are discussed.