The survival of Legionella pneumophila in dilute metalworking fluids

Abstract

L. pneumophila, the causative organism of both Legionnaires' disease and Pontiac fever, has been occasionally isolated from dilute metalworking fluids. These contaminated fluids have been associated with sporadic incidences of these diseases in workshop environments. This paper examines the survival of L. pneumophila in several metalworking fluids under laboratory conditions. In the fluids tested L. pneumophila did not multiply but was reduced in numbers. The rate of decline in viability varied from fluid to fluid and between fresh and spoiled fluids. The use of biocides to control L. pneumophila in metalworking fluids is examined. Biocides are postulated as a method of maintaining a hostile environment for potentially pathogenic organisms as well as controlling any microbially induced problems such as foul odours, slimes and biocorrosion.