A total of 24 bacterial isolates able to grow on metal-working fluids were obtained from soil or metal-working fluids (both in-use and heavily contaminated fluids). Pure cultures of the isolates were tested for their ability to degrade a selection of components, including berate esters, phosphate ester, biocide and triethanolamine, typically found in synthetic metal-working fluids. All components, when present at a level equivalent to half that found in an in-use metal-working fluid, supported growth when utilised as the sole source of carbon and/or nitrogen. Each component was degraded by at least 50% by an individual isolate within 120 hours in batch liquid culture.