The Microbiology of Lubricants and Oils for Water Supply Applications

Recent work in the US has shown that contact between lubricants and oils and drinking water can promote the growth of heterotrophic micro-organisms. It is unlikely that these species are pathogenic, and therefore harmful to man. However, the hygienic status of water distribution systems could be affected, leading to higher heterotrophic plate counts during routine sampling. Experimental work has been undertaken to study the microbiological impact of a range of lubricants and oils on drinking water. The methods have been based on an existing procedure for the assessment of the growth potential of drinking water, i.e. the 'assimilable organic carbon'test. The results of this work could serve as the basis of a future standard method for the rapid and inexpensive screening of oils and lubricants for their microbiological suitability in potable-water applications.