THE MICROBIOLOGY OF LUBRICANTS AND OILS FOR WATER-SUPPLY APPLICATIONS

Recent work in the US has shown that contact between lubricants and oi ls and drinking water can promote the growth of heterotrophic micro-or ganisms. It is unlikely that these species are pathogenic, and therefo re harmful to man. However, the hygienic status of water distribution systems could be affected, leading to higher heterotrophic plate count s during routine sampling. Experimental work has been undertaken to st udy the microbiological impact of a range of lubricants and oils on dr inking water. The methods have been based on an existing procedure for the assessment of the growth potential of drinking water, i.e. the 'a ssimilable organic carbon' test. The results of this work could serve as the basis of a future standard method for the sapid and inexpensive screening of oils and lubricants for their microbiological suitabilit y in potable-water applications.