Assessment of the marker value of various components of thecoli‐aerogenesgroup of Enterobacteriaceae and of a selection ofEnterococcusspp. for the official monitoring of drinking water supplies

摘要

The traditional indicatorsEscherichia coli(in practice currently, though ecologically inaccurately, represented by ‘thermotolerant coliforms’ at 44°C) andEnterococcusspp. proved to be suitable for the diagnosis of heavy and frequent faecal pollution observed in potentially dangerous waters, especially those originating from karstic aquifers. On the other hand, natural and treated waters, slightly and inconsistently contaminated, occasionally showed a variable Gram‐negative flora, difficult to classify by routine tests. In that case, complete identification of isolates may be necessary to ensure a valid decision on the potability of the supply. At any rate some of the Enterobacteriaceae contained in the ‘faecal coliform’ group and many other ‘coliforms’, distinct fromE. coli, lack sanitary significance although their presence at certain levels may indicate inadequate disinfection, hiatuses in the integrity of the distribution