Biological health risk assessment
Quality of water intended for human consumption ? Control objectives and issues

It is often difficult, and time-consuming, to count pathogenic micro-organisms in water, mainly because of their small numbers. For some micro-organisms, analytical methods are insufficiently developed (impossible culture on medium, etc.).

It therefore seems preferable to count pathogenic indicator micro-organisms, which are generally easier to detect and whose presence corresponds to the possibility of finding a given pathogen or group of pathogens.

• Special features of pollution monitors

  Pollution indicators have been defined on a number of occasions, and were reiterated in 1972 at the Stockholm conference organized by the United Nations. There...