[The public health relevance of various microbiologic marker pathogens for assessing bathing water]

Regarding the quality of natural recreational water for bathing purposes, the limit values of E. coli and coliforms, faecal coliforms and totalcoliforms, respectively, laid down by the Council of the European Community, differ considerably from those prescribed by some Land Governments of the Federal Republic of Germany and by the DIN Standard Regulation No. 19643 entitled 'Processing and Disinfection of Water in Swimming Pools and Basins in Public Baths'. It must be concluded by virtue of hygienically plausible considerations, as well as for juridical reasons, that only the limit values of the EC-Code of Practice are authoritative, whereas standards of the DIN 19643, especially in respect of E. coli and coliforms, differing from the limit values of the EC-Code of Practice are not legally binding. Moreover, coliforms are not relevant for controlling swimming pools and basins in public baths. Staphylococcus aureus should therefore be investigated instead whereas other parameters such as E. coli, Pseudomonas aeruginosa, and total colony counts are good markers. However, the standards of these organisms as established by the DIN 19643 are more in line with technical practibility and biased aesthetics instead of the hygienically important prinicple of commensurability.