[Nematodes in drinking water: analysis of an Italian case]. / Nematodi in acque potabili: analisi di un caso italiano.

The paper describes an infestation by nematodes in a municipal drinking water plant in Eastern Italy. The procedures for detecting the public health significance of these presences and the measures for avoiding risks for population are reported. Furthermore the preliminary results of the analyses of water from a pilot plant carrying a Diatomeaceus Hearth Filtration are reported.

[Microbiological profile in water-supply conduits from a clogged well]. / Rilevamenti microbiologici in condotte di rifornimento idrico di un pozzo occluso.

This article presents the results of an investigation involving bacterioflora in a water well clogged for the presence of biomass. The water well, placed in a zone near Rome, showed some problems about the water quality and about the extraction of water. The examination of the interior of the pipes showed the presence of biomass. The biomass was examined microscopically and bacteriological analyses were carried out on it. Heterotrophic bacteria were enumerated with three different media by direct count, Pseudomonas sp., yeasts and fungi also by spread plate method. The anaerobic Sulphate Reducing Bacteria were investigated by "Most Probable Number" technique. The results of the analyses showed the presence of protozoa and algae. Moreover high quantity of bacterial flora as heterotrophic bacteria and Pseudomonas sp. were revealed. Sulphate Reducing Bacteria were enumerated in low quantities. Sphaerotilus natans, Actinomyces and Rhodotorula were identified. The clogging problems arose from the presence of filamentous microorganisms as Sphaeroilus natans and Actinomyces sp. When microorganisms of this kind are present in aquifers they can multiply massively if the conditions are favorable.