[The effect of water pipelines on the quality of drinking water].

The purpose of the study was to assess the effects of various pipelines on drinking water quality. For the study carried out in Warsaw buildings were chosen in which the installations were made of polypropylene, polyvinyl chloride, copper and steel. Water samples were taken from the sites of water leading to the buildings and from the highest floors, if possible.

[Actual standards for drinking water quality].

Actual recommendations concerning drinking water quality are presented in WHO "Guidelines for drinking water quality" published in 1992. Regulations which are obligatory in the European Union countries are published in Directive 80/778/EEC. In 1995 a proposal of a new Directive was elaborated.

[Occurrence of aquatic organisms in water pipes and the resulting problems with drinking water disinfection].

The present text is the first part of a paper aimed at specification of the requirements ensuring effective disinfection of drinking water. The discussed health hazards result not only from the presence of pathogenic microorganisms in water, but also from the occurrence of micro- and macroscopic plant and animal organisms. It was shown that while the traditional method for water treatment and disinfection reduces the number of these organisms, it fails to eliminate them completely, particularly in the case of tap water intake from shore intakes of surface waters.