Hygienic Significance of Chlorine and Chlorine Compounds in Drinking Water.

As is known, various chlorinated organic compounds are formed as undesirable by-products of drinking water chlorination. It is regarded as more expedient to prevent the formation of these compounds rather than to remove them after they have formed. The use of chlorine dioxide for this purpose has been considered, but it has the negative effect of forming chlorites and chlorates. It therefore seems more advantagaeous to eliminate precursors, such as humic acid, prior to chlorination by means of ozonation or activated carbon filtration. Finally, for this removal or decomposition of halogenated organic compounds which arise as chlorination by-products or for the elimination of industrial products, such as chlorinated solvents, from drinking water radiation treatment with ionizing or ultraviolet rays is of great interest and has been found to be very promising in experiments carried out hitherto.