Abstract
Recently, social concerns regarding tap water quality have increased mainly because of the possible reduction in safety due to the contamination of tap water with various chemicals and the increase of strange odors and tastes in tap water as a result of the eutrophication in resource water. Consequently, the Ministry of Health and Welfare conducted a detailed two-year investigation of the Water Quality Standards of the Water Works Law by summoning an expert committee, and as a result, totally revised the Standard in December 1992. This was the first overall revision since 1958 when the Water Quality Standard was established, and an additional 21 items, including mainly hazardous chemicals including pesticides and chlorinated by-producets, were newly added. Simultaneously, 26 monitoring items on hazardous contaminants guidelines which should be applied, when necessary. Analytical methods for drinking water were summarized and preparation, analytical systems and detecting limits.
