Rapid assessment techniques for chemicals in raw water sources

Chemical water quality monitoring is essential in areas where the harmful effects of naturally occurring or artificially introduced chemicals on health are significant. It is very difficult for developing countries to monitor a large number of chemicals due to human and financial constraints and hence simple guidelines are required in selecting and prioritising chemicals in the monitoring programmes. The aim of this paper is to review various screening procedures and rapid assessment techniques to identify the presence of chemical contaminants in raw water sources. Surrogate parameter techniques and the land use and hydrology of an area are useful in screening for selection of the parameters to be included in a water quality monitoring programme. Bioassays, immunoassays, biological monitoring and ‘sum parameters’ such as total organic carbon (TOC) and adsorbable organic halogens (AOX) are very promising rapid assessment techniques. However, technical and economic evaluation is required for their application in developing countries. The development of guideline values for TOC and AOX is recommended.