Started in 1948, Kiwa Water Research has developed into an internationally respected research center in the field of drinking water and related environmental issues. The 120 scientific specialists conduct the joint research program of the water supply companies in the Netherlands, and also provide research services for other national and international clients.While the major focus is on drinking water supply, Kiwa is also involved in projects addressing the integration of the water chain, including water for industrial and other use. Core tasks of the division include innovative research and transfer of knowledge and know-how.Other divisions of Kiwa provide a range of certification, inspection and management consultancy services for water businesses and other sectors of industry.More information can be found on www. The publisher makes no representation, express or implied, with regard to the accuracy of the information contained in this book and cannot accept any legal responsibility or liability for errors or omissions that may be made. DisclaimerThe information provided and the opinions given in this publication are not necessarily those of IWA, KIWA or the editors, and should not be acted upon without independent consideration and professional advice. IWA and the editor will not accept responsibility for any loss or damage suffered by any person acting or refraining from acting upon any material contained in this publication. British Library Cataloging in Publication Data SUMMARYWater quality management requires knowledge about all aspects that can have an impact on water quality. From toxicological point of view the presence of organic micro-pollutants in raw water and consequently drinking water, is one of these aspects. Taking into account that these compounds are usually found in relatively low concentrations, the main research attention of drinking water industry is focused on the (suspected) presence of mutagenic and carcinogenic compounds. Up to now only lipophilic (= less soluble in water) compounds were analysed within research on the occurrence of mutagenic and carcinogenic compounds in water. These compounds were isolated from water using XAD-resins. It was proved that they contain approximately half of the total organic material present in water. A clear mutagenic effect was demonstrated for these compounds using the Ames test.Up to now, the hydrophilic (= very good soluble in water) part of the organic material could be hardly included in the research. This material is namely difficult to isolate and analyse due to its high solubility. The high solubility means also that the hydrophilic compounds are mobile in conventional treatment systems and in water conveying (ground) pockets. They can easily penetrate into drinking water. Because of this, it is very important to know, what is the toxicological meaning of this hydrophilic material.Eight different water types, including strongly polluted industrial water, were examined to determine the role of hydrophilic material. A method was developed to ...