HiWATE project partners: Centre for Research in Environmental •Epidemiology, SpainImperial College London, United Kingdom•University of the Aegean, Greece•National Public Health Institute, Finland•Vytautas Magnus University, Lithuania•University of Crete, Greece•Université de Rennes, France•Municipal Institute of Medical Research •Foundation, Spain

Centre for Genomic Regulation, Spain•University of Modena and Reggio, Italy•Istituto di Ricerche Farmacologiche “Mario •Negri”, ItalySwedish Institute for Infectious Disease •Control, SwedenHylobates Consulting Srl, Italy•Imperial Consultants Ltd, United Kingdom•Scarab, Sweden•Catalan Institute of Cancer, Spain•

Dr Mark Nieuwenhuijsen1, Dr Radu Rautiu2, Katie Weeks2, Marta Kowalewska2 and the HIWATE project team. 1 Centre for Research in Environmental Epidemiology (CREAL) Barcelona, 2 Imperial College London Consultants Ltd.

TreaTed drinking waTer in europe may cause healTh risks

The standard of drinking water in Europe is high. Over 60% of people in Northern European Countries such as the Netherlands and the United Kingdom drink water straight from the tap.

Chemical treatment of water sources such as ground water, surface water and sea water is vital to produce safe drinking water.

However the process of treating water to make it drinkable may itself cause health risks to those drinking it.

waTer disinfecTion can produce carcinogens as a by-producT

In the 1970s trihalomethanes (THMs) were discovered in drinking water1. THMs are environmental pollutants, many of which are considered carcinogenic, that are a by-product of chlorine disinfection. These by-products are formed when the organic matter in water reacts with chlorine.

Chlorine disinfection is the most common method of water treatment in Europe. Alternative methods include ozonation which can create the harmful disinfection by-products bromate and chlorite.

Long-term exposure to these disinfectant by-products (DBPs) have been associated with health risks including cancer and birth defects2.

previous sTudies on disinfecTanT by-producTs have focused on The uniTed sTaTes

Disinfection by-products (DBPs) have been largely ignored by researchers in Europe. Little is known about any DBPs other than trihalomethanes (THMs).

In contrast the US has carried out extensive surveys to assess the levels of DBPs from various water treatment methods3.

Recent studies have shown that drinking water containing DBPs is not the only method of absorption – showering, swimming and bathing are also contributors4,5. Many studies of DBP exposure have not taken these methods of absorption into account.

The hiwaTe projecT is The mosT in-depTh sTudy of by-producTs in europe

HiWATE began in November 2006 and is scheduled to end in 2010. The focus of the project is to address the shortage of European research into the effects of disinfection by-products. It will also address the shortage of research into absorption methods other than drinking. Over 16 countries are taking part in the study, which is divided into four research areas:

exposure assessmentCollection of water samples over two years from regions within the United •Kingdom, France, Spain, Greece, Italy and Lithuania. Analysis of samples for disinfectant by-products including trihalomethanes •and haloketones Analysis of these by-products used to develop predictive models taking into •account exposure through swimming, bathing and showering

reproductive epidemiological studiesEvaluate strength and length of exposure to disinfectant by-products for any •association with reproductive health risks, including semen quality, premature births, still births and congenital anomalies

cancer epidemiological studiesEvaluate the relationship between DBP exposure and the risk of colorectal •cancer as current evidence associating DBP exposure with cancer is inconclusive and inconsistent

Risk/benefit analysis and policy implicationsComparison of alternative treatments to chlorine disinfection•Study risks of leaving water untreated compared to those of drinking treated •water Use funding to develop guidelines and recommendations for the European •Union

references

Rook JJ. Formation of haloforms during chlorination of natural waters. J Soc for Water Treatment and Examination, 19741. IPCS. Disinfectants and disinfectant by-products. Environmental Health Criteria 216, World Health Organisation Geneva 20002. Weinberg et al. The occurrence of disinfection by-products of health concern in drinking water: the results of a nationwide DBP 3. occurrence study. EPA report 600/R-02/068 2002Nieuwenhuijsen et al. Uptake of chlorination disinfection by-products; a review and discussion of its implications for 4. epidemiological studies. J Expos Anal Environ Epidemiol 2000Villaneuva et al. Bladder Cancer and exposure to water disinfection by-products through ingestion, bathing, 5.

HiWATE is sponsored by the European Commission andisaSpecificTargetedResearchProject(STREP)funded under the EU Sixth Framework Programme for

Research and Technological Development (FP6)

www.hiwate.eu

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