Human activities result in the release of both microbial and chemical contaminants into the aquatic environment, which may be a threat to human and environmental health. Newly recognised potential hazards in the aquatic environment are often referred to as emerging contaminants. During the last decades, new risks for drinking water resource quality frequently emerged due to the increased sensitivity of our analytical techniques and climatological, technical, societal and demographic changes.
A common approach to detect emerging contaminants in drinking water resources is identification through screening efforts. This approach is rather ad-hoc and reactive as we start to act when the contaminants have already reached the drinking water resources. In addition, once identified, mitigation actions should focus on those contaminants posing the highest threat to public health via drinking water. Prioritisation of action on emerging drinking water contaminants is challenging as they are different by nature, evidence about their hazard and exposure potential is often scarce, and experts might disagree on its evaluation. Hence, it is necessary to identify emerging risks for drinking water production at an early stage and to assess and prioritise emerging risks to the production and supply of safe drinking water.
Project PS-Drink was initiated to enable a more proactive, integrated and systematic assessment of emerging drinking water contaminants. The project is a collaboration between RIVM, Utrecht University and Delft University of Technology. The objective was (1) to develop an integrated methodology for the systematic identification, assessment and prioritisation of emerging chemical and microbial risks to the production and supply of safe drinking water and (2) to develop effective strategies to communicate such risks. The project started in the summer of 2016 and will end by December 2020.
Results of PS-DRINK
Results of PS-DRINK
Current risk governance of emerging drinking water contaminants: areas for improvement
Only limited information is available on if, and how, scientific information is implemented in current policy approaches. The opportunities for science to contribute to the policy of emerging contaminants in drinking water have, therefore, not yet been identified. Current approaches to risk governance of emerging chemical contaminants in drinking water and drinking water resources in the Netherlands, Germany, Switzerland and the state of Minnesota were analysed. The analysis led to the conclusion that systematic analytical screening of information sources as product registration databases, news media and scientific literature is essential for the timely identification of emerging contaminants to drinking water quality. The analysis was published in a scientific paper.
In the second stage of the project, a new early warning system was developed based on the systematic search of the universal scientific literature for articles reporting the first detection of a contaminant in the aquatic environment. It is known that it takes about 15 years from the first scientific publication about a contaminant to a peak number of publications. This peak is in many cases associated with regulatory or mitigation actions, meaning a late response. Screening the scientific literature for early signals of new contaminants, by using literature mining as an early warning system, can be effective to shorten the period of emerging concern.
The developed identification methodology was published in a scientific paper. The effectiveness for early warning purposes of screening the scientific literature to direct sampling campaigns for both microbial and chemical contaminants was also validated with a sampling campaign. The results of the sampling campaign were also published in a scientific paper.
A decision support tool was developed for the integrated assessment of emerging chemical and microbial drinking water contaminants. This decision support tool was developed using the input of 47 Dutch risk assessors, drinking water experts and members of responsible authorities. With the decision support tool risk scores can be quantified for chemical and microbial contaminants for which evidence of their hazard and exposure potential is scarce. The decision support can be used by researchers to assist policymakers in prioritising action on those emerging contaminants that pose the highest potential risk to humans via drinking water.
The development of the decision support tool was published in a scientific article. In addition, the added value of integrating climate change criteria in a prioritisation method for emerging risks to drinking water quality was assessed in a parallel study. The results implicated that the integration of climate change in a prioritisation method for emerging risks to Dutch drinking water quality does have added value. The integration can support futureproof policy-making and promote proactive identification of emerging contaminants of potential high concern.
Effective strategies for communication on emerging risks
For the quality of their drinking water, consumers rely on science to identify and monitor hazards, determine health risks and inform them about potential health threats and on policymakers to regulate these threats. Frequently, consumers are confronted with information stating that a hazardous substance has been detected in drinking water resources but that this presence does not constitute a risk to public health because the doses do not exceed the safety levels. While experts may be familiar with such statements, public understanding of these risk statements generally does not correspond with the scientific interpretation. In this study, we tested the effectivity of textual and visual risk communication materials about emerging contaminants in drinking water. Information needs of consumers were identified using interviews and questionnaires. Based on the identified information needs, an existing web text was revised and tested in a consumer panel. Also, an accompanying infographic explaining the risk assessment process was developed and tested.
The research performed on finding effective strategies for communication on emerging drinking water risks was published in a scientific article.
IWA Project Innovation Awards
PS-DRINK has made it to round two of the International Water Association Project Innovation Awards. These awards recognise and promote excellence and innovation in water management, research and technology and are awarded biennially at the IWA World Water Congress & Exhibition.
Over the duration of the project, four workshops with stakeholders from industry, research and policy were organised. These workshops aimed to keep stakeholders actively involved in order to facilitate the take-up of the developed methodologies. Reports of the workshops are available in Dutch.
The research performed within the PS-DRINK project was presented during the following international conferences:
- IWA Regional Young Water Professionals Conference Benelux, Ghent, 2017
- Water and Health conference, The Water Institute, Chapel Hill, United States of America, 2018
- SETAC Europe 29th annual meeting, Helsinki, Finland, 2019