Research Area: Water Quality and Health (QUALITY)
Research Line: Microbiological and chemical quality monitoring
Water quality can be affected by a wide range of pollutants and pathogens of considerably different nature and properties. Therefore, a wide range of different methods for sample preparation, clean-up and analysis is necessary. However, for many pollutants and pathogens either analytical methods for quantification have not been established or existing methods have severe drawbacks in terms of time required, lacking sensitivity, or limited routine applicability. Therefore, the development of new or the adaptation of existing methods to overcome these drawbacks is still an important issue. The driving hypothesis is that the analytical window is still too narrow to allow for a comprehensive assessment of chemical and microbiological burdens and risks.
Hyphenation of liquid and gas chromatography to organic and inorganic mass spectrometry will be the major tools used for the development of new quantitative methods for chemical substances, e.g. for polar compounds and transformation products from the use of new treatment technologies. On-line and in-situ methods that are in particular of importance for control of water quality in water networks will also be addressed. Depending on demands stemming from drinking water guidelines, development of further methods for the improved detection of radioactivity or specific radionuclides will be continued as well. Integrative sensors for water quality as well as optimised sensor selection and placement in e.g. raw water and networks are cross-cutting issues that will be pursued in close connection with the research line on maintenance and operation of water supply systems.
A further research interest is to locate and quantify biofilms including possible abiotic contribution to deposit formation. In extended water systems, two options are given for that purpose: i) systematic water sampling for identification of contaminating sources, and, ii) surface sampling and observation with devices allowing for on-line, in-situ, non-destructive and real-time detection of deposit formation kinetics. Both options will be followed in future research at IWW.
A particularly interesting aspect of microbiological water quality is the consideration of viable but non-culturable (VBNC) pathogens. In the VBNC state, they are not captured by cultural methods designed for their detection but can re-gain their viable and, quite probably, infectious state. Here, the systematic introduction of culture-independent molecular biological methods such as fluorescence-in-situ-hybridization (FISH), live-dead system, PMA with qPCR, direct viable count, and the use of fluorescently labelled enzyme substrates is planned for detection of the proportion of VBNC cells in a population.
Research Line: Water hygiene and toxicology
Safe water systems (drinking, bathing, urban water, waste water re-use for different applications) are essential for the health and well-being of people. Research will address the interaction of pathogens and biofilms including pipe material, conditions (e.g. temperature), other microorganisms and nutrients. This is an important issue in water distribution systems and household installations where pathogens may impose risks for the health of consumers. Standard analytical methods will be complemented by molecular methods especially adapted for biofilms. In close connection with the research line climate change and energy efficiency the role of e.g. changing temperature on the occurrence of pathogens will be investigated. Risk management of pathogens and chemical pollutants in surface water with the aim to secure raw water resources and recreational use will also be addressed.
Furthermore, hygienic aspects of technical water systems are of increasing importance. Process waters in cooling towers, paper mills, production lines and other industrial environments can contain considerable amounts of pathogens to which the personnel of such plants can be exposed. Technical rules and liability of the companies will require more and more focus on hygiene in such water systems. In order to meet these requirements it will be necessary to i) develop reliable and fast detection methods, ii) to improve water treatment and, iii) to survey the efficacy and generate early warning systems.
Toxic and hazardous substances in drinking water may have an impact on human health either by personal consumption or by humans being in contact with water. Our research in this field will focus on toxicological in vitro assessment of those substances in water by testing of trace and emerging pollutants with various toxicological tests (e.g. genotoxicity, mutagenicity and estrogenicity assays). The in-vitro cultivation of mammalian cells provides a suitable and sensitive testing system for the analysis of a hazardous potential of substances and compounds. The results of toxicological studies are being used to derive proposals for precautional or limit values for drinking water, and remediation measures. The potential of combining classical toxicological methods with artificial neural networks or QSAR (quantitative structure-activity relationship) approaches will be explored.