Kathrin Fenner

Research Interests

• Environmental fate modeling of transformation products
• Prediction of biodegradation routes and rates of organic chemicals
• Assessment of transformation products of pesticides, biocides and pharmaceuticals in surface waters
• Analytical identification of transformation products
• Polyparameter linear free energy relationships to predict sorption
• Ecotoxicity of transformation products
• Methods for chemical risk assessment

CV

at present	Visiting researcher at the Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, St. Paul, USA
2004-2006	Oberassistentin (Research assistant professor), Institute of Biogeochemistry and Pollutant Dynamics, ETH Zürich, Zürich, Switzerland & Department of Environmental Chemistry, Eawag, Dübendorf, Switzerland
2002-2004	Post-doctoral research fellow, Department of Environmental Sciences, ETH Zürich, Zürich, Switzerland & Department of Environmental Chemistry, Eawag, Dübendorf, Switzerland
2001-2002	Post-doctoral research fellow, Department of Chemistry and Applied Biosciences, ETH Zürich, Zürich, Switzerland
2001	Visiting research scholar, Lawrence Berkeley National Laboratory, Environmental Energy Technology Division, USA
1997-2001	Scientific collaborator and PhD student, Department of Chemistry and Applied Biosciences, ETH Zürich, Zürich, Switzerland
1992-1997	Diploma studies in Chemistry, University of Zurich, Switzerland

Research statement

Assessing the risk of exposure to chemical pollutants in aquatic resources such as groundwater and surface waters is one of the major challenges in human health and environmental risk assessment. The fact that many contaminants degrade into structurally closely related transformation products, which may exhibit similar toxicity and persistence as the parent compounds, adds to that challenge. My research program uses a combination of experimental, modeling and statistical approaches to advance water quality and chemical risk assessment with respect to transformation products of chemical pollutants. My research focuses on the following four areas in particular.

Identification of transformation products in aquatic environments -

Identification of transformation products in aquatic resources is hampered by (i) a lack of analytical standards for most transformation products, (ii) little knowledge on the exposure potential and fate of transformation products, and (iii) a lack of information on possible breakdown products. In my group we therefore combine process-based environmental fate models to generate initial target lists of transformation products with high exposure potential with high-resolution mass spectrometry into an efficient screening procedure to identify transformation products that are prevalent in water resources.

Prediction of biodegradation pathways and rates -

Current tools to predict biodegradation half-lives produce highly uncertain results and available pathway prediction tools suffer from combinatorial explosion due to a lack of methods to prioritize possible pathways. In my research I apply thermodynamic efficiency considerations and bioinformatics tools such as substructure search algorithms and training against molecular descriptors to prioritize possible pathways predicted by the UM-PPS (University of Minnesota Pathway Prediction System). Future research in my group will encompass the validation of these predictions through biodegradation studies in sewage sludge and soil.

Hazard and risk assessment of transformation products –

The goal of this aspect of my research is to develop models and indicators to predict and assess the environmental fate of transformation products. Indicators tailored for the assessment of transformation products include joint persistence, relative aquatic concentrations and mixture risk quotients. In collaboration with the ecotoxicologists at Eawag we are currently developing methods to estimate mixture toxicity of transformation products and their parent compound, using the strong structural resemblance between parent compounds and what is known about parent toxicity as a guiding principle. Other efforts go towards developing a sewage treatment plant model that can account for the dynamic formation and fate of transformation products.

Sorption behavior of complex and ionic contaminants –

Polyparameter-LFERs have been shown to overcome many limitations of current models to predict partitioning, especially for polar and structurally complex contaminants, while being able to predict partitioning between a wide range of environmental phases. In our research group we are working with a high-throughput, HPLC-based methodology to measure molecular interaction parameters (solute descriptors) for neutral pesticides and pharmaceuticals to be used in pp-LFERs. Currently we are modifying this system to extend its ability to investigate the sorption behavior of ionic species of complex contaminants.

Selected Projects:

• KoMet - Combined modeling and measurement approach for the identification of relevant transformation products in water resources [...]
  
• ERAPharm (Environmental Risk Assessment of Pharmaceuticals) [...]
• Prioritization of relevant transformation products of micropollutants [...]
• Predicting sorption properties of neutral and ionic complex contaminants [...]
  

Selected Publications

Schneider, M.K.; Stamm, C.; Fenner, K. (2007). Selecting Exposure Scenarios for Veterinary Pharmaceuticals at a European Scale. Environmental Science and Technology, in press.

Fenner, K.; Lanz, V.; Scheringer, M.; Borsuk, M. (2007). Relating Atrazine Degradation Rate in Soil to Environmental Conditions: Implications for Global Fate Modeling. Environmental Science and Technology 41(8), 2840-2846.

Gasser, L.; Fenner, K.; Scheringer, M. (2007). Indicators for the Exposure Assessment of Transformation Products of Organic Micropollutants. Environmental Science and Technology 41(7), 2445-2451.

Fenner, K.; Canonica, S.; Escher, B.I.; Gasser, L.; Spycher, S.; Tülp, H.C. (2006). Developing methods to predict chemical fate and effect endpoints for use within REACH. Chimia 60, 683-690.

Schwarzenbach, R.R.; Escher, B.I.; Fenner, K.; Hofstetter, T.B.; Johnson, C.A.; von Gunten, U.; Wehrli, B. (2006). The Challenge of Micropollutants in Aquatic Systems. Science 313(5790), 1072-1077.

Fenner, K.; Escher, B. (2006). Umweltchemie und Ökotoxikologie im Spannungsfeld von Wissenschaft und Praxis, GAIA 15(2), 121-126.

Chèvre, N.; Loepfe, C.; Singer, H.; Stamm, C.; Fenner, K.; Escher, B. (2006). Including Mixtures in the Determination of Water Quality Criteria for Herbicides in Surface Water. Environmental Science and Technology 40(2), 426-435.

Arp, H.P.H; Fenner, K.; Schmidt, T.C. (2005). Predicting Methyl tert-Butyl Ether, tert-Butyl Formate, and tert-Butyl Alcohol Levels in the Environment Using the Fugacity Approach. ”. Environmental Science and Technology 39(9), 3237-3244.

Knacker, T.; Duis, K.; Ternes, T.; Fenner, K.; Escher, B.; Schmitt, H.; Römbke, J.; Garric, J.; Hutchinson, T.; Boxall, A.B.A (2005). The EU-project ERAPharm – Incentives for the Further Development of Guidance Documents? Environmental Science and Pollution Research 12(2), 62-65.

Boxall, A.B.A.; Sinclair, C.J.; Fenner, K.; Kolpin, D.; Maund, S.J. (2004). When Synthetic Chemicals Degrade in the Environment. Environmental Science and Technology 38(19), 368A-375A.

Fenner, K.; Scheringer, M.; Hungerbühler, K. (2003). Joint Persistence of Transformation Products in Chemicals Assessment: Case Studies and Uncertainty Analysis. Risk Analysis 23, 35-53.

Fenner, K.; Kooijman, C.; Scheringer, M.; Hungerbühler, K. (2002). Including Transformation Products into the Risk Assessment for Chemicals: The Case of Nonylphenol Ethoxylate Usage in Switzerland. Environmental Science and Technology 36, 1147-1154.

Fenner, K.; Scheringer, M.; Hungerbühler, K. (2000). Persistence of Parent Compounds and Transformation Products in a Level IV Multimedia Model. Environmental Science and Technology 34, 3809-3817.