The Outstanding Achievements in Environmental Science & Technology Award recognizes change makers, whose research and service contributions to the fields have substantially supported improvements in human health and/or the environment.
Please join Environmental Science & Technology and Environmental Science & Technology Letters in warmly congratulating winners of the 2023 award: Prof. Dr. Beate Escher, Head of Department of Cell Toxicology, Helmholtz Centre for Environmental Research, and Prof. Dr. Urs Von Gunten, Head of Competence Center for Drinking Water, Eawag.
Professor Beate Escher
Professor Beate Escher is internationally recognized for her work on chemical pollution in the environment. She pioneered the field of water quality assessment by addressing complex mixtures of chemical pollutants using in vitro bioassays. Beate Escher obtained her PhD 1995 and her Habilitation in 2002 at the Swiss Federal Institute of Technology ETH, Zürich, Switzerland.
Presently, she is head of the Department of Cell Toxicology at the Helmholtz Centre for Environmental Research in Leipzig, Germany, and professor at the Eberhard Karls University Tübingen, Germany. She is also lecturer at ETHZ, Switzerland, holds an honorary professorship at the University of Queensland and an adjunct professorship at Griffith University, Australia. She was Associate Editor with Environmental Science & Technology from 2012 to 2020 and is member of the Board of Reviewing Editors at Science.
Describe your current area of research (or areas of interest).
My interest are complex mixtures of organic pollutants in the environment and people and how we can identify and monitor these mixtures and assess their risk. We develop methods for unbiased extraction from complex matrices, including wildlife and human tissue and use in vitro bioassays to complement chemical analysis as tools for identification of chemical exposure and for monitoring success of remediation and intervention to reduce chemical exposure.
In my first two Environmental Science & Technology papers in 1996, I used octanol- and membrane-water partitioning of ionizable organic chemicals as well as time-resolved kinetic spectrometry to explain a fundamental toxicological problem, i.e., how to differentiate different mechanisms of toxicity on the example of uncoupling and inhibition of energy transduction. This work ultimately led to toxicokinetic and toxicodynamic models in ecotoxicology and later human toxicology.
Today we use in vitro methods and models rooted in in the mechanistic thinking of adverse outcome pathways not only to investigate modes of toxic action but also as tools for chemical risk assessment as well as environmental monitoring and biomonitoring– including assessment of engineered systems for their capacity to eliminate environmental contaminants from wastewater.
What have been some of the key influences that have shaped how your career has developed?
As a synthetic organic chemist, I was always fascinated by toxicology and had a passion for the environment but my first job in an animal testing facility motivated me to think about ways to understand how chemicals act without harming our furry friends. Although my subsequent research has always evolved around in vitro toxicology, I spent most of my formative years in the Environmental Organic Chemistry group at ETH Zürich and Eawag, where I was immersed in a creative and open research environment with little toxicology expertise but the common goal of understanding environmental processes from the perspective of the chemicals.
This led me to apply concepts of environmental chemistry such as multimedia fate models and equilibrium partitioning concepts to mechanistic toxicology. I owe immensely to my mentors Rene Schwarzenbach, John Westall and Joop Hermens who are not only amazing teachers but also inspiring role models and to the numerous colleagues, technicians, students and postdoc I had the privilege to collaborate with.
What do you consider some of the most important highlights from your career so far?
In 2005, during a sabbatical at the University of Queensland, I was doing my first field study. I realized that “my” in vitro tools have many practical applications and how rewarding it is to collaborate with practitioners. Eventually I moved my lab to Australia to focus entirely on the use of bioanalytical tools in water quality assessment and environmental monitoring. Since then, we have expanded to applications in chemical risk assessment, human and wildlife biomonitoring.
What is your advice for young investigators?
Follow your heart and do what you are passionate about even if it is not necessarily the mainstream now. If you believe in it, it will become relevant one day. Today, young researchers are put under immense stress to perform and at the same time be “out there” at meetings and on social media. While this can be rewarding short term, in the long term, excellence builds on scientific quality. And to achieve quality is hard work – numerous replicates, always scrutinizing for artefacts and learning from failure.
Professor Urs Von Gunten
Professor Urs von Gunten is a global leader in oxidation chemistry. He has made significant contributions to both the academic developments of this field and its translation in practice. Professor von Gunten has specifically advanced the fundamental understanding of ozonation processes, mechanistic studies of halogen-containing disinfection byproducts, oxidation processes for CEC abatement, and an understanding of the role of dissolved organic matter in oxidative water treatment.
A hallmark of his work lies in connecting fundamental reaction chemistry with practical drinking water applications. Professor von Gunten’s pioneering studies developed mechanistic insights into the pathways and kinetics of the formation of bromate, which can be used to mitigate bromate during oxidation processes with ozone. His mechanistic studies on iodate formation and mitigation of iodo-organic compounds remain a benchmark for oxidative water treatment. His studies on the development and application of the ratio of hydroxyl radical to ozone exposures have become the standard practice for characterizing ozone treatment of water and wastewater and then optimizing drinking water and wastewater oxidation processes in practice.
Professor von Gunten’s contributions and strategies for protecting public health and the environment are radically changing the way wastewater treatment plants operate, with new regulations requiring use of powdered activated carbon or advanced oxidation processes to treat CECs before discharge to surface waters.
Describe your current area of research (or areas of interest).
My current research deals with oxidative transformation processes in water and wastewater treatment. The main focus is on kinetic and mechanistic studies of the abatement of micropollutants, reactions with halide ions (bromide, iodide) and dissolved organic matter (DOM). Whereas with micropollutants and halide ions fundamental information on transformation reactions can be gained by various methods such as LC-MS, GC-MS and ion chromatography, the reactions of chemical oxidants with DOM are more difficult to assess by standard methods. To this end we have developed novel methods which include oxidative titrations and measurement of the electron donating capacity to characterize the DOM in terms of its oxidant reactivity and the potential for the formation of disinfection byproducts.
What have been some of the key influences that have shaped how your career has developed?
During my studies in chemistry at ETH in Zürich I had to attend a lecture “Chemistry and the Environment”, where I heard about geochemistry and chemical pollution. Since I was already very much interested in the environment, I decided to take a career path in environmental chemistry, rather than becoming a synthetic organic chemist as most of my colleagues. The deceased Walter Schneider became my PhD advisor for a project on iron cycling in lakes. He roused my interest in natural chemical processes in the environment and let me do my PhD thesis independently.
Later, I moved to Eawag, where I did a postdoc with Jürg Zobrist and later worked with the deceased Jürg Hoigné who both taught me solid and quantitative environmental chemistry. I had the chance to take over Jürg’s research field of oxidative water treatment at Eawag and I am still very much interested in this. Eawag is a melting pot of knowledge and research ideas and I benefited tremendously from this environment with many collaborative project over the years. During my career I also met the late Clemens von Sonntag and I profited enormously from his vast knowledge by co-authoring a book on ozone chemistry with him.
My wife, Birgit, and my son, Timo, also contributed enormously to my career by their unconditional support and inspiration during the last decades.
What do you consider some of the most important highlights from your career so far?
The most important step in my career was my employment at Eawag more than 30 years ago. It opened me so many options nationally and internationally, which were the main drivers for my career. It provided me with stable base funding and high-quality competitive funding from the Swiss EPA and the Swiss National Science Foundation, which allowed me to build up a long-term research line on oxidation chemistry.
My appointment as a professor at EPFL was another important career step, which enabled me to expand my teaching and research. The many collaborations with researchers at Eawag and EPFL were crucial for the advancement of my research, and I always enjoyed these scientific but also personal interactions very much.
What is your advice for young investigators?
I was always fascinated to combine fundamental research with applications. This was highly motivating for me and my research team and allowed to satisfy the scientific curiosity, while I could help solve some of the environmental problems. This was also possible by many collaborations with practice, where the findings of my research team could be implemented.
