EESS talk on "Characterization of Disinfection Processes as Barriers to the Dissemination of Antibiotic Resistance Genes in Water, Wastewater, and Healthcare Settings"
Event details
| Date | 11.04.2017 |
| Hour | 12:15 › 13:15 |
| Speaker |
Dr Michael Dodd, Assistant professor, Civil & Environmental Engineering, College of Engineering, University of Washington, Seattle (USA), visiting professor @LCE Short biography: Dr. Michael Dodd is an Associate Professor in the Department of Civil and Environmental Engineering and an Adjunct Associate Professor in the Department of Environmental and Occupational Health Sciences at the University of Washington. He received a B.S. in Civil Engineering (2001) and M.S. in Environmental Engineering (2003) from the Georgia Institute of Technology, Ph.D. in Environmental Sciences from the Swiss Federal Institute of Technology in Zurich (2008), and was a postdoctoral fellow in the Environmental Engineering Program of Yale University from 2008-2009, prior to beginning his appointment at the UW in 2009. Dr. Dodd’s research interests focus on the characterization of chemical and photochemical redox processes in engineered and natural aquatic systems, particularly with regard to their application in optimizing pollutant and pathogen elimination during water and wastewater treatment. Dr. Dodd has received a number of honors for his work, including an NSF CAREER Award, the CH2M Hill/AEESP Outstanding Doctoral Dissertation Award from the Association of Environmental Engineering and Science Professors, the ETH Medal from the Swiss Federal Institute of Technology-Zurich, and Excellence in Review and Outstanding Reviewer awards from Environmental Science and Technology and the ASCE Journal of Environmental Engineering. Dr. Michael Dodd is an Associate Professor in the Department of Civil and Environmental Engineering and an Adjunct Associate Professor in the Department of Environmental and Occupational Health Sciences at the University of Washington. He received a B.S. in Civil Engineering (2001) and M.S. in Environmental Engineering (2003) from the Georgia Institute of Technology, Ph.D. in Environmental Sciences from the Swiss Federal Institute of Technology in Zurich (2008), and was a postdoctoral fellow in the Environmental Engineering Program of Yale University from 2008-2009, prior to beginning his appointment at the UW in 2009. Dr. Dodd’s research interests focus on the characterization of chemical and photochemical redox processes in engineered and natural aquatic systems, particularly with regard to their application in optimizing pollutant and pathogen elimination during water and wastewater treatment. Dr. Dodd has received a number of honors for his work, including an NSF CAREER Award, the CH2M Hill/AEESP Outstanding Doctoral Dissertation Award from the Association of Environmental Engineering and Science Professors, the ETH Medal from the Swiss Federal Institute of Technology-Zurich, and Excellence in Review and Outstanding Reviewer awards from Environmental Science and Technology and the ASCE Journal of Environmental Engineering. |
| Location | |
| Category | Conferences - Seminars |
Abstract:
Disinfection processes play an important role in minimizing transport of viable antibiotic resistant bacteria (ARB) within environmental systems and communities. However, recent work suggests that antibiotic resistance genes (ARGs) associated with ARB cells may in some cases “survive” disinfection and remain capable of disseminating resistance traits to non-resistant bacterial populations via horizontal gene transfer processes (e.g., natural transformation). In order to evaluate this possibility, we are employing a combination of real-time quantitative polymerase chain reaction (qPCR) and culture-based DNA activity assays to determine the effectiveness of disinfectants commonly used in (waste)water and healthcare practice for not only inactivating ARB cells, but also degrading and deactivating (i.e., eliminating the biological activities of) ARGs associated with extra- and intracellular bacterial DNA. Our measurements of ARG degradation and deactivation kinetics indicate that for all disinfectants investigated, ARG degradation and deactivation significantly lag inactivation of ARB cells (i.e., ARGs do indeed “survive” disinfection), and that substantially higher disinfectant exposures are required to achieve ARG degradation and deactivation than to achieve inactivation of ARB cells themselves. For some disinfectants (e.g., HOCl, O3, UV, H2O2), ARG degradation and deactivation may be accomplished at disinfectant exposure levels achievable under practical treatment conditions, whereas for others (e.g., NH2Cl, ClO2, phenol, ethanol), appreciable degradation or deactivation of ARGs is not expected even at the most extreme treatment conditions likely to be applied in practice. These findings could have significant implications for selection, design, and operation of disinfection processes, and will be discussed with respect to opportunities for optimizing, monitoring, and predicting ARG degradation and deactivation during water, wastewater, and healthcare disinfection.
Disinfection processes play an important role in minimizing transport of viable antibiotic resistant bacteria (ARB) within environmental systems and communities. However, recent work suggests that antibiotic resistance genes (ARGs) associated with ARB cells may in some cases “survive” disinfection and remain capable of disseminating resistance traits to non-resistant bacterial populations via horizontal gene transfer processes (e.g., natural transformation). In order to evaluate this possibility, we are employing a combination of real-time quantitative polymerase chain reaction (qPCR) and culture-based DNA activity assays to determine the effectiveness of disinfectants commonly used in (waste)water and healthcare practice for not only inactivating ARB cells, but also degrading and deactivating (i.e., eliminating the biological activities of) ARGs associated with extra- and intracellular bacterial DNA. Our measurements of ARG degradation and deactivation kinetics indicate that for all disinfectants investigated, ARG degradation and deactivation significantly lag inactivation of ARB cells (i.e., ARGs do indeed “survive” disinfection), and that substantially higher disinfectant exposures are required to achieve ARG degradation and deactivation than to achieve inactivation of ARB cells themselves. For some disinfectants (e.g., HOCl, O3, UV, H2O2), ARG degradation and deactivation may be accomplished at disinfectant exposure levels achievable under practical treatment conditions, whereas for others (e.g., NH2Cl, ClO2, phenol, ethanol), appreciable degradation or deactivation of ARGs is not expected even at the most extreme treatment conditions likely to be applied in practice. These findings could have significant implications for selection, design, and operation of disinfection processes, and will be discussed with respect to opportunities for optimizing, monitoring, and predicting ARG degradation and deactivation during water, wastewater, and healthcare disinfection.
Practical information
- General public
- Free
- This event is internal
Organizer
- EESS - IIE
Contact
- Prof. Tamar Kohn, LCE