Abstract: 
Current treatment assessments and water quality monitoring that rely only on measuring the reduction of target contaminant concentrations are insufficient because they do not consider the complex and broader risks that specific or mixtures of contaminants and their transformation products pose to the environment and human health. This poses a pressing need for a breakthrough in toxicity-assessment technology because the currently available methods are neither feasible nor sufficient to provide the timely information needed for regulatory decision-making and technology development to eliminate these threats. This study developed a novel, feasible and cost-effective quantitative toxicogenomics-based toxicity assessment platform for high-throughput and effective chemical hazardous identification and environmental toxicity monitoring. We systematically optimized the assay platform, evaluated its robustness and performance, validated the assay output and demonstrated its wide applications.  Compared with other main stream “omics’ technologies, the proposed method greatly improves the feasibility and cost effectiveness as a result of its much simpler, faster, and more reliable assay procedures. Furthermore, it provides multi-dimensional transcriptional level effect information with a temporal dimension and therefore can more accurately reflect the chemical-induced time-dependent cell responses with higher sensitivity and specificity. We demonstrated that information-rich toxicogenomic data are powerful for evaluating toxic effects, understanding toxicity mechanisms, and obtaining pollutant-specific molecular fingerprints for compound /sample classification and identification. One of the main challenges in applying toxicogenomics for environmental monitoring is the lack of a quantitative method to convert the toxicogenomic information into a readily usable and transferable format that can be incorporated into ecological risk assessment and regulatory framework. We proposed a new transcriptional effect level index (TELI) that exhibited a dose-response relationship and allowed for linking the transcriptional level effects to conventional toxicity endpoints.  In addition, we pioneered quantitative molecule toxicity modeling within the context of toxicogenomics and paved the road for further mixture toxicity identification and prediction. Cross-species comparison and extrapolation is another key aspect related to predictive and mechanistic toxicity assessment to overcome the limitation of data generation ability. We have compared three different species for variety of compounds and demonstrated the possibility of cross-species extrapolation with stress-response pathway ensemble based toxicity assessment. Finally, we demonstrated successful application of the novel assay for mechanistic CECs toxicity assessment, whole effluent toxicity monitoring and risk-based water treatment technologies efficacy evaluation. 
                            
Biography:
Dr. April Gu is currently professor at Civil and Environmental Engineering Department, affiliated faculty and track leader for Interdisciplinary Bioengineering Program within the College of Engineering and affiliated faculty for Biotechnology Program with Bouve College of Health Sciences at Northeastern University in Boston. Dr. Gu received her B.S. in Environmental Engineering and Science from Tsinghua University in Beijing, China and a Ph.D. in Civil and Environmental Engineering, jointly in Microbiology, from the University of Washington, US. Her expertise and area of research interest include: 1) biotechnology for water and wastewater treatment and biological nutrient removal; 2) risk-based water quality monitoring and toxicity assessment; 3) biosensors and nano-biosensors; 4) global phosphorus cycling and bioavailability of nutrients in natural ecological systems. She has led and participated over 30 research projects funded by various agencies including NSF, DOE, EPA, WERF and NIEHS. She has over 120 journal, conference and other technical publications and given 220 presentations at conference and workshops, including 70 invited talks. She and her students have received a number of national awards including NSF CAREER award, SETAC Endowment Travel Award, National Pathfinder Award for Creativity (HDR Inc.), SETAC Global Best Student Paper Award and, IEEE Yong researchers Forum Award, ACS Outstanding Presentation Merit Award. She received the Søren Buus Outstanding Research Award from Northeastern University in 2011 and elected to be COE faculty Fellow in 2014. She was invited speaker for Gordon Conference-Drinking Water Disinfection Byproducts 2017, Gordon Conference -Environmental Nanotechnology 2013, and Gordon Conference – Water Science in 2012.  She was elected to be WEF Fellow in 2017. She was also elected to serve on the Board of Directors for AEESP in 2017. 

Hosted by Prof. Na Wei, Department of Civil and Environmental Engineering and Earth Sciences