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The Smith Research Group evaluates environmental biotechnologies to improve our water infrastructure by recovering resources such as energy, nutrients, and water from waste streams. Our research encompasses process engineering, microbial ecology, molecular chemistry and sustainability assessments to design and develop new and emerging processes for water and wastewater treatment. The Smith Research Group spans multiple research areas including, but not limited to, wastewater-based epidemiology, antibiotic resistance, biofilms as biosensors & tools for greenhouse gas mitigation, and PFAS biotransformation. To learn more about each of these research areas as well as any featured collaborations, please see below. 

Wastewater-Based Epidemiology​

Wastewater-based epidemiology (WBE) has emerged as a powerful tool for monitoring public health by analyzing wastewater samples for the presence of biomarkers, pathogens, and genetic material associated with diseases. By studying the composition of wastewater and the dynamics of biological contaminants, our research aims to develop innovative methods and technologies for early detection, surveillance, and response to potential disease outbreaks.

 

Dedicated to advancing the field of WBE to aid in the mitigation of biological contaminants and the tracking of potential disease outbreaks, the Smith Research Group was funded by the university to form the USC Campus Wastewater Surveillance Team. To enhance their research and expand their sampling capabilities, USC has installed 26 different wastewater sampling stations campus-wide, as the team is dedicated to utilizing WBE to promote campus-wide public health improvements. These sampling stations are used to investigate community health trends by analyzing pathogens and biomarkers, their fate and transport, and how this wastewater data correlates with clinical data.

 

Through our interdisciplinary approach, combining environmental engineering, microbiology, and epidemiology, our lab group seeks to contribute to the development of effective strategies to mitigate biological contaminants and enhance public health surveillance, ultimately enabling timely interventions to protect and safeguard human populations from the onset of potential diseases. Currently, the USC Campus Wastewater Surveillance Team is led by PhD student Michael Saldana and is made up of four graduate and undergraduate student research assistants.

In Depth: Wastewater & Disease

This April, Dr. Smith was interviewed by LA FOX11's Hal Eisner, discussing the various ways in which our lab's research uses wastewater sampling and treatment as a service to public health. This includes techniques used by our lab's wastewater surveillance team, how testing works and why it's important, as well as antibiotic resistant genes and their impacts. For more information, see LA FOX11's article here.

April 2023
Antibiotic Resistance

Dedicated to advancing the understanding of antibiotic resistance fate and proliferation in wastewater treatment, the Smith Research Group's research has a particular focus on investigating the dynamics of antibiotic resistance genes (ARGs) in anaerobic digestion processes. Antibiotic resistance has become a global health concern, and the role of wastewater treatment plants as potential hotspots for the dissemination of ARGs is increasingly recognized. By employing a multidisciplinary approach that integrates microbiology, molecular biology, and environmental engineering, our research aims to elucidate the mechanisms governing the fate of ARGs in anaerobic digestion systems. We seek to identify the factors influencing ARG persistence, transformation, and dissemination within microbial communities under anaerobic conditions. By shedding light on these processes, our laboratory group strives to develop effective strategies to mitigate the spread of antibiotic resistance and enhance the performance of wastewater treatment plants in removing ARGs. Through our investigations, we aim to contribute to the development of sustainable and safe wastewater treatment practices that protect human health and the environment from the risks associated with antibiotic resistance.

The Smith Research Group is expanding on these studies as a part of the new USC ReWater Center (Water Reuse and Resource Recovery Center) supported by the U.S. Army ERDC-CERL. The center will be dedicated to achieving constituent removals necessary to meet potable reuse regulations, recovering resources from wastewater and residual streams, and reducing energy requirements for sustainable wastewater reclamation. This center is just one part of the newly announced Water Reuse Consortium, in which USC Viterbi's Environmental Engineering Water Labs play a vital role, and the Smith Research Group will be leading research in environmental biotechnologies for resource recovery, microbial ecology with an emphasis on antimicrobial resistance, and contaminants of emerging concern.

Biofilms
Counter-diffusional biofilm process

Biofilms are complex microbial communities that adhere to surfaces and form structured multicellular aggregates. In anaerobic environments, these biofilms play a crucial role in various biotechnological processes, including wastewater treatment, biogas production, and pollutant degradation. To investigate biofilm parameters and capabilities, our lab utilizes engineered biotechnology, specifically microbial electrolysis cells and membrane biofilm reactors (MBfRs). The Smith Research Group uses microbial electrolysis cells to investigate bioelectric biofilms for the development of innovative biosensors capable of detecting and monitoring environmental parameters or contaminants, while MBfRs are utilized for metabolic studies which require a hospitable environment for a counter-diffusional biofilm process enabling the simultaneous mitigation of aqueous and gaseous contaminants.

Using MBfRs, the Smith Research Group explores the potential of biofilms as a sustainable approach for mitigating greenhouse gas emissions, particularly carbon dioxide, nitrous oxide and methane. This research not only focuses on functions of the biofilm, but microbial metabolisms that can enhance the mitigation process via

investigating bacterial and archaeal greenhouse gas consumption. In collaboration with USC Dornsife PI's Cameron Thrash and Jan Amend, Dr. Smith is a lead PI for the USC Microbial Greenhouse Gas Consumption Research Center. Members of the Smith Research Group who conduct research within this Center use analytical chemistry, molecular biology, and bioinformatics to identify and grow new microbes capable of converting greenhouse gases into innocuous waste products. Many microorganisms can breathe greenhouse gases, thereby destroying them, and this research aims to discover and harness the power of naturally occurring microbes in the oceans and on land that consume the three most harmful greenhouse gases — carbon dioxide, methane, and nitrous oxide. By investigating the formation, composition, and functionality of aerobic and anaerobic biofilms, our lab group strives to unlock their full potential for environmental monitoring and greenhouse gas mitigation, paving the way for more efficient and sustainable biotechnological applications.

PFAS Biotransformation

Per- and polyfluoroalkyl substances (PFAS) have recently been gaining attention as contaminants of emerging concern. These man-made chemicals are used in a wide range of consumer and industrial products, and break down very slowly resulting in sizable accumulation in the environment and human tissue.

The Smith Research Group is dedicated to investigating the biotransformation of PFAS in anaerobic digestion processes and the cycling of PFAS in water treatment. This research revolves around understanding the underlying mechanisms involved in PFAS degradation by microbial communities under anaerobic conditions. Through our interdisciplinary approach, combining microbiology, environmental chemistry, and process engineering, we aim to elucidate the factors influencing the efficiency of PFAS removal in anaerobic digesters and identify strategies to enhance their biotransformation.

 

Additionally, we are actively studying the fate of PFAS and its byproducts during water treatment processes, aiming to develop innovative techniques for the complete removal of residual PFAS from treated water. By conducting cutting-edge research in this field, our group seeks to contribute to the development of sustainable and efficient solutions for PFAS remediation and environmental protection.

USC's 2023 Research and Innovation President's Sustainability Initiative Award was awarded to Dr. Smith and his collaborators at USC Keck School of Medicine for their current project: PFAS ACT: Addressing the PFAS Drinking Water Crisis in Southern California. Studying PFAS exposure in Southern CA's drinking water, the Smith Research Group is working to find out how exposure to PFAS can affect public health and the environment.

Does our research spark your interest and seem like a good fit for you? Check out our Prospective Scholars page for current job openings and to learn how to express interest in applying to the Smith Research Group. Follow along with our research and stay up-to-date with our lab's news for any exciting developments, current events, publications, interviews, and grant announcements. 

To learn more about previous research topics explored by the Smith Research Group, please click here 

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