Meet the Researchers

Name: Georg E. Matt, PhD

Position: Co-Director, Professor of Psychology

Email: gmatt@sdsu.edu

Publication: Google Scholar

Bio: Dr. Matt is a Professor of Psychology in the College of Sciences at San Diego State University and a participating member at the University of California, San Diego Moores Cancer Center. Dr. Matt’s research focuses on human exposure to tobacco smoke toxicants in real-world field settings and on strategies to protect people who do not smoke from the exposure to tobacco smoke toxicants from second- and thirdhand smoke. Dr. Matt is the Principal Investigator of the Thirdhand Smoke Dissemination, Outreach, and Resource Center (Thirdhand Smoke Resource Center) that connects thirdhand smoke researchers with California’s diverse communities. The Thirdhand Smoke Resource Center (1) publishes a website to share Thirdhand Smoke information and outcomes from Thirdhand Smoke Research Consortium-supported research with California residents, communities, tobacco groups, and business owners; (2) raises awareness among California residents through social media campaign; (3) shares what we know about Thirdhand Smoke with community groups, health professionals, and relevant tobacco control stakeholder groups through a series of online workshops; and (4) engages community groups, health professionals, and business owners about policies related to Thirdhand Smoke.

Name: Thomas E. Novotny, MD, MPH, DSc (Hon)

Position: Co-Director, Professor Emeritus School of Public Health

Email: tnovotny@sdsu.edu

Publication: Google Scholar

Bio: Dr. Novotny is an Emeritus Professor of Epidemiology and Biostatistics in the Graduate School of Public Health at San Diego State University (SDSU). Previously, he was a Professor of Global Health and Co-Director of the Joint PhD Program in Global Health at SDSU and the University of California, San Diego. He was Deputy Assistant Secretary for Health from 2015-2017 where he was involved in federal programs on tobacco control and public health. He has been a contributor to and editor of several Reports of the US Surgeon General on Tobacco and Health. Dr. Novotny’s research has most recently focused on the environmental impact of tobacco use, and he initiated and guided the production of a WHO Overview on the life cycle of tobacco impacts on the environment. He also founded the Cigarette Butt Pollution Project, a 501c3 charity registered in California that involves several multi-sectoral collaborative partnerships. He has conducted extensive policy research, advocacy, and conceptual work in this area for over a decade. These activities included work with SDSU and UC researchers on the environmental exposures resulting from tobacco product waste. He has conducted successful dissemination activities with the Truth Initiative in Washington, DC, the California Tobacco Control Program, and other tobacco control advocacy groups.

Name: Kai-Chung Cheng, PhD

Position: Co-Director, Professor of Psychology

Email: kcheng2@sdsu.edu

Publication: Google Scholar

Bio: Dr. Kai-Chung Cheng is an Assistant Professor in the School of Public Health at San Diego State University Imperial Valley. He also worked as a Research Engineer at Stanford University and a Research Scientist at the California Department of Public Health, with more than 10 years of experience in measuring and assessing air pollution and human exposure. He led a cohort study that evaluated the effect of an air purifier on indoor PM2.5 levels and asthma severity in children from low-income families in Fresno, California. He assessed the impacts of indoor smoking on involuntary tobacco smoke exposure in 36 Tribal casinos in California. He recently took the lead on a project that evaluated secondhand exposure to marijuana smoke; which systematically examined exposure of people near others who smoke, offering insight into recommended safe distances from cannabis smoking. His expertise also involves technology development. Using indoor positioning, he created a mobile mapping method to track time-varying locations and exposures of occupants inside buildings. He developed a machine learning method to differentiate smoking from other indoor particle emissions, such as cooking and household cleaning.

Name: Nathan G. Dodder, PhD

Position: Research Scientist, School of Public Health

Email: ndodder@sdsu.edu

Publication: Google Scholar

Bio: Dr. Dodder works in the School of Public Health’s Environmental Health Laboratory at San Diego State University. He is an analytical chemist specializing in applications related to environmental and public health, his expertise includes: 1) Analytical method development to quantify contaminants, metabolites, and protein biomarkers by chromatography/mass spectrometry. 2) Non-targeted mass spectrometry to identify unexpected environmental contaminants. 3) Environmental survey design to assess the occurrence and fate of contaminants in abiotic and biotic matrices. 4) Implementation of quality assurance/quality control procedures for chemical analyses. 5) Scientific software development, including tools for mass spectral interpretation and mass spectral libraries, automated quality control validation, and data analysis and visualization. Dr. Dodder is a Co-Investigator of a couple of the CTE Public Health Projects. In these projects, he leads method development for qualitative and quantitative chemical analyses, with responsibility for QA/QC, laboratory maintenance, and training and supervision of laboratory technicians and student lab assistants. Take a virtual tour of Dr. Dodder’s laboratory here.

Name: Elana Elkin, PhD, MPH

Position: Associate Professor of Environmental Health

Email: eelkin@sdsu.edu

Publication: Google Scholar

Bio: Dr. Elkin is an Assistant Professor of Environmental Health at San Diego State University. She is a toxicologist specializing in reproductive and placental toxicology. Her research seeks to understand how exposures to environmental and occupational pollutants during pregnancy contribute to an elevated risk of developing adverse birth outcomes. Dr. Elkin is new to the Thirdhand Smoke Research Consortium and was recently awarded a pilot grant by the Consortium to investigate the toxic effects of third-hand smoke dust on placental cells. She is an avid genealogist in her spare time. 

Name: Joe Gibbons, PhD

Position: Associate Professor of Sociology

Email: jgibbons@sdsu.edu

Publication: Google Scholar

Bio: Dr. Gibbons is an Associate Professor in the Department of Sociology at San Diego State University. He is a demographer with expertise in spatial analysis and neighborhood studies. In addition to a number of research projects about various public health topics, Dr. Gibbons researches environmental waste from tobacco, e-cigarettes, and marijuana products. His other research interests include health disparities and how gentrification impacts public well-being.

Name: Paula E. Stigler Granados, PhD, MSPH

Position: Assistant Professor of Public Health

Email: pstiglergranados@sdsu.edu

Publication: Google Scholar

Bio: Dr. Stigler Granados is an Assistant Professor in the School of Public Health – Environmental Health and Global Health. Her main areas of interest include global health, public health policy, environmental health, tobacco product waste, and neglected tropical diseases. She received her MS degree in Environmental Health Sciences at San Diego State University and her PhD in Global Health in the joint doctoral program with the University of California San Diego and San Diego State University. Some of her interests include Chagas disease, environmental exposure risks for vulnerable populations, socio-economic determinants of health, geospatial analysis of environmental hazards, climate change, and community-based participatory research. She has worked throughout Latin America and the United States with Indigenous and rural populations on a multitude of projects addressing public health. Dr. Stigler Granados has several on-going research projects, including a Centers for Disease Control and Prevention-funded project to raise awareness among healthcare providers in the U.S. about Chagas disease. She is also utilizing the ECHO model of tele-mentoring to provide learning opportunities for physicians regarding Chagas disease. Dr. Stigler Granados leads a Department of Defense Global Health Initiative grant to conduct surveillance of Chagas disease in military communities along the U.S. Mexico border region. She advocates for community-led projects and has a deep commitment to multi-disciplinary collaborations to solve important public health issues.

Name: Christopher R. Harrison, PhD

Position: Associate Professor of Chemistry

Email: charrison@sdsu.edu

Publication: Google Scholar

Bio: Dr. Harrison’s research centers on the application of chromatographic techniques, principally capillary electrophoresis, for bioanalysis. This ranges from developing coatings and approaches for the separation of proteins and small molecules, to the application of capillary electrophoresis in detecting blood doping agents in athletes. Dr. Harrison is a co-Investigator of a MERG project measuring and reducing exposure to thirdhand smoke. His role in the project is to develop and test a simple, field-deployable, device capable of performing semi-quantitative analysis of thirdhand smoke residue. The aim is to provide the public with a tool that can be used by anyone (like a pool chlorination test kit) to get an approximation of the amount of thirdhand smoke residue present in their living spaces.

Name: Eunha Hoh, PhD

Position: Professor of Environmental Health

Email: ehoh@sdsu.edu

Publication: Google Scholar

Bio: Dr. Hoh is a Professor of Environmental Health in the School of Public Health at San Diego State University. Her previous research interests focused on the fate and behaviors of persistent organic contaminants in the environment and their impact on human health. Her current research projects focus on the ocean and human health, looking at exposure to thirdhand smoke residue, microplastic pollution, tobacco product waste, and wastewater treatment. Dr. Hoh is the Co-Principal Investigator of a few tobacco projects funded by the Tobacco-Related Disease Research Program, including the Thirdhand Smoke Resource Center. She has developed novel analytical methods, including fast and efficient analyses of multiple classes of targeted chemical residues and a nontargeted analytical approach for organic contaminants in various types of environmental and biological samples. She leads chemical analyses required for identifying chemicals of concern in thirdhand smoke and evaluating the removal of them. She also contributes her expertise to analyses of environmental samples and the design and interpretation of all lab analyses. Take a virtual tour of Dr. Hoh’s laboratory here.

Name: Melbourne F. Hovell, PhD, MPH

Position: Professor Emeritus School of Public Health

Publication: Google Scholar

Bio: Dr. Hovell’s research focused on the etiology of health-related behavior following the Behavioral Ecological Model, including studies of classic risk practices, such as diet and physical activity, as well as studies of clinicians’ service delivery. His research also addressed how the influence of and change in culture can be achieved to establish healthy practices in whole populations. His work in secondhand smoke exposure reduction for children led him, along with Dr. Georg Matt, to “discover” thirdhand smoke when he explored nicotine in homes as an explanation of variance in secondhand smoke exposure. He was a Co-Investigator of the Thirdhand Smoke Resource Center. In this role, he contributed to the translation of thirdhand smoke research findings to real-world settings to disseminate findings and improve public health.

Dr. Hovell passed away in 2025. He will be missed by all at the Center.

Name: Scott Kelley, PhD

Position: Professor of Biology

Email: skelley@sdsu.edu

Publication: Google Scholar

Bio: Dr. Kelley is a Professor of Biology at San Diego State University, where he has worked since 2002. His lab combines phylogenetic methods and culture-independent molecular tools to study environmental microbiology. Dr. Kelley has published extensively on the human microbiome, the microbiome of the built environment, and the microbial diversity of many natural environments and species, including volcanic steam vents, corals, and elephants. He has also published dozens of papers on bioinformatics, developed some widely-used tools for analyzing microbial communities using next-generation sequencing, and authored Computational Biology: A Hypertextbook, an introductory textbook on Bioinformatics. Dr. Kelley was a Co-Investigator on the Effects of Thirdhand Smoke Exposure on the Microbiome of Young Children project. In this project, he led the molecular and bioinformatics analysis of human and built environment microbial communities.

Name: Neil Klepeis, PhD

Position: Professor of Environmental Health

Email: nklepeis@sdsu.edu

Publication: Google Scholar

Bio: Dr. Klepeis is an Adjunct Associate Professor in the School of Public Health at San Diego State University.  He works in the fields of Environmental Health and Exposure Science developing digital solutions for exposure education and the promotion of exposure-mitigating policies. Dr. Klepeis is currently working on several research projects that seek to engage tribes, youth, and other priority populations in Citizen Science and Environmental Health Literacy related to second- and thirdhand smoke. These include a project to support California tribes in learning about exposure, a serious game for middle-school curricula that meets Next Generation Science Standards, and a personal exposure monitoring toolkit that includes a custom mobile app and a real-time air quality sensor. Dr. Klepeis studies exposure in many settings, including multiunit housing, outdoors, and casinos.

Name: Kangoh Lee, PhD

Position: Professor of Economics

Email: klee@sdsu.edu

Publication: Google Scholar

Bio: Dr. Lee is a Professor of Economics at San Diego State University. His research focuses on applied microeconomics, including public/urban economics, labor economics, environmental economics, and risk and uncertainty.

Name: Nicolas I. Lopez-Galvez, PhD

Position: Co-Director, Professor of Psychology

Email: nilopez@sdsu.edu

Publication: Google Scholar

Bio: Dr. Lopez-Galvez is an Assistant Professor in Environmental Health in the School of Public Health at San Diego State University (SDSU). He has over a decade of experience evaluating environmental exposures to carcinogens such as pesticides and tobacco-related pollutants among underserved populations, including low-wage immigrant workers, farm workers, children, and those who live near the U.S.-Mexico border region. He utilizes innovative and non-invasive exposure assessment tools in field studies to monitor carcinogens in occupational and community-based settings to better understand their effects on human health. His experience as a first-generation Latino immigrant in the U.S. has influenced his commitment to addressing environmental justice issues and health disparities in minority populations. He received his Bachelor’s degree in Biology from the University of California, Los Angeles (UCLA), followed by a Master’s in Public Health in Environmental Health and a Master of Arts in Latin American Studies at SDSU. He completed his PhD from the University of Arizona with a focus in Environmental and Occupational Health.

Name: Leonardo Nogueira, PhD

Position: Assistant Professor of Exercise & Nutritional Sciences

Email: lnogueira@sdsu.edu

Publication: Google Scholar

Bio: Dr. Nogueira is an Assistant Professor at the School of Exercise and Nutritional Sciences, College of Health and Human Services, San Diego State University. Dr. Nogueira’s research is focused on how chronic inflammatory diseases, environmental pollutants (such as tobacco smoke), and acute and chronic hypoxia interfere with locomotor and respiratory muscle physiology and repair. Dr. Nogueira uses several approaches — in vivo, in situ and ex vivo — to investigate muscle contractile function, fatigue resistance, and exercise-induced muscle regeneration in several different animal models.

Name: Penelope J.E. Quintana, PhD, MPH

Position: Professor of Environmental Health

Email: jquintan@sdsu.edu

Publication: Google Scholar

Bio: Dr. Quintana is a Professor of Environmental Health in the School of Public Health at San Diego State University. She has a research focus on environmental justice concerning exposure to children and vulnerable populations at the US-Mexico border. She studies children’s exposure to toxicants in house dust and on surfaces, such as residual tobacco toxicants remaining after smoking has taken place, known as thirdhand smoke. She applies emerging technologies to assess environmental health problems, such as silicone wristbands for measuring carcinogen exposures in children from thirdhand smoke, and low-cost air sensors deployed in Tijuana at sensitive receptor sites. She studies air pollution arising from the long northbound wait times and lines of idling vehicles at US-Mexico Ports of Entry, exposing border crossers and surrounding communities to traffic pollutants. She is a Scientific Guidance Panel member for the California Environmental Contaminant Biomonitoring Program.

Name: Yu Ni, PhD

Position: Professor of Environmental Health

Email: yni5@sdsu.edu

Publication: Google Scholar

Bio: Dr. Ni is an Assistant Professor in the Division of Epidemiology and Biostatistics in the School of Public Health at San Diego State University. She is an environmental epidemiologist who has dedicated herself to understanding how key environmental exposures impact population health. She has a strong commitment in her work to 1) quantifying the impacts of air pollution exposures on varied maternal and child health outcomes, including pregnancy outcomes, child cardiometabolic health, and neurodevelopment; 2) adopting an integrated approach to studying the interplay and totality of endocrine disrupting chemicals on child development; and 3) determining interactive effects of individual features, such as socioeconomic status and health behaviors, with environmental exposures, seeking to identify vulnerable subgroups.