The GEMS Board of Directors has 13 members, including a president, president-elect, secretary, treasurer, and 9 councilors. The Board meets monthly to plan and prepare for the two annual GEMS meetings.


Holly Mortensen, M.Sc., Ph.D., received her BS from the University of California, Davis, her M.Sc. from Stanford University, and her Ph.D. in Human Genetics from the University of Maryland, College Park. Dr. Mortensen completed her postdoctoral work at the EPA’s National Center for Computational Toxicology, where her projects included defining toxicity related pathways for all annotated human genes, using chemical and disease association and drug target information, data implemented in assay prioritization efforts for the EPA’s ToxCast program. Dr. Mortensen is currently a Bioinformaticist with the Genomic and Bioinformatics Research Core at EPA’s National Health and Environmental Effects Research Laboratory (NHEERL).  Dr. Mortensen is working to establish a computational framework and related database for the analysis of taxonomic applicability of adverse outcome pathways of interest to the US EPA. 


Carol Swartz, DVM, Ph.D, is the Director of In Vitro Toxicology and Formulations Manager at Integrated Laboratory Systems, Inc. in Research Triangle Park, NC. She received her BS in Biochemistry and her DVM from Oklahoma State University, and her PhD in Toxicology from Texas A&M University. Dr. Swartz has over 30 years of experience performing laboratory research in genetic toxicology, molecular biology, and biochemistry and over 20 years of experience with in vitro cell culture and cell-based assays and with bacterial mutagenicity assays and molecular genetic toxicology. Dr. Swartz completed a postdoctoral position at the US EPA with Dr. David DeMarini, where she assessed the mutagenicity of drinking water contaminants (disinfection byproducts and nanoparticles) and sulfur-containing contaminants found in combustion emissions using the bacterial mutagenicity assay, Salmonella whole-genome microarrays, and the mouse tandem repeat germline mutation assays. She was also a post-doctoral trainee at NIEHS, where she studied the biology of uterine leiomyoma with Dr. Darlene Dixon. Dr. Swartz has been with ILS for almost 10 years where she is responsible for conduct of in vitro genetic toxicology studies and all formulation laboratory activities. She is a member of the American Veterinary Medical Association and the Environmental Mutagenesis and Genomics Society, where she is a newly-elected EMGS councilor. She has twice served as Councilor on the Board of Directors for GEMS and has been the GEMS Corporate Sponsorship Coordinator for the past six years.


Nisha S. Sipes, Ph.D., is a Health Science Evaluator in the Biomolecular Screening Branch of the Division of the National Toxicology Program (NTP)/NIEHS. She researches ways to make toxicity testing more efficient and informative using the NTP Tox21 High Throughput Screening data, publicly available data, in vitro to in vivo extrapolation techniques, and computational methods. Before joining the NTP in 2014, Dr. Sipes performed similar analyses toward developmental toxicity as a postdoctoral fellow with the National Center for Computational Toxicology within the U.S. EPA. She obtained her Ph.D. from the Department of Cell and Cancer Biology, as well as an M.S. in Biomedical Engineering from the University of Cincinnati. Dr. Sipes has been recognized with several awards at national and international meetings, including Best Postdoctoral Publication Award from SOT and the Maire W. Taubeneck Award from the Teratology Society (2012). With regard to leadership roles, Dr. Sipes serves on the Membership Committee (2014-present) and Communications Working Group (2016-present) for the Teratology Society, on the Editorial Board for Frontiers in Predictive Toxicology (2012-present) and Reproductive Toxicology (2015-present), and is the NTP lead on the Tox21 Informatics Workgroup (2014-present). In addition, she was the Vice-President for the Network and Leadership Training Organization (2011-2013), Program Committee Member for Teratology Society (2010-2013), and has Chaired and Co-Chaired several symposia for the Society of Toxicology and the Teratology Society (2011-2016). Dr. Sipes has attended a number of Genetics and Environmental Mutagenesis Society meetings and is looking to become an active member in this local Society.


Lisa Smeester, M.S., is a Research Specialist in the Department of Environmental Sciences and Engineering in UNC's Gillings School of Global Public Health, where she is actively involved in UNC's Superfund Research Program as well as several collaborations with the UNC Department of Obstetrics & Gynecology, Division of Maternal-Fetal Medicine. ​Her research interests include using systems biology and toxicogenomic approaches to investigate epigenetic mechanisms of metal-induced disease, with a focus on prenatal and early life exposures. Prior to joining UNC, she spent several years studying AlkB-mediated direct repair of DNA alkylation damage at MIT’s Center for Environmental Health Sciences. Ms. Smeester received her B.S. from Simmons College in Boston, and her M.S. from the Department of Environmental Sciences and Engineering in Gillings, where she studied the role of arsenic as an immunomodulatory agent in children chronically exposed to arsenic via their drinking water. She has authored numerous peer-reviewed publications and book chapters, and is a member of the Association for Women in Science and a lifetime member of GEMS. In addition to the financial responsibilities of her role as Manager of the Fry Lab, she has extensive experience serving as Treasurer for various university and community based organizations in the greater Boston area.

2018-2020 COUNCILORS

Michelle Angrish, Ph.D., is a Toxicologist at the US Environmental Protection Agency where she is the cardiovascular, metabolic disease, and genetic at risk toxicology expert for the Integrated Science Assessment (ISA) documents that are generated by the agency as mandated by the Clean Air Act in support of the establishment of the National Ambient Air Quality Standards regulating the criteria air pollutants. Michelle also supports work across the agency, including support to the Chemical Safety for Sustainability program where she participates in two international workgroups with the goals of: 1) Accelerating the Pace of Chemical Risk Assessment and 2) advancing the Adverse Outcome Pathway (AOP) concept. Michelle also participates in the National Center for Environmental Assessment (NCEA) New and Alternative Methods Team where she develops innovative approaches to incorporating diverse data streams and novel approaches into the risk assessment process. Michelle received a dual doctorate degree in Genetics and Environmental Toxicology from Michigan State University in 2012. Michelle served as a postdoctoral fellow at Wayne state University from 2012-2013 where she investigated the molecular mechanisms of lipolysis. After taking a year to work as a science writer and care for her new daughter, Michelle moved to RTP and began a post-doctoral fellowship at the US EPA with the National Exposure Research Laboratory where she worked with Dr. Joachim Pleil and Michael Madden developing an in vitro method for evaluating the effects of volatile chemicals. Michelle moved to a federal post-doctoral position with the National Health and Environmental Effects Research Laboratory in 2015 where she worked with Dr. Brian Chorley on a two projects: 1) developing a human AOP-based in vitro model for hepatic steatosis and 2) a method to incorporate epigenetic data into the chemical evaluation process. Michelle was awarded two Pathfinder Innovation Projects by the EPA, one of which she served as the project lead and developed a method, in collaboration with Dr. Stephanie Padilla, to evaluate chemical obesogens in zebrafish. Michelle has 13 peer-reviewed publications that include 7 first author and 8 publications since joining the EPA in 2014. Michelle has worked in a GLP lab, academia, and government. Michelle has a strong collaborative history and integrates team members intra- and across-agencies as a team member to the NCEA Environmental Media Assessment Group Systematic Review Team, with NIEHS/OHAT on a case study using Systematic Literature Mapping (SLiM), and with international collaborators advancing the AOP paradigm. Michelle is a member of scientific organizations that include SOT, EMGS, and GEMS, a proud mother of two, and looks forward to the opportunity to serve and support GEMS!

Natalie Saini, Ph.D., completed her Ph.D in 2014 from Georgia Institute of Technology, where she was working on understanding how intrinsic DNA damage and repair pathways contribute to genome instability in yeast. Dr. Saini is currently a postdoctoral scientist in Dr. Dmitry Gordenin’s lab at the National Institute of Environmental Health Sciences. She is working towards establishing herself as an independent researcher in the near future. Dr. Saini’s overarching research goal is to determine the range of genome-wide mutation loads and to identify the mutation signatures in the cells of healthy individuals to decipher environmental and genetic causes of genome instability. She utilizes simple model organisms like yeast to understand how environmental agents affect DNA stability, and to apply this knowledge to answer key questions regarding the impact of environmental damage on mutagenesis in humans, resulting in important insights into how these factors affect human health. Dr. Saini recently was awarded the Young Scientist Award by EMGS and is looking forward to participating the North Carolina Genetics and Environmental Mutagenesis Society.

Alison Harrill, Ph.D., is a Geneticist at the National Institute for Environmental Health Sciences in the Division of the National Toxicology Program (NTP). Her research interests include investigating the role of genetic sequence variation and population dynamics as it relates to toxicity susceptibility, and development/qualification of novel biofluid-based miRNA biomarkers of organ toxicity. She currently serves as an Associate Editor for Toxicological Sciences, co-Chair of the Health and Environmental Sciences Institute’s (HESI) Application of Genomics to Mechanism-Based Risk Assessment Technical Committee, co-chair of the HESI miRNA Biomarkers Working Group, co-Chair of the Society of Toxicology (SOT) Contemporary Concepts in Toxicology Committee, and past Secretary/Treasurer of the Toxicology Division within the American Society for Pharmacology and Experimental Therapeutics. Dr. Harrill received her Ph.D. in Toxicology from the University of North Carolina at Chapel Hill (2009). Dr. Harrill and her team have received several awards, including the Burroughs Wellcome Award for Innovation in Regulatory Science (2013-2016), the SOT Outstanding Published Paper in Advancing the Science of Risk Assessment Award (2009) and the SOT Best Paper Published in Toxicological Sciences (2016).

2017-2019 COUNCILORS

Catherine (Cathy) Sprankle, M.S., is a Senior Communications Specialist at ILS, an RTP company that provides toxicity testing and related services to NIEHS, EPA, and other government and commercial clients. Cathy's group supports the NTP Interagency Center for the Evaluation of Alternative Toxicological Methods (NICEATM), which develops and evaluates non-animal methods for chemical safety testing. Cathy manages the NICEATM website, writes articles on NICEATM activities for the NIEHS newsletter, and assists the NICEATM group with writing and editing scientific manuscripts, poster presentations, and other documents. Prior to joining ILS, Cathy spent over 20 years working as a lab scientist for a number of RTP-area institutions including NC State University, GlaxoSmithKline, and NIEHS. She was an active member of GEMS in the 1980s and 1990s during her 10 years working for CIIT (later the Hamner Institutes for Health Sciences), and won the Best Poster Presentation award at the Fall 1993 meeting. Her other honors include recognition by the Society for Technical Communication for her work as editor of the ICCVAM Biennial Progress report, which NICEATM produces; the 2011-2012 edition of the report received a Distinguished Technical Communication award, the highest possible award, in the 2013 STC national competition. Cathy earned her bachelor’s degree in biology from the University of Virginia and her master’s degree in technical communication from NC State. Her diverse interests are reflected by her many volunteer activities: highlights include volunteering for over 30 years at Raleigh Little Theatre, during which time she has done just about everything except direct a play; developing an online planning and operations manual for the Sanderson High School’s annual marching band competition; serving on the Citizen Planning Committee for a Raleigh park currently under development; and giving guest lessons on toxicology and genetics to students at York Elementary and Daniels Middle Schools.

Natalia Ryan, Ph.D. (formerly VanDuyn), is a toxicologist in the Human Safety – Regulatory Toxicology group at Bayer CropScience.  Her current role involves the analysis and interpretation of high-throughput screening data (including ToxCast and Tox21) for Bayer active ingredients and participating in efforts to improve and expand internal early toxicology screening methods to refine the product development process.  Dr. Ryan also contributes to industry work groups related to computational toxicology and risk assessment.  Dr. Ryan earned her PhD in Toxicology from Indiana University School of Medicine in 2014 where she studied the molecular mechanisms of methylmercury toxicity in C. elegans under the guidance of Dr. Richard Nass.  To expand her expertise in mechanisms of toxicity, she pursued an ORISE postdoctoral fellowship in the National Health and Environmental Effects Research Laboratory (NHEERL) at the US EPA in Research Triangle Park, NC under the mentorship of Drs. Brian Chorley and Chris Corton.  The main focus of her work was integrating genomics into predictive toxicology and creating gene expression biomarkers for nuclear receptor activation to aid in the development of adverse outcome pathways.  She also participated in the High-throughput Toxicity Testing and Cancer Adverse Outcome Pathway task groups and was involved in the Networking and Leadership Training Organization (NLTO).  She has been a member of the Society of Toxicology for eight years and the Molecular and Systems Biology, In Vitro and Alternative Methods and Carcinogenesis Specialty Sections, earning several awards for her research.  Dr. Ryan joined GEMS in 2014 and was the recipient of the Best Talk Award at the 2014 annual fall meeting.  

2016-2018 COUNCILORS

Jenna Currier, Ph.D., is a toxicologist with eight years of multi-disciplinary research experience encompassing analytical chemistry, epidemiology, genomics, bioinformatics, risk assessment, and computational model development. Dr. Currier completed her Ph.D. in 2013 from the University of North Carolina at Chapel Hill under the direction of Dr. Miroslav Styblo. Her research projects focused on the assessment of susceptibility to chronic arsenic toxicity through the optimization of an analytical technique for quantifying toxic trivalent arsenic species in complex biological samples. This work included international collaborations and NIH-funded cohort studies, resulting in four first-authored and eight co-authored peer-reviewed publications. Dr. Currier is a current postdoctoral fellow at the U.S. EPA through the Oak Ridge Institute of Science and Education under the mentorship of Drs. Brian Chorley and Rory Conolly. She is investigating the underlying mechanisms that differentiate cellular responses to oxidative exposures in human lung cells for the purpose of biomarker discovery and predictive model development using a systems biology approach. Dr. Currier’s research efforts have been recognized with several awards at local and national meetings including the GEM’s supported Emerging Scientist Award presented at the 2015 annual EMGS meeting. Dr. Currier is also the current President of the Networking and Leadership Training Organization, which provides networking and career development opportunities for trainees at the U.S. EPA in RTP. 

Caren Weinhouse, Ph.D., is currently a Postdoctoral Associate in the Duke Global Health Institute (PI: William Pan), studying population epigenetic responses to environmental mercury exposure in gold mining communities in the Peruvian Amazon. She received her Ph.D. in Environmental Health Sciences (2015; PI: Dana Dolinoy) and her M.P.H. in Occupational and Environmental Epidemiology (2011; PI: Dana Dolinoy) from University of Michigan. In her dissertation, she reported epigenetic alterations linked to increased risk for liver cancer in isogenic adult mice exposed perinatally to bisphenol A.  She is interested in translating mechanistic toxicology and epigenetics research in animals to global environmental epidemiology settings, with the goal of protecting vulnerable populations in developing countries from unregulated exposures to environmental toxicants. She an active member of the Society of Toxicology and the Environmental Mutagenesis and Genomics Society.

Nagu Keshava, Ph.D, is currently a Senior Toxicologist at National Center for Environmental Assessment, Office of Research and Development (ORD), Environmental Protection Agency (EPA), Washington DC, USA. Prior to moving to EPA, she was at the Centers for Disease Control – National Institute for Occupational Safety and Health (CDC/NIOSH). She graduated with a Ph.D. from West Virginia University majoring in Genetics and Developmental Biology. Her areas of scientific expertise and interests include genetic toxicology, mode of action, risk assessment and cancer biology. At EPA, she has led or contributed to risk assessments and provided scientific support to program offices within EPA and other federal agencies. She was the President of Genetics and Environmental Mutagenesis Society (2011-2012) and organized both fall and spring meetings. She is also a lifetime member of the society. In addition, she is a member of other professional societies including the Environmental Mutagenesis and Genomics Society and the Society of toxicology.  Dr. Keshava has received numerous awards both within and outside of EPA for her scientific contributions. She has authored or co-authored over 40 peer-reviewed articles and book chapters in journals including Cancer Research and Proceedings of National Academy of Sciences. She has also contributed to numerous governmental and intergovernmental reports. Dr. Keshava has served on several committees, organized and chaired workshops and symposium at the Environmental Mutagenesis and Genomics Society and other organizations. 


Tom Hughes, M.S.,  was the co-founder of GEMS in 1983.  He served as the GEMS President three times and has been on the BOD as Councilor, Treasurer, Corporate Sponsor Coordinator and Vice President.  He was awarded the GEMS Lifetime Achievement Award at the Annual Meeting in 2015.  He has been a QA and Records Manager at the US EPA for the past 17 years and a laboratory scientist at the US EPA for five years prior to being a QA and Records Manager.  Scientifically, he was involved in the World Trade Center (WTC) research, where a 20 member Team exposed mice to dusts from the WTC immediately after the 9/11/01 disaster and in the Penobscot River Study in Maine where the water, sediment and drinking water of the Penobscot River and the fish and plants were investigate for toxicity for the Penobscot Indian Nation.  Previous to being at the US EPA, Tom was a Principal Investigator in two contract labs for twenty years, were he conducted GLP testing for industrial clients, and where he conducted toxicology testing for industry, NCI, EPA and NTP.  Tom was the U.S. EPA QA Manager of the Year in 2002 and was a US EPA National Honor Award winner in 2014 for his work with the Penobscot Indians.  He will retireD from the US EPA after 22 years on October 29, 2016 after which he continued to be an invaluable supporter of the mission of GEMS.  

P.O. Box 13475, Research Triangle Park, NC 27709

GEMS is incorporated as a non-profit scientific organization in the state of North Carolina  and with the federal government. 

  • Home
  • Board of Directors
Powered by Wild Apricot Membership Software