Our Team

Our team combines expertise in the four core thematic areas of evidence-based toxicology with deep experience in international research coordination, communication, and science advocacy. 

The team is supported by a Board, ensuring good strategic governance of the Collaboration, and a Scientific Advisory Council supporting the scientific rigour of the Collaborations processes and research outputs (scroll down).

Katya Tsaioun, PhD

Executive Director. Katya is an experienced executive and entrepreneur. Her interests are in driving innovation in academia, industry, regulatory, healthcare and non-profit sectors. She specialises in building multi-sector stakeholder alliances and cross-disciplinary, geographically distributed research advocacy teams.

Sebastian Hoffmann, PhD

Researcher. Sebastian is an in vitro toxicologist and statistician. He has been involved with EBTC since its founding in 2011. He is a long-term, key contributor to defining the philosophy and principles of "evidence-based" toxicology.

Emily Senerth, MPH

Researcher. Emily specialises in evidence synthesis and the integration of evidence into decision-making. Her work is aimed at getting trustworthy data into the hands of policy-makers and helping them to account for all relevant factors when making decisions.

Paul Whaley, PhD

Researcher, Editor. Paul develops guidance aimed at improving the conduct of primary and secondary research, and works on how academic publishing practices can better support a healthy research ecosystem. He is Editor-in-Chief of EBTC's journal, Evidence-Based Toxicology.

Our Board


John “Jack” R. Fowle III PhD, DABT
EBTC Board President

Dr. John R. “Jack” Fowle III is the principal of Science to Inform, LLC, an independent consultant advising clients about the use of science to inform decisions regarding environmental risk and in the development and use of alternatives for animal testing.Prior to 2012 he was the Deputy Director of the U.S. Environmental Protection Agency’s (EPA) Health Effects Division in the Office of Pesticide Programs (OPP) in Washington, DC and was responsible for directing the health risk assessment activities supporting the re-registration of existing pesticides. Dr Fowle managed the integration of new toxicological approaches into OPP’s human health risk assessments. Before OPP, he was Director of EPA’s Neurotoxicology Division, as well as Assistant Laboratory Director, at the National Health and Environmental Effects Research Lab (NHEERL) in Research Triangle Park, NC helping to develop alternatives to animal approaches and to establish the Agency’s computational toxicology program. Dr Fowle has served as Deputy Director of EPA’s Science Advisory Board and as the Science Advisor to U.S. Senator Daniel Patrick Moynihan.Since retiring from EPA Dr Fowle serves on the Board of Directors for the Institute of In Vitro Sciences in Gaithersburg, MD, is President of the Board of Trustees for the Evidence Based Toxicology Consortium and is an AltTox Editor. He is Councilor for the American Society for Cellular and Computational Toxicology as well as President of the Society of Toxicology’s In Vitro and Alternative Methods Specialty section. Dr Fowle received his baccalaureate and doctoral degrees in genetics from George Washington University in Washington, D.C. and he is a board certified toxicologist.

Gerry Kenna, PhD
EBTC Board Vice-President

Dr. Kenna is Pharmaceutical Director of the Safer Medicines Trust, which is an independent UK charity. In this role, he is focused on developing and gaining regulatory acceptance of human biology-based methods that can improve human safety assessment of drugs and other chemicals. In addition, he is an independent Drug Safety Consultant who advises clients in pharmaceutical and biotech companies on how best to select and develop efficacious and safe new drugs, and to validate new predictive safety methods and strategies. Previously, he held scientific leadership roles as a toxicologist in the pharmaceutical and agrochemical industries (at AstraZeneca, Syngenta and Zeneca). These were preceded by academic faculty positions (at Imperial College School of Medicine, London UK; National Institutes of Health, MD USA; King’s College Hospital Medical School, London UK and the National Institute for Medical Research, London UK), in which he led research teams that explored mechanisms underlying human adverse drug reactions. He has authored or co-authored >100 peer reviewed scientific publications, is a member of the International Society for the Study of Xenobiotics and a Fellow of the British Toxicology Society. He received a BSc Hons in Biochemistry from the University of Leeds UK and a PhD in Biochemistry from the University of London UK

Sebastian HoffmannDr Sebastian Hoffmann, PhD. 
Secretary, Research Staff, European Affairs

Sebastian Hoffmann is a specialist in the validation and assessment of in vitro test methods, and the regulation of chemicals (REACH) and cosmetic ingredients. He has been supporting the EBTC secretariat since 2011. Previously, Sebastian has worked for the European Centre for the Validation of Alternative Methods (ECVAM) of the European Commission. His research activities focus on methodological challenges in the assessment of in vitro tests, the design and evaluation of integrated testing strategies, and the application of evidence-based approaches to toxicology. He is an appointed member of the European Commission’s Scientific Committee on Occupational Exposure Limits. Sebastian received his PhD from the University of Konstanz (Germany) in 2005 for his thesis Evidence-based In Vitro Toxicology.

Thomas Hartung, MD, PhD
EBTC Board Treasurer

Dr Hartung is the Director of the Center of Alternatives to Animal testing at Johns Hopkins University. Professor Hartung’s career is focused on the paradigm shift in toxicity testing for improving public health. In his previous role as head of the European Centre for the Validation of Alternative Methods of the European Commission (2002-2008), and his current leadership of the Johns Hopkins Center for Alternatives to Animal Testing (CAAT), he was involved in the implementation of the 2007 NRC vision document Toxicity Testing in the 21st Century: A Vision and a Strategy. Dr Hartung pioneered the concept of evidence-based toxicology and co-founded the EBTC in 2011 to further its implementation. Dr. Hartung has a broad background in clinical and experimental pharmacology and toxicology, and has authored more than 450 publications. His previous work centered on the immune recognition of bacteria, including pyrogen testing and the induced inflammatory responses, as well as the pharmacological modulation of these responses. In addition to being Director of CAAT, Dr Hartung has established a laboratory for developmental neurotoxicity research based on genomics and metabolomics, with the respective technologies made available by a “Thought Leader” award from Agilent Technologies

Emily S Sena, PhD

Dr Sena is a Research Fellow at the Centre for Clinical Brain Sciences, University of Edinburgh, Convener, CAMARADES. She has a background in neuroscience and is a research fellow specialised in the validity of preclinical studies. Her research interests are in the use of systematic review and meta-analysis of preclinical efficacy studies to increase the understanding of critical facets of translational medicine and developing new hypotheses for testing in the laboratory. Since 2015 Dr Sena has led the Collaborative Approach to Meta-Analysis and Review of Animal Data from Experimental Studies (CAMARADES), a multicentre international research collaboration facilitating the pooling and analysis of data from a range of disease models across the basic sciences. To support this she has developed an internationally accessible database, similar to the Cochrane library, to facilitate interpretation of the preclinical data used to justify progression to clinical trial. Dr Sena's research has informed laboratory practice guidelines, editorial policy and the design of clinical trial protocols.

Kristina Thayer, PhD

Since January 2017, Dr Thayer serves as the Integrated Risk Information System (IRIS) Division Director, located within the US Environmental Protection Agency (EPA) National Center for Environmental Assessment (NCEA). IRIS assessments identify the potential for a chemical to cause cancer or non-cancer health effects in people and are considered the top tier source of toxicity information used by EPA and other agencies to inform national standards, clean-up levels at local sites, and set advisory levels. IRIS uses systematic review methods to evaluate epidemiological and toxicological literature and include consideration of relevant mechanistic evidence. Prior to joining EPA, Dr. Thayer was Deputy Division Director of Analysis at the National Toxicology Program (NTP) and Director of the NTP Office of Health Assessment and Translation (OHAT) located on the campus of the National Institute for Environmental Health Sciences (NIEHS). As Deputy Division Director of Analysis, she oversaw OHAT and the NTP Office of the Report on Carcinogens (ORoC). She has also worked in the NTP Office of Liaison, Policy, and Review, the NIEHS Office of Risk Assessment Research, and the NTP Center for the Evaluation or Risks to Human Reproduction (CERHR). Prior to joining the NTP/NIEHS, she was a senior scientist at the World Wildlife Fund and then at the Environmental Working Group. She is considered an expert on the application of systematic review methods to environmental health topics and the use of specialized software and automation approaches to facilitate conducting reviews.

Didier Verloo, PhD

Didier Verloo is working for the European Food Safety Authority (EFSA) since 2005 where he is heading the Assessment and Methodological Support Unit since 2008. This multidisciplinary unit leads and supports the development, implementation and review of evidence based risk assessment and decision support approaches in all fields within EFSA’s remit and was responsible for the EFSA guidance on Systematic Review in food and feed safety risk assessment and the EFSA guidance on Expert Knowledge Elicitations. Recently the unit developed and started to implement an overall framework for Promoting Methods for Evidence Use in Scientific assessments (Prometheus).Didier Verloo graduated as a Veterinarian in 1995 and started his professional career at the Institute of Tropical Medicine in Antwerp on the development of diagnostics, interpretation and medical decision making based on diagnostic test results in human and animal trypanosomosis (sleeping sickness) and worked from 2000-2005 for the Belgian government as an epidemiologist and Risk Assessor. Over those years he built up academic and hands on experience in biostatistics, epidemiology, risk analysis, test validation and provided risk analysis consultancy in public health, construction, finance and engineering.

Daniele Wikoff, PhD

Dr. Daniele Wikoff is the Director of ToxStrategies’ Health Sciences Practice. She specializes in the use of evidence-based methods in support of hazard and risk assessment applications for food ingredients and contaminants, industrial chemicals, and consumer products. She has successfully implemented a turn-key process for conducting systematic assessments at ToxStrategies, with a workflow facilitated by the combination of an experienced multidisciplinary team and use of systematic review software and tools. Dr. Wikoff has diverse experience in applying systematic mapping (scoping reviews) and systematic reviews as platforms for facilitating risk assessment, including development of health-based benchmarks as well as topic-specific application of various organizational concepts for mechanistic data, including key characteristics, adverse outcome pathways, and mode of action. Dr. Wikoff has particular interest in methods development related to the definition and evaluation of data quality, and how elements of internal, construct, and external validity can be used to transparently inform conclusions and provide critical information to decision makers. Dr. Wikoff is involved in a number of global collaborations to advance the practice of evidence-based toxicology, highlighted by her membership on the Board of Trustees and role as the Vice-Chair of the Science Advisory Council for the EBTC, membership on a National Academy of Sciences committee in the capacity of systematic review, co-authorship on the World Health Organization’s systematic review guidance (under development), and service as an Associate Editor for Toxicological Sciences and Regulatory Toxicology and Pharmacology.

Holger Schunemann, Professor, Health Research Methods, Evidence, and Impact

Holger Schünemann is a tenured professor in the Departments of Health Research Methods, Evidence, and Impact and of Medicine at McMaster University. From 2009 to 2019, he completed his two terms as Chair of Clinical Epidemiology and Biostatistics at McMaster University, widely considered the birthplace of evidence-based health care. He had trained in respiratory and exercise physiology and internal and respiratory medicine at the Medical School of Hannover (MD in 1993 & Dr. med. in 1994) and lung biology, epidemiology, internal medicine and preventive medicine/public health at the University at Buffalo (UB), State of New York (M.Sc. Epidemiology in 1997; Ph.D. Epidemiology & Community Medicine in 2000). He was on faculty at UB and, from 2007 to 2009, interim Chair of Epidemiology at the National Cancer Institute in Rome, Italy. Since 2000, he helped to reshape the methodology for guideline development spanning clinical medicine to public health and contributed methodologically and practically to knowledge synthesis research, foremost through his co-leadership of the GRADE working group (www.gradeworkinggroup.org) that he co-chairs. As the author of over 700 peer-reviewed publications (h-index 141/101 google scholar/web of science), he is among the 1000 most cited scientists historically (www.webometrics.info). He has been advisor and chair of many guideline expert groups for WHO, the European Commission, ministries of health, other governmental organizations, and professional societies. He is co-chair of and director of Cochrane Canada and the McMaster GRADE center. Maintaining an active internal medicine practice fulfills his passion for patient care and ensures his research is people-oriented

Martin Stephens, PhD. Founding Director of EBTC

Martin L. Stephens is a senior research associate at the Johns Hopkins Center for Alternatives to Animal Testing (CAAT), where he promotes new methods in toxicology and new approaches to assessing their performance.  Prior to joining Johns Hopkins University in 2011, Dr. Stephens was Vice-President for animal research issues at The Humane Society of the United States. He served on the National Academy of Sciences’ committee that produced the landmark report, Toxicity Testing in the 21st Century: A Vision and a Strategy. Martin has received the Society of Toxicology Enhancement of Animal Welfare Award, the Humane Society of the United States’ Russell and Burch Award, the Doerenkamp-Zbinden Award, and the CAAT Recognition Award for his contributions to alternative methods and animal protection. He received a PhD in biology from The University of Chicago

Our Scientific Advisory Council

  • Daniele Wikoff, PhD
  • Kim Wever, PhD
  • Annette Bitsch, PhD
  • Grace Sembajwe, PhD
  • Gunn Vist, PhD
  • Heather Schaefer, PhD
  • Carlijn Hooijmans, PhD
  • Julie Goodman, PhD
  • Michelle Angrish, PhD
  • Minjun Chen, PhD
  • Rebecca Morgan, PhD
  • Seneca Fitch, PhD
  • Sri Bandhakavi, PhD

Evidence-Based Toxicology Collaboration at
Johns Hopkins Bloomberg School of Public Health
615 N. Wolfe Street, Baltimore, MD 21205

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