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Evidence-Based Toxicology Collaboration


Katya Tsaioun

Dr Katya Tsaioun, PhD. Director

Dr. Tsaioun is a Director of Evidence-based Toxicology Collaboration at Johns Hopkins Bloomberg School of Public Health, where she leads international multi-stakeholder efforts to establish evidence-based methodologies and practices in translational research to inform regulatory decisions. The focus of Dr. Tsaioun’s career has been on translation of scientific innovations into policies and technologies enabling improvements in public health. She spent almost two decades in pharmaceutical industry leading translational drug-discovery teams, subsequently founding her company, Apredica, which became a leader in commercializing de-risking technologies. After a successful acquisition of Apredica by Cyprotex, PLC (now Evotec), she served as a CSO and Board member in the merged public company. Dr. Tsaioun is serving on advisory boards and review committees of a number of governmental, commercial and non-profit organizations. She earned her Ph.D. in Human Nutrition Science from Tufts University Friedman School of Nutrition Science and Policy and completed post-doctoral training in neurochemistry at Harvard Medical School.

Martin Stephens

Dr Martin Stephens, PhD. Founding Director

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

Sebastian Hoffmann

Dr Sebastian Hoffmann, PhD. 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.

Paul Whaley

Paul Whaley. Research Staff

Paul Whaley is an experienced advocate of the use systematic methods for reviewing evidence to support the development of environmental policy and regulation, working with a range of US and European regulators, industry, NGO and academic organisations to encourage uptake of improved evidence-based methodologies for chemical risk assessment. Paul is Associate Editor for Systematic Reviews at the journal Environment International (2017 IF 7.297), and is based at Lancaster Environment Centre in the UK. Paul is leading EBTC's work on systematic evidence surveillance methods and approaches to automation of systematic reviews, and is co-lead of EBTC's development of new tools for improving the quality and consistency of peer-review of in vitro studies.