Dr Lipscomb is a Senior Toxicologist and risk assessor for CTEH, LLC in North Little Rock, AR. He began his career as a biologist at the National Center for Toxicological Research in Jefferson, Arkansas. He later served as a Captain (research toxicologist) in the U.S. Air Force, where he earned the Air Force Achievement Medal for his pioneering work on the military’s first large-scale investigation of human metabolic variability. His Metabolism Section studied the metabolism and distribution of trichloroethylene to support the US EPA’s TCE risk assessment. He completed his federal career as a toxicologist and risk assessor in EPA’s National Center for Environmental Assessment and National Homeland Security Research Center in Ohio, where he was a chemical manager for three different risk assessment programs and led the development of EPA guidance for quantitative risk assessment and emergency exposure guidance values. He received numerous EPA awards and recognition including Bronze Medals for mixtures and cumulative risk, drinking water risk assessment, chemical metabolism, and a Gold Medal for his contributions to the EPA’s IRIS risk assessment for TCE. He has over 100 peer-reviewed publications, book chapters and government technical reports. His interests include quantitative risk assessments of single chemicals and chemical mixtures, in vitro to in vivo extrapolation, toxicokinetics and non-default extrapolations of dosimetry among and between species. Dr Lipscomb is a Diplomate of the American Board of Toxicology and Fellow of the Academy of Toxicological Sciences. He serves on the Health Advisory Board for NSF International and American Industrial Hygiene Association’s Emergency Response Planning Committee. He is past president of the Society for Risk Analysis’s Ohio chapter and Dose Response Specialty Group, the Society of Toxicology’s Risk Assessment Specialty Section and Ohio Valley regional chapter, as well as the American Board of Toxicology. He serves on the Editorial Board for Toxicological Sciences and Toxicology Reports and is an Associate Editor for Toxicology Mechanisms and Methods. He holds bachelor’s and master’s degrees in biology from the University of Central Arkansas and a Ph.D. in interdisciplinary toxicology from the University of Arkansas for Medical Sciences and is an adjunct professor of Toxicology and course director for Human Health Risk Assessment in the Department of Pharmacology and Toxicology at the University of Louisville.