Dr. Walker, Deputy Director of the National Toxicology Program at NIEHS, has over 15 years experience in environmental molecular toxicology, quantitative dose response modeling and risk analysis, with particular emphasis on understanding the carcinogenicity of mixtures of dioxins and other persistent organic pollutants, and the safety of nanoscale materials.
He received his B.Sc. in Biochemistry in England from the University of Bath in 1987 and his Ph.D. in Biochemistry from the University of Liverpool in 1993. Following postdoctoral training in environmental toxicology at the Johns Hopkins School of Hygiene and Public Health in Baltimore MD, he moved to the NIEHS, where he has been since 1995.