Director of Science

John D. Boice, Jr.

Telephone: (301) 657-2652



is currently Professor of Medicine at Vanderbilt University School of Medicine, Nashville, Tennessee. He was President of the National Council on Radiation Protection and Measurements (NCRP), Bethesda, Maryland from 2012 to 2018. Dr. Boice is an international authority on radiation effects and served on the Main Commission of the International Commission on Radiological Protection for 20 y and as a U.S. advisor to the United Nations Scientific Committee on the Effects of Atomic Radiation for 25 y. During 27 y of service in the U.S. Public Health Service, Dr. Boice developed and became the first chief of the Radiation Epidemiology Branch at the National Cancer Institute.

Dr. Boice has established programs of research in all major areas of radiation epidemiology, with major projects dealing with populations exposed to medical, occupational, military and environmental radiation. These research efforts have aimed at clarifying cancer and other health risks associated with exposure to ionizing radiation, especially at low-dose levels. Dr. Boice's seminal discoveries and over 500 publications have been used to formulate public-health measures to reduce population exposure to radiation and prevent radiation-associated diseases.

He has delivered the Lauriston S. Taylor Lecture at the NCRP and the Fessinger-Springer Lecture at the University of Texas at El Paso. In 2008, Dr. Boice received the Harvard School of Public Health Alumni Award of Merit. He has also received the E.O. Lawrence Award from the Department of Energy — an honor bestowed on Richard Feynman and Murray Gell-Mann among others — and the Gorgas Medal from the Association of Military Surgeons of the United States. In 1999 he received the outstanding alumnus award from the University of Texas at El Paso (formerly Texas Western College). Dr. Boice directs the Million U.S. Radiation Workers and Veterans Study to examine the lifetime risk of cancer following relatively low-dose exposures received gradually over time.

john d. boice, jr. – BIO

Advisors to the President

Preston_2014 R. Julian Preston

Telephone: (301) 657-2652



is currently a Special Government Employee (Expert) with the Radiation Protection Division of the U.S. Environmental Protection Agency (EPA). He was previously the Associate Director for Health for the National Health and Environmental Effects Research Laboratory of EPA. He also served as Director of the Environmental Carcinogenesis Division at EPA and as senior science adviser at the Chemical Industry Institute of Toxicology. He has been employed at the Biology Division of the Oak Ridge National Laboratory and has served as associate director for the Oak Ridge–University of Tennessee Graduate School for Biomedical Sciences. Dr. Preston's research and current activities have focused on the mechanisms of radiation and chemical carcinogenesis and the approaches for incorporating these types of data into cancer risk assessments.

Dr. Preston currently serves on two NCRP committees and is a member of the National Academy of Sciences Nuclear and Radiation Studies Board and a member of an Office of Science and Technology Policy Committee on Low Dose Radiation Research. Dr. Preston was chair of Committee 1 of the International Commission on Radiological Protection (ICRP), a member of the ICRP Main Commission, and the Representative and a member of the U.S. delegation to the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR). He served as Chair for the National Research Council's Committee to Assess the Scientific Information for the Radiation Exposure Screening and Education Program and on the Task Group on the Biological Effects of Space Radiation. He is an associate editor of Environmental and Molecular Mutagenesis and Chemico-Biological Interactions. Dr. Preston has had more than 200 peer-reviewed papers and chapters published. He received his BA and MA from Peterhouse, Cambridge University, England, in genetics and his PhD from Reading University, England, in radiation genetics.

r. julian preston – BIO
Toohey_D Richard E. Toohey

Telephone: (301) 657-2652



received his PhD in physics from the University of Cincinnati in 1973. He spent the first part of his career at Argonne National Laboratory in both research and operational health physics. He recently retired from Oak Ridge Associated Universities, where he served as director of the Radiation Internal Dose Information Center, as Senior Health Physicist for the Radiation Emergency Assistance Center/Training Site, Director of Dose Reconstruction Programs, and Associate Director of the Independent Environmental Assessment and Verification Program. He is currenly employed by M.H. Chew and Associates.

He is certified in comprehensive practice by the American Board of Health Physics, was the 2008 to 2009 President of the Health Physics Society, is a member and director of NCRP, Treasurer of the International Radiation Protection Association, and Past Chair of the Scientific Advisory Committee for the U.S. Transuranium and Uranium Registries. His specialties are internal radiation dosimetry, dose reconstruction, and radiological emergency response. Dr. Toohey has 125 publications in the open literature, and is a retired Lt. Colonel, U.S. Army Reserve.

richard e. toohey – BIO
Roy E. Shore Roy E. Shore

Telephone: (301) 657-2652


was a Professor and Chief of the Epidemiology Division at New York University School of Medicine before going to the Radiation Effects Research Foundation (RERF) in Hiroshima-Nagasaki as Vice Chairman and Chief of Research. He is an author of ~100 radiation-related publications and is currently working with other RERF investigators on studies of radiation and various diseases.

He has served on numerous governmental and scholarly committees, including as a long-time member of the International Commission on Radiological Protection and NCRP, and has served on various committees or task groups for the United Nations Scientfic Committee on the Effects of Atomic Radiation, the World Health Organization, the National Academy of Sciences, the National Cancer Institute, and the U.S. Environmental Protection Agency, among others. His interests include the effects of radiation on both cancer and noncancer disease incidence, and understanding the epidemiologic and biological modification of radiation effects by various environmental, genetic and age factors.

roy e. shore – BIO

Active Staff Consultants

CohenS Sarah S. Cohen

Telephone: (301) 657-2652

Sarah S. Cohen

CohenSis an epidemiologist and biostatistician with EpidStat Institute and a consultant to the NCRP with over 15 y of experience in the design and conduct of epidemiological studies. Dr. Cohen’s areas of expertise include cancer epidemiology, obesity, pharmacoepidemiology, occupational health, and radiation health effects. She has spent nearly 15 y collaborating on epidemiologic studies of worker health in relation to radiation exposure including cohort assembly and tracing as well as statistical modeling. In addition, Dr. Cohen is currently Adjunct Assistant Research Professor of Medicine in the Division of Epidemiology within the Department of Medicine at the Vanderbilt University School of Medicine.

Sarah S. Cohen – BIO

  • Million Person Study
Gray J Joel E. Gray

Telephone: (301) 657-2652


Gray J

is Professor Emeritus, Mayo Clinic College of Medicine and President of DIQUAD, LLC (Dental Image Quality and Dose), a firm that evaluates dental image quality and dose through the mail. Dr. Gray received his BS in Photographic Science and Instrumentation in 1970, an MS in Optical Sciences in 1974, and a PhD in Radiological Sciences from the Institute of Medical Sciences, University of Toronto in 1977.

He served as a Diagnostic Medical Physicist at Mayo Clinic Rochester for 20 y, helped develop and obtain U.S. Food and Drug Administration (FDA) approval for Lorad's (now Hologic) first digital mammography system, and assisted in the development of the microStar patient dosimetry system using optically stimulated dosimetry material while at Landauer, Inc. After leaving Landauer, Dr. Gray founded DIQUAD and continues to operate that business today.

Dr. Gray published the first two books on quality control in medical imaging in 1976 under contract to FDA while in graduate school. Dr. Gray is the primary author of the first quality control text (Quality Control in Diagnostic Imaging—A Quality Control Cookbook) which is in use worldwide and has been translated into Chinese.

His primary areas of interest include image quality in medical and dental imaging, and optimization of image quality and radiation dose. He serves as a consultant to healthcare organizations and industry. Dr. Gray has served on many national and international advisory committees, including the International Commission Radiological Protection (Committee 3, Radiation Protection in Medicine) and is active in projects with the International Atomic Energy Agency (IAEA) and the World Health Organization. He has co-authored eight publications for the IAEA including educational programs and taught courses for the IAEA in several countries. He has over 170 publications in refereed journals and numerous book chapters, and presented lectures and refresher courses in the United States and overseas. He has visited over 40 countries for both business and pleasure.

Dr. Gray was responsible for starting the first Medical Physics Residency Program at Mayo Clinic in 1990. He has mentored masters and doctoral students, and Medical Physics residents.

He was elected to NCRP in 1986 and has served on numerous committees producing NCRP Report No. 99, Quality Assurance for Diagnostic Imaging; Report No. 147, Structural Shielding Design for Medical Imaging Facilities; and Report No. 160, Ionizing Radiation Exposure of the Population of the United States. He has served as a Technical Consultant for NCRP Commentary No. 20, Radiation Protection and Measurement Issues Related to Cargo Scanning with Accelerator-Produced High-Energy X Rays; NCRP Report No. 172, Reference Levels and Achievable Doses in Medical and Dental Imaging: Recommendations for the United States; and is presently serving on Scientific Committee 4-5 on radiation protection in dentistry supplement, in that capacity. After serving 18 y on the Council he was named a Distinguished Emeritus Member in 2005.

Dr. Gray is a Fellow of the American Association of Physicists in Medicine (AAPM) and the American College of Medical Physics. In 2010 he received the Lifetime Achievement Award from the Upstate New York Association of Medical Physicists and in 2011 the Edith Quimby Lifetime Achievement Award from the AAPM.

joel e. gray – BIO

Michael P. Grissom Michael P. Grissom

Telephone: (301) 657-2652

Michael P. Grissom


MICHAEL P. GRISSOM is a Technical Staff Consultant for NCRP and is the President of MPG-HP, Inc., Riverside, California a private consulting firm. He is a recognized authority on operational health physics issues, particularly related to radiation protection in management, military, reactor, medical, and accelerator operations. During 20 y of service in the U.S. Navy, Mr. Grissom served as a Radiation Safety/Laser Safety Officer (hospital) and provided Radiation Health Officer support to the Naval Radiological Controls Program (propulsion, industrial and weapons).

Mr. Grissom conducted research in biophysics and radiobiological effects at the Armed Forces Radiobiology Research Institute, Bethesda, Maryland as a junior then senior scientist and served as the Director of Medical Records Search for the Navy Nuclear Test Personnel Review, Office of the Chief of Naval Operations, Washington, DC. Mr. Grissom provided support to the Effluent and Dose Assessment Group, Three Mile Island Unit 2 Recovery Team in 1979 to 1980. He has delivered numerous presentations at scientific and professional society meetings. In 2012, Mr. Grissom became a Fellow of the Health Physics Society (HPS).

He previously received the HPS Volunteer Award for services associated with the Medical Health Physics Section and is a Past President of the HPS Accelerator Section. He also served in a number of positions for Stanford University over a period of 16 y at the Stanford Linear Accelerator Center National Accelerator Laboratory, Menlo Park, California including Department Head, Operational Health Physics, and Assistant Associate Director for Environment, Safety and Health.

Michael P. Grissom – BIO

Helen A. Grogan

Telephone: (301) 657-2652


is President of Cascade Scientific, Inc., an environmental consulting firm. Dr. Grogan received her PhD from Imperial College of Science and Technology at the University of London in 1984 and has more than 25 y of experience in radioecology, environmental dose reconstruction, and the assessment of radioactive and nonradioactive hazardous wastes. She first worked at the Paul Scherrer Institute in Switzerland on the performance assessment of radioactive waste disposal for the Swiss National Cooperative for the Disposal of Radioactive Waste (Nagra). Dr. Grogan was actively involved in the early international cooperative efforts to test models designed to quantify the transfer and accumulation of radionuclides and other trace substances in the environment.

Validation of computer models developed to predict the fate and transport of radionuclides in the environment remains a key interest of hers. In 1989 Dr. Grogan returned to the United Kingdom as a senior consultant to Intera Information Technologies before moving to the United States a few years later, where she has worked closely with Risk Assessment Corporation managing the technical aspects of a wide variety of projects that tend to focus on public health risk from environmental exposure to chemicals and radionuclides. Dr. Grogan has served on committees for the National Academy of Sciences, the International Atomic Energy Agency, the U.S. Environment Protection Agency, and NCRP. She co-edited the text book Radiological Risk Assessment and Environmental Analysis published by Oxford University Press in July 2008, and authored the chapter on Model Validation.

helen a. grogan – BIO

Rosenstein Marvin Rosenstein

Telephone: (301) 657-2652



is a consultant, currently concentrating on the preparation of scientific reports produced by NCRP in all subject areas. From 1982 to 1995, he was Director, Office of Health Physics at the Center for Devices and Radiological Health, U.S. Food and Drug Administration. He also served in a number of scientific and management positions related to radiation protection during his 33 y career as a Commissioned Officer in the U.S. Public Health Service, from 1962 to 1995. He received a BS in Chemical Engineering (University of Maryland, 1961), an MS in Environmental Engineering (Rensselaer Polytechnic Institute, 1966) and a PhD in Nuclear Engineering (University of Maryland, 1971). His technical work has concentrated on radiation dosimetry, particularly with regard to x rays used for medical diagnosis, epidemiological studies of exposed populations, and public radiation emergencies.

He is a Distinguished Emeritus Member of NCRP (after serving as a Council member for 18 y), and an Emeritus member of Committee 3 (Protection in Medicine) of the International Commission on Radiological Protection [after serving on Committee 3 for 28 y (1985 to 2013)]. He was also a member of the International Commission on Radiation Units and Measurements report committee that produced Report 74, Patient Dosimetry for X Rays Used in Medical Imaging.

marvin rosenstein – BIO

Smith J James M. Smith

Telephone: (301) 657-2652

James M. Smith

Smith J

is a consulting physicist and an adjunct professor at Emory University’s Rollins School of Public Health. He began his career as a research physicist at the former RCA Space Center in Princeton, New Jersey, and later became associate research professor at the University of Utah School of Medicine. He was founding chief of the Radiation Studies Branch at the U.S. Centers for Disease Control and Prevention (CDC), where he also held a Distinguished Scientist appointment. In 1994 he received the U.S. Public Health Service Superior Service Award for establishing CDC as major international focus for radiation studies.

Dr. Smith has consulted on nuclear threat countermeasures for the International Atomic Energy Agency in Vienna, the White House Office of Science and Technology Policy, and the G-7 Global Health Security Action Group. He traveled extensively advising public health officials and nongovernmental organizations in the aftermath of Chernobyl and Fukushima nuclear crises. Currently, he is staff consultant to NCRP’s Scientific Committee on Emergency Responder Dosimetry. He received his MS in theoretical physics and PhD in experimental physics from West Virginia University and completed his post-doctoral research at Florida State University’s Institute of Molecular Biophysics.

James M. Smith – BIO

Townsend-L Lawrence W. Townsend

Telephone: (301) 657-2652

Lawrence W. Townsend

Townsend-Lis the Chancellor’s Professor Emeritus of Nuclear Engineering, The University of Tennessee, Knoxville. He has a BS in Physics from the U.S. Naval Academy, an MS in Physics (experimental nuclear) from the Naval Postgraduate School, and a PhD in Physics (Theoretical Nuclear) from the University of Idaho. He served for 7 y as a nuclear submarine engineer officer. After a short stint as a Research Assistant Professor of Physics at Old Dominion University, he became a National Aeronautics and Space Administration (NASA) Research Scientist and Senior Research Scientist where his research has focused on nuclear interactions of cosmic rays and their implications for space radiation shielding and crew protection. For these efforts, he was awarded an NASA Scientific Achievement Medal. In 1995 he retired from NASA and entered academia at the University of Tennessee where he retired in June 2017. He is a Fellow of the American Nuclear Society, a Fellow of the Health Physics Society, and an Associate Fellow of the American Institute of Aeronautics and Astronautics. In 1998 he served as the Organizing Committee Chair for the NCRP Annual Meeting and was elected a Member of Council. He was appointed as a Distinguished Emeritus Member of Council in 2010. He has served as a member of Scientific Committee (SC) 75, Chair of SC 1-7, and Consultant to SC 1-24 Phase I.

Lawrence W. Townsend – BIO

Vetter Richard J. Vetter

Telephone: (301) 657-2652



is Professor Emeritus and former Radiation Safety Officer at the Mayo Clinic in Rochester, Minnosota. He received his BS and MS degrees in Biology from South Dakota State University and his PhD in Health Physics from Purdue University. He is board certified by the American Board of Health Physics and the American Board of Medical Physics. He served on the Purdue University faculty from 1970 to 1980 and the Mayo Clinic staff and faculty from 1980 to 2010. Dr. Vetter is a member of the National Academies Nuclear and Radiation Studies Board, the Government Liaison for the Health Physics Society (HPS), and a member of the Executive Council of the International Radiation Protection Association. He is a Fellow of HPS and the American Association of Physicists in Medicine and received the HPS Founders Award.

He is past Editor-in-Chief of Health Physics, past president of HPS, past president of the American Academy of Health Physics, and author or coauthor of more than 220 publications, books, book chapters, and other articles. He served as Vice Chair of the U.S. Nuclear Regulatory Commission Advisory Committee for Medical Uses of Isotopes and member of the Radiation Advisory Committee of the U.S. Environmental Protection Agency Science Advisory Board. He served on the Board of Directors of NCRP, Chair of the NCRP Nominating Committee, and Chair of three and member of two NCRP scientific committees resulting in four NCRP reports and one NCRP statement. Dr. Vetter has received outstanding alumnus awards from South Dakota State University, the Purdue School of Pharmacy and Pharmacal Sciences, the Purdue School of Health Sciences, and the Purdue College of Health and Human Sciences.

richard j. vetter – BIO


Administrative Staff

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Last modified: May 25, 2015