In Memoriam: Warren Keith Sinclair

1924-2014

by John D. Boice, Jr., NCRP President, ICRP Main Commission, UNSCEAR Delegate David A. Schauer, NCRP Executive Director Emeritus, ICRU Executive Secretary

Warren K. Sinclair, PhD, a giant in the field of radiation protection, science, and medicine, passed away on 14 May 2014 at 90 years of age, following a stroke the preceding day.

One of the founding fathers of modern radiation protection, Warren was born 9 March 1924, in Dunedin, New Zealand. He was a 1941 graduate of Otago Boys' High School in Dunedin. During 1942–1943, while a student at the University of Otago, he served in the New Zealand Army and manned an antiaircraft battery near Christchurch Harbor, waiting to fend off the Japanese who never came. His first professional job was for the New Zealand government after earning his BSc in 1944, but he was sent back to Otago University the next year by Ernie Marsden (a colleague of Ernest Rutherford) to study for his master's degree in physics. After graduating with first-class honors (in physics) in 1945, Warren was appointed as the first hospital physicist in New Zealand in his hometown of Dunedin. After working in radiotherapy physics with Dr. Peter Jerram (radiotherapist) he realized additional training was essential and made his way to London in 1947 to obtain it.

In London, Warren studied under Professor William Valentine (Val) Mayneord of the Royal Cancer Hospital, obtaining a PhD in physics at the University of London in 1950. He was the leader of the radioisotope center of the Royal Cancer (later Marsden) Hospital and developed many techniques for radiotherapy with the new radionuclides that had become available from the nuclear reactors in Oak Ridge, Tennessee, and Harwell, United Kingdom. Some are still in use today (e.g., 198Au seeds for interstitial therapy).

In 1954, Warren moved to Houston as head of the Physics Department at M.D. Anderson Hospital. He then turned to enhancing the clinical application of new x-ray and gamma-ray beam therapy techniques that had just been developed. Warren recognized that sound calibration techniques were essential to intercomparisons of clinical effectiveness not only at M.D. Anderson but at all radiotherapy centers. He undertook the first measurement intercomparisons ever and recalibrated the St. Louis and Chicago betatrons to agree with those in New York and Houston. At the same time, he made detailed comparisons of the biological effects of these radiations on yeast cells, mice, rats, and chick embryos and was the first to settle, or at least comprehensively address, the question of relative biological effectiveness. It was Warren's work and his influence at the National Cancer Institute that led to the establishment of the Radiological Physics Centers in Houston and elsewhere and made dosimetry in radiotherapy essentially uniform nationwide and indeed, through the international intercomparisons with the National Bureau of Standards (now the National Institute of Standards and Technology), worldwide. Warren became a U.S. citizen in 1959.

From 1960 to 1983, Warren was senior biophysicist at Argonne National Laboratory, engaged in research involving radiation effects in cultured cells. He also served as director of the Division of Biological and Medical Research from 1970 to 1974 and as associate laboratory director until 1981. Warren was also professor of radiation biology at the University of Chicago and subsequently emeritus professor of the university.

In 1977, Warren was elected the second president of the congressionally chartered National Council on Radiation Protection and Measurements (NCRP). Warren was already a prominent member of the International Commission on Radiological Protection (ICRP), chairing its committee on biological effects for many years; the International Commission on Radiation Units and Measurements (ICRU), where he specialized in neutrons and heavy particles; and the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR), where he chaired the biological program. Warren was the only person to be a member of all three organizations at the same time (1977 to 1985) while also directing the program of NCRP as its president. He performed remarkably in these roles and received a rare public acknowledgement by UNSCEAR in 2000 on leaving the committee.

Understanding the needs of radiation protection, the induction of cancer at low doses, and the importance of the study of the Japanese atomic-bomb survivors for risk estimation, Warren altered the focus of the NCRP to enhance the scientific basis of radiation protection. Warren ensured that the NCRP annual meeting became a major event in the field of radiation protection and the proceedings are published each year in the scientific literature. Warren established the Lauriston S. Taylor Lecture in honor of the NCRP founder. Starting in 2004, the Warren K. Sinclair Keynote Address became a significant part of NCRP's annual meeting and remains a lasting recognition of his legacy. This lectureship was made possible by a generous financial gift from Warren to NCRP—a gift that keeps on giving!

Warren was greatly sought after to serve on advisory bodies within the United States, such as those affiliated with the U.S. Department of Energy, the National Institutes of Health, the Environmental Protection Agency, the U.S. Department of Veterans Affairs, and the National Aeronautics and Space Administration. In 1982, Warren was asked by the European Community to chair the first program review of its Life Sciences Program. He was a consultant to the World Health Organization and served on the National Academy of Sciences as chairman of its Board of Radiation Effects Research.

Although Warren "retired" from NCRP in 1991, he continued to frequent the NCRP offices in Bethesda, producing a number of seminal reports until 1999 when a heart operation to repair a defective mitral valve caused him to move to the better climes of southern California to be closer to his family.

Warren published over 200 scientific papers and contributed in a major way to many (another 100 or so) books and reports of national and international organizations. In retirement in California he continued to be consulted by staff members of NCRP and committees of ICRP. In 2010, Warren's extensive collection of reports, publications, and historical documents related to radiation protection and measurements were donated to Colorado State University.

In addition to his leadership roles in NCRP, ICRP, and ICRU, Warren was a past president of the Radiation Research Society (RRS) and of the American Association of Physicists in Medicine (AAPM), which he helped found. Internationally he was an emeritus member of ICRP and a member of the World Health Organization Expert Advisory Panel on Radiation and the Board of the Radiation Effects Research Foundation, Japan. He delivered a number of important named lectures, including the Failla Lecture of RSS in 1987, the H.M. Parker Lecture of the Battelle Foundation in 1992, and the L.S. Taylor Lecture of NCRP in 1993. He received the Coolidge Award of the AAPM in 1986 and was a National Sigma Xi Lecturer from 1992 to 1994.

Warren is survived by his loving wife Elizabeth (Joy); son, Bruce W. Sinclair of Chicago; daughter, Roslyn E. Munn, and son-in-law, Harry A. Munn, of Escondido, California; two grandchildren, Kyle J. Munn of Noblesville, Indiana, and Erin C. Bertelsen of Flagstaff, Arizona; and four great grandchildren.

The complete official NCRP obituary for Warren can be found on the NCRP website.