Mr. Garner is a research associate at Carlington Community and Health Services, Ottawa. Dr. Krewski is the NSERc/ssHRC/McLaughlin Chair Populat ion Health Risk Assessment at the McLaughlin Centre for Population Health Risk Assessment, Institute of Population Health University of Ottawa Dr. Ashmore is a former head of the National Dose Registry in Radiation Protection Bureau, Health Canada, Ottawa, and affiliate scientist at the McLaughlin Centre for Population Health Risk Assessment, Institute of Population Health, Universi ty of Ottawa Dr. Band is senior medical epidemiologist in Healthy Environments and Consumer Safety Branch, Health Canada, Ottawa, and adjunct cine, University of Ottawa Mrs. Fair is a former chief of Health Statistics Division, Statistics Canada, Ottawa. Dr. Jiang is rese arch associate, McLaughlin Centre for Populati Health Risk Assessment, Institute of Population Health, University of Ottawa. Dr. Letourneau is the former director of the Radiation Protection Bureau, Health Canada, Ottawa. Mr. Semenciw is technical advisor Public Health Agency of Canada, Health Canada, Ottawa. Radiation Dr. Sont is head of the National Dose Registry in Protection Bureau, Health Canada, Ottawa, and affiliate scientist at the McLaughlin Centre for Population Health Risk Assessment, Institute of Population Health, University of Ottawa. Correspondence to: Mr Michael Gamer Carlington Community and Health Services, 900 Merivale Rd., Ottawa, ON Kiz E-mail mgarner The authors have no declared financial interests.