title: Dose assessment for ingestion of a 330 kilobecquerel 60Co hot particle.
abstract: On leaving the irradiated fuel bay at Pickering A nuclear power station, a worker triggered a whole body monitor alarm with activity in or on his head, and despite careful decontamination techniques he subsequently swallowed a hot particle. Over the next 3 d, the radioactivity was tracked through the body. It was then excreted in a single faecal sample and recovered for physical and radiochemical analysis. This analysis demonstrated that the particle contained 330 kBq of 60Co and only traces of other radioactivity. Its dimensions were approximately 50-130 microm and its composition was consistent with that of Stellite 6. A dose assessment was carried out taking into account the residence time of the particle in the mouth and its transit through the body. The estimated committed effective dose was 1.4 mSv, and the equivalent dose to the maximally exposed 1 cm2 of skin, 81 mSv.
authors.affiliation: Health Physics Department, Ontario Power Generation, Whitby, Ontario, Canada L1 N 9E3. david.whillans@opg.com
authors.forename: D W
authors.initials: DW
authors.lastname: Whillans
authors.forename: W J
authors.initials: WJ
authors.lastname: Chase
authors.forename: W H
authors.initials: WH
authors.lastname: Wolodarsky
mesh_terms: D001822:Body Burden; D002170:Canada; D003037:Cobalt Radioisotopes / Q000032:analysis* / Q000737:chemistry / Q000493:pharmacokinetics*; D003198:Computer Simulation; D006801:Humans; D008954:Models, Biological; D009688:Nuclear Reactors; D016273:Occupational Exposure / Q000032:analysis*; D009928:Organ Specificity; D010316:Particle Size; D011829:Radiation Dosage; D011874:Radiometry / Q000379:methods*; D012062:Relative Biological Effectiveness; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014915:Whole-Body Counting
chemical_list: D003037:Cobalt Radioisotopes