title: Doses and risks from the ingestion of Dounreay fuel fragments.
abstract: The radiological implications of ingestion of nuclear fuel fragments present in the marine environment around Dounreay have been reassessed by using the Monte Carlo code MCNP to obtain improved estimates of the doses to target cells in the walls of the lower large intestine resulting from the passage of a fragment. The approach takes account of the reduction in dose due to attenuation within the intestinal wall and self-absorption of radiation in the fuel fragment itself. In addition, dose is calculated on the basis of a realistic estimate of the anatomical volume of the lumen, rather than being based on the average mass of the contents, as in the current ICRP model. Our best estimates of doses from the ingestion of the largest Dounreay particles are at least a factor of 30 lower than those predicted using the current ICRP model. The new ICRP model will address the issues raised here and provide improved estimates of dose.
authors.affiliation: School of Physics and Astronomy, The University of Birmingham, Edgbaston, Birmingham, B15 2TT, UK. p.j.darley@bham.ac.uk
authors.forename: P J
authors.initials: PJ
authors.lastname: Darley
authors.forename: M W
authors.initials: MW
authors.lastname: Charles
authors.forename: T P
authors.initials: TP
authors.lastname: Fell
authors.forename: J D
authors.initials: JD
authors.lastname: Harrison
mesh_terms: D000284:Administration, Oral; D000328:Adult; D001822:Body Burden; D002648:Child; D003106:Colon / Q000378:metabolism*; D003198:Computer Simulation; D005260:Female; D005507:Food Contamination, Radioactive / Q000032:analysis; D006801:Humans; D007223:Infant; D007408:Intestinal Absorption / Q000502:physiology; D008297:Male; D008954:Models, Biological; D010316:Particle Size; D011829:Radiation Dosage; D011848:Radioactive Pollutants / Q000032:analysis / Q000493:pharmacokinetics*; D011850:Radioactive Waste / Q000032:analysis*; D011874:Radiometry / Q000379:methods*; D018570:Risk Assessment / Q000379:methods*; D006113:United Kingdom
chemical_list: D011848:Radioactive Pollutants; D011850:Radioactive Waste