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Title: Basis for the ICRP’s updated biokinetic model for carbon inhaled as CO 2

Here, the International Commission on Radiological Protection (ICRP) is updating its biokinetic and dosimetric models for occupational intake of radionuclides (OIR) in a series of reports called the OIR series. This paper describes the basis for the ICRP's updated biokinetic model for inhalation of radiocarbon as carbon dioxide (CO 2) gas. The updated model is based on biokinetic data for carbon isotopes inhaled as carbon dioxide or injected or ingested as bicarbonate $$({{{\rm{HCO}}}_{3}}^{-}).$$ The data from these studies are expected to apply equally to internally deposited (or internally produced) carbon dioxide and bicarbonate based on comparison of excretion rates for the two administered forms and the fact that carbon dioxide and bicarbonate are largely carried in a common form (CO 2–H$${{{\rm{CO}}}_{3}}^{-})$$ in blood. Compared with dose estimates based on current ICRP biokinetic models for inhaled carbon dioxide or ingested carbon, the updated model will result in a somewhat higher dose estimate for 14C inhaled as CO 2 and a much lower dose estimate for 14C ingested as bicarbonate.
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  1. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Publication Date:
Grant/Contract Number:
Accepted Manuscript
Journal Name:
Journal of Radiological Protection
Additional Journal Information:
Journal Volume: 37; Journal Issue: 2; Journal ID: ISSN 0952-4746
IOP Publishing
Research Org:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org:
Country of Publication:
United States
61 RADIATION PROTECTION AND DOSIMETRY; biokinetics; ICRP; carbon dioxide; bicarbonate
OSTI Identifier: