Exploring methods to prioritise concentration ratios when estimating weighted absorbed dose rates to terrestrial Reference Animals and Plants

Howard, B.J. ORCID: https://orcid.org/0000-0002-9698-9524; Wells, C.; Beresford, N.A.; Copplestone, D.. 2013 Exploring methods to prioritise concentration ratios when estimating weighted absorbed dose rates to terrestrial Reference Animals and Plants. Journal of Environmental Radioactivity, 126. 326-337. 10.1016/j.jenvrad.2013.05.005

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Official URL: http://dx.doi.org/10.1016/j.jenvrad.2013.05.005

Abstract/Summary

The ICRP and IAEA have recently reported Concentration Ratio values (CRwo-media e equilibrium radionuclide activity concentration in whole organism divided by that in media) for Reference Animals and Plants (RAPs) and a wide range of organism groups, respectively, based on a common online database. Given the large number of data gaps in both publications, there is a need to develop methods for identifying the relative importance of improving currently available CRwo-media values. A simple, transparent approach involving the derivation and comparison of predicted internal and external weighted absorbed dose rates for radionuclides considered by ICRP (2009) for terrestrial RAPs is presented. Using the approach of applying a reference value of CRwo-soil ¼ 1 or using the maximum reported values where CRwo-soil >1, we provisionally identify terrestrial radionuclide RAP combinations which could be considered low priority, notably: Ca, Cr and Ni consistently; Mn for all RAPs except Deer and Pine Tree; and Tc for all RAPs but Wild Grass. Equally, we can systematically identify high priority elements and radioisotopes, which largely, but not exclusively, consist of alpha-emitters (especially isotopes of Ra and Th, but also consistently Am, Cf, Cm, Np, Pa, Po, Pu, U). The analysis highlights the importance of the radiation weighting factor default assumption of 10 for alpha-emitters in the ERICA Tool when comparing the magnitude of the internal dose and trying to identify high priority RAP-isotope combinations. If the unweighted Dose Conversion Coefficient (DCC) values are considered, those for alphaemitters are often one order of magnitude higher than those due to some beta-gamma emitters for terrestrial RAPs, whereas with the radiation weighting factor applied they are two orders of magnitude higher.

Item Type:	Publication - Article
Digital Object Identifier (DOI):	10.1016/j.jenvrad.2013.05.005
Programmes:	CEH Topics & Objectives 2009 - 2012 > Biogeochemistry > BGC Topic 3 - Managing Threats to Environment and Health > BGC - 3.2 - Provide the evidence base for setting Environment Quality Standards ...
UKCEH and CEH Sections/Science Areas:	Shore
ISSN:	0265-931X
Additional Keywords:	radioecology, wildlife, data gaps, radionuclides, environmental radioactivity, concentration ratios, reference animals and plants
NORA Subject Terms:	Ecology and Environment
Date made live:	30 Jul 2013 14:55 +0 (UTC)
URI:	https://nora.nerc.ac.uk/id/eprint/502796

Item Type:

Publication - Article

Digital Object Identifier (DOI):

10.1016/j.jenvrad.2013.05.005

Programmes:

CEH Topics & Objectives 2009 - 2012 > Biogeochemistry > BGC Topic 3 - Managing Threats to Environment and Health > BGC - 3.2 - Provide the evidence base for setting Environment Quality Standards ...

UKCEH and CEH Sections/Science Areas:

Shore

ISSN:

0265-931X

Additional Keywords:

radioecology, wildlife, data gaps, radionuclides, environmental radioactivity, concentration ratios, reference animals and plants