Radon-222 dose rates to burrowing mammals

Estimates of absorbed dose rates as a consequence of exposure of wildlife to natural background radionuclides are required to put results of assessments conducted for releases of radionuclides from licensed sites into context. There have been recent review papers in which estimated dose rates to marine, freshwater and terrestrial wildlife (specifically the ICRP Reference Animals and Plants (ICRP 2008)) from 40K and radionuclides in the 238U and 232Th series have been presented (Beresford et al. 2008; Hosseini et al. 2010). Average estimated weighted absorbed dose rates to all organisms considered were in the region of 1 µGy h-1. However, there is to date, only one study published in the refereed literature which estimates dose rates to burrowing mammals as a consequence of inhalation of 222Rn (Macdonald & Laverock 1998). The results of this study suggested that dose rates from 222Rn may be an order of magnitude greater than those received from 40K, and 238U and 232Th series radionuclides. However, the study was conducted in an area of Canada with radon-rich soils and the results may not be typical for most areas.