A review of Cs-137 transfer to fungi and consequences for modelling environmental transfer

A review of the published literature describing Cs-137 transfer to fungi wa s carried out, summarising the collated data to determine factors controlli ng transfer and identify an appropriate modelling approach to predict futur e contamination. Cs-137 transfer ratios (TR) are derived for fungi species collected within Europe and the CIS. Considerable variability in TRs is dem onstrated, with TRs varying between < 0.001 and > 10 m(2) kg(-1) across all species and over three orders of magnitude for individual species (e.g. Bo letus badius). Generally, meta-information (such as habitat and soil attrib utes) is poorly reported in the literature so that classification of the TR is limited to the effect of nutritional type (P < 0.025) in the order myco rrhizal > saprophytic approximate to parasitic. Analysis of the literature data set (a heterogeneous source) suggests that there is no statistical evi dence to indicate a decrease in TRs for 10 years after the Chernobyl accide nt. Spatial analysis of a data set for Belgium indicates variability in Cs- 137 transfer within a sampling location, such that fruitbodies collected ov er a scale of approximately 5 km would show activities as variable as those collected over a much larger scale ( approximate to or > 50 km). Therefore , it is proposed that the collated data sets for individual species can be used to derive "best estimates" for the parameters describing the distribut ion of TRs. These can then be used to estimate an "effective" TR, which, wh en combined with local soil deposition level and frequency and effect of cu linary practices, can give an estimate of the activity of fungi consumed by the general population. (C) 1999 Elsevier Science Ltd. All rights reserved .