Results of an EC laboratory comparison on ~(40)K, ~(90)Sr and ~(137)Cs in dried bilberry powder

摘要

The evaluation is presented of a laboratory comparison (LC) on ~(90)Sr, ~(40)K and ~(137)Cs in dried bilberries organised in 2011 by the IRMM. The activity concentrations reported by 88 participant laboratories are compared to the reference values of the new reference material IRMM-426 Wild Berries. Nine per cent and 17% of activity concentration results for ~(137)Cs and ~(40)K, respectively, deviate more than 20% from the reference values, a result worse than that obtained in previous LCs. For ~(90)Sr, about 88% of results lie within 30% of the reference value, better than observed in previous LCs. But only 58% of ~(90)Sr results are satisfactory in terms of the E_n criterion, indicating difficulties with a complete uncertainty estimation.