[en] Sampling and sample preparation are known to carry large, but typically unknown uncertainty contributions to the final analytical data and there is a lack of qualitative and quantitative data on the comparability of results achieved by different sampling methods. To this end an intercomparison exercise was carried out to compare different methods for the collection of suspended material used for the monitoring of environmental radioactivity in freshwater bodies. This paper presents the results of this intercomparison exercise in which 'in situ' particulate sampling devices were compared in field exercises performed in the Kiev Reservoir (Ukraine) and in the Po River (Italy). The main criterion for this intercomparison was the agreement among the ¹³⁷Cs activity concentrations associated with the suspended particles expressed as Bq x g^-1 and among the (C/N) molar ratios measured on the suspended particles. In addition, an estimate of the uncertainties associated with each measuring method has been performed. (author)

[en] Full text: The evaluation of the pattern of environmental contamination is vitally dependent on reliable data, which derive from complex analytical processes, in which each step of the process, i.e. sampling, sample transportation, treatment, analysis and evaluation and interpretation of the results can affect to some degree the accuracy and precision of the final analytical data. Advances in analytical techniques and improved laboratory practice have reduced many sources of uncertainties which can originate during the laboratory analytical procedures, but the assessment of uncertainties associated with sampling of environmental components has not been fully considered in the past, since collaborative field studies require noteworthy organisational efforts. Sampling and sample preparation/processing are known to carry large, but typically unknown uncertainty contribution to the final analytical data and there is a lack of qualitative and quantitative data on the comparability of results achieved by the different sampling methods. To this end an intercomparison programme was founded by the European Commission, in which Institutions from the European Union and from Ukraine participated using their own in situ methods for collection of suspended material and fixation of dissolved radiocaesium in fresh water bodies. This paper presents the outcome of this study: limits and field applicability of the most widely used sampling methodologies for water and suspended particle in aquatic environments. (author)