Pb-Cs dating of an oxbow lake from the Danube delta

The issue of pollution in South Eastern Europe lacustrine environments is highly complex, involving industrial inputs, emerging contaminants (including microplastics and heavy metals), diverse chemical compounds and anthropogenic radioactivity-largely resulting from nuclear bomb testing and the Chernobyl disaster. Several methods for radiodating sediment have been developed and refined over the past decades to reconstruct temporal gradients of pollutant deposition. In this context, our study aims to validate Pb-Cs dating procedures for lacustrine environments, with the objective of advancing the understanding of depositional mechanisms and assessing mitigation processes. This paper presents the radiodating procedure applied to cores from a Danube Delta oxbow lake, highlighting both its strengths and limitations. While 210Pb enables the inference of sedimentation rates, 137Cs provides a chronological marker associated with relatively recent nuclear events. The results reinforce the potential of the method, but also reveal weaknesses elated to sampling operations and the need for further detailed explanations regarding recent changes in sedimentation rates. Overall, the findings are promising and offer a positive outlook for radioecological studies in the region.