Vertical distribution of ²⁴¹Am in the southern Baltic Sea sediment profiles

The contamination of the Baltic Sea with radioactive substances occurred due to the global fallout of atmospheric nuclear weapon tests and the Chernobyl disaster. The knowledge of ²⁴¹Am in the sediments of the Baltic Sea is limited. Thus, this study aimed to determine ²⁴¹Am in sediment cores collected from the southern Baltic Sea. Time-based distributions were derived from age-depth profiles using the ²¹⁰Pb dating method and further corroborated by ¹³⁷Cs profiles. The activities of ²⁴¹Am were measured by alpha spectrometry after radiochemical purification. The results show divergences in the concentrations of ²⁴¹Am at the local level, varying from 0.017 ± 0.001 Bq·kg^-1 at the Gotland Basin station to 3.19 ± 0.23 Bq·kg^-1 in the Gdańsk Basin. These findings enhance our understanding of the radioactive contamination levels in the Baltic Sea and serve as a crucial reference dataset for future assessments and management strategies to mitigate the environmental impact of radionuclides in the region.