Sr-90 in fish from the southern Baltic Sea, coastal lagoons and freshwater lake

摘要

Activity concentrations of radioactive Sr-90 were studied in four fish species: herring, flounder, sprat and cod caught in the southern Baltic Sea in two periods: 2005-2009 and 2013-2014. The study included also perch from the coastal lagoons - Vistula Lagoon and Szczcin Lagoon and a freshwater lake - Zarnowieckie Lake as well as additional lake species: pike and bream. Sr-90 activity concentrations were compared in relation to species and to particular tissue: muscle, whole fish (eviscerated) and bones. In 2014, in the Baltic, the maximal 90Sr concentrations were found in fishbones: herring - 039 Bq kg(-1) w.w., cod - 0.48 Bq kg(-1) w.w., and flounder - 0.54 Bq kg(-1) w.w. In the whole fish the maximal concentrations were found in flounder - 0.16 Bq kg(-1) w.w. and cod - 0.15 Bq kg(-1) w.w., while in herring 0.022 Bq kg(-1) w.w. and sprat - 0.026 Bq kg(-1) w.w. they stayed at lower level. Relatively high Sr-90 concentrations were detected in whole fish from freshwater Lake Zarnowieckie: perch - 0.054 Bq kg(-1) w.w., pike - 0.062 Bq kg(-1) w.w. and bream - 0.140 Bq kg(-1) w.w. Concentration ratio (CR) determined for particular fish tissues and for whole eviscerated fish in relation to Sr-90 concentrations in seawater and lake water were showing significant variability unlike the corresponding Cs-137 concentration ratios which are stable and specific for fish species. The study corroborates with the conviction of the growing role of Sr-90 in the overall radioactivity in the southern Baltic Sea as compared to Cs-137. (C) 2016 Elsevier Ltd. All rights reserved.