Multi-elemental composition of the Sava River sediments (Slovenia,EU)

The Sava River is the longest river in Slovenia and has been subjected to pollution in the past. Fine-grained channel sediments, which were deposited during the high-water event in July 2009, along the river course in Slovenia were sampled at 12 locations in order to determine the content of a large set of chemical elements and assess possible levels of pollution. Sediment samples were air-dried. Two grain size fractions (<0.063 and <0.125 mm) were prepared for chemical analyses by dry sieving. Elemental levels of each sample were determined after aqua regia extraction (1 h, 95 °C) by inductively coupled plasma mass spectrometry. Elemental levels did not exceed the legislation action limit values, indicating that the Sava River recently deposited alluvial sediments are not contaminated with potentially toxic metals. The results show that the chemical composition of the Sava River sediments is comparable to the average composition of stream sediments within Europe. Some light impacts of anthropogenic activities and lithological-driven influential factors to the elemental composition of sediments were observed. Slight As enrichment is possibly a consequence of eroding of slag dumps and As-contaminated soil on Sava River banks and emissions from treated sewage waters. Lead (Pb) is increased in the Litija area as a consequence of historic mining and increased zinc (Zn) and cadmium (Cd) concentrations after the Savinja River confluence because of historic smelting industry in its catchment area. Phosphorous levels in sediments are very likely driven by the emissions from farming and urbanisation. Increased Ba and Pb levels (but still being below the action value) are detected in sample downstream Kr?ko.