Geochemical Background Values for the Characterization of Sediment Contamination with Trace Elements in Romania: A Case Study in the Lower Danube Basin
Source abstract
Abstract
The contamination of the Lower Danube Basin with trace elements has been the subject of intense study in recent years, with several pollution indices being employed for the assessment of water, soil, and sediment quality. Most pollution indices are calculated by comparing the measured concentration to a reference value, with different values from various sources being used. In this study, the threshold values for trace elements (As, Cd, Cu, Hg, Ni, Pb, and Zn) in Romania were selected based on the median of their concentration in stream sediment from 167 locations, which were carefully selected to be far from contamination sources. The threshold values were established based on a calculation starting from the geochemical concentration presented in the Geochemical Atlas of Romania (scale: 1:3,000,000, developed in 2006 by a collaborative Romanian-German team). By using these thresholds, pollution indices were calculated for nine sampling locations, from which suspended sediment, bottom sediment, and active floodplain sediment samples were collected and analyzed in an accredited laboratory. Most of the selected thresholds were found to be below the limits for sediments established by Romanian legislation, except for Cr and Ni, the higher values of which are consistent with the specific geological background of the country and the broader Balkan region.
Source: crossref · Quality: baseline
Research context
OpenAlex topics: Geochemistry and Geologic Mapping · Heavy metals in environment · Radioactivity and Radon Measurements
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
Affiliations
Geological Institute of Romania, 1 Caransebeș St., 012271 Bucharest, Romania
Funding
Ministry of Research, Innovation and Digitization of Romania through “Program Nucleu” · Interreg Danube Transnational Programme SIMONA
References (100+)
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