Assessment of Heavy Metal Concentrations with Fractionation Method in Sediments and Waters of the Badovci Lake (Kosovo)

Table 1

Toxic metal fractionation in the sediments based on Tessier et al.’s [11] procedure in the present study.

Fraction	Chemical extractions	Time (h)	Temp. (°C)	Designation
F1	8 ml 1.0 M MgCl2, pH = 7	1	20	Exchangeable
F2	20 ml 1.0 M CH3COONa/CH3COOH, pH = 5	5	20	Bound to carbonates
F3	20 ml 0.04 M NH2OH·HCl/25% HAc solution	5	96 ± 3 with occasional agitation	Reducible (bound to iron and manganese oxides)
F4	5.0 ml 0.02 M HNO3, 5.0 ml H2O2 30%; 6.0 ml H2O2; CH3COONH4/20% (v/v) HNO3	2; 3; 0.5	85; 20	Oxidizable (bound to organic matter)
F5	5 ml HNO3 + 10 ml HF + 10 ml HClO4	Until completely dissolved	Warm	Residual (bound to the soil matrix)

After each extraction stage, the samples were centrifuged and liquid-fraction-decanted, and 10 ml redistilled water was added to the residue 3 times (samples were centrifuged and water was removed) before proceeding to the next extraction.