Fractionation and Sequential Extraction of Heavy Metals in the Soil of Scrapyard of Discarded Vehicles

Abstract

Chemical and physical size fractionation of heavy metals were carried out on 20 soil samples from the scrap yard area. Tessier method was used in sequential extraction. Cadmium showed the highest levels among the other elements studied in the exchangeable fraction (about 33%), while other elements showed low levels in this fraction (> or =1%). Lead and manganese were mostly found in the Fe-Mn oxide fraction, zinc and iron were mostly in residual fraction, while copper was mostly found in the organic fraction of the soil. Soil samples were size-fractionated into four sizes: 1000-500, 500-125, 125-53, and less than 53 microm. The highest levels of Fe, Cu, Pb, Mn, and Cd were found in the medium fraction (500-125 mum), while zinc showed its highest levels in the fine fraction (125-53 microm). The order of heavy metal load in the size fractions was found to be medium > fine > coarse > silt for Fe, Mn, Cu, Pb, and Cd, where it was found as fine > medium > coarse > silt for zinc.

Screening and speciation of heavy metal contaminated soil from an automobile spare-parts market

“…The various concentration trends of the heavy metals under study are consistent with previous observations Li and Thornton, 2001;Jaradat et al, 2006). This fraction is especially important because of the high mobility of metals from this fraction to the aqueous phase.…”

“…29.4% Pb, 22.3% Cu and 24.0% Cd are found in this fraction. In a recent work by Jaradat et al (2006), 13% Pb, 44% Cu and 13% Cd were bound to the organic fraction of soils collected around a scrap yard of discarded vehicles. In an earlier work by Levy et al (1992), the complexation of humic acids with some heavy metals followed the sequence: Cu4Pb4Cd.…”

“…Copper has the highest amount in this fraction (25.8%), while lead and cadmium made up 20.7% and 14.0%, respectively. Recently, Jaradat et al (2006) reported the sequestration of 450% Pb, 25% Cu and 440% Cd by the reducible fraction. In an earlier study, Levy (1992) reported the association of lead, cadmium and copper in the reducible fraction.…”

Geochemistry as an aid in archaeological prospection and site interpretation: current issues and research directions

“…Retention and sequestration of trace elements in soils generally depends on their oxidation state, soil pH, the specific surface area, cation exchange capacity and the presence of clay minerals, Fe oxides, carbonates, phosphates, sulphides and OM (De Matos et al, 2001;Jaradat et al, 2006;Kumpiene et al, 2007). According to Msaky and Calvet (1990), two major processes lead to the accumulations of trace metals in soils; selective adsorption by means of surface complex formation and non-selective adsorption of metal ions by diffuse clay layers.…”

Fractionation and mobility of cadmium and lead in soils of Amol area in Iran, using the modified BCR sequential extraction method

“…Mobility and bioavailability of heavy metals in soil is determined by their chemical forms (Jaradat et al, 2006;Umoren and Udousoro, 2009). Sequential extractions, such as the Tessier procedure (Tessier et al, 1979), have been applied to soils contaminated by various sources.…”