Chemical Partitioning of Cadmium, Copper, Nickel and Zinc in Soils and Sediments Containing High Levels of Heavy Metals

Abstract

Three soils and a sediment which had undergone prior massive additions of heavy metals were sequentially extracted so that Cd, Cu, Ni, and Zn could be partitioned into five operationally defined geochemical fractions: exchangeable, bound to carbonates, bound to Fe‐Mn oxides, bound to organic matter, and residual. Metal recoveries were within ± 10% of the independently measured total Cd, Cu, Ni, and Zn concentrations. The highest amount of Cd (ca. 37%) was foand in the exchangeable fraction, and Cu was the only metal significantly associated with the organic fraction. The Fe‐Mn oxide fraction contained 23, 24, 26, and 39%, and the residual fractions 15, 34, 55, and 14% of the Cd, Cu, Ni, and Zn, respectively. The amount of Cd in the residual fraction was 50 times higher than typical for unpolluted soils. Assuming that mobility and biological availability are related to the solubility of the geochemical form of the metals and decreases in the order of extraction, the apparent mobility and potential metal bioavailability for these highly contaminated soils and sediment is: Cd > Zn > Cu ≅ Ni.

Remediation of deltamethrin contaminated cotton fields: residual and adsorption assessment

“…This is in agreement with Zn associated [31][32]. The present study also shows a comparison of organic bound higher in sequence to exchangeable fraction with studies [27,33], as shown in Fig.…”

Chemical partitioning of iron, cadmium, nickel and chromium in contaminated soils of south-eastern Nigeria

“…This result is consistent with the results of many researchers who found the greatest percentage of nickel in the residual fraction (Gupta and Chen, 1975;Tessier et al, 2002;Hicky and Kittrik, 1984;Ma and Rao, 1997;Moral et al, 2005;Iwegbue, 2007;Chaudhary and Banerjee, 2007;Ogundiran and Osibanjo, 2009;Osakwe, 2010;Iwegbue, 2011). The majority of nickel in soils and sediments is distributed in nature (Gupta and Chen, 1975;Tessier et al, 1980;Hickey and Kittrick, 1984). Norrish (1975) has indicated that nickel is commonly occluded by silicate during soil weathering.…”

“…Tessier et al (1979) suggested that metal concentrations in the residual fraction of soils or sediments may be indicative of background metal levels. Heavy metals in the residual (HF-soluble) fraction are propbably associated with silicate minerals (Hickey and Kittrick, 1984). The next important fraction for iron is the carbonate fraction.…”

“…The organically complexes cadmium was relatively low. Low levels of cadmium in the organic fraction have been reported (Hickey and Kittrick, 1984).…”

Bioavailability of Some Heavy Metals in Selected Dumpsites in Ozoro, South-South, Nigeria

“…Adsorption has been noted as the important control of Copper in soils (Jenne, 1968;Hickey and Kittrick, 1984). The high surface area and adsorbing capacity of Fe-Mn oxide, coupled with the ability of Cu 2+ to replace Fe 2+ in some Fe-oxides (Taylor, 1965) may be responsible for such adsorption.…”