Determination of Heavy Metals in Two Regions from Kirkuk City Using Sequential Extraction

Abstract

Soil is a major reservoir for heavy metals and other contamination as it possesses an ability to absorb these metals on the surface of clay minerals and bind various chemicals. These heavy metals and chemicals can exist in various forms in soil and different forces keep them bound to clay minerals and soil particles. The aim of the present work is to estimate the concentration levels of some heavy metals Zn, Cu, Pb and Cd in two sites of soil Kirkuk city. In this study the first sample was taken from inside the city of four areas around (Northern Oil Company) in Kirkuk city, while the second sample was taken from outside the city of four areas and both were randomly chosen. Sequential extraction procedure was applied to fractionate heavy metals which may help in the prediction of their mobility, bioavailability and fate of the metal contaminant. Results of sequential extraction showed that Cd and Pb were mainly bound to residual fraction, Cu was mainly bound to organic fraction and Zn was bound to Fe-Mn oxide fraction in the two sites of the study. The overall mean values obtained for the metals in the fractions gave the range: inside the city Cu (28.12 ppm), Zn (77.9 ppm), Pb (21.73 ppm) and Cd(4.21 ppm), and outside the city Cu (24.65 ppm), Zn (59.28 ppm), Pb (13.25 ppm) and Cd (2.38 ppm). The extracts were analyzed for heavy metal, using flameless-atomic absorption spectrophotometers (Flameless-AAS).

Evaluation and Speciation of Heavy Metals Contamination of Selected Artisanal Mining Sites in Mangu Local Government Area of Plateau State, Nigeria

“…This is similar to the reports of other researchers [13]. Hussain [34] and Ochiagha et al [12] reported that heavy metals that are mostly bound to the residual fraction are not easily bioavailable to plants in the environment. The distribution of Zn on the order hand at Mangu Halle and Alogwom follows the pattern: residual fraction > Fe/Mn bound fraction > carbonate fraction > soluble fraction > exchangeable fraction.…”

“…The predominance of Cd in the mobile fractions (soluble and exchangeable fractions) has been reported [13], [33]. The high percentage of Cd in the mobile fractions (62.78%) poses serious potential threat to the ecosystem and enhance potential bioavailability [14], [34]. The association of Cd follows the order: exchangeable fractions > soluble fraction > carbonate fraction > Fe/Mn bound fraction > residual fraction at Mangu Halle while at Alogwom, the distribution follows the pattern: exchangeable fractions > soluble fraction > residual fraction > Fe/Mn bound fraction > carbonate fraction.…”

Determination of the Zinc level in Environmental and Biological Samples in Baiji City by Atomic Absorption Spectrophotometer

“…The chemical materials in procedure used as same as tessier scheme. The procedure pertionally Zinc into the following five fractions [11].…”

“…Zinc was determined in human blood for medical diagnosis [9], while in the environmental samples (water and soil), the Zinc concentration was determined to access the pollution index [10]. The total Zinc concentration in the biological and environmental samples does not indicate the fact of diagnosis and pollution [11]. The speciation of Zinc in soil was studied using Tessier Schem [11,12].…”

“…The total Zinc concentration in the biological and environmental samples does not indicate the fact of diagnosis and pollution [11]. The speciation of Zinc in soil was studied using Tessier Schem [11,12]. to determine Zinc in ion exchangeable, carbonate, Fe-Mn oxide, organic, and residual layers.…”