Comparison of the extraction efficiencies of four different solvents used in trace metal digestion of selected soils within Abakaliki, Nigeria

Journal of Applied Sciences and Environmental Management

CHUKWU, EBUBE REBECCA¹  OFFOR, IFEANYI FRANCIS¹  OMAKA, NDUKAKU OMAKA¹  EWUZIE, UGOCHUKWU¹ 

关键词: Extraction;    Soils;    Pollution;    Trace metals;    Abakaliki;   

DOI  :  

学科分类：环境科学（综合）

来源: University of Port Harcourt * Department of Pure and Industrial Chemistry

【 摘 要 】

Soil pollution by trace metals is one of the major global environmentalchallenges facing us today. Extraction methods are key to predicting plant uptake of tracemetals from soil. This work seeks to compare the extraction efficiencies of EDTA, DTPA,HNO3/HClO4 and HCl/HNO3 used in the digestion of soil samples collected from 11 differentlocations (7 farmlands, 2 waste dumpsites and 2 sections of a mechanic workshop) withinAbakaliki metropolis, between August and September 2007. Concentrations of 7 selectedtrace metals (Pb, Zn, Mn, Ni, Cd, Cu and Fe) were determined in the digested soil samplesusing atomic absorption spectrophotometer. The concentrations (mg/kg) range, irrespective ofsampling sites were: Pb (2.85-43.07; 1.42-11.49; 3.83-131.90; 1.98-184.12), Zn (0.02-3.98;0.01-0.79; 2.25-13.22; 0.15-39.45), Mn (1.33-78.83; 0.38-14.85; 1.02-66.24; 0.84-104.39), Ni(1.15-14.10; 0.07-2.57; 2.09-49.70; 5.10-92.72), Cd (0.03-2.79; 0.01-0.61; 0.25-9.20; 0.15-3.68), Cu (1.59-79.96; 0.65-14.33; 1.02-184.68; 1.60-134.10), Fe (6.62-149.44; 0.39-12.22;44.95-375.27; 7.48-548.32) using EDTA, DTPA, HNO3/HClO4 and HCl/HNO3 respectivelyas extractants. Results revealed that all extractants showed strong positive correlation inbringing only Cd into solution. ANOVA depicted no significant difference in mean tracemetals contents of soils from mechanic workshops as extracted with all solutions, while otherlocations did. For risk assessment, only Cd, Ni and Pb had their values within the regulatorylimits, whereas others were above the limits in all samples from different locations.

【 授权许可】

Unknown