Muhammad Waris, Jameel Ahmed Baig, Hassan Imran Afridi, Tasneem Gul Kazi and Sadaf Parveen
The present research assesses the chemical fractionation of cadmium (Cd), chromium (Cr), and lead (Pb) detected in saline soil samples of Hyderabad Pakistan. Based on the reagents used in the BCR three step sequential extraction scheme (BCR-SES) for partitioning Cd, Cr, and Pb in saline soil samples, a Microwave single step extraction (MSE) method was developed. The validity of the methods was confirmed using certified reference material (CRM) BCR-701 and the standard method of addition (recoveries 96-102%). The data provided by the BCR-SES method for Cd, Cr and Pb were compatible with MSE using the same operating conditions applied and checked in BCR fraction by the Certified Reference Material (CRM) BCR 701. Atomic absorption spectrometry was used to test extractable Heavy Metals (HMs) substances obtained by comparative method. Using compromised sonication and microwave conditions, steps 1–3 of the sequential extraction (excluding hydrogen peroxide digestion in step 3) could be accomplished with ultrasonic bath between 15–30 min, whereas 60–120 s were needed for MSE. The total concentrations of Cd, Cr, and Pb extractable metals produced by three separate extractions ranged from 1.02-3.30, 5.02-9.95 and 3.97-8.01 μg/g respectively. The accuracy of the proposed BCR single extraction procedure (RSD %) for all metals was found within the % range from 4.91–8.61% respectively.
