A Green Analytical Procedure for Sensitive and Selective Determination of Arsenic in Scalp Hair Samples of Arsenic Exposed Adults of Both Genders

Abstract

A green analytical procedure based on cloud point extraction (CPE) is proposed for arsenic determination in biological samples (scalp hair). The scalp hair samples were subjected to microwave assisted digestison in a mixture of nitric acid and hydrogen peroxide (2:1 ratio), prior to preconcentration by CPE. Arsenic in digested samples of scalp hair was formed complex with ammonium pyrrolidine dithiocarbamate (APDC), and resulted As-PDC complex was extracted by a non-ionic surfactant octylphenoxypolyethoxyethanol (Triton X-114), after centrifugation the surfactant-rich phase was diluted with 0.1 mol L−1 HNO3 in methanol. For optimum recovery of analyte, the influence of the analytical parameters including pH, amounts of complexing and surfactant reagents were investigated. An enrichment factor of 50 was obtained for the preconcentration of As. Limit of detection and quantitation obtained under the optimal conditions were 0.03 and 0.11 µg kg-1, respectively. The obtained result showed sufficient recovery (> 98%) for As in certified reference material of human hair (BCR 397). The developed method was applied to the determination of As in scalp hair samples of male and female subjects of two villages of Hyderabad, Pakistan.

Keywords

• Arsenic
• Cloud point extraction
• Scalp hair samples
• Electrothermal atomic absorption spectrometry.