Robust ultrasound assisted extraction approach using dilute TMAH solutions for the speciation of mercury in fish and plant materials by cold vapour atomic absorption spectrometry (CVAAS)

M V Balarama Krishna,D Karunasagar

doi:10.1039/c4ay02114b

Abstract

A simple and robust ultrasound assisted extraction (UAE) protocol with dilute solutions of tetramethyl ammonium hydroxide (TMAH) for the speciation of mercury in fish and plant tissues was developed by CVAAS as an alternative to conventional methods.

Highlights

Mercury is a global pollutant and highly toxic among heavy metals because of its persistence, long range transport potential and bioaccumulation in the environment
The supernatant was analysed for the determination of residual mercury by cold vapour atomic absorption spectrometry (CVAAS), and the results indicated the absence of mercury
The present study was focussed on the determination of only inorganic and methyl mercury species

Summary

Introduction

Mercury is a global pollutant and highly toxic among heavy metals because of its persistence, long range transport potential and bioaccumulation in the environment. Mercury is introduced in the environment mainly as elemental mercury (Hg0), inorganic mercury (iHg) and organic mercury species as a result of both natural and anthropogenic activities from where it reenters the human food chain.[1,2,3,4,5,6,7] More than 2500 tons of mercury is emitted annually from global anthropogenic sources, which are signi cantly contributing to elevated levels of mercury. These two are the common and predominant forms of mercury generally found in biological and environmental samples such as sh tissues and plant matrices.[9,10,11,12,13] Because of the accumulative properties and adverse toxic effects of mercury species even at ultra-trace levels, As a consequence, considerable efforts and progress have been made in the development of sensitive and accurate sample preparation methods for the determination of total mercury and its speciation analysis in environmental and biological samples.[14,15,16,17,18,19,20,21,22,23,24,25,26] The most frequently used approaches for the extraction of mercury species from sh and plant samples are based on microwave[27,28,29,30] or ultrasound[31,32] assisted alkaline or acid leaching and solid phase extraction.[33,34] Despite excellent sensitivity and selectivity, most of the abovementioned approaches suffer from major limitations that include laboriousness of the procedures, use of high amount of acids along with complexing agents, lack of acceptable efficiency and long time consumption

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Results

Conclusion