Determination of mercury in selected polluted sediments using HPLC-ICP-MS in Westbank area, Western Cape, South Africa

Abstract

High selectivity, excellent linearity and reproducibility were achieved using HPLC-ICP-MS method for mercury in sediments. The HPLC-ICP-MS method reported previously for mercury in biota analysis was adapted in terms of operational consumables and optimized for the efficient mercury determination in riverbed sediments; a first for South Africa. Results obtained for real environmental samples, were verified by Direct Mercury Analysis (DMA) by an accredited laboratory. The determination of inorganic and organic mercury compounds in sediments was based on the complexation of mercury compounds with cysteine. The separation was achieved on a reversed-phase C 18 column (15 cm × 4.6 mm id) using aqueous 0.1 % w/v L-cysteine·HCl + 0.1 % w/v L-cysteine mobile phase at a flow rate of 0.8 mL min -1 at ambient temperature. The method was found to be suitable for the routine analysis of Hg compounds in sediments as well as aqueous media and was developed to determine the influence of humic substances on the bioavailability of mercury species. The results were comparable and consistent with those determined with a Direct Mercury Analyzer. The detection limit for methylmercury, ethylmercury and inorganic mercury were lower than 10 ng L -1 and recoveries for spiked samples was >90 % . The accuracy of the method was assessed by the analysis of certified reference material (European Reference Material ERMCC580 and Tort-2) and found to be in good agreement. Mercury concentration was determined in sediments collected from the Eerste Kuils River, Westbank area, Kuilsriver, Western Cape, South Africa. Mercury concentration was determined to vary from 2-14 ng g -1 (w.wt).

Gas-Liquid Separator Modified on CV-AAS System for Determination of Total Hg in the Industrial Wastewater Samples

“…The problems can be overcome by modifying the shape and size of the commercial gas liquid separator (Panggabean et al, 2013). Gas liquid Separator modified was expected to improve the performance of measurement results to the maximum Several studies on determination of Hg in various samples using CV-AAS technique has been reported, such as: determination of Hg level in fish (Chen et al, 2013;Da Silva et al, 2019;Fashi et al, 2017;Zhu et al, 2017), groundwater and river using electrochemical CV-AAS technique (Karthika et al, 2019;Some et al, 2016), oil samples (Payehghadr et al, 2014;Veronesi et al, 2013;Vicentino et al, 2015), environmental samples (Gao et al, 2012;Le Roux et al, 2016;Oreste et al, 2013), hair (Domanico et al, 2017), determination of Hg level in honey, pollen, and greek bees (Maragou et al, 2016), and seafood using photochemical vapor generation capacitively coupled plasma microtorch optical emission spectrometry (Covaci et al, 2017), reported that the results obtained are valid and can be justified.…”

Determination of Total Mercury in Solid Samples by Anodic Stripping Voltammetry

“…Many methods have been reported for the determination of mercury such as high chromatography-inductively coupled plasma mass spectrometry (HPLC/ICP-MS) [13,14], gas chromatography-mass spectrometry (GC/MS) [2,15], graphite furnace atomic adsorption spectrometry (GF-AAS) [5,16,17], cold vapor atomic absorption spectrometry (CV-AAS) [3,9,18,19], cold vapor atomic fluorescence spectrometry (CV-AFS) [4,20,21], chemical vapor generation atomic emission spectrometry (CVG-AES) [22], UV-Vis spectrophotometric [23,24], and anodic stripping voltammetry (ASV) [25][26][27][28][29][30][31][32][33][34][35][36]. Compared to the ASV methods, the HPLC-MS and GC-MS methods require complex sample preparations and the use of toxic organic solvents (e.g., methanol and acetonitrile), and the analytical is also more complex.…”