Determination of Methylmercury and Butyltin Compounds in Marine Biota and Sediments Using Microwave-Assisted Acid Extraction, Solid-Phase Microextraction, and Gas Chromatography with Microwave-Induced Plasma Atomic Emission Spectrometric Detection

Abstract

A method is described for the determination of methylmercury and butyltin compounds in marine sediment and tissue using microwave-assisted acid extraction or digestion and solid-phase microextraction (SPME) followed by analysis using gas chromatography with microwave-induced plasma atomic emission spectrometric detection (GC-MIP-AES). Using the SPME-GC-MIP-AES method, enrichment factors for methylmercury and butyltin compounds of 50-100 were achieved, as compared to the typical hexane extraction, and measurements in marine tissue and sediment matrixes were possible at 1-2 microg/kg (methylmercury) and 10-100 ng/kg (butyltins). The SPME-GC-MIP-AES method was validated using several marine sediment and tissue matrix certified reference materials (CRMs) with certified values for methylmercury and butyltin compounds. The SPME-GC-MIP-AES method was used to measure methylmercury in four marine tissue CRMs ranging from oyster tissue at 13.0 +/- 1.0 microg/kg to fish tissue at 397 +/- 13 microg/kg (as Hg dry mass). Results from the SPME-GC-MIP-AES method were used in conjunction with results from other techniques to assign certified values for methylmercury in oyster, mussel, and fish tissue CRMs. Mono-, di-, and tributyltin were measured in three sediment CRMs at concentration levels of (0.08 +/- 0.03)-(0.35 +/- 0.05) mg/kg (as Sn dry mass).

Determination of methylmercury in fish tissues by isotope dilution SPME-GC-ICP-MS

“…[15][16][17] Grignard reagents, [18][19][20][21] sodium tetraethylborate (NaBEt 4 ), 17,[22][23][24][25][26] sodium tetrapropylborate (NaBPr 4 ) 18,27 and sodium tetraphenylborate (NaBPh 4 ) [28][29][30][31][32][33] have been used for efficient derivatization. Gas chromatography, capillary electrophoresis or liquid chromatography are commonly used separation techniques for MMHg speciation in combination with atomic fluorescence spectrometry (AFS), 3,[34][35][36] electron-capture detection (GC-ECD), 37 atomic absorption spectrometry (AAS), 16,22 ion trap mass spectrometry, 30,31 inductively coupled plasma and microwave-induced plasma atomic emission spectrometry (ICP-AES, MIP-AES) 14,21,[38][39][40][41] and inductively coupled plasma mass spectrometry (ICP-MS) detection. 18,24,36,40,42,43 Over the past decade, the coupling of GC to ICP-MS has become a particularly popular technique for speciation work due to the high temporal resolution offered by GC and the high sensitivity, large dynamic range and multi-elemental capability of ICP-MS. On the other hand, sam...…”

Isolation and quantification of dialkylmercury species by headspace solid phase microextraction and gas Chromatography with Atomic Emission detection

“…In contrast, the extracted amounts are substantially higher for P100 fibers, due to the non-polar coating (polydimethylsiloxane) of this fiber; which up to the present has been the fiber most frequently employed for extractions of the alkylmercury compounds. [19][20][21] Higher efficiencies are possible with the DVB and CAR fibers. Since the coatings of these fibers are dispersions of solids (divinylbenzene and Carboxen 1006, respectivelly) in polydimethylsiloxane, both adsorption and partition occurs during the extraction.…”

Plasma-source mass spectrometry for speciation analysis: state-of-the-art

“…Analysis of pesticides by this method is particularly attractive because the microwave plasma is capable of generating simultaneous quantitative information for carbon-, chorine-, sulfur-and phosphorous-containing molecules or can provide molecular ions to help identify the parent pesticide species [139]. In addition, a vast number of studies have focused on speciation of volatile compounds by coupling the microwave plasma with gas chromatography for the determination of arsenic [140], mercury [141][142][143], tin [141,142], and selenium [144], to name a few. A number of reviews have been prepared to cover speciation of a wide range of elements by MIPs and their use in both emission and mass spectrometry [134,145,146].…”