Gas Chromatographic Determination of Methyl Mercury in Fish, Sediment, and Water

Abstract

Methyl mercury is extracted as the bromide salt from fish and sediment and as the chloride salt from water samples. All extracts are treated with a common cleanup procedure that results in the conversion of methyl mercury to the iodide salt for electron capture gas chromatographic analysis. Recoveries ranged from an average of 88.5% for water samples to averages of 95.5 and 96.3% for perch and sediments. Methods for controlling contaminants and interferences are discussed for all phases of the method. Particular problems encountered were column poisoning and detector poisoning. When the method was applied to sediment samples collected from a polluted river, a correlation could be established between total mercury and methyl mercury when the concentration of total mercury was in the 0–10 μg/g region. For samples of very high inorganic mercury, the correlation failed.

Sulfate-Reducing Bacteria: Principal Methylators of Mercury in Anoxic Estuarine Sediment

“…Mercury was added as the bichloride (HgCI2) at 75 ,ug g ofdry sediment-1. After incubation at 25°C, the slurries were extracted by the method of Longbottom (13), and monomethylmercury was determined by gas chromatography with electron capture detection (5…”

Production of methyl mercury in the gut of the Australian termite Mastotermes darwiniensis

“…For solvent extraction a 1 mol/l copper sulphate (pro analysi, Merck) solution and a 3 mol/l potassium bromide (pro analysi, Roth, Karlsruhe, Germany) solution in 10% (v/v) sulphuric acid (p.a. Roth) were prepared as described by Longbottom et al (1973).…”

“…Methyl mercury concentration in biological samples was determined by purge-and-trap CGC-AFS after acid solvent extraction with CuSO 4 and KBr/H 2 SO 4 and aqueous-phase propylation (Longbottom et al 1973;Liang et al 1996;Qian et al 2000). However, this method showed unsatisfactory reproducibility of the signal intensities.…”

“…Methyl mercury concentration was determined by purge-and-trap capillary gas chromatography coupled with atom fluorescence spectrometry (CGC-AFS) after acid solvent extraction with CuSO 4 and KBr/ H 2 SO 4 and aqueous-phase alkylation (Longbottom et al 1973;Liang et al 1996;Qian et al 2000) using ethyl mercury as the internal standard. Total mercury was determined in the termite tissue by inductively coupled plasma-isotope dilution mass spectrometry (ICP-IDMS) after microwave-assisted digestion.…”

The Degree of Methylation and Organ Distribution of Mercury in Some Birds of Prey in Norway

“…The methyl mercury concentrations were determined by gas chromatography (Uthe et al 1972;Longbottom et al 1973;0Mand et al 1977). 0.5 g of sample was homogenized with sulphuric acid, copper sulphate, and potassium bromide in a 12 ml centrifuge type tissue grinder with screw cap (Bellco Glass Inc.) and extracted twice with toluene.…”