Mercury distribution in a polluted marine area, ratio of total mercury, methyl mercury and selenium in sediments, mussels and fish

In this study, the analysis of methyl mercury (MeHg) and total mercury (T-Hg) was studied using gas chromatographic separation/atomic fluorescence spectrometric detection and cold vapour atomic absorption spectrometry respectively. MeHg was extracted from sediment matrix using HNO3/KCl/CuSO4 into dichloromethane followed ethylation with NaB(C2H5)4 in hexane. Total mercury was digested using three different procedures: EPA 245.1, AOAC 971.21 and our proposed one. The reliability of the analytical method for MeHg was evaluated by the use of the certified reference material ERM CC-580. In addition, the analytical method for total merury was evaluated using a fresh water sediment as an internal reference material, spiked with inorganic mercury, methyl mercury and phenyl mercury. The method detection limits for MeHg and total mercury were 0.08 and 0.15 ng/g (as Hg), respectively. The established analytical methods were applied to analyse MeHg and total mercury in sediment samples collected from canals and rivers in Hochiminh City. The concentrations of methyl mercury and total mercury in sediment samples were 0.08–2.87 ng/g và 14 – 623 ng/g (as Hg, dw). [MeHg]/Σ[Hg] respectirely were in a range of 0.1–2.3 %, which was in good agreement with the published ratios in sediment samples. A good correlation between the concentration of MeHg with total mercury and total organic carbon contents in the studied sediment samples was found.

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A Comparison of Mercury Contamination in Mussel and Ammocoete Filter Feeders

Journal of Fish and Wildlife Management ◽

10.3996/112009-jfwm-019 ◽

2010 ◽

Vol 1 (2) ◽

pp. 142-145 ◽

Cited By ~ 7

Author(s):

Jamie B. Bettaso ◽

Damon H. Goodman

Keyword(s):

Methyl Mercury ◽

Total Mercury ◽

Mercury Contamination ◽

Teleost Fishes ◽

Trinity River ◽

Longitudinal Gradients ◽

History Of ◽

Filter Feeders ◽

The Trinity ◽

Mercury Mining

Abstract The Trinity River, California, has an extensive history of gold and mercury mining, and recent studies demonstrated uptake of legacy mercury contamination by teleost fishes. We investigated mercury concentrations of larval lampreys (ammocoetes; Entosphenus spp.) and western pearlshell mussels (Margaritifera falcata) in the Trinity River to determine whether these two long-lived and sedentary filter feeders show site-specific differences in uptake of this contaminant. We analyzed ammocoetes from four sites in the Trinity River and one reference site in the Mad River for total mercury and mussels from three of the Trinity River sites for total and methyl mercury. We identified longitudinal gradients in ammocoete total mercury levels and methyl mercury in mussels. We found a 70% increase in total mercury in ammocoetes between two of the sample sites, suggesting a potential point source of contamination. Ammocoetes contained levels of mercury 12 to 25 times those of mussels from the same site. Our data indicate that ammocoetes may be a preferred organism to sample for mercury contamination and ecological effects compared with mussels in the Trinity River.

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Rapid Semimicro Method for the Determination of Methyl Mercury in Fish Tissue

Journal of AOAC INTERNATIONAL ◽

10.1093/jaoac/55.3.583 ◽

1972 ◽

Vol 55 (3) ◽

pp. 583-589 ◽

Cited By ~ 8

Author(s):

J F Uthe ◽

J Solomon ◽

B Grift

Keyword(s):

Gas Chromatography ◽

Thin Layer ◽

Methyl Mercury ◽

Total Mercury ◽

Aqueous Ethanol ◽

Fish Tissue ◽

Mercuric Iodide ◽

Mercury In Fish ◽

Layer Chromatography

Abstract A fast semimicro method for the determination of methyl mercury in fish tissue is described. The procedure involves extracting the methyl mercury into toluene as methyl mercuric bromide, partitioning the bromide into aqueous ethanol as a thiosulfate complex, and re-extracting into benzene as methyl mercuric iodide. Methyl mercury is quantitated with gas chromatography. The method is sensitive to 0.01 ppm. Recoveries of added methyl mercury were 99% and the presence of methyl mercury in the final extract was shown by thin layer chromatography and gas chromatography of the thin layer spot. A variety of mercurial compounds do not interfere in the analyses. The amounts of both methyl and total mercury found in a variety of tissues of aquatic animals are compared. The presence of a demethylase in seal is suggested by the findings of high levels of nonmethyl mercury. Additional cleanup by column chromatography on Florisil was necessary with certain samples. The gas chromatographic columns were kept operational by the intermittent injection of 3M potassium iodide. Due to column bleed and resulting detector contamination, the use of the easily cleaned concentric tube electron capture detector is recommended.

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