Method Development and Sample Processing of Water, Soil, and Tissue for the Analysis of Total and Organic Mercury by Cold Vapor Atomic Fluorescence Spectrometry

Abstract

Abltract. Atomic Ruorescence-based metnods nave been developed for measuring ultratrace level. of mercury (Hg) in environmental (water, soil) and biological (fisn tissue) samplea. In addition, metnods for preparation of water, soil, and tinus samples nave been developed. For tne analysis of total Hg in soil, sediment and fisn tne samples are digested with concentrated nitric aCId in saaled glass ampulas, and subsequently autoclaved. Water samples are digested using standard brominating procedures. A Merlin Plus, PS Analytical atomic fluorescence spectromete, (AFS) system equipped with an autoaampler, vapor generator, fluorescence detector and a PC based integrator package ia used in tne determination of total Hg. Tne determinetion of Hg mercury species in water, witnout pra-derivatization, involves adsorbant pre-concentration of tne organomarcurials onto sulfydryl-cotton fibers. Tha organic Hg compounds are alutad with a small volume of acidic KBr and CuSO. and extracted into dichloromethane. Sediment, soil and tissua samples are homogenizad and the organomercurials first released from the sample by the combined action of ecidic KBr and CuSO. and extracted into dichloromethane. The initial extracts are subjected to tniosulfate clean-up and tne organomercury species are iaolated as tneir chloride derivatives by cupric chloride eddition anei subsequent extraction into a small volume of dichlorometnane. Analyais of organic Hg compounda is accomplisned by capillary column chromatograpny coupled witn atomic fluorescenca detection.

Bioaccumulation of inorganic and methylated mercury by the gills of the shore crab Carcinus maenas: transepithelial fluxes and histochemical localization

“…Exposure duration was either 0.5 or 2 h for each subgroup of 3 contaminated crabs, the 2 remaining uncontaminated subgroups of 3 crabs serving as controls. Then, the crabs were killed and posterior gill pairs (number 7 and 8) were removed, weighed and stored at -20°C before being digested with concentrated HNO 3 and analyzed for Hg content using cold vapor atomic fluorescence spectroscopy (SFA-Merlin-Plus, Seven Oaks, UK) (Jones et al 1995). Metal concentrations measured in gills from contaminated crabs were corrected by subtracting the values obtained in controls (mean value = 22 ng g -1 fresh weight).…”

Accumulation of total mercury and methylmercury in rice plants collected from different mining areas in China

“…Then the tissue was microwave digested (MARSX, CEM, USA). For THg in soil, ampule-sealing digestion was adopted (Jones et al, 1995;Liu et al, 2009). Approximately 0.1 g of soil was weighed into a 20 mL ampoule, and then 2 mL of HNO 3 and 1 mL of ultrapure water were added.…”

Mercury in coastal watersheds along the Chinese Northern Bohai and Yellow Seas

“…The [Hg] in sediments and biota was determined using a modified version of US EPA method 7474 [34,35]. The [MeHg] in samples of biota was measured using acid (3 N HNO 3 ) or hot alkali (25% NaOH) digestion, solvent (CH 2 Cl 2 ) extraction and reverse extraction by water, ethylation and gas chromatography-cold vapor atomic fluorescence spectrometry (GC-CVAFS), which was developed by Liang et al [36].…”