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A rapid extraction procedure has been developed for speciation of arsenic in chicken tissue. Water, methanol–water (1:1), and methanol–chloroform (1:1) were tested as extraction media. Individual use of an ultrasonic bath, a microwave oven, or an ultrasonic probe was not sufficient for quantitative recovery of As(III), dimethylarsinate, monomethylarsonate, As(V), and arsenobetaine in spiked samples of chicken tissue. A new extraction procedure using a methanol–water mixture and a microwave oven then an ultrasonic probe enabled extraction of the arsenic species in 7 min with efficiencies ranging from 80 to 100%. HPLC–UV–HG–AFS was used for the determinations. The extraction procedure was 100% efficient when applied to real samples of chicken tissue. AsB (48±5 μg As kg −1) and one containing-arsenic feed additive, Nitarsone (227±5 μg As kg −1) were detected. [ABSTRACT FROM AUTHOR]

A preservation study has been performed for arsenic speciation in surface freshwaters affected by acid mine drainage (AMD), a pollution source characterized by low pH and high metallic content. Two sample preservation procedures described in the literature were attempted using opaque glass containers and refrigeration: i) addition of 0.25 mol L−1 EDTA to the samples, which maintained the stability of the arsenic species for 3 h; and ii) in situ sample clean-up with a cationic exchange resin, in order to reduce the metallic load, which resulted in a partial co-adsorption of arsenic onto Fe precipitates. A new proposed method was also tried: sample acidification with 6 mol L−1 HCl followed by in situ clean-up with a cationic exchange resin, which allowed a longer preservation time of at least 48 h. The proposed method was successfully applied to water samples with high arsenic content, taken from the Aguas Agrias Stream (Odiel River Basin, SW Spain), which is severely affected by AMD that originates at the nearby polymetallic sulfide mine of Tharsis. The speciation results obtained by liquid chromatography–hydride generation–atomic fluorescence spectrometry (HPLC-HG-AFS) indicated that during the summer the main arsenic species was As(V) at the hundred μg L−1 level, followed by DMA (dimethyl arsenic) and As(III) below the ten μg L−1 level. In winter, As(V) and As(III) increased at least fivefold, whereas the DMA was not detected. [ABSTRACT FROM AUTHOR]

An arsenic chemical speciation study was performed in 2000, using air filters on which total suspended particles (TSP) were collected, from the city of Huelva, a medium size city with huge industrial influence in SW Spain. Different procedures for extraction of the arsenic species were performed using water, NH2OH.HCl, and H3PO4 solutions, with either microwave or ultrasonic radiation. The best optimised extraction methods were use of 100 mmol L−1 NH2OH.HCl and 10 mmol L−1 H3PO4 and microwave radiation for 4 min. High-performance liquid chromatography coupled with hydride generation and atomic fluorescence spectrometry (HPLC–HG–AFS) was employed for determination of the arsenic species. The results from 12 TSP air filters collected on a monthly basis showed extraction was quantitative (94% with NH2OH.HCl and 86% H3PO4). Only inorganic arsenic species (arsenite and arsenate) were detected. The mean arsenite concentration was 1.2±0.3 ng m−3 (minimum 0.3 ng m−3, maximum 1.8 ng m−3). The mean arsenate concentration was 10.4±1.8 ng m−3, with greater monthly variations than arsenite (minimum 2.1 ng m−3, maximum 30.6 ng m−3). The high level of arsenic species in the TSP samples can be related to a copper smelter located in the region. [ABSTRACT FROM AUTHOR]