Speciation of arsenic in fish tissue using microwave-assisted extraction followed by HPLC-ICP-MS

The use of microwave-assisted extraction for the extraction of arsenic species from fish tissue is described. Quantitative extraction of arsenic from spiny dogfish muscle (CRM, DORM-2) was achieved using methanol-water (80 + 20, v/v) with microwave heating at 65 degrees C in a closed-vessel microwave system. Extractions were performed with a variety of solvents including water, two different methanol-water mixtures, and a 5% tetramethylammonium hydroxide solution. Extracted arsenic species were separated using both ion-exchange and ion-pair chromatography with ICP-MS detection. The DORM-2 along with three different varieties of fish purchased from a local market were analyzed for arsenic. In all samples, the majority of arsenic present was in the form of arsenobetaine, a nontoxic arsenic species.