Determination of arsenic, selenium and mercury in fish samples by slurry sampling electrothermal vaporization inductively coupled plasmamass spectrometry

Abstract

Ultrasonic slurry sampling–electrothermal vaporization inductively coupled plasma mass spectrometry (USS–ETV-ICP-MS) was applied to the determination of Ge, As, Se and Hg in several fish samples. The influences of instrument operating conditions and slurry preparation on the ion signals were investigated. Palladium and thioacetamide were used as modifiers to reduce the loss of Hg during drying. Since the sensitivities of Ge, As, Se and Hg in various fish slurries and aqueous solution were different, the standard additions method was used for the determination of Ge, As, Se and Hg in these fish samples. This method was applied to the determination of Ge, As, Se and Hg in dogfish muscle reference material (DORM-2), dogfish liver reference material (DOLT-1) and a commercial swordfish sample. The results were agreed with the certified values. The precision between sample replicates was better than 11% with the USS–ETV-ICP-MS method. Detection limits calculated from standard addition curves were about 7, 19, 31 and 34 ng g^–1 for Ge, As, Se and Hg, respectively, in different samples.