Validation and inter-laboratory study of selective hydride generation for fast screening of inorganic arsenic in seafood

• Published in: Analytica chimica acta Vol. 1049; pp. 20 - 28
• Main Authors: Marschner, Karel, Pétursdóttir, Ásta H., Bücker, Patrick, Raab, Andrea, Feldmann, Jörg, Mester, Zoltán, Matoušek, Tomáš, Musil, Stanislav
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 21.02.2019; Elsevier BV
• Subjects: Algae; Arsenic; Arsine; Certified reference materials; High-throughput screening; Hydrides; Hydrogen peroxide; Inductively coupled plasma mass spectrometry; Inorganic arsenic; Interlaboratory comparison; Laboratories; Legislation; Mass spectrometry; Mass spectroscopy; Nitric acid; Reference materials; Reproducibility; Screening; Seafood; Seaweeds; Selective hydride generation; Selectivity; Speciation analysis; Interlaboratory comparison; Certified reference materials; Speciation analysis; Selective hydride generation; Inductively coupled plasma mass spectrometry; Inorganic arsenic
• ISSN: 0003-2670; 1873-4324
• DOI: 10.1016/j.aca.2018.11.036

It is advisable to monitor and regulate inorganic arsenic (iAs) in food and feedstuff. This work describes an update and validation of a method of selective hydride generation (HG) with inductively coupled plasma mass spectrometry (ICP-MS) for high-throughput screening of iAs content in seafood samples after microwave-assisted extraction with diluted nitric acid and hydrogen peroxide. High concentration of HCl (8 M) for HG along with hydrogen peroxide in samples of a same concentration as used for extraction leads to a selective conversion of iAs to volatile arsine that is released and transported to the detector. A minor contribution from methylarsonate (≈20% to iAs) was found, while HG from dimethylarsinate, trimethylarsine oxide is substantially suppressed (less than 1% to iAs). Methodology was applied to Certified Reference Materials (CRMs) TORT-3, DORM-3, DORM-4, DOLT-4, DOLT-5, PRON-1, SQID-1 and ERM-CE278k, in some of them iAs has been determined for the first time, and to various seaweed samples from a local store. The results were always compared with a reference method and selectivity of iAs determination was evaluated. An inter-laboratory reproducibility was tested by comparative analyses of six fish and four seaweed samples in three European laboratories, with good agreement of the results. The method of HG-ICP-MS is sensitive (limit of detection 2 μg kg−1 iAs), well suited for screening of large number of samples and selective at iAs concentration levels at which maximum limits are expected to be set into EU legislation for marine samples. [Display omitted] •Selective hydride generation (no chromatography) improved for iAs determination.•The method was validated for seafood samples with complex As speciation.•Sufficient selectivity and good inter-laboratory reproducibility was achieved.•The method is suited for fast screening of large sample sets in control laboratories.•New data on iAs content in Certified Reference Materials presented.