Simultaneous multi-elemental speciation of As, Hg and Pb by inductively coupled plasma mass spectrometry interfaced with high-performance liquid chromatography.

ABSTRACT

This work establishes a hyphenated methodology coupling HPLC with ICP-MS for simultaneous speciation analysis of arsenic, mercury and lead for the first time. Four arsenicals (As(III), DMA, MMA and As(V)), four mercurials (Hg(II), MeHg, EtHg and PhHg) and three lead compounds (Pb(II), TML and TEL) were simultaneously analyzed within only 8 min with acceptable resolution (2.0-8.2 for As, 1.6-6.1 for Hg and 2.7-4.0 for Pb). The detection limits were 0.036-0.20 for As-species, 0.023-0.041 for Hg-species, and 0.0076-0.14 µg L-1 for Pb-species. The developed method was applied for the measurement of five lotus seed samples, indicating the presence of DMA (19.6-28.2 µg kg-1), TML (1.4-2.9 µg kg-1), MeHg (1.2-4.8 µg kg-1) and EtHg (0.8-2.2 µg kg-1). This method provides a promising tool for studying the toxic, metabolic and bioavailable behaviors of arsenic, mercury and lead.