Determination of organomercury compounds with a miniaturised automated speciation analyser Original Research Article

The automated speciation analyser (ASA) is a newly developed instrument for speciation analysis of environmentally and toxicologically interesting elements on routine basis. The instrument is based on a combination of a purge and trap concentrator, an isothermal oven housing a multicapillary column for the separation of the analytes and a miniature microwave induced plasma emission detector. This work describes the optimisation of the ASA for the determination of methylmercury and inorganic mercury leading to absolute detection limits of 4 and 9 pg for MeHg+ and Hg2+, respectively, and relative detection limits of 0.4 and 0.8 pg ml−1, which is satisfactory for environmental purposes. Furthermore, this instrument has the advantage of being small, robust and easy to handle and allows fast analysis. The optimised system was validated by the determination of MeHg+ in CRM 464 reference material and demonstrated for the determination of methylmercury and inorganic mercury in North Sea water.