Speciation of methyl- and inorganic mercury in biological tissues using ethylation and gas chromatography with furnace atomization plasma emission spectrometric detection

A sensitive and interference-free method for the quantification of inorganic and methylmercury species in biological tissues is presented using purge-and-trap injection-GC-AES, Samples were solubilized with tetramethylammonium hydroxide and the ionic species were purged from aqueous solution after ethylation with sodium tetraethylborate. The species were preconcentrated on Tenax-TA and thermally desorbed onto an isothermal (90 degrees C) GC column packed with 15% OV-3 on Chromasorb W, The separated species were eluted in He to a FARES source for detection by AES at 253.6 nm, Absolute detection limits of 1 and 7 pg for inorganic and methylmercury, respectively, can be obtained, corresponding to concentration LODs of 0.2 and 1.4 ng g(-1), respectively, in solid tissue samples. Precision of determination is better than 10% RSD, The accuracy of the technique was validated by the analysis of National Research Council of Canada CRMs DORM-2, DOLT-2 and TORT-2, certified for mercury species content.