MERCURY SPECIES IMMOBILIZED ON SULFHYDRYL COTTON - A NEW CANDIDATE REFERENCE MATERIAL FOR MERCURY SPECIATION

A batch of sulphydryl cotton microcolumns was prepared and charged wit h a mixed Hg standard solution (methyl-, ethyl- and inorganic HE, 10 m u g l(-1) as Hg, 3 mi) and stored at 4 degrees C in a light-tight box. At regular time intervals over a 4 month period microcolumns were rem oved and Hg species were quantified by gas chromatography microwave-in duced plasma atomic emission spectrometry (after elution, extraction a nd derivatization steps). It was found that analyte recoveries for met hyl- and inorganic HE were quantitative over the 4 month period while ethyl-Hg species appeared to be stable for up to 2 months.