Experimental study on the unintentional abiotic methylation of inorganic mercury during analysis: Part 1: Localisation of the compounds effecting theabiotic mercury methylation

An attempt was made to investigate the causes and factors involved in methy l mercury formation during analysis. A hyphenate HPLC-UV-PCO-CVAFS and a HP LC-ICP-MS technique was used in the completion of the isotope experiments. All mercury methylation experiments were carried out under conditions simil ar to those of the water vapour distillation method. The sample matrices, w hich showed the highest artefact formation potential, were further investig ated using different extraction methods. The compounds responsible for high er artefact formation were especially well extractable using polar organic solvents such as acetone and acetonitrile and less soluble in nonpolar solv ents such as toluene and hexane. The extracts were further separable with t hin layer chromatography and with the aid of a packed liquid chromatography column. Methylation experiments using different model compounds of metabol isms from humic substances were carried out to give an idea of the compound s responsible for the methyl group transfer to inorganic mercury. (C) 1999 Elsevier Science Ltd. All rights reserved.