Determination of methylarsenic compounds in airborne particulate matter by gas chromatography with atomic absorption spectrometry

A sensitive method is described for the determination of mono-, di- and tri-methylarsenic compounds in airborne particulate matter by hydride-generation and gas-liquid chromatography with atomic absorption spectrometric detection. Interferences of various species are discussed. Absolute detection limits are 70, 80 and 100 pg As, respectively for the mono-, di- and tri-methylarsenic species. Recoveries of methylarsenic compounds added to airborne particulate matter are almost 100%. An iron/nitrate mixture interfered strongly but this was overcome by adding EDTA.