CHARACTERISTICS OF THE ATOMIC FLUORESCENCE SIGNALS OF ARSENIC IN SPECIATION STUDIES

The behaviour of the arsenic hydrides, generated after the speciation of AsIII (arsenite), MMAs (monomethylarsonate) and DMAs (dimethylarsin ate), in an atomic fluorescence cell was investigated. The efficiency of the hydride generation process was measured by inductively coupled plasma atomic emission spectrometry (ICP-AES) after sampling the liqui d drain of the gas-liquid separator and by a gas chromatograph with ma ss spectrometric detection (GC-MS) for the analysis of the sampling ga s of the separator. The different concentrations at which the fluoresc ence signal reaches a maximum were determined for each As species. (C) 1997 Elsevier Science B.V.