My research area focuses on the development and application of analytical methods/techniques for speciation analysis of inorganic and organometalic compounds of Sn and As. The analytical techniques used are based on hyphenation of chromatographic separation (HPLC, GC) and spectrometric detection (MS, ICP-MS, AAS) methods. Calibration methodologies based on species specific isotope dilution are employed to follow and correct for the transformation/degradation that can take place, often unavoidable, during the analysis of organotin compounds.