Speciation and determination of tin(IV) and organotin compounds in sea-water by hydride generation-atomic-absorption spectrometry with an electrically heated long absorption cell

A method is described for the determination of nanogram or subnanogram amounts of Sn(IV) and the halides of methyltin, dimethyltin, trimethyltin, n-butyltin, dibutyltin, and tributyltin. These compounds are volatilized from water samples by hydride generation, collected on a chromatographic stationary phase, desorbed in order of increasing boiling point, and detected by atomic-absorption spectrometry with atomization in a long electrothermally heated alumina tube furnace. The absolute detection limits are in the range 0.4-1.5 ng with a reproducibility of 4-15% for inorganic tin and organotin compounds.