RAPID SENSITIVE SPECIATION ANALYSIS OF BUTYLTIN AND PHENYLTIN COMPOUNDS IN WATER BY CAPILLARY GAS-CHROMATOGRAPHY ATOMIC-EMISSION SPECTROMETRY (GC-AES) AFTER IN-SITU ETHYLATION AND IN-LINER PRECONCENTRATION

A rapid, simple and sensitive method has been developed for the simultaneous determination of butyl- and phenyltin species in environmental waters. The ionic organotin compounds are ethylated in the aqueous phase using sodium tetraethylborate (NaBEt4) and extracted with hexane. A 25 mul aliquot of the extract is injected at a low temperature into a Tenax filled liner. After solvent venting the analytes are transferred onto the capillary column using programmed temperature vaporization (PTV) injection. Detection is done by means of a microwave induced plasma atomic emission detector (MIP AED). The method allows the determination of butyl- and phenyltin compounds in water samples down to the level of 0.1 ng/l (as Sn) while 50 ml of sample is sufficient for analysis. The accuracy of the method was confirmed by GC-AAS after chelation and Grignard derivatization.