Development of analytical procedure for the determination of methyltin, butyltin, phenyltin and octyltin compounds in landfill leachates by gas chromatography-inductively coupled plasma mass spectrometry

Graphical abstract: Highlights: → Methyl-, butyl-, phenyl- and octyl-tins in landfill leachates was determined. → Simultaneous determination based on GC-ICP-MS. → Procedure enables routine monitoring of organotins in landfill leachates. - Abstract: Landfilling is the most common disposal of municipal waste. During the decomposition of different waste materials, several toxic compounds are leached. Although organotin compounds (OTC) represent an important group of pollutants in landfill leachates, there are only few analytical procedures reported for their analysis. These procedures are complex or recommend the use of enriched stable isotopes that are available only for butyltins. In the present work analytical procedure for simultaneous routine speciation analysis of methyl-, butyl-, phenyl- and octyl-tins in landfill leachates by GC-ICP-MS was developed. For this purpose the applicability of methanol as co-extraction reagent and Tris-citrate buffer for adjustment of pH for derivatization of OTC in landfill leachates was carefully investigated. The use of NaBEt4 and NaBPr4 as derivatization reagents for liquid-liquid extraction into hexane was critically evaluated. 15 m GC column was used for rapid separation of OTC. The developed analytical procedure was sensitive (LODs for OTC investigated in general better than 2 ng Sn L-1) with good repeatability of measurement (RSDs mostly better than 3%) and was successfully applied in the analysis of OTC in landfill leachates using standard addition calibration method. Due to its simplicity and reliability it is appropriate to be used in routine laboratories for monitoring of OTC in landfill leachates.