A novel technique for direct derivatization of ionic organotin and alkyl-lead compounds in sediment : Simultaneous determination of organotin and alkyl-lead compounds in sediment by gas chromatography-plasma atomic emission (GC-AED) dual-channel detection

A direct derivatization carried out on sediment slurries and simultaneous speciation of organotin and alkyl lead in sediments is described. Simultaneous determination was performed using dual-channel operation of the AED detector. Direct contact of phentylmagnesium bromide with the sediment improved drastically the recovery of the monobutyltin (MBT) species. The combined complexation/extraction/derivatization procedure and the dual-channel AED operation reduced the analysis time. Analysis of a Certified Reference sediment, PACS-1, demonstrated the accuracy of the method. The absolute detection limits (3 x noise level) are 0.5 pg and 0.2 pg respectively for tin and lead. The relative detection limits for sediment (1 g sample) are 2.5 ng g -1 and 1 ng g -l respectively for organotin and alkyl-lead, expressed as the metal. The results of the analysis of some environmental samples are given.