| Abstract: | A solid-phase extraction method, using a phenyl-bonded silica sorbent, was developed for the isolation of mono- and di-methyltin, -butyltin and -octyltin from drinking water. Recoveries averaged 92% over two tested sample weights and spiking levels. Ethyl derivatives were made by Grignard reaction for determination by gas chromatography–atomic absorption spectrometry (GC–AAS). Static and repetitive extraction studies were conducted at 24 and 65°C. Butyltins rapidly leached into drinking water kept in chlorinated poly(vinyl chloride) (CVPC) pipe samples. Monobutyltin and dibutyltin levels reached 19.8 (13.4 as Sn) and 197 (100.4 as Sn) ng g?1 respectively in water samples collected from CPVC pipe heated to 65°C. Butyltins were still leached from CPVC pipe after 20 repetitive extractions, suggesting that new CPVC water systems would contaminate water with organotins for some time after installation. © 1997 John Wiley & Sons, Ltd. |
