Di-and tributyltin species in marine and estuarine waters. Inter-laboratory comparison of two ultratrace analytical methods employing hydride generation and atomic absorption or flame photometric detection

Abstract
Di-and tributyltin compounds present in marine and estuarine waters at sub-parts per billion (<µg l–1) levels were determined using two different chemical speciation procedures. Generally, good analytical agreement was obtained from split samples independently analysed by a simultaneous hydride generation-dichloromethane extraction procedure followed by gas chromatographic separation and flame photometric detection (GC-FPD, performed at the National Bureau of Standards) and by a hydride generation procedure followed by purge and trap collection with boiling-point separation and atomic absorption detection (HG-AA, performed at the Naval Ocean Systems Center). Sea water samples containing tributyltin at sub-p.p.b. levels can be stored frozen (–20 °C) in polycarbonate containers for up to 2–3 months without any serious loss of analyte.