Speciation analysis of organotin compounds in the Maltese marine environment

Abstract

Organotin speciation analysis is described for the Maltese marine environment. An analytical method was used involving extraction from the environmental matrix (seawater, sediment and surface microlayer) followed by propylation and capillary gas chromatography using flame photometric detection. The method was systematically checked and its limitations identified. Concentration levels for the commonly occurring organotin species tributyltin (TBT) and its debutylated metabolites, including inorganic tin (IV), were determined, together with those of less frequently reported methyl and phenyltin species. The highest concentration of TBT, the most toxic of butyltin species, was 0.3 ugSn L-1 in harbour waters, but was below detection limits (5 ngSn L-1) in open sea, 1.6 km offshore.