Simultaneous analysis of the antifouling agents: tributyltin, triphenyltin and IRGAROL 1051 in marina water samples

An analytical method for the simultaneous quantitative determination of organotin and triazine antifouling agents in sea water has been developed and optimized. The method involves extraction of organotin compounds and IRGAROL 1051 into dichloromethane with simultaneous derivatization of the organotins using sodium tetraethylborate. The extracts were analyzed without additional purification. Separation and determination of individual compounds, including tributyltin, triphenyltin (together with their degradation products) and IRGAROL 1051 were performed by capillary gas chromatography (cGC). Selected ion monitoring GC-mass spectrometry (GC-MS-SIM) was used to quantify both classes simultaneously, although cGC with flame photometric detection (cGC-FPD) and cGC with nitrogen phosphorus detection (cGC-NPD) were also used separately to analyze the same extract of organotins and triazine, respectively. Recoveries of the individual spiked triazines and the organotin chlorides (at concentrations of approximately 100ng l−1) were higher than 70% (with a RSD lower than ± 13%. The detection limits of the procedure (for 750 ml water samples) range between 0.5 and 1.4 ng 1−1 for the various organotin species and between 0.5 and 2.2 ng 1−1 for IRGAROL 1051 (dependent upon which GC detector is used).