Gas chromatography—mass spectrometry determination of triclosans in water, sediment and fish samples via methylation with diazomethane

Traces of 2,4,4ʹ-trichloro-2ʹ-hydroxydiphenyl ether (triclosan) and its 3-chlorinated derivatives in environmental samples were determined by capillary GC-MS with selected ion monitoring via methylation with diazomethane involving liquid-liquid extraction and other clean up procedures. In fish samples, interference from methyl ester type biota components could be successfully eliminated by performing their saponification after methylation. The triclosans could be determined in water in the range 0.05–0.15 ng/ml with relative standard deviations (RSDs) of 3.0%–17.4%. The detection limits of the triclosans in water, sediment and fish samples were 0.030–0.059 ng/ml, 1.7–4.6 and 0.89–2.5 ng/g, respectively. Their recoveries from river water, sea water, sediment and fish samples were 74%–112%, 91%–119%, 83%–117% and 85%–119% with RSDs 3.1%–11.7%, 3.9%–9.3%, 5.5%–12.6% and 3.3%–6.9%, respectively.