Applicability of microwave-assisted extraction combined with LC–MS/MS in the evaluation of booster biocide levels in harbour sediments

A new sample treatment method for the determination of four common booster biocides (Diuron, TCMTB, Irgarol 1051 and Dichlofluanid) in harbour sediment samples has been developed that uses liquid chromatography–tandem mass spectrometry (LC–MS/MS) after microwave-assisted extraction, followed by clean-up and a solid phase extraction preconcentration step (MAE–SPE). The effects of different variables on MAE–SPE were studied. The recoveries obtained were greater than 75%, and the relative standard deviation was less than 7%. The detection limits ranged between 0.1 and 0.3 ng g−1. The developed methodology was successfully applied to the evaluation of the presence of booster biocides in sediment samples from different harbours and marinas of Gran Canaria Island (Canary Islands, Spain).