Simultaneous solid phase extraction coupled with liquid chromatography tandem mass spectrometry and gas chromatography tandem mass spectrometry for the highly sensitive determination of 15 endocrine disrupting chemicals in seafood

This study aimed to develop a sensitive and reliable multi-residue method for the determination of trace amounts of endocrine disrupting chemicals including five phthalate esters (PAEs), five monoalky phthalate esters (MPEs), four alkylphenols (APs) and bisphenol A (BPA) in seafood. Ultrasonic liquid extraction was selected for extraction based on acetonitrile, instead of frequently-used n-hexane, due to its lower background of PAEs. Application of solid phase extraction (SPE) with primary secondary amine (PSA, 1 g/6 mL) cartridge achieved the relatively low matrix effects for MPEs and BPA in seafood. To our knowledge, it is the first study reporting about simultaneous extraction and purification of PAEs, MPEs, APs and BPA in biota samples. To obtain the maximum sensitivity, both liquid chromatography tandem mass spectrometry (LC–MS/MS) and gas chromatography tandem mass spectrometry (GC–MS/MS) were applied for analysis. This method was validated and tested on fish, mollusk and prawn. Sufficient linearity was verified by Mandel's fitting test for the matrix-matched calibrations used in this study for MPEs, APs and BPA, between 0.5 ng/g and 200 ng/g or 400 ng/g. And correlation coefficients of all calibrations suppressed 0.99 for all analytes. Good recoveries were obtained, ranging from 60% to 127% for most compounds. The sensitivity was good with method detection limits (MDLs) of 0.015–2.2 ng/g wet weight (ww) for all compounds. Most MDLs are much lower than those in previous reports. The sensitive method was then applied on real fish, mollusk and prawn samples from the Yangtze River Delta sea area (China), and all the target compounds were detected with the maximum concentrations of PAEs, MPEs, APs and BPA up to 219.3 ng/g ww, 51.4 ng/g ww, 62.0 ng/g ww and 8.6 ng/g ww, respectively.