Development and Validation of an LC-ESI-MS/MS Method for the Determination of Six Selected Contaminants of Emerging Concern in Surface Water from Brandywine Creek, USA

A sensitive LC-ESI-MS/MS (Liquid chromatography–Electrospray Ionization-Tandem Mass Spectrometry) method was developed and validated for the simultaneous determination of six selected contaminants of emerging concern in surface water from Brandywine Creek, USA. Sample preparation was based on solid-phase extraction using OASIS HLB cartridges, followed by chromatographic separation on a Poroshell EC-C18 column and tandem mass spectrometric detection using a Jet Spray electrospray ionization source operated in positive ion multiple reaction monitoring (MRM) mode. The total chromatographic run time was 15 min. The method was validated over analyte-specific calibration ranges of 2.0 to 100 ng/mL for acetaminophen, codeine, sulfamethoxazole, fluoxetine, thiabendazole, and of 0.7 to 75 ng/mL for chlorpyrifos. Extraction recoveries ranged from 81.2% to 96.3%. The validated method showed satisfactory sensitivity for reliable trace-level determination and was successfully applied to the analysis of ten Brandywine Creek surface-water samples. The proposed method provides a suitable analytical approach with potential application to the monitoring of chemically diverse contaminants of emerging concern in tributary surface waters.