Analysis of 35 priority semivolatile compounds in water by stir bar sorptive extraction–thermal desorption–gas chromatography–mass spectrometry: Part II: Method validation

A multiresidue method for the determination of 35 organic micropollutants, pesticides, and polycyclic aromatic hydrocarbons (PAHs) in water using stir bar sorptive extraction (SBSE) and thermal desorption coupled to capillary gas chromatography–mass spectrometry (SBSE–TD–GC–MS) has been validated. Method sensitivity, linearity, repeatability and reproducibility, accuracy, matrix effects, and overall uncertainties have been studied for method validation according to the international norm ISO/IEC 17025:1999. The quantification limits ranged from 0.1 to 36 ng/L working in the MS full scan mode. Correlation coefficients of the calibration curves from 20 to 600 ng/L were higher than 0.990 for all the compounds. To validate matrix effects for tap water, ground water and surface water, repeatability, reproducibility, accuracy and overall uncertainty were calculated for the three matrices at 50 and 500 ng/L levels. The accuracy of the method was also evaluated by participating in a proficiency interlaboratory test with real samples.