Simultaneous determination of PAHS, nitro-PAHS and quinones in surface and groundwater samples using SDME/GC-MS

Environmental contamination by PAHs and their derivatives can cause damage to human health due to the carcinogenic and mutagenic potential of these compounds. This work proposes a new method for simultaneous determination of PAHs, nitro-PAHs and quinones in surface and groundwater samples employing gas chromatography coupled to mass spectrometry (GC-MS) after single-drop microextraction (SDME). The extraction step using SDME was optimized and it was found that the best experimental conditions for 10 mL samples are: drop volume of 1.0 μL, toluene as extraction solvent, and stirring time of 30 min at 200 rpm. The limits of detection obtained were from 0.01 to 0.03 μg L− 1 for PAHs, from 0.26 to 1.07 μg L− 1 for nitro-PAHs and from 6.96 to 468 μg L− 1 for quinones. The limits of quantification obtained were from 0.05 to 0.09 μg L− 1 for PAHs, from 1.24 to 4.31 μg L− 1 for nitro-PAHs and from 23.2 to 1559 μg L− 1 for quinones. For intraday precision, the maximum value obtained for RSD was 19% and for interday precision was 18.7%. The accuracy was verified using addition/recovery tests and the recoveries achieved varied from 36% to 152% for PAHs, from 23% to 103% for nitro-PAHs and from 48% to 134% for quinones. Eight PAHs, six nitro-PAHs and two quinones were detected and quantified in surface and groundwater samples. The average concentrations obtained were 0.70 μg L− 1 (naphthalene) for PAHs, 1605 μg L− 1 (1,2-naphthoquinone) for quinones and 5.61 μg L− 1 (1-nitropyrene) for nitro-PAHs. Indeed, the proposed method showed good sensitivity, linearity, precision and accuracy for the determination of PAHs, nitro-PAHs and quinones in water samples.