Juan I Sánchez-Avila and Thomas Kretzschmar
In the present work, a sensitive, simple, and fast method with little sample handling has been developed for the determination of 34 semi-volatile organic xenobiotics from rain, sea and ground waters. The method is based on Headspace-Solid Phase Microextraction (HS-SPME) and Gas Chromatography coupled to Mass Spectrometry (GCMS/ MS). Sixteen Polycyclic Aromatic Hydrocarbons (PAHs), eight Phthalate Esters (PEs), six Polychlorinated Biphenyls (PCBs) and two Alkylphenols (APs) were quantitative analyzed in a single run. The best parameters for extraction were determined, including fiber type, sample volume, salinity and extraction time and temperature. In the optimized procedure, 15 ml of water sample was extracted using a 100 μm PDMS fiber in a 20 ml vial and adding 3 g of NaCl (final NaCl concentration of 20%) during 40 min at 80°C (with 10 min of previous equilibration time). A desorption time of 15 min was shown to eliminate carry-over. The method showed good linearity between 0.01 and 10 μgL-1 (r2 from 0.987-0.999). Good precision (63-123%) and accuracy were achieved (1.1-21%). The Methodological Detection Limits (MDL) ranged from 0.00001-0.01364 μg L-1. The method was successfully applied to real samples collected at Ensenada (Mexico). The proposed method represents an effectively and valuable tool for application in environmental water monitoring programs.
Teile diesen Artikel