Systematic assessment of extraction of pharmaceuticals and personal care products in water and sediment followed by liquid chromatography-tandem mass spectrometry.

Two solid-phase extraction methods were systematically studied to determine 32 pharmaceuticals and personal care products in water and sediments by ultrahigh-performance liquid chromatography-tandem mass spectrometry. One involves HLB cartridges activated with sodium dodecyl sulfate before the passage of the sample to form an ion pair with cationic analytes, and the other uses mixed HLB-cation exchange cartridges. The accuracy of the sodium dodecyl sulfate method was good for most compounds (recoveries of 61-120% with relative standard deviation less than 23%). However, the recoveries for atorvastatin, codeine, paracetamol, flufenamic acid, and salicylic acid were approximately 50% and for omeprazole and triclocarban were even lower (from 0 to 12%). The detection limits were 1.65-25 ng L-1 in water and 0.33-4.00 ng g-1 (dry weight) in sediment. The recoveries for the mixed-mode cartridge (Strata-X-CW) method ranged from 57% to 120% with relative standard deviation less than 21%, with the exception of codeine [25% (water)], metformin [11% (sediment)], paracetamol [48% (sediment)], and salicylic acid [32% (sediment)]. The detection limits were 1.65-38.35 ng L-1 in water and 0.33-10 ng g-1 (dry weight) in sediment. Both methods followed the same pattern when applied to water. For sediments, the recoveries, which offer good performance, were not very high, although 60% of the compounds had recoveries greater 80%. The methods were applied to the analysis of surface water and sediments from the Albufera Natural Park (Spain). Twenty-seven of 32 analytes were detected in the samples analyzed.