Optimization of a Modified QuEChERS Method for Multiresidue Analysis of Pharmaceuticals and Personal Care Products in Sewage and Surface Water by LC-MS/MS.

A quick, sensitive multiresidue method was developed for the analysis of 19 multiclass pharmaceuticals and personal care products (PPCPs) in surface water and sewage water. The proposed modified QuEChERS method involved the extraction of water samples (10 mL) with acetonitrile (10 mL) after the addition of 1% acetic acid, 4 g magnesium sulfate, and 0.2 g ammonium acetate, and was validated in distilled water, surface water, and sewage water with respect to linearity, LOD and LOQ, precision, and accuracy. The LOD and LOQ varied within the ranges of 0.001-0.167 and 0.002-0.25 ng/mL, respectively. Recoveries of the target compounds ranged from 73 to 125%, with precision RSD values < 27%. The method provided a precise estimation of PPCPs in field samples, and acetaminophen, atenolol, metformin, sulfamethoxazole, carbamazepine, methylparaben, and triclosan were detected in concentrations ranging from 0.10 to 1.40 and 0.10 to 3.4 ng/mL in surface water and sewage water, respectively. This is an innovative application of the QuEChERS approach for estimation of PPCPs from aqueous matrixes. The method provides significantly higher output (preparation of 25-30 samples a day) compared to conventional SPE-based methods (< 10 samples a day).