Combining passive sampling and tandem mass spectrometry for the determination of pharmaceuticals and other emerging pollutants in drinking water

After calibration, samplers were deployed in the inlet and the outlet of two drinking water treatment plants in Northwestern Italy, for two and four weeks; the extracts were then analyzed by means of LC-MS/MS in multiple reaction monitoring mode, which provided high sensitivity and allowed the detection of the selected compounds at the low ng L− 1 level. Three analytes were measured in both treatment plants: the two perfluorinated compounds, in the range 2.93-13.42 ng L− 1, and caffeine, in the range 0.07-0.93 ng L− 1.