Concentration of pharmaceutical compounds in greywater at different steps of an house-scale vertical green wall treatment

The results of the greywater treatment throughout a vertical wall are depicted in the table. Samples from the inlet, the outlet of the green wall, and the outlet from the ozonization treatment were collected weekly for 3 weeks. Water samples were extracted and preconditioned by SPE, and the final extracts were analyzed by LC-MS/MS with a SCIEX QTRAP 5500 to determine the presence of 56 compounds, mostly pharmaceuticals and the stimulant, caffeine. The method performance was evaluated with recovery (spiked) samples, and the method detection and quantification limits (MDL and MQL, respectively). For compounds with acceptable results (recoveries between 40-150%), the concentrations were reported (in ng/L). Columns are grouped according to the step of the treatment, and on each of them, the 3 sampling dates (a sample per day) are depicted.