Occurrence of pharmaceuticals in the wastewater of a Greek hospital:Combining consumption data collection and LC-QTOF-MS analysis br

In this article we applied drug consumption approach and chemical analysis in parallel to investigate the concentra-tions of a large number of pharmaceuticals in different streams of a General Hospital. Drugs consumption data was col-lected during two periods (Period 1, 2) and the predicted environmental concentrations (PECs) were estimated for thewastewater of a building housing specific medical services (Point A) and for the entire hospital (Point B). Hospitalwastewater samples (HWW) samples were also collected from these points and periods and the measured environmen-tal concentrations (MEC) were determined using UHPLC-ESI-QTOF-MS/MS. According to consumption data, thehighest number of drugs was consumed in the departments of Hematology, Intensive Care Unit, Cardiology, InternalMedicine, and Oncology, while the number of active substances used in the hospital was 413 (Period 1) and 362 (Pe-riod 2). For most substances, much higher PEC and MEC values were found at the HWW of Point A indicating that on-site treatment of this stream could be examined in the future. The application of wide-scope target analysis allowed thequantification of 122 compounds, while 21 additional substances were identified using suspect screening. The highestmean concentrations in Period 1 were found for acetaminophen (1100 mu g/L) and rifaximin (723 mu g/L), while in Period2 for iopromide (458 mu g/L) and acyclovir (408 mu g/L). Among the detected compounds, 19 metabolites were deter-mined. Atenolol acid, 1-hydroxy-midazolam and clopidogrel carboxylic acid were quantified at concentrationsmuch higher than parent compounds indicating the importance of metabolites' monitoring in HWW. Calculation ofPEC/MEC ratio for 36 pharmaceuticals showed sufficient correlation of these values for 19 % to 33 % of the substancdepending on the examined period and sampling point. The parallel collection of drugs consumption data and chem-ical analysis give a thorough picture of the substances present in HWW and their main sources, facilitating decision-making for their better management.