Occurrence and health risk assessment of pharmaceutically active compounds in riverbank filtrated drinking water

The presence of pharmaceutically active compounds (PhACs) in drinking waters might pose a serious threat to human health worldwide. Therefore, this study sought to measure PhACs in Danube-derived tap water from the Budapest metropolitan region (Hungary), and to compare the results of those measured in the bank filtrate after which a human health risk assessment (based on human risk quotient [hRQ]) was conducted for the detected PhACs. A total of 108 samples were collected from 21 sampling sites throughout 6 sampling campaigns. Our study screened for 102 PhACs, of which 19 were detected in the persistently chlorinated tap water samples. PhAC concentrations were much lower than previously assumed based on the contamination of raw water resources. The total mean concentration of the analyzed PhACs exceeded 30 ng L-1 only at 5 sites. Moreover, the frequency of occurrence (FRO) of the 6 most common compounds (carbamazepine, lamotrigine, lidocaine, benzoylecgonine, tramadol, and cinolazepam) reached 50 % at 4 sites. The most frequent PhAC was carbamazepine (FRO = 53.7 %), the risk level of all PhACs investigated was negligible (hRQ<1) with carbamazepine having the highest hRQs (hRQMAX = 0.007; hRQMEAN = 0.001). Tap water provided lower PhAC concentrations farther from the water abstraction wells and treatment stations along the Danube. The travel time between the drinking water wells and taps with other factors, such as the varying microbiological pattern and the deposits in the supply system influence the PhAC concentrations. Based on the risk assessment, all investigated PhACs pose a negligible risk to consumers in the investigated urban area.