# Assessment of Human Pharmaceuticals in Drinking Water Catchments, Tap and Drinking Fountain Waters
###### Abstract  
The occurrence of pharmaceuticals in water catchments and drinking waters raises potential risks to public health. Therefore, after addressing the major aquatic contamination pathway, the wastewater treatment plants (WWTPs), and, subsequently, surface waters, 18 human pharmaceuticals from 6 therapeutic groups (antibiotics, lipid regulators, selective serotonin reuptake inhibitors, non-steroidal anti-inflammatory drugs (NSAIDs) and hormones) were analyzed in drinking water catchments, tap and drinking fountain waters. This was performed by solid phase extraction (SPE) and liquid chromatography coupled with tandem mass detection (LC-MS/MS). The 97 samples analyzed were collected from 31 different sites in the center of Portugal. All samples presented concentrations below the method detection limits (MDLs) that ranged between 1.13 to 5.45 ng L\({}^{-1}\). The achieved results contributed to a better knowledge on the Portuguese and European context of drinking water, since there is a knowledge gap regarding this matrix. Comparing our data with other studies, published worldwide, we can observe that median concentrations of pharmaceuticals were reported in the low ng L\({}^{-1}\) levels, values close to our MDLs. Consequently, it is unlikely that, in light of the current knowledge, the presence of pharmaceuticals in drinking water presents a threat to human health. environmental contaminants; pharmaceuticals; chemicals; Portugal; occurrence and fate +
Footnote †: journal: Medical  
in surface waters [8]. Therefore, it is important to evaluate not only drinking waters but also its catchments in order to evaluate the removal of pharmaceuticals in water treatment plants (WTPs) [9]. Due to cumulative and multigenerational exposure, the environmental impact of pharmaceuticals and the potential for negative ecotoxicological effects on the aquatic environment, even at sublethal concentrations, has been recognized worldwide. Once released into the environment, they can remain bioactive and pose a toxicological risk to non-target organisms as well as for human health [10; 11]. The main risks associated with their presence in the aquatic environment is not only acute toxicity but also their genotoxicity, emergence of bacterial resistant genes, and endocrine disruption [12; 13]. Examples of ecotoxicological effects are the Gyps vulture population decline in India after consumption of contaminated carcasses with diclofenac and the feminization in male fish in rivers due to the presence of estrogens [14]. Additionally, as referred, antibiotic presence in the aquatic environment increases the selective pressure promoting the emergence and/or dissemination of bacteria resistant genes, one of the major public health concerns [13]. Additionally, the occurrence of several pharmaceuticals, together with the array of other contaminants present in the water compartment increases the complexity of these matrices' toxicity, promoting non-additive interactions that can lead to unexpected toxic effects [12]. Despite the risk evidence, legal limits have not yet been established in drinking water and therefore, routine monitoring programs have not yet been implemented, as is the case for the evaluation of regulated chemical and microbial parameters [15]. The pharmaceuticals in study, key representatives of the major therapeutic groups, were selected based on their high consumption in Portugal, legislation, previous data on their occurrence in water bodies, their attenuation/persistence in surface waters as well as considering the relative concern about their potential toxicological impact [16; 17; 18; 19; 20]. This study aims to provide a clearer view of pharmaceutical contamination in drinking water catchments (surface and groundwaters), in tap and drinking fountains in the center of Portugal.