# Assessment of Human Pharmaceuticals in Drinking Water Catchments, Tap and Drinking Fountain Waters
## 3 Results and Discussion
### Occurrence and Comparison with Other Studies
Moreover, a limited amount of publications are available with regard to the occurrence of pharmaceuticals in mineral, drinking and groundwaters worldwide [33]. Besides the aspects previously referred, it is also important to compare our study with the distribution of pharmaceuticals in these water compartments in the different continents, as identified in Figure 1 and Figure S2 (Supplementary Materials), regarding their detection frequencies and median concentrations. The main factors that could impact this data are the pharmaceuticals consumption, the existence and efficacy of wastewater and WTPs, the dilution from wastewater to surface water, soil characteristics and the climate (sunlight and temperature) that can influence pharmaceuticals degradation [7; 19; 21; 23]. Observing the data on the occurrence of pharmaceuticals in these water matrices, as expected, groundwaters presented higher detection frequencies and medians followed by drinking water and mineral water. We can also observe that the European continent is clearly the most studied, whereas for Africa and Asia, there is limited information. Although there are fewer studies regarding the African continent, the detection frequencies were higher (100 and 67%), and their median concentrations (20 and 23 ng L\({}^{-1}\) for CAR and PARA, respectively) similar to those on the European and American continents. This data reflects the lower pharmaceutical consumption but also the lower development of wastewater and WTPs and lower dilution factor of wastewaters due to low precipitation. It is in Europe that higher detection frequencies and median concentrations were observed. Although the development in the wastewater and WTPs and the dilution factor observed in this continent, the observed results are probably related to the higher pharmaceuticals consumption. Antibiotics were the therapeutic group with the higher median concentration (33.8 ng L\({}^{-1}\)), with AZI being the main contributor (median of 89.7 ng L\({}^{-1}\)), followed by NSAIDs, antiepileptics and lipid regulators that presented similar patterns. NSAIDs were found with a detection frequency of 35% and median concentration of 15.1 ng L\({}^{-1}\). It is well known that antiepileptics are among the most frequently found pharmaceutical compounds in drinking and groundwaters (45.3%) and presented median concentration of 13.7 ng L\({}^{-1}\). Concerning the remaining therapeutic groups, the medians were, in decreasing order: SSRIs (1.4 ng L\({}^{-1}\)) and hormones (0.7 ng L\({}^{-1}\)). In America, the median concentrations of the therapeutic groups varied from not detected, for lipid regulators, to 22.7 ng L\({}^{-1}\), for NSAIDs. On the other hand, in Asia, the antibiotics, SSRIs and lipid regulators were evaluated and were not detected. Concerning the median concentrations, antiepileptics (13.6 ng L\({}^{-1}\)) were followed by NSAIDs (6.9 ng L\({}^{-1}\)). In general, pharmaceutical compounds were detected in drinking and groundwaters around the world in trace concentrations, which are in agreement with the results obtained in this study.