Identification and quantification of 81 pharmaceutical compounds in a surface flow treatment wetland: Differentiated retention in water-soil-plants
The occurrence of pharmaceutical compounds (PHc) in the aquatic environment is due to the incomplete micropollutant removal efficiencies of Wastewater Treatment Plants (WWTPs). As a consequence, some PHc in rivers are known to be responsible for the feminization of male fishes resulting from exposure to waterborne hormones, even at concentrations of a few ng∙L‐1. This study involved the monitoring of PHc removal efficiencies in a WWTP located in Haut-Rhin, France, over the course of one year. The WWTP is composed of vertical flow constructed wetlands (VFCWs) followed by a surface flow treatment wetland (SFTW). The VFCW is sized to treat 808 people equivalents. Water, plants and soil from the VFCW and SFTW were sampled every two months and 81 PHc were investigated. Initial results show an increase in the number of PHc during winter campaigns, with maximum concentrations reached in November 2016 by amitriptyline (antidepressant) at 2.9 μg∙L-1. During the summer, ethinylestradiol (hormone) was the highest PHc concentration detected at 54 μg∙L‐1 in wastewater. VFCW removal efficiencies of PHc ranged from 30% to 70% and were completed by SFTW removal efficiencies (30-70%). Concerning plant and soil samples from the SFTW, PHc concentrations were detected at pg∙g‐1 levels (10‐12 g∙g‐1 of dried plants or sludge). These results illustrate the PHc cumulative abilities of plants and soil. Moreover, the presence and concentrations of PHc compounds depend on plant type, which suggests a specific relationship between PHc compounds and plant species.