title: A one-year follow-up analysis of antidepressants in Portuguese wastewaters: occurrence and fate, seasonal influence, and risk assessment.
abstract: The occurrence, fate, seasonal influence and environmental risk assessment of four selective serotonin re-uptake inhibitors (SSRIs) antidepressants, citalopram, fluoxetine, paroxetine and sertraline, were studied in 15 different wastewater treatment plants (WWTPs) across Portugal. Influent and effluent samples from four sampling campaigns, in 2013, were extracted through Oasis HLB cartridges, and quantified through liquid chromatography with tandem mass spectrometry (LC-MSn).Results showed that citalopram was the SSRI most frequently found, both in influents and in effluents, with mean mass loads ranging between 14.56 and 9.51 mg/day/1000 inhabitants, respectively. Fluoxetine and sertraline were only detected in influent samples, in lower mean mass loads (14.60 and 1.36 mg/day/1000 inhab., respectively), whereas paroxetine was found in influent and effluent samples (12.61 and 18.90 mg/day/1000 inhab., respectively). WWTPs were not capable of completely removing these pharmaceuticals; nonetheless, the mean removal efficiency was 82.24%. Removal efficiency was lower in winter (74.21%), summer (72.02%), and autumn (81.19%), when compared to spring (100%). Our results translate the variations in SSRI prescription and use between the five Portuguese regions in study. Influent contaminated samples were found in WWTPs from Lisbon, Alentejo, Center and North (28.25, 19.01, 16.55 and 6.98 mg/day/1000 inhab., respectively). In the Algarve region no contaminated samples were found. A seasonal pattern in the presence of SSRIs in influent wastewaters was observed. The SSRIs mass loads in influent wastewaters were higher in autumn, followed by spring, winter, and summer. Finally, the potential ecotoxicological risk posed by SSRIs to different trophic levels of aquatic organisms, exposed to the effluent wastewaters studied was evaluated by means of risk quotients (RQ). Citalopram and paroxetine, the only SSRIs found in these samples, presented RQ lower than 1. According to the results, algae appeared to be the most sensitive followed by fish and daphnids.
authors.affiliation: Group of Health Surveillance, Center of Pharmaceutical Studies, Faculty of Pharmacy, University of Coimbra, Polo III, Azinhaga de Sta Comba, 3000-548 Coimbra, Portugal. Electronic address: ljgsilva@hotmail.com.
authors.forename: Liliana J G
authors.initials: LJ
authors.lastname: Silva
authors.affiliation: Group of Health Surveillance, Center of Pharmaceutical Studies, Faculty of Pharmacy, University of Coimbra, Polo III, Azinhaga de Sta Comba, 3000-548 Coimbra, Portugal. Electronic address: amptpereira@gmail.com.
authors.forename: André M P T
authors.initials: AM
authors.lastname: Pereira
authors.affiliation: INFARMED, I.P.-National Authority of Medicines and Health Products, 1749-004 Lisboa, Portugal; Department of Pharmacology, Faculty of Pharmacy, University of Lisbon, Av. Prof. Gama Pinto, 1649-003 Lisboa, Portugal. Electronic address: leonor.meisel@infarmed.pt.
authors.forename: Leonor M
authors.initials: LM
authors.lastname: Meisel
authors.affiliation: Group of Health Surveillance, Center of Pharmaceutical Studies, Faculty of Pharmacy, University of Coimbra, Polo III, Azinhaga de Sta Comba, 3000-548 Coimbra, Portugal. Electronic address: cmlino@ff.uc.pt.
authors.forename: Celeste M
authors.initials: CM
authors.lastname: Lino
authors.affiliation: Group of Health Surveillance, Center of Pharmaceutical Studies, Faculty of Pharmacy, University of Coimbra, Polo III, Azinhaga de Sta Comba, 3000-548 Coimbra, Portugal. Electronic address: apena@ff.uc.pt.
authors.forename: Angelina
authors.initials: A
authors.lastname: Pena
mesh_terms: D000928:Antidepressive Agents / Q000032:analysis*; D004784:Environmental Monitoring; D005500:Follow-Up Studies; D011174:Portugal; D018570:Risk Assessment; D012621:Seasons; D014865:Waste Disposal, Fluid / Q000706:statistics & numerical data; D062065:Wastewater / Q000737:chemistry* / Q000706:statistics & numerical data; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D000928:Antidepressive Agents; D062065:Wastewater; D014874:Water Pollutants, Chemical
keywords: Environmental contaminants; Environmental risk; Municipal wastewaters; Occurrence and fate; Seasonal influence; Selective serotonin re-uptake inhibitors