Input of pharmaceuticals through coastal surface watercourses into a Mediterranean lagoon (Mar Menor, SE Spain): Sources and seasonal variations R. Moreno-González a , S. Rodríguez-Mozaz b , M. Gros b , E. Pérez-Cánovas a , D. Barceló b,c , V.M. León a, ⁎ a Instituto Español de Oceanografía, Centro Oceanográfico de Murcia, Apdo. 22, C/ Varadero 1, San Pedro del Pinatar, 30740 Murcia, Spain b Catalan Institute for Water Research (ICRA), Parc Científic i Tecnològic de la Universitat de Girona, Edifici H 2 O. Emili Grahit, 101-17003 Girona, Spain c Department of Environmental Chemistry, IDAEA-CSIC, C/Jordi Girona 18-26, 08034 Barcelona, Spain HIGHLIGHTS • 56 pharmaceuticals were detected in surface waters • The major pharmaceuticals source was effluent from the Los Alcázares WWTP • Antibiotics, psychiatric drugs and anti- hypertensives were the most persistent • Macrolides and b-blockers showed sea- sonal variations • 11 kg year-1 of pharmaceuticals accessed the Mar Menor through El Albujón water- course GRAPHICAL ABSTRACT abstract article info Article history: Received 15 February 2014 Received in revised form 11 April 2014 Accepted 22 April 2014 Available online xxxx Editor: Adrian Covaci Keywords: Pharmaceuticals Coastal watercourse Mar Menor lagoon Seasonal input Surface water The seasonal occurrence and distribution of 69 pharmaceuticals along coastal watercourses during 6 sampling campaigns and their input through El Albujón watercourse to the Mar Menor lagoon were determined by UPLC–MS-MS, considering a total of 115 water samples. The major source of pharmaceuticals running into this watercourse was an effluent from the Los Alcazares WWTP, although other sources were also present (runoffs, excess water from irrigation, etc.). In this urban and agriculturally influenced watercourse different pharmaceu- tical distribution profiles were detected according to their attenuation, which depended on physicochemical water conditions, pollutant input variation, biodegradation and photodegradation rates of pollutants, etc. The less recalcitrant compounds in this study (macrolides, β-blockers, etc.) showed a relevant seasonal variability as a consequence of dissipation processes (degradation, sorption, etc.). Attenuation was lower, however, for diclofenac, carbamazepine, lorazepam, valsartan, sulfamethoxazole among others, due to their known lower degradability and sorption onto particulate matter, according to previous studies. The maximum concentrations detected were higher than 1000 ng L -1 for azithromycin, clarithromycin, valsartan, acetaminophen and ibuprofen. These high concentration levels were favored by the limited dilution in this low flow system, and consequently some of them could pose an acute risk to the biota of this watercourse. Considering data from 2009 to 2010, it has been estimated that a total of 11.3 kg of pharmaceuticals access the Mar Menor lagoon annually through the El Albujón Science of the Total Environment 490 (2014) 59–72 ⁎ Corresponding author. Tel.: +34 968179410; fax: +34 968184441. E-mail address: victor.leon@mu.ieo.es (V.M. León). http://dx.doi.org/10.1016/j.scitotenv.2014.04.097 0048-9697/© 2014 Elsevier B.V. All rights reserved. Contents lists available at ScienceDirect Science of the Total Environment journal homepage: www.elsevier.com/locate/scitotenv