Distribution of antibiotics along the urban area of the Suquía River (Córdoba, Argentina).

SANTOS, LUCÍA HELENA; WUNDERLIN D.A.; AMÉ, M.V.; RODRIGUEZ CASTRO, CAROLINA; BARCELÓ D; VALDÉS M.E.; GIORGI, ADONIS; RODRIGUEZ-MOZAZ, S

Cartagena

Congreso; SETAC Latin America 13th Biennial Meeting; 2019

Sociedad de Toxicología y Química Ambiental (SETAC)

Antibiotics are a particular group of emerging contaminants that have gained a lot of attention because of its high consumption in human and veterinary medicine and itsrecently found distribution in the environment. Surface waters receive trace amounts of antibiotic residues through runoff and effluents of wastewater treatment plants being the spread of antibiotic resistance genes one of the main worldwide concerns. The aim of this study was to evaluate the presence and environmental distribution of human antibiotics in the area of urban influence of the Suquía River (Córdoba city-1,330,023 inhabitants,Argentina). For this purpose, samples of water, sediment and natural river biofilms were collectedat five sampling points receiving different sources of urban pollution: S1- control (upstream Córdoba city and the intake of water supply), S2 (dump area), S3 (downstream a city ringway), S4 and S5 (6 and 10 km downstream the city WWTP effluent discharge). Samples were taken in 2 monitoring campaigns, to consider seasonal variations in the river flow (dry and wet seasons, 2016). Water samples were filtered through 0.45 μm and extracted by solid phase extraction (SPE). Sediment samples were extracted by pressurized liquid extraction and biofilm samples were extracted by bead-disruption. Both solid matrixes were purified by SPE. Fifty antibiotic residues, covering ten chemical groups and some of their metabolites, were determined by UPLC-ESI(QqLIT)MS/MS analysis. Twelve antibiotics belonging to 8 chemical families were detected in samples of urban influence (S2 to S5), during wet and dry seasons. No antibiotics were detected in S1. Both sites downstream the WWTP were the most polluted sites (highest loads and variety of antibiotics). However, there are non-point sources of antibiotic pollution in S2 and S3. Trimethoprim, fluoroquinolones and macrolides were detected in the 3 compartments. While metronidazole, cephalexin and clindamycin were only detected in water, doxicyciln and sulfatiazol in sediments and cinoxacin in biofilm. The highest concentrations were detected in wet season, compared to the dry one, which shows differences in human consumption, environment persistence and accumulation of antibiotics.