Presence of antibiotics in the Suquía river (Córdoba, Argentina).

BARCELÓ, DAMIÁ; RODRIGUEZ MOZAZ, S.; VALDES, MARIA EUGENIA; AMÉ, MARÍA VALERIA; SANTOS, L.H.M.L.M.

Pretoria

Workshop; Africa Food Safety Workshop 2018; 2018

International Atomic Energy Agency, National Metrology Institute of South Africa

Pharmaceutically active compounds (PhACs) have gained a lot of attention in the last decades, since they are widely distributed in the environment and may cause adverse effects to biota and human health. Antibiotics are particularly relevant PhACs, because of their high consumption in human and veterinary medicine and their potential to cause resistance amongst natural bacterial populations. In this study, we evaluated the presence of antibiotics in a river receiving different sources of urban pollution. For this purpose, we collected samples of water and natural river biofilms at five sampling points selected in the Suquía river, along the area of urban anthropogenic pollution of Cordoba city (1,330,023 inhabitants): 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 SPE. Biofilms samples were freeze-dried and extracted by bed-disruption, followed 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 eight chemical families were detected in water and biofilm samples, in the four sites (S2-S5) receiving the city discharges. Cefalexin (family of cephalosporins) and clarithromycin (macrolide) were the most frequent antibiotics in water samples while the fluoroquinolones ofloxacin and ciprofloxacin and the macrolides azithromycin and clarithromycin were the most frequent antibiotics in biofilm (S2,S3,S4 and S5 during both seasons). Sampling sites downstream the WWTP discharge were the most polluted sites with the highest loads and variety of antibiotics. Different antibiotic pattern was found in wet and dry season, which could be related to human antibiotic consumption.