Combining an effect-based methodology with chemical analysis for antibiotics determination in wastewater and receiving freshwater and marine environment

Two different methodologies were combined to evaluate the risks that antibiotics can pose in environment; i) an effect-based methodology based on microbial growth inhibition and ii) analytical method liquid-chromatography coupled mass spectrometry (LC-MS). The first approach was adapted validated for screening of four antibiotic families, specifically macrolides/β-lactams, quinolones, sulfonamides tetracyclines. LC-MS applied identification quantification target antibiotics; then, obtained results with ecotoxicological data from literature determine environmental risk. two used analysis water samples (wastewater, river seawater) biofluids (fish plasma mollusk hemolymph) monitoring campaigns undertaken Ebro Delta Mar Menor Lagoon (both Mediterranean coast Spain). Both approaches highlighted macrolides (azithromycin) quinolones (ciprofloxacin ofloxacin) as main wastewater treatment plant (WWTP) effluents potential risk environment. However, no aquatic life identified river, lagoon seawater levels much lower than those WWTP effluents. Fish River organisms presenting highest concentration when compared bivalves (mussels) Sea gastropods (marine snails) Lagoon. successfully determined wastewater, but its applicability less clear waters such seawater, due high detection limits. Improving sample preconcentration could increase sensibility. Overall, combination both provides comprehensive insights occurrence associated areas under study.