Abundance of antibiotics, antibiotic resistance genes and bacterial community composition in wastewater effluents from different Romanian hospitals. (June 2017)

• Record Type: Journal Article
• Authors: Szekeres, Edina; Baricz, Andreea; Chiriac, Cecilia Maria; Farkas, Anca; Opris, Ocsana; Soran, Maria-Loredana; Andrei, Adrian-Stefan; Rudi, Knut; Balcázar, Jose Luis; Dragos, Nicolae; Coman, Cristian
• Is Part Of: Environmental pollution. Volume 225(2017)
• Page Start: 304
• Page End: 315
• Publication Date: 2017-06
• Subjects: Antibiotics -- Antibiotic resistance genes -- Bacterial community composition -- Hospital wastewater -- Romania; Pollution -- Periodicals; Pollution -- Environmental aspects -- Periodicals; Environmental Pollution -- Periodicals; Pollution -- Périodiques; Pollution -- Aspect de l'environnement -- Périodiques; Pollution -- Effets physiologiques -- Périodiques; Pollution; Pollution -- Environmental aspects; Periodicals; Electronic journals; 363.73
• DOI: 10.1016/j.envpol.2017.01.054
• Languages: English
• ISSNs: 0269-7491

Abstract

Abstract: Antimicrobial resistance represents a growing and significant public health threat, which requires a global response to develop effective strategies and mitigate the emergence and spread of this phenomenon in clinical and environmental settings. We investigated, therefore, the occurrence and abundance of several antibiotics and antibiotic resistance genes (ARGs), as well as bacterial community composition in wastewater effluents from different hospitals located in the Cluj County, Romania. Antibiotic concentrations ranged between 3.67 and 53.05 μg L −1, and the most abundant antibiotic classes were β-lactams, glycopeptides, and trimethoprim. Among the ARGs detected, 14 genes confer resistance to β-lactams, aminoglycosides, chloramphenicol, macrolide-lincosamide-streptogramin B (MLSB) antibiotics, sulfonamides, and tetracyclines. Genes encoding quaternary ammonium resistance and a transposon-related element were also detected. The sul I and qac EΔ1 genes, which confer resistance to sulfonamides and quaternary ammonium, had the highest relative abundance with values ranging from 5.33 × 10 −2 to 1.94 × 10 −1 and 1.94 × 10 −2 to 4.89 × 10 −2 copies/16 rRNA gene copies, respectively. The dominant phyla detected in the hospital wastewater samples were Proteobacteria, Bacteroidetes, Firmicutes, and Actinobacteria . Among selected hospitals, one of them applied an activated sludge and chlorine disinfection process before releasing the effluent to the municipal collector. This conventional wastewater treatment showed moderate removal efficiency of the studied pollutants, with a 55–81% decrease in antibiotic concentrations, 1–3 order of magnitude lower relative abundance of ARGs, but with a slight increase of some potentially pathogenic bacteria. Given this, hospital wastewaters (raw or treated) may contribute to the spread of these emerging pollutants in the receiving environments. To the best of our knowledge, this study quantified for the first time the abundance of antibiotics and ARGs in wastewater effluents from different Romanian hospitals. Graphical abstract: Highlights: Antibiotic, ARGs abundance and inhabiting microbiota were investigated in hospital wastewaters. High concentrations of β-lactam antibiotics, glycopeptides and trimethoprim were detected. The sul I and qac EΔ1 resistance genes had the highest relative abundance in samples. Proteobacteria, Bacteroidetes, Firmicutes, and Actinobacteria were identified as dominant phyla. Conventional wastewater treatment showed a moderate removal efficiency of studied pollutants.