Antibiotic-manufacturing sites are hot-spots for the release and spread of antibiotic resistance genes and mobile genetic elements in receiving aquatic environments

• Published in: Environment international Vol. 130; p. 104735
• Main Authors: González-Plaza, Juan José, Blau, Khald, Milaković, Milena, Jurina, Tamara, Smalla, Kornelia, Udiković-Kolić, Nikolina
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier Ltd 01.09.2019; Elsevier
• Subjects: Anti-Bacterial Agents - adverse effects; Anti-Bacterial Agents - pharmacology; Antibiotic pollution; Antibiotic resistance; Bacteria - drug effects; Bacteria - genetics; Drug Industry; Drug Resistance, Microbial - drug effects; Drug Resistance, Microbial - genetics; Genes, Bacterial - genetics; IncP-1; Industrial Waste - adverse effects; Industrial Waste - analysis; Interspersed Repetitive Sequences - genetics; intI1; Manufacturing; Plasmid capture; Rivers - chemistry; IncP-1; Manufacturing; intI1; Plasmid capture; Antibiotic pollution; Antibiotic resistance
• ISSN: 0160-4120; 1873-6750
• DOI: 10.1016/j.envint.2019.04.007

High antibiotic releases from manufacturing facilities have been identified as a risk factor for antibiotic resistance development in bacterial pathogens. However, the role of antibiotic pollution in selection and transferability of antibiotic resistance genes (ARGs) is still limited. In this study, we analyzed effluents from azithromycin-synthesis and veterinary-drug formulation facilities as well as sediments from receiving river and creek taken at the effluent discharge sites, upstream and downstream of discharge. Culturing showed that the effluent discharge significantly increased the proportion of antibiotic resistant bacteria in exposed sediments compared to the upstream ones. Quantitative real-time PCR revealed that effluents from both industries contained high and similar relative abundances of resistance genes [sul1, sul2, qacE/qacEΔ1, tet(A)], class 1 integrons (intI1) and IncP-1 plasmids (korB). Consequently, these genes significantly increased in relative abundances in receiving sediments, with more pronounced effects being observed for river than for creek sediments due to lower background levels of the investigated genes in the river. In addition, effluent discharge considerably increased transfer frequencies of captured ARGs from exposed sediments into Escherichia coli CV601 recipient as shown by biparental mating experiments. Most plasmids exogenously captured from effluent and polluted sediments belonged to the broad host range IncP-1ε plasmid group, conferred multiple antibiotic resistance and harbored class 1 integrons. Discharge of pharmaceutical waste from antibiotic manufacturing sites thus poses a risk for development and dissemination of multi-resistant bacteria, including pathogens. •Effluents are sources of mobile genetic elements associated with resistance genes.•Enrichment of cultivable antibiotic resistant bacteria in polluted sediments•Enrichment of IncP-1 plasmids, class 1 integrons and resistance genes in sediments•Increased transfer of resistance plasmids from sediment bacteria into E. coli•Most plasmids belonged to broad host range IncP-1ε group and confer multiresistance.