0
Article ? AI-assigned paper type based on the abstract. Classification may not be perfect — flag errors using the feedback button. Tier 2 ? Original research — experimental, observational, or case-control study. Direct primary evidence. Environmental Sources Sign in to save

Microplastics accumulate priority antibiotic-resistant pathogens: Evidence from the riverine plastisphere

Environmental Pollution 2023 58 citations ? Citation count from OpenAlex, updated daily. May differ slightly from the publisher's own count. Score: 60 ? 0–100 AI score estimating relevance to the microplastics field. Papers below 30 are filtered from public browse.
Isabel Silva, Elsa T. Rodrigues, Marta Tacão, Isabel Henriques

Summary

Researchers placed microplastics in river water and found they accumulated more antibiotic-resistant bacteria than natural sand particles, including dangerous pathogens like E. coli and Klebsiella. Most of the bacteria isolated from the plastic surfaces were multi-drug resistant and carried virulence traits like biofilm formation. This suggests microplastics in waterways may act as rafts for spreading antibiotic resistance through the environment.

Study Type Environmental

Microplastics (MPs) might accumulate and transport antibiotic-resistant bacteria (ARB) in aquatic systems. We determined the abundance and diversity of culturable ciprofloxacin- and cefotaxime-resistant bacteria in biofilms covering MPs placed in river water, and characterized priority pathogens from these biofilms. Our results showed that the abundance of ARB colonizing MPs tends to be higher compared to sand particles. Also, higher numbers were cultivated from a mixture of polypropylene (PP), polyethylene (PE) and polyethylene terephthalate (PET), compared to PP and PET alone. Aeromonas and Pseudomonas isolates were the most frequently retrieved from MPs placed before a WWTP discharge while Enterobacteriaceae dominated the culturable plastisphere 200 m after the WWTP discharge. Ciprofloxacin- and/or cefotaxime-resistant Enterobacteriaceae (n = 54 unique isolates) were identified as Escherichia coli (n = 37), Klebsiella pneumoniae (n = 3), Citrobacter spp. (n = 9), Enterobacter spp. (n = 4) and Shigella sp. (n = 1). All isolates presented at least one of the virulence features tested (i.e. biofilm formation, haemolytic activity and production of siderophores), 70% carried the intI1 gene and 85% exhibited a multi-drug resistance phenotype. Plasmid-mediated quinolone resistance genes were detected in ciprofloxacin-resistant Enterobacteriaceae [aacA4-cr (40% of the isolates), qnrS (30%), qnrB (25%), and qnrVC (8%)], along with mutations in gyrA (70%) and parC (72%). Cefotaxime-resistant strains (n = 23) harbored bla (70%), bla (61%) and bla (39%). Among CTX-M producers, high-risk clones of E. coli (e.g. ST10 or ST131) and K. pneumoniae (ST17) were identified, most of which carrying bla. Ten out of 16 CTX-M producers were able to transfer bla to a recipient strain. Our results demonstrated the occurrence of multidrug resistant Enterobacteriaceae in the riverine plastisphere, harboring ARGs of clinical concern and exhibiting virulence traits, suggesting a contribution of MPs to the dissemination of antibiotic-resistant priority pathogens. The type of MPs and especially water contamination (e.g. by WWTPs discharges) seem to determine the resistome of the riverine plastisphere.

Sign in to start a discussion.

More Papers Like This

Article Tier 2

Size effects of microplastics on antibiotic resistome and core microbiome in an urban river

Scientists found that microplastics in an urban river serve as platforms for antibiotic-resistant bacteria and dangerous pathogens including Pseudomonas aeruginosa, Mycobacterium tuberculosis, and Legionella pneumophila. Larger microplastic particles harbored more antibiotic resistance genes, and the concentrations of these genes were much higher on plastic surfaces than in the surrounding water. This research raises concerns that microplastics in waterways could spread drug-resistant infections by providing a surface where dangerous bacteria thrive and share resistance genes.

Article Tier 2

Exploiting microplastics and the plastisphere for the surveillance of human pathogenic bacteria discharged into surface waters in wastewater effluent

Researchers placed small plastic particles in rivers upstream and downstream of a wastewater treatment plant and found that disease-causing bacteria, including E. coli and Klebsiella, quickly formed biofilms on them within 24 hours. These biofilms carried antibiotic resistance genes and virulence factors, showing that microplastics in waterways can serve as floating platforms for dangerous bacteria that pose risks to human health.

Article Tier 2

Antibiotic resistance genes and virulence factors in the plastisphere in wastewater treatment plant effluent: Health risk quantification and driving mechanism interpretation

Researchers found that microplastics in treated wastewater carry significantly more disease-causing bacteria, antibiotic resistance genes, and virulence factors on their surfaces compared to the surrounding water. This means microplastics released from wastewater treatment plants into rivers and lakes could spread antibiotic-resistant infections, posing a direct risk to communities that rely on these water sources.

Article Tier 2

Presence of microplastic particles increased abundance of pathogens and antimicrobial resistance genes in microbial communities from the Oder river water and sediment

Researchers incubated microplastic particles in water from the Oder River and found that bacteria growing on the plastic surfaces had significantly higher levels of disease-causing organisms and antibiotic resistance genes compared to surrounding water. This suggests that microplastics in rivers and waterways serve as platforms that concentrate harmful bacteria and help spread drug resistance, posing risks to communities that depend on these water sources.

Article Tier 2

Selective enrichment of bacterial pathogens by microplastic biofilm

Researchers incubated biofilms on microplastics and natural substrates in freshwater and found that microplastic surfaces selectively enriched bacterial pathogens and antibiotic resistance genes compared to rock and leaf surfaces. The study suggests that microplastics in waterways may serve as hotspots for harmful bacteria and contribute to the spread of antibiotic resistance in the environment.

Share this paper