Glyphosate Exposure Linked to Rise in Antibiotic-Resistant Bacteria, New Research Suggests
New research from Argentina indicates a potential connection between exposure to glyphosate, a widely used herbicide and the increasing prevalence of antimicrobial resistance (AMR). The study, published in Frontiers in Microbiology, assessed glyphosate resistance in both environmental bacteria from soil samples and bacteria isolated from Argentinian hospitals.
Glyphosate and Antibiotic Resistance: A Growing Concern
Previous research has suggested that exposure to glyphosate can create selective pressure, favoring the growth of antibiotic-resistant bacterial strains in soil. Though, the link to bacteria causing infections in clinical settings has been less clear. This new study aimed to bridge that gap by examining bacterial isolates from both agricultural environments and hospitals.
Study Methodology and Findings
Researchers collected 68 bacterial isolates from soil within a nature reserve in the Parana delta, an area surrounded by agricultural land where glyphosate is heavily used. They likewise analyzed 19 multidrug-resistant (MDR) bacterial species commonly found causing infections in hospitals, including Enterobacter cloacae.
The hospital bacteria were, as expected, resistant to multiple antibiotics, but also demonstrated high levels of resistance to glyphosate and glyphosate-based herbicides. Environmental bacteria showed varying degrees of glyphosate resistance, with the most resistant strains closely related to those found in the hospitals. Specifically, environmental isolates within the Enterobacter family exhibited the highest tolerance to the herbicide.
Analysis of the bacterial family tree revealed that the environmental strains with the highest glyphosate resistance clustered closely with the MDR strains from hospitals. Whole-genome sequencing showed that the most glyphosate-resistant environmental isolates possessed a greater number of genetic mechanisms also associated with AMR.
Implications for Public Health
“These results suggest that weedkillers—which, unlike antibiotics, are widely applied in agricultural environments—may have the unintended side-effect of selecting for AMR among bacterial communities within the soil,” explained Daniela Centron, PhD, the senior author of the study, in a press release. The researchers suggest that the widespread use of glyphosate in agriculture may contribute to the selection of clinically relevant, resistant bacteria.
Argentina’s Glyphosate Use and AMR
Argentina is a major consumer of glyphosate, largely due to its extensive genetically modified (GM) soy production. As reported in Settler Colonial Studies, the country’s agricultural landscape has become deeply intertwined with agrochemicals. The extensive use of glyphosate in this context may be a key factor in the observed link between herbicide exposure and AMR. Research from the University of Buenos Aires has been focused on analyzing bacterial resistance to glyphosate and antibiotics in both environmental and clinical isolates within Argentina.
Future Research and Environmental Risk Assessments
The study authors emphasize the need for further research to fully understand the complex relationship between glyphosate exposure and AMR. They also recommend that the potential for AMR development be incorporated into environmental risk assessments of glyphosate and other biocidal agents.
Key Takeaways
- A new study suggests a link between glyphosate exposure and antibiotic resistance.
- Bacteria from agricultural soils and hospitals in Argentina both showed high levels of glyphosate resistance.
- The most glyphosate-resistant environmental bacteria were genetically similar to antibiotic-resistant strains found in hospitals.
- Researchers suggest that glyphosate may contribute to the selection of antibiotic-resistant bacteria in the environment.