Weedkiller & Superbugs: Soil’s Unexpected Role | Phys.org

Agricultural soils treated with glyphosate, a widely used herbicide, are harboring genes that confer resistance to antibiotics, potentially contributing to the spread of “superbugs” in hospitals, according to new research.

The study, detailed by Phys.org, indicates a correlation between the presence of glyphosate in soil and an increased prevalence of genes that develop bacteria resistant to multiple drugs. These genes, researchers found, can transfer between bacteria, accelerating the development of antibiotic resistance.

While the precise mechanisms are still under investigation, scientists hypothesize that glyphosate may disrupt the natural microbial balance in the soil, creating an environment where resistant bacteria thrive. The herbicide’s impact on bacterial cell walls may also play a role, increasing the likelihood of gene transfer. This finding adds a new dimension to concerns about the overuse of glyphosate in agriculture.

The emergence of antibiotic-resistant bacteria, often referred to as superbugs, poses a significant threat to global public health. Infections caused by these bacteria are more difficult and sometimes impossible to treat, leading to longer hospital stays, higher medical costs, and increased mortality rates.

The research builds on previous findings that have linked agricultural practices to the spread of antibiotic resistance. The use of antibiotics in livestock, for example, is known to contribute to the development of resistant bacteria, which can then spread to humans through the food chain or direct contact. The discovery that a widely used herbicide like glyphosate may also be a factor raises further concerns about the unintended consequences of modern agricultural practices.

SciTechDaily reported on a related development, noting research into a failed antibiotic that is now being explored as a potential weedkiller. This highlights the complex interplay between antibiotic development and agricultural chemistry, and the potential for compounds initially designed for one purpose to have unforeseen effects in other areas.

Concerns surrounding genetically modified organisms (GMOs) also intersect with this issue, as Michigan State University researchers have noted the frequent association of GMO crops with the emergence of superweeds and secondary pests. While not directly linked to antibiotic resistance in the current study, the broader context of agricultural intensification and its impact on microbial ecosystems is relevant.

Further complicating the issue, research published by Phys.org suggests that microplastics in soil could also contribute to the spread of drug-resistant superbugs. Microplastics can act as vectors for bacteria, facilitating the transfer of resistance genes between different species. The combined effect of glyphosate, microplastics, and other agricultural chemicals on soil microbial communities remains largely unknown.

As of today, no official statement has been released by the Environmental Protection Agency regarding the implications of this research for glyphosate regulation. Further studies are planned to investigate the long-term effects of glyphosate exposure on soil microbial communities and the potential for human exposure to antibiotic resistance genes through the food supply.