Researchers say commonly used herbicides make bacteria more resistant to antibiotics

Commonly used herbicides can cause bacteria to develop resistance to antibiotics much more quickly.

Researchers at New Zealand's University of Canterbury and Lincoln University have studied how large-scale industrial herbicides affect bacteria in recent research pointing to a harmful link. Posted in peerj On Friday, the study revealed the speed of antibiotic resistance and the ease with which this could happen.

"Herbicides are among the most widely used and widely dispersed manufactured products on Earth. One can regularly expect some form of exposure for people, pets, and livestock, "said Jack Heinemann, a professor at the University of Canterbury and author of the. article Newsweek. "At the same time, antibiotics are used at high levels, especially in humans, pets and livestock. As a result, the combination of exposures to the bacteria that live on us is almost guaranteed. "

Heinemann and his team have already researched this and published articles in 2015 and 2017 showing the link between antibiotic resistance and herbicides. The new findings in this paper show that even when herbicides weaken or strengthen bacteria, they still develop resistance. When the chemicals in herbicides are associated with antibiotics, the rate of antibiotic resistance increases because of the change in the genetic make-up of the bacteria.

"That's why we call the herbicides of gasoline for a fire," Heinemann explained. Antibiotics do not stay where we use them – they spread through excrement, urine and drains. As antibiotics go, they encounter bacteria that may become resistant. The use of herbicides only enhances areas in which antibiotics could be infected with these potentially resistant bacteria.

"However, we were surprised at the potency of these formulations to enhance the resistance of bacteria populations and the possible low concentration of the herbicide for this to happen. The concentrations we tested were well below the application levels, "said Heinemann.

According to the study, Roundup Herbicide contains chemicals that could accelerate resistance. JOSH EDELSON / AFP / GETTY IMAGES

The researchers studied several bacteria, including Salmonella and E. coli. E. coli accounts for 17.3% of clinical infections requiring hospitalization, according to the Broad Institute. In some cases, resistance has evolved 100,000 times faster when exposed to herbicides such as Roundup, glyphosate or Kamba, based on dicamba. Scientists still do not know if these reactions directly affect our ability to treat diseases, but they think it's likely.

"Even small changes in resistance can complicate or even compromise antibiotic therapy. In many cases, the treatment may fail and the reasons not be diagnosed. Effects such as those we observe could explain some of these cases, "said Heinemann. However, it is still possible to start working to avoid the effects.

"The first step is to recognize that there is a problem. Once this is done, we and others, including the chemical manufacturers to which we are routinely exposed, can study sublethal effects on bacteria, "said Heinemann. "Where effects are found, appropriate monitoring can be done to limit the effects. We believe that it is time for safety regulators to start requesting such studies from manufacturers when they submit their products for regulatory approval. "