|13 December 2018
THIRD WORLD NETWORK BIOSAFETY AND SUSTAINABLE AGRICULTURE INFORMATION SERVICE
Dear Friends and Colleagues
Herbicides Increase Antibiotic Resistance Evolution in Bacteria
Antibiotic resistance in our pathogens is caused by human activity and is a major challenge for public health. Recent research has found that some of the world’s most widely used herbicides like Roundup (glyphosate) and Kamba (dicamba) can increase the rate of antibiotic resistance development in bacteria by a factor of up to 100,000 times faster than occurs without the herbicide. Both herbicides are used on genetically modified crops engineered to tolerate them.
The scientists studied multiple bacteria including Salmonella andE. coli. E. coli accounts for 17.3 percent of clinical infections requiring hospitalization. The study found that even when herbicides make bacteria weaker or stronger, it still develops resistance, and when the chemicals in herbicides are combined with antibiotics, the rate of antibiotic resistance increases because the genetic makeup in the bacteria changes. A further finding is that bacteria may acquire antibiotic resistance in the environment at rates substantially faster than predicted from laboratory conditions.
The scientists concluded that neither reducing the use of antibiotics nor the discovery of new ones may be sufficient strategies to avoid the post-antibiotic era. This is because bacteria may be exposed to other non-antibiotic chemicals, like herbicides, that predispose them to evolve resistance to antibiotics more quickly. The study adds to a growing body of evidence that herbicides used on a mass industrial scale in agriculture, but not intended to be antibiotics, can have profound effects on bacteria, with potentially negative implications for medicine’s ability to treat infectious diseases caused by bacteria. Thus, antibiotic resistance may increase even if total antibiotic use is reduced, and new ones are invented, unless other environmental exposures are also controlled.
With best wishes,