Antibiotic Resistance

Also see glyphosate, dicamba 

Glyphosate and Other Weed Killers Create Antibiotic Resistant Bacteria in Agricultural Soils   (Beyond Pesticides, February 24, 2021) 'Soil sprayed with weedkillers glyphosate, glufosinate, or dicamba are likely to contain higher amounts of antibiotic resistant bacteria, according to research published earlier this month in the journal Molecular Biology and Evolution. Each year in the United States, at least 2 million people develop an antibiotic resistant infection, and over 23,000 die. Authors of the study say widespread herbicide use is likely playing a role. “Our results suggest that the use of herbicides could indirectly drive antibiotic resistance evolution in agricultural soil microbiomes, which are repeatedly exposed to herbicides during weed control,” said Ville Friman, PhD of the University of York in the United Kingdom.   Contrary to the pesticide industry’s claim that these chemicals break down quickly and become inert by binding to soil particles, large proportions of the herbicides remained in the soil at the end of the 60-day experiment, stemming back from the first application. For glyphosate 18% remained, glufosinate 21%, and dicamba 34%.  .. scientists determined that herbicide exposure triggers evolutionary pressures on bacteria similar to those exposed to antibiotics...  “Interestingly, antibiotic resistance genes were favoured at herbicide concentrations that were not lethal to bacteria,” said Dr. Friman. “This shows that already very low levels of herbicides could significantly change the genetic composition of soil bacterial populations. Such effects are currently missed by ecotoxicological risk assessments, which do not consider evolutionary consequences of prolonged chemical application at the level of microbial communities.”    'The field '(s)amples matched up closely to the results of the microcosm experiment:'