Herbicides and the echoes of resistance

SynCell News • March 06, 2021

Herbicides are among the most widely used products of the chemical industry in agriculture and one of the key components in the sustainability of one of the biggest food sources of our constantly growing society. And also, they are a source of antibiotic resistant bacteria.

As anyone would have imagine, these chemical damage microbes in soil, produce stress on them and allow these bacteria to develop resistance to chemicals that couple with the one to antibiotics. The old story told again, but from a different source.

Their names? Glyphosate, glufosinate and dicamba, commonly used chemicals that elicit mutations on microbial ecosystems in soil that carry antibiotic resistance genes. They are often found in combination with others in widely available commercial herbicides whose control and impact in both hard and time-consuming to evaluate.

Specially used for weed control, different studies have shown than the use of herbicides indirectly drive antibiotic resistance evolution in agricultural soil microbiomes.

Antibiotic resistance genes appearance are favored at herbicide concentrations that are non-lethal to bacteria.

What becomes more worrisome is that the antibiotic resistance genes appearance are favored at herbicide concentrations that are non-lethal to bacteria, meaning that extremely low levels of these chemicals can have huge consequences in the development of this crisis. Therefore, even keeping herbicide concentrations below the standards of ecotoxicological impact, the damage is and will be already done.

If we take the antibiotic resistance-derived from weed control and add it to other common sources affecting agriculture, such as manure residues, sewage sludge, biosolids, and soil itself, we have a growing problematic of catastrophic proportions.

So once more, knowing the source and how little we can do about it, the question remains: will we be prepared for it?