Is The Herbicide Glyphosate Killing Our Earthworms — And Why That Would Matter

Could the herbicide glyphosate, commonly found in Monsanto’s RoundUp, be killing our earthworms? A study published in the scientific journal Water, Air & Soil Pollution last quarter found that when researchers examined the toxicity of pesticides and herbicides, their effects on earthworms and other species in the soil are not adequately examined.

Authors of the study, which focused on the “sublethal effects” of glyphosate on earthworms, was co-authored by Marina Santadino, of the National University of General Sarmiento in Argentina, Carlos Coviella, an agronomic engineer from National University of Luján, and Fernando Momo, also of the National University of General Sarmiento.

The researchers performed an experiment that studied the effects of gylphosate on the earthworm Eisenia fetida. In the study, the adult earthworms were separated into three groups. The first group of earthworms was exposed to no gylphosate. The second group of earthworms was exposed to a typical dose of gylphosate that is advised for perennial weeds. The third group of earthworms were exposed to a double dose of glyphosate.

Each week, each group of earthworms was examined. Two samples were gathered from each group. The samples were analyzed for the number of “adults, individual weight, number of cocoons, and presence and number of young earthworms,” according to the authors who performed a matrix analysis of the data. The results showed that the earthworms that were not exposed to glyphosate had a positive population growth rate. Both of the glyphosate-exposed groups had a negative growth rate.



  1. Here we are in the Year of the Soil, and these guys want to discuss if it’s possible that we might have too many earthworms. It takes earthworms one year to generate 1 inch of soil with an average population. Without earthworms, and relying on nature to generate 1 inch of soil using other means, it takes 100 years. Call me silly, but I really don’t we can have too many earthworms at this point, and I do know that when you use Monsanto’s herbicides even if you don’t kill the earthworms, you certainly chased them out of the area of application. The same holds true for artificial fertilizers, although researchers to date have never figured out if the earthworms leave because the artificial fertilizers have improved the soil so much that there’s nothing for the earthworms to do, or that the earthworms leave because the artificial fertilizers are poisonous to the earthworms.