Impact of glyphosate herbicide exposure on sperm motility, fertilization, and embryo-larval survival of pejerrey fish (Odontesthes bonariensis)

Abstract

The herbicideglyphosate is widely used in agricultural practices around the world, can reachaquatic environments and potentially impact non-target organisms. This studyaimed to investigate the effects of glyphosate exposure (both as the activeingredient and its formulated product) on sperm quality, fertilization successand development of pejerrey (Odontesthesbonariensis), a native freshwater fish species from Argentina. Resultsrevealed a statistically significant increase in sperm motility at the highestconcentration of the formulated product. In contrast, exposure to the activeingredient resulted in a decrease in certain motility parameters. Fertilizationassays and embryonic development showed no notable effects in exposed groups.There were no effects in the morphology or temporal evolution of the embryonicstages, nor in the hatching rate. In contrast, larvae exposed to the formulatedproduct exhibited a significant increase in mortality rates, reaching 100%mortality at the highest concentration within a few hours. These findingssuggest differential susceptibility between embryos and larvae to glyphosateexposure and highlight the importance of simultaneously assessingthe impacts of both the active ingredient and the entire formulation ofglyphosate on freshwater fish reproduction and development.