Pre- and postnatal toxicity of the commercial glyphosate formulation in Wistar rats

Glyphosate is the active ingredient and polyoxyethyleneamine is the surfactant present in the herbicide Roundup® formulation commercialized in Brazil. The aim of this study was to assess the reproductive effects of glyphosate-Roundup® on male and female offspring of Wistar rats exposed during pregnancy and lactation. Dams were treated orally with water or 50, 150 or 450 mg/kg glyphosate during pregnancy (21-23 days) and lactation (21 days). These doses do not correspond to human exposure levels. The results showed that glyphosate-Roundup® did not induce maternal toxicity but induced adverse reproductive effects on male offspring rats: a decrease in sperm number per epididymis tail and in daily sperm production during adulthood, an increase in the percentage of abnormal sperms and a dose-related decrease in the serum testosterone level at puberty, and signs of individual spermatid degeneration during both periods. There was only a vaginal canal-opening delay in the exposed female offspring. These findings suggest that in utero and lactational exposure to glyphosate-Roundup® may induce significant adverse effects on the reproductive system of male Wistar rats at puberty and during adulthood.