GLYPHOSATE: TOXIC OR NOT TOXIC, THIS IS THE QUESTION

The potential toxicity of Glyphosate-based herbicides (GBHs), a broad spectrum herbicides widely used in agricultural, industrial and urban areas, is a great matter of debate. Although considered non-toxic and not an irritant (EPA) and no carcinogenic to humans (EFSA), converging evidence suggests that GBHs pose serious health risk on non-target wildlife. Many studies demonstrate that GBHs threaten the reproduction interfering with the activity of aromatase, an important enzyme involved in the production of estrogen.1 Moreover, in fish and mammals GBHs cause the raise of oxidative stress markers and tissues alterations.2,3 Hence, the question about the glyphosate (Gly) toxicity is still open. To concur to answer to this question, we investigated the effects of Gly exposure on the wall lizard Podarcis sicula, a suitable bioindicator of soil pollution. Adult P. sicula specimens were divided in 3 groups (n=6): 2 groups exposed to pure Gly 0.1 and 1 mg/L, respectively, via gavage every other day for 3 weeks; group 3 received by gavage the same dose of tap water (100 μL). The results demonstrate that both Gly doses affect the male gonad. Spermatogenesis is slightly slower, spermatocytes II fuse to form rosette-shaped arrangement, spermatids appear damaged and cells in degeneration are evident in the tubules lumen. Changes in the expression of estrogen and androgen receptors and aromatase have been also detected. In females, the ovary is not affected by Gly exposure, no matter the dose. Livers show signs of suffering, regardless of the animals sex. The increase in melanocytes degranulation and nodular/cystic formations, mainly consisting of collagen fibers, have been observed. The liver of Gly-treated males also displays the biosynthetic alterations typical of an estrogenic contamination: hepatocytes, in fact, contain transcripts for both vitellogenin and estrogen receptors. Data suggest that Gly exposure in a vertebrate commonly inhabiting the fields potentially exposed to GBHs causes reproductive and tissue toxicity, with possible health implications for wild and breeding animals, as well human populations.