Potential hazards of glyphosate on rabbit retina

Abstract

Background/aim Retinal degeneration is a leading cause of vision loss. Exposure to pesticides is a high risk factor of retinal degeneration. The aim of the work is to investigate the molecular structural changes of retina associated with the topical application of glyphosate (GLP), an organophosphorus compound pesticide.Materials and methods Twenty rabbits were randomly categorized into four groups. Group I served as control (n=5, 10 eye balls) and the other three groups (each composed of five rabbits) received topical instillation of 100 μl twice a day of GLP in three concentrations of 0.12, 0.97, and 7.8 mg/kg, respectively. After 1 week, eyes were enucleated and retinae were removed and prepared for analysis by infrared spectroscopy (Fourier-transform infrared spectroscopy).Results The regions of NH–OH spectra indicated a significant decrease (P<0.05) in wavenumber and restriction of two components related to strO–H and OHasym band after application of GLP. The protein secondary structure components in terms of β sheets, alpha helices and β turns were changed in groups III and IV. Also the fingerprint regions indicate changes in the surrounding environment after all doses of GLP.Conclusion Certain retinal structure modifications may lead to the degeneration of retina after topical exposure to GLP in rabbits. So this herbicide should be handled with caution. National governments must introduce a GLP reduction program because of its damage effect on retina function.