P-31: Chronic Exposure to Imidacloprid Reduced Sperm Content, Motility and Viability

s:2011:"Background: Imidacloprid (IMD) is a systemic insecticide which acts as an insect neurotoxin and belongs to a class of chemicals called the neonicotinoids which act on the central nervous system of insects. According to previous studies, IMD is rated as "moderately toxic" on an acute oral basis to mammals and according to United States Environmental Protection Agency this compound is classified as class II and III of toxic chemicals and requires warning label. This study was conducted to evaluate the possible adverse effect of chronic exposure to IMD on sperm content, motility and viability. Materials and Methods: Twenty four mature male rats were used. The animals were divided into control (received corn oil, 0.2 ml, once a day, orally), low dose IMDadministrated (received 112 mg/kg, once a day, orally) and high dose IMD-dosed (received 225 mg/kg, once a day, orally) groups. All animals received mentioned compounds for total of 60 days. The sperm count was performed based on WHO method for sperm count in rats. The sperm motility analyzed and the eosin-nigrosin staining was used for evaluating sperm viability. Results: The sperm count significantly (p<0.05) decreased in IMD-administrated animals in comparison to control group. Accordingly the high-dose-administrated animals were manifested with 34.34 ± 8.12 (×106) sperm content versus low-dose-received 42.12 ± 6.56 (×106) animals. Comparing percentage of immotile sperms between test and control group showed that, in IMDadministrated groups the sperm motility significantly (p<0.05) decreased in comparison to control animals. This impairment developed depending on dose. Light microscopic analyses showed remarkable increase in percentage of dead sperms in test groups depending on administrated dosage. Conclusion: According to present findings, chronic exposure to IMD can remarkably reduce sperm content, motility and viability, in turn it can influence the male fertilizing potential.";