Clastogenic Studies on Hexaconazole: A Triazole Fungicide in Rats

摘要

Hexaconazole is a triazole fungicide used in crop protection. Triazoles are one of the promising groups of fungicides that act by inhibiting the biosynthesis of ergosterol, an essential component of fungal cell membrane, via inhibition of cytochrome P450 dependent enzyme lanosterol 14α-demethylase. The present study is aimed to screen hexaconazole for its in vivo clastogenic potential in Wistar strain rats. The doses of hexaconazole selected in the present study were 182, 365 and 730 mg kg-1 for male rats and 506, 1012 and 2024 mg kg-1 for females. These doses were corresponding to 1/12th, 1/6th and 1/3rd, respectively of earlier reported oral LD50 values which were 2189 mg kg-1 in males and 6071 mg kg-1 in females. The in vivo clastogenic potential of hexaconazole was studied employing bone marrow chromosomal aberrations assay and micronucleus test following single exposure and multiple exposures to the drug. Results of bone marrow chromosomal aberrations assay indicated that hexaconazole in the tested doses is incapable of producing any structural or numerical aberrations in both male and female rats. Analysis of the bone marrow smears of the slides for micronucleated polychromatic erythrocytes revealed no significant increase in their number in hexaconazole treated rats. Multiple exposures also could not enhance their incidence significantly. These observations confirmed the results of chromosomal aberrations assay in this study where hexaconazole failed to produce and any aberrations. It further appears from the present study that hexaconazole had no effect on spindle formation during cell division.