|Abstract: Methidathion is a non-systemic organophosphorus insecticide. Genotoxicity potential of methidathion was evaluated in rat bone marrow cells (in vivo) using different doses based on LD50 by means of micronucleus test. MNNCE (Micronucleated Normocromatic Erythrocytes) and MNPCE (Micronucleated Polychromatic Erythrocytes), NDI (Nuclear Division Index) and NDCI (Nuclear Division Cytotoxicity Index), necrotic and apoptotic cells were recorded in rat’s bone marrow samples.|
Aim: our experiment is designed to assess the toxicity impact of Methidathion on rat'sbone marrow
In order to test the effect of Methidathion toxicity , three treatment conditions were evaluated. In the first experimental group, 0.1 of LD50of Methidathion was injected. In the second experimental group, 0.25 of LD50 of Methidathion was injected. and the last experimental group was injected with high dose 0.5 of LD50 and the exposure time to Methidathion was 30 days.
At the end of the experimental period, animals (Rats from each of the treatment groups, were sacrificed by cervical dislocation at the noon of the next day after the last injection. Both the femora were removed andcleaned with gauze by removing all the adhering muscle andtissue and subjected to micronucleus assay. The bone marrowwas flushed out from both femurs using 1 mL of RPMI 1640medium (bone marrow cells were pooled from both femurs of each animal) and centrifuged at 1000 rpm for 10 min. the cell were washed twice with phosphate buffered saline followed by centrifugation at 1000 rpm for 10 min.
Results:This study of the clastogenic effect of Methidathionusing micronucleus test revealed that there was no significant induction of micronucleus in rat bone marrow cells.Comparing results showed that control group and the experimental group have almost same value of MNE.Whereas the positive control showed more significant comparing with experimental and negative group. The microscopic investigation of micronuclei also not showed a variation in their shapes.