Cytotoxicity effect of malathion and its residues in stored tiriticum aestivum grains and vicia faba seeds

The genotoxic effect of the insecticide malathion and its residues was studiedin Triticum aestivum [wheat] grains and Vicia faba [broad beans] seeds. Wheatgrains and bean seeds were treated with 8, 24, and 40 mg malathion/kg andstored for three and six months. Treatment of the grains [seeds] withmalathion caused a statistically significant decrease in the mitotic index anda significant percentage of chromosome abnormalities after storage for threeand six months. The decrease in the mitotic index indicates inhibition ofcell division. Malathion induced a number of mitotic abnormalities. Thehighest percentage reached 8.73 +/- 0.22 [P <0.01] in root-tip meristems ofVicia faba seeds after treatment of seeds with 40 mg/kg and storage for threemonths. This percentage decreased after storage of the treated seeds for sixmonths, to 3.59 +/- 1.24 [P <0.05]. The percentage of chromosomeabnormalities in the root-tip cells of treated wheat grains was significantafter storage for three and six months. Prolongation of the storage period to six months had no effect on thepercentage of the induced abnormalities. Chromosome stickiness was observedin a high percentage in the root-tip cells of the treated grains [seeds]stored for three and six months. The above-described results indicated thatthe grains [seeds] did not recover after storage for six months. Thenon-recovery of the stored grains [seeds] may be attributed to the permanenteffect of malathion and its residues. The results indicated that malathion iscytotoxic

Induction of chromosome aberrations in mouse germ cells by the organophosphorous insecticides Dursban and Dichlorvos and sperm abnormalities in the treated mice

The ability of the two organophosphorous insecticides "Dursban" and "Dichlorvos" to induce chromosomal abnormalities in mouse spermatocytes was investigated. Male swiss mice were intraperitoneally [i.p] injected with the doses 2, 4, 10 mg/kg[-1] body wt. of "Dursban" [dissolved in 0.1 DMSO] and 2.8, 3.5, 7 mg/kg[-1] body wt. of "Dichlorvos" and samples were taken 6. 24 and 48 hrs after the treatment. The percentage of chromosomal aberrations in diakinesis - metaphase I cells increased by increasing the concentration of both insecticides and reached its maximum 24 hrs following i.p. injection, its highest value was 19.3 +/- 1.61 [P < 0.01] and 16.5 +/- 0.63 [P < 0.01] 24 hrs after treatment with the highest dose of "Dursban" and "Dichlorvos" respectively. Compared with 25.5 +/- 0.97 [P < 0.01], 24 hrs after i.p. injection with mitomycin C" at 1 mg/kg[-1] body wt. The two insecticides induced abnormal chromosomal associations including univalents [autosomal and x-y univalents] and chains, as well as structural and numerical chromosome aberrations. Dursban and Dichlorvos induced a dose-dependent increase in the percentage of abnormal sperm heads. Its highest value was 15.48 +/- 0.73 [P < 0.01] and 10.8 +/- 0.89 [P < 0.01] after oral treatment with Dursban and Dichlorvos respectively, compared with 18.3 +/- 1.10 [P < 0.01] after treatment with "Mitomycin C"

Induction of micronuclei in mouse bone-marrow by the carbamate insecticides carbofuran

The ability of carbofuran to induce micronuclei in mouse bone marrow cells was studied. Different routes of application for carbofuran were tested to cover the different possibilities for human exposure to the pesticide. The different routes of administration of carbofuran caused toxicity to bone marrow indicated as significant increase in the percentage of polychromatic erythrocytes [PEs] over that of the control. Carbofuran at a dose of 0.025 mg kg-1 body weight affected the percentage of PEs with micronuclei significantly. It reached 2.6% after i.p. injection compared with 0.7% for the control and 2.8% after oral treatment by gavage compared with 0.5% for the control. Feeding mice for three months with Vicia faba and soya bean seeds treated with carbofuran at 15 mg kg-1 and stored for 30 weeks caused a significant increase in the percentage of micronucleated PEs. This was attributed to the penetration of carbofuran inside the seeds during the storage period. The results revealed a clastogenic potential of carbofuran and its residues, in stored seeds, in mouse bone marrow

Induction of chromosome aberrations and sister chromatid exchange in mouse bone-marrow by the insecticide dursban

The ability of the insecticide "Dursban" to induce chromosomal aberrations and sister chromatid exchange was tested in mouse bone marrow. Mice were intraperitoneally injected with the dose 4 m kg [-1] body wt. of the insecticide dissolved in 0.1 DMSO. Samples were taken 6, 24 and 48 hours after intraperitoneal injection. The results indicated that "Dursban" at the tested doses is a potent inducer of chromosome aberrations in mouse bone marrow. The percentage of chromosomal aberrations increased by increasing the time of treatment and reached its maximum 24 hours following intraperitoneal injection, where it reached 25.5 +/- 0.95. The aberrations induced were chromatid and chromosome gaps, fragments, breaks and deletions. The doses 10, 20 and 25 mg kg [-1] body wt. of the insecticide caused a significant and dose dependent increase in the frequency of sister chromatid exchange in mouse bone marrow cells. It reached 9.13 +/- 0.27 per cell after treatment with the highest tested does of "Dursban" compared with 4.52 +/- 0.42 per cell in the solvent. This indicates that "Dursban" is a weak inducer of sister chromatid exchange in mouse bone marrow

Genotoxic effect of the insecticide methomyl lannate in mouse bone-marrow

The cytogenetic effect of the insecticide "Methomyl" was studied in mouse bone-marrow cells. the ability of "Methomyl" to induce micronuclei, chromosomal aberrations and sister chromatid exchanges was investigated. Intra-peritoneal injection of "Methomyl" with the dose 4 mg Kg-1b.wt. induced a significant increase in the percentage of micronucleated polychromatic erythrocytes, the same dose caused marrow toxicity as indicated by a significant increase in the percentage of polychromatic erythrocytes. The doses 4 and 6 mg "Methomyl" Kg-1 b.wt. induced a significant increase in the percentage of chromosomal aberrations after i.p. injection. The chromosomal aberrations induced by "Methomyl" were mainly structural including gaps, fragments, breaks and deletions. Methomyl induced also significant and dose dependent increase of sister chromatid exchanges SCE's. The present results indicated that "Methomyl" is genotoxic in mouse bone-marrow cells. Care must be taken to the use of this insecticide in agriculture