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In vitro and in vivo studies demonstrate non-mutagenicity of the herbicide metolachlor

 

 

Cesar Koppe Grisolia; Iris Ferrari

Departamento de Genética e Morfologia, Instituto de Ciências Biológicas, Universidade de Brasilia, 70910-900 Brasília, DF, Brasil. Fax: (061) 273-4942. E-mail: grisolia@guarany.cpd.unb.br. Send correspondence to C.K.G.

 

 

ABSTRACT

The herbicide metolachlor was evaluated for genotoxic potential. Metolachlor did not induce micronuclei in mice, however at 40 mg/kg it significantly decreased the percentage of polychromatic erythrocytes, which is a cytotoxic effect. Metolachlor did not induce chromosomal aberrations in human lymphocytes in vitro, but 2.0 µg/ml culture medium resulted in cytotoxicity, decreasing the mitotic index significantly. The indirect exposure test was carried out by adding plasma from metolachlor-pretreated rats to the human lymphocyte cultures. There was no indication of clastogenicity by metolachlor metabolites. On the other hand, plasma of cyclophosphamide-pretreated rats had a significant clastogenic effect.

Keywords: mutagenicity; herbicide; metolachlor.

 

 

REFERENCES

Buhler, D.R. and Williams, D.E. (1988). The role of biotransformation in the toxicity of chemicals. Aquat. Toxicol. 11: 19-28.

Darroudi, F. and Natarajan, A.T. (1985). Cytostatic drug activity, a bioassay for detecting mutagenicity of directly and indirectly acting chemicals, an evaluation of 20 chemicals. Mutat. Res. 143: 263-269.

Natarajan, A.T., de Bruijin, E.A., Leefalang, P., Slee, P.H.Th.J., Mohn, G.P. and Driessen, 0. (1983). Induction of chromosomal alterations as an assay for cytogenetic drug activity in plasma. Mutat. Res. 121: 39-45.

Pintér, A., Torok, G., Surjan, A., Csik, M., Kelecsenyi, Z. and Kocsis, Z. (1992). Genotoxic activity of chloroacetanilidetype herbicides. Mutat. Res. 271: 115-200.

Plewa, M.J. (1978). Activation of chemicals into mutagens by green plants: A preliminary discussion. Environ. Health Perspect. 27: 45-50.

Roloff, B., Belluck, D. and Meisner, L. (1992). Cytogenetic effects of cyanazine and metolachlor on human lymphocytes exposed in vitro. Mutat. Res. 281: 295-298.

Schmid, W. (1975). The micronucleus test. Mutat. Res. 31:9-15.