Ação mutagênica do inseticida organofosforado temefós em células de medula óssea de camundongos Mutagenic effects of the organophosphate insecticide temephos on mice bone marrow cells

The mutagenic effects of organophosphorate temephos on mice bone marrow cells was investigated through the micronucleus formation test. Doses of temephos (27.75; 55.5 e 111.0 mg/kg) were orally administered to males and females Swiss Webster mice. Cyclophosphamide (CPA, 25 mg/kg) per via i.p. and water (10 mL/kg) were administered in mice as positive and negative control groups, respectively. Mutagenic effects were evaluated from 24h to 72h after giving a single dose, and after nine doses of 111.0 mg/kg weekly administered. Ten thousand bone marrow cells per experimental group were analyzed. In the positive controls, the percentages of polychromatic erythrocytes micronucleus (PCEMN) at 24h after a single dose were1.63% in male and 2.77% in female mice. No PCEMN was observed in the negative controls group. Gradually increasing temephos doses induced PCEMN in 2.61, 3.50, and 3.69% males and 1.02, 1.37, and 1.33% females, respectively. After 72h, CPA caused 0.05% of PCEMN in both males and