MICRONUCLEI FORMATION IN BONE-MARROW CELLS OF RATS TREATED WITH MEOTHRIN (SYNTHETIC PYRETHROID)

The production of micronuclei in rat bone marrow cells by the syntheti c pyrethroid insecticide meothrin was investigated. Three different do ses of meothrin were orally administered to rats for 14 consecutive da ys. All tested doses of meothrin increased the frequency of micronucle ated polychromatic erythrocytes but the increase was statistically sig nificant only at the two highest doses. Meothrin also affected the rat e of bone marrow cell proliferation, as determined by changes in the r atio of polychromatic erythrocytes to normochromatic erythrocytes. (C) 1997 by John Wiley & Sons, Ltd.