Sister-chromatid exchanges and chromosomal aberrations in chick embryos after treatment with the fungicide maneb

The genotoxic potential of a commercial formulation of the fungicide maneb (Maneb 80, containing 80% manganese ethylenebisdithiocarbamate as active ingredient) in chick embryos was evaluated, using as genetic end-points the frequency of sister-chromatid exchanges (SCE) and of chromosomal aberrations. Unincubated eggs were dipped in 0, 0.5, 1.5, 4.5, 13.5 or 27 g/l maneb aqueous solutions for 30 sec. Eggs were then incubated for 4 days. Maneb significantly increased SCE values at 13.5 g/l and at 27 g/l (means 1.33 and 1.74) over the control value (mean 0.87). The concentration of 27 g/l, which corresponds to 10.8 times the recommended maximum application level for use in the field, also resulted in a high mortality rate. No clastogenic effects following exposure to maneb were observed.