Toxic and teratogenic effects of fenitrothion, BHC and carbofuran on embryonic development of the frog Microhyla ornata.

The toxic and teratogenic effects of fenitrothion, benzene hexachloride (BHC) and carbofuran on the embryos and tadpoles of the frog Microhyla ornata were investigated for a period of 96 h. Of the three pesticides tested, fenitrothion was found to be most toxic and teratogenic and carbofuran the least toxic while BHC was intermediate. Tadpoles were observed to be more sensitive than the embryos to these pesticides. Abnormalities observed in embryos and tadpoles were the occurrence of blisters on the body, distention of body cavities, curvature of the body axis, poor blood circulation, poor pigmentation, retarded growth, loss of balance and abnormal behaviour.