| Abstract: | The distribution and fate of 14C]carbofuran were studied in model earlyseason rice/fish and late-season rice/fish ecosystems after its application by respectively soil incorporation and broadcasting. The differences observed in the behaviour of the insecticide in these two rice/fish ecosystems indicated the important effect of the different application methods on the fate of the chemical in the environment. The radioactive residues in the paddy water, rice plants and fish were much lower when the pesticide was incorporated into the soil surface layer. An obvious vertical movement of carbofuran residues occurred in the paddy soil profile. Bound residues constituted the majority of the residues in the paddy soil, rice plants and fish tissues. 3-Hydroxy- and 3-ketocarbofuran and carbofuran phenol were tentatively identified as the main degradation products in the paddy water, paddy soil, rice plants and fish. |
