US EPA

4441135 

Technical Report 

Evidence for vapor loss of 14C carbofuran from rice plants 

Siddaramappa, R; Watanabe, I 

1979 

Yes 

Bulletin of Environmental Contamination and Toxicology
ISSN: 0007-4861
EISSN: 1432-0800 

Springer-Verlag 

PESTAB/80/0110 

Environ 

4-5 

544-551 

English 

10.1007/BF01770001 

PESTAB. Studies were performed to determine vapor loss rates of the pesticide carbofuran from rice plants. In experiment 1 seedlings were placed through a hole in a stopper with the roots in a solution of 14C carbofuran and kept in the dark. In experiment 2 seedlings were treated in the same way, but exposed to light. In experiment 3 the carbofuran in vapor was trapped in ethylene glycol from plants grown as in experiment 1. Solutions of radioactive pesticides were analyzed by liquid scintillation counting. Radioactivity was also determined in leaf blades, stems, and roots. After 10 days, about 2/3 of the radioactivity was lost from the solution in experiment 1. There was a slight accumulation in the plant parts--0.128, 0.026, and 0.155 x 104 cpm in leaves, stems and roots, respectively; 2.021 x 104 cpm were unaccounted for. Experiment 2 showed that lighted conditions cause a greater loss of pesticide by vaporization. More transpiration loss was observed under higher conditions. The vapor loss of radioactivity was seen to increase rapidly up to 10 days, compared to a gradual increase up to 20 days in root zone application. 

insecticide; radioisotope; animal experiment; carbofuran c 14; higher plant; rice; Autoradiography; Carbofuran; Gases; Insecticides, Carbamate; Oryza sativa; Pesticide Residues; Time Factors; Volatilization