AGRO 144 |
| Fipronil's broad-spectrum neurotoxin activity selectively inhibits insect gamma aminobutyric acid receptors and results in hyper-excitation, paralysis and death. Non-insect arthropods also exhibit high sensitivity to Fipronil and its degradation products: Fipronil desulfinyl, Fipronil sulfide, Fipronil sulfone. The use of Fipronil on heavy clay soils may adversely influence crop rotation to the crustacean Procambarus clarkia (aka crawfish). A field study evaluating changes in the concentration of Fipronil and three degradates seven years after broadcast soil application for rice weevil control suggests that the published half-lives for Fipronil (75 – 213 days) underestimate the residual concentrations in the heavy clay soils characteristic of crawfish production areas. Analysis of shallow field soils for Fipronil and three degradates supports half-lives ranging from 152 to 631 days under southern Louisiana field conditions. The elimination or significant reduction of non-target arthropods in the rice/crawfish rotation collaborates the observed chemical persistence of biologically active pesticide reside. |
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New Developments and Issues in Agrochemical Sciences
8:45 AM-11:50 AM, Thursday, August 23, 2007 BCEC -- 259A, Oral
Division of Agrochemicals |