AGRO 53 |
| Phase partition and persistence determine the fate, transport, and ecotoxicological risks of a chemical in the environment. Although pyrethroids have been in use for many years, most of our knowledge on their phase distribution and persistence is limited to soils and little information is available for sediments. In addition, conventional methods for determining adsorption coefficient Kd are known to be problematic for strongly hydrophobic compounds and do not allow characterization of KDOC that is considered as a key variable for regulating chemical bioavailability in aquatic systems. This first part of this presentation will provide an overview of measured KOC and KDOC values for a number of pyrethroid compounds, identify information gaps, and discuss the advantages of using selective detection methods for improving measurement of phase distribution coefficients. The second part of this talk will be devoted to discussion of half-lives of pyrethroids in sediments, degradation mechanisms, and the information gaps. |
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Synthetic Pyrethroids and Surface Water Quality
8:30 AM-11:20 AM, Monday, 11 September 2006 San Francisco Marriott -- Salon 3, Oral
Division of Agrochemicals |