AGRO 57 |
| Recent studies reported enantioselective degradation of synthetic pyrethroid in both laboratory and field samples. The significance of such observations would be of limited importance if the enantiomers of the given chiral compound have comparable toxicity to non-target organism. Enantioselectivity in the chronic toxicity and biotransformation of pyrethroids is essentially unknown in aquatic organisms. Certain pyrethroids and their metabolites have been shown to bind to estrogen receptors in the yeast estrogen screen (YES) bioassay. In this study we investigated possible enantioselectivity in the endocrine disruption effects of synthetic pyrethroids. Preliminary evaluation of vitellogenin induction in juvenile (4 – 5 weeks old) Japanese medaka indicated mild vitellogenin induction following 7 days exposure to selected pyrethroids. Similarly, in vitro evaluation using primary rainbow trout hepatocytes indicated stereoselective induction vitellogenin-mRNA at levels significantly higher from that of controls. Enantioselectivity in all these processes could result in ecotoxicological effects that may be important considerations in future risk assessment and regulatory decisions. |
|
New Developments and Issues in Agrochemical Sciences
8:00 AM-11:00 AM, Monday, August 20, 2007 BCEC -- Exhibit Hall - B2, Poster
Sci-Mix
Division of Agrochemicals |