Effects of Dissolved Organic Matter on Permethrin Bioavailability to Daphnia Species
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- 作者：Weichun Yang ; Frank Spurlock ; Weiping Liu ; and Jianying Gan
- 刊名：Journal of Agricultural and Food Chemistry
- 出版年：2006
- 出版时间：May 31, 2006
- 年：2006
- 卷：54
- 期：11
- 页码：3967 - 3972
- 全文大小：84K
- 年卷期：v.54,no.11(May 31, 2006)
- ISSN：1520-5118
文摘
Synthetic pyrethroids are widely used insecticides in both agricultural and urban environments. Recentstudies show frequent appearances of pyrethroid residues in runoff effluents and sediments, whichstimulated concerns over the potential ecotoxicological implications. Pyrethroids are known to havetwo contrasting characteristics, high aquatic toxicity and strong affinity for the solid phase, that maynegate the actual toxicity in a multiphased system. This study evaluated the effect of dissolved organicmatter (DOM) on the pyrethroid uptake by and acute toxicity to water-column invertebrates usingpermethrin as a model compound. During the bioassays, the freely dissolved permethrin concentrationwas simultaneously measured using poly(dimethylsiloxane) (PDMS) fibers as a biomimetic surrogate.The presence of DOM consistently decreased permethrin uptake and increased its LC50. For instance,compared to the DOM-free treatment, the LC50 of permethrin to Ceriodaphnia dubia in a pond watercontaining DOM at 10 mg L-1 increased from 0.56 to 1.03 
g L-1, whereas the bioaccumulationfactor by Daphnia magna decreased by 56%. Permethrin accumulation on the PDMS fiber closelymimicked permethrin uptake by D. magna. Statistical analyses suggest that permethrin associatedwith DOM was completely unavailable to D. magna or C. dubia. The effect of DOM on permethrinbioavailability appeared to depend also on the source of the DOM. These results indicate that theinhibitory role of DOM should be considered in the development of toxicologically relevant waterquality limits and in monitoring protocols for permethrin and other pyrethroids in runoff effluents andsurface streams that ubiquitously contain DOM.Keywords: Bioavailability; biomimetic sampling; synthetic pyrethroids; dissolved organic matter;effluent toxicity
g L-1, whereas the bioaccumulationfactor by Daphnia magna decreased by 56%. Permethrin accumulation on the PDMS fiber closelymimicked permethrin uptake by D. magna. Statistical analyses suggest that permethrin associatedwith DOM was completely unavailable to D. magna or C. dubia. The effect of DOM on permethrinbioavailability appeared to depend also on the source of the DOM. These results indicate that theinhibitory role of DOM should be considered in the development of toxicologically relevant waterquality limits and in monitoring protocols for permethrin and other pyrethroids in runoff effluents andsurface streams that ubiquitously contain DOM.Keywords: Bioavailability; biomimetic sampling; synthetic pyrethroids; dissolved organic matter;effluent toxicity