Reduced metribuzin pollution with phosphatidylchline clay formulations
| Autor: | Undabeytia López, Tomás, Recio, Esther, Maqueda Porras, Celia, Morillo González, Esmeralda, Gómez-Pantoja, Eulalia, Sánchez Verdejo, Trinidad |
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| Přispěvatelé: | Ministerio de Educación y Ciencia (España), Junta de Andalucía, European Commission |
| Rok vydání: | 2011 |
| Předmět: | |
| Zdroj: | Digital.CSIC. Repositorio Institucional del CSIC instname |
| Popis: | 8 pages, 5 tables, 6 figures, 40 references. BACKGROUND: Metribuzin is a widely used herbicide that has been identified as a groundwater contaminant. In this study, slow-release formulations of metribuzin were designed by encapsulating the active ingredient in phosphatidylcholine (PC) vesicles and adsorbing the vesicles ontomontmorillonite. RESULTS:Themaximumactive ingredient content intheslow-release formulationswas246g kg−1. Infrared spectroscopy results revealed that the hydrophobic interactions between metribuzin and the alkyl chains on PCwere necessary for encapsulation. In addition,water bridges connecting the herbicide and the PC headgroup enhanced the solubility ofmetribuzin in PC. Adsorption experiments in soils were performed to evaluate the relationship between sorption and leaching. Funnel experiments in a sandy soil revealed that the herbicide was not irreversibly retained in the formulation matrix. In soil column experiments, PC–clay formulations enhanced herbicide accumulation and biological activity in the top soil layer relative to a commercial formulation. PC–clay formulations also reduced the dissipation of metribuzin by a factor of 1.6–2.5. CONCLUSIONS: A reduction in the recommended dose of metribuzin can be achieved by employing PC–clay formulations, which reduces the environmental risk associated with herbicide applications.Moreover, PC andmontmorillonite are non-toxic and do not negatively affect the environment. This research was supported by the MEC Project CTM2009-07425 and Junta de Andalucía Project P09-RNM4581. Both projects received funding by the European Social Fund. |
| Databáze: | OpenAIRE |
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