title: Environmentally friendly formulations of alachlor and atrazine: preparation, characterization, and reduced leaching.
abstract: Atrazine and alachlor formulations were designed by encapsulating the herbicide molecules into phosphatidylcholine (PC) vesicles, which subsequently were adsorbed on montmorillonite. PC and montmorillonite are classified as substances of minimal toxicological risk by the U.S. EPA. PC enhanced alachlor and atrazine solubilities by 15- and 18-fold, respectively. A 6 mM PC:5 g/L clay ratio was found as optimal for PC adsorption on the clay. Active ingredient contents of the PC-clay formulations ranged up to 8.6% for atrazine and 39.5% for alachlor. Infrared spectroscopy showed hydrophobic interactions of herbicide molecules with the alkyl chains of PC, in addition to hydrophilic interactions with the PC headgroup. Release experiments in a sandy soil showed a slower rate from the PC-clay formulations than the commercial ones. Soil column experiments under moderate irrigation and bioactivity experiments indicate that a reduction in the recommended dose of alachlor and atrazine can be accomplished by using PC-clay formulations.
authors.affiliation: Institute of Natural Resources and Agrobiology, CSIC, Apdo. 1052, 41080 Sevilla, Spain.
authors.forename: Trinidad
authors.initials: T
authors.lastname: Sánchez-Verdejo
authors.forename: Tomás
authors.initials: T
authors.lastname: Undabeytia
authors.forename: Shlomo
authors.initials: S
authors.lastname: Nir
authors.forename: Jaime
authors.initials: J
authors.lastname: Villaverde
authors.forename: Celia
authors.initials: C
authors.lastname: Maqueda
authors.forename: Esmeralda
authors.initials: E
authors.lastname: Morillo
mesh_terms: D000081:Acetamides / Q000737:chemistry*; D000327:Adsorption; D001280:Atrazine / Q000737:chemistry*; D001546:Bentonite / Q000737:chemistry; D055772:Green Chemistry Technology / Q000379:methods*; D006540:Herbicides / Q000737:chemistry*; D010713:Phosphatidylcholines / Q000737:chemistry; D012987:Soil / Q000032:analysis; D012989:Soil Pollutants / Q000737:chemistry*
chemical_list: D000081:Acetamides; D006540:Herbicides; D010713:Phosphatidylcholines; D012987:Soil; D012989:Soil Pollutants; D001546:Bentonite; C000188:alachlor; D001280:Atrazine