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 USEPA. PC enhanced 15-and 18-fold alachlor and atrazine solubilities, respectively. A 6 mM PC:5g/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.3

Potential effect of chemical and thermal treatment on the Kinetics, equilibrium, and thermodynamic studies for atrazine biosorption by the Moringa oleifera pods

“…The atrazine functional groups were investigated by FTIR spectroscopy (Supplementary Data, Figure SD 1). The main observed bands of this organic molecule were a reactive group hexameric aromatic ring, attached to a chlorine, and two amine groups, a primary and a secondary amine …”

Reduced metribuzin pollution with phosphatidylcholine–clay formulations

“…The band at 3437 cm −1 was assigned to the OH stretching vibration of water bound to the PC headgroup, whereas the band at 1245 cm −1 was assigned to the asymmetric stretching vibration of PO 2 − . Moreover, the band at 1473 cm −1 was attributed to CH 2 scissoring, and the bands at 2850 and 2920 cm −1 were attributed to symmetric and asymmetric CH 2 stretching vibrations respectively 10…”

“…In a previous study, the authors optimised the adsorption of PC on montmorillonite for the preparation of slow‐release herbicide formulations 9. This system proved to be very effective at reducing the leaching of poorly water‐soluble herbicides such as atrazine and alachlor 10. In the present study, a similar approach was evaluated with metribuzin, a highly water‐soluble herbicide.…”

Modificação química de argilas: desafios científicos e tecnológicos para obtenção de novos produtos com maior valor agregado

“…36 Relata-se também o uso de vesículas como as de, por exemplo, fosfatidilcolina para o encapsulamento de espécies herbicidas para posterior intercalação na argila. 37 Essa estratégia pode ser útil quando se trata de uma molécula aniônica. O uso excessivo de produtos agroquímicos, contaminando o ambiente e deixando resíduos em alimentos, tem sido noticiado recentemente no Brasil.…”