A biocide delivery system composed of nanosilica loaded with neem oil is effective in reducing plant toxicity of this biocide. (1st February 2022)

• Record Type: Journal Article
• Authors: Goetten de Lima, Gabriel; Wilke Sivek, Tainá; Matos, Mailson; Lundgren Thá, Emanoela; de Oliveira, Ketelen Michele Guilherme; Rodrigues de Souza, Irisdoris; de Morais de Lima, Tielidy Angelina; Cestari, Marta Margarete; Esteves Magalhães, Washington Luiz; Hansel, Fabrício Augusto; Morais Leme, Daniela
• Is Part Of: Environmental pollution. Volume 294(2022)
• Publication Date: 2022-02-01
• Subjects: Safer pesticides -- Neem oil -- Nanosilica -- Allium cepa -- Phytotoxicity -- Genetic damages; Pollution -- Periodicals; Pollution -- Environmental aspects -- Periodicals; Environmental Pollution -- Periodicals; Pollution -- Périodiques; Pollution -- Aspect de l'environnement -- Périodiques; Pollution -- Effets physiologiques -- Périodiques; Pollution; Pollution -- Environmental aspects; Periodicals; Electronic journals; 363.73
• DOI: 10.1016/j.envpol.2021.118660
• Languages: English
• ISSNs: 0269-7491

Abstract

Abstract: One possible way to reduce the environmental impacts of pesticides is by nanostructuring biocides in nanocarriers because this promotes high and localized biocidal activity and can avoid toxicity to non-target organisms. Neem oil (NO) is a natural pesticide with toxicity concerns to plants, fish, and other organisms. Thus, loading NO in a safe nanocarrier can contribute to minimizing its toxicity. For this study, we have characterized the integrity of a nanosilica-neem oil-based biocide delivery system (SiO2 NP#NO BDS) and evaluated its effectiveness in reducing NO toxicity by the Allium cepa test. NO, mainly consisted of unsaturated fatty acids, was well binded to the SiO2 NP with BTCA crosslinker. Overall, this material presented all of its pores filled with the NO with fatty acid groups at both the surface and bulk level of the nanoparticle. The thermal stability of NO was enhanced after synthesis, and the NO was released as zero-order model with a total of 20 days without burst release. The SiO2 NP#NO BDS was effective in reducing the individual toxicity of NO to the plant system. NO in single form inhibited the seed germination of A. cepa (EC50 of 0.38 g L −1 ), and the effect was no longer observed at the BDS condition. Contrarily to the literature, the tested NO did not present cyto- and geno-toxic effects in A. cepa, which may relate to the concentration level and composition. Highlights: Neem oil mainly composed of unsaturated fatty acids caused toxicity to Allium cepa . SiO2 NP is a nanocarrier capable of controlling neem oil (NO) release. Neem oil phytotoxicity is eliminated by controlling its release into a nanocarrier. SiO2 -nanocarrier is not toxic to plant and contributes to sustainable agriculture. Tested NO did not present toxicity due to test concentrations and composition.