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Agricultural protection agents used in soil and crops, when applied conventionally, may have their activity impaired against pests and vectors due to their volatilization, photodegradation, leaching, and other unwanted occurrences caused by weather conditions. These problems cause economic and environmental damage due to the high volume of applications necessary for the farmer to achieve the desired results. The indiscriminate use of free pesticides causes high environmental pollution because these compounds are cumulative in soil, water and vegetation, sometimes causing air contamination, which can cause health issues in local workers and the death of animals. In contrast, nanopesticides are an alternative emerging technology that allows the controlled release of active compounds, improving pest control performance and turning it more sustainable and in line with the concept of precision agriculture. The use of nano-delivery systems for pesticide agents uses nanostructures capable of altering the release kinetics of these compounds, providing the plantation with an adequate amount for pest elimination. This paper presents an overview of nanopesticides, addresses some current concepts of sustainability, reviews and analyzes the latest developments regarding these nanomaterials, and provides an update on their advantages and disadvantages.

ABSTRACT. The high cost of biodiesel production is mainly linked to the price of raw material.This factor has favored the use of alternative fats and oils such as those used in frying. Since biodiesel can be obtained from several vegetable and animal raw materials, the physicochemical characteristics of the fuel may vary considerably. One of these characteristics is the fatty acid composition. It directly affects the oxidative stability of biodiesel, which can be impaired when the fuel undergoes exposure to sunlight, metals, oxygen and high temperatures. In order to improve the oxidative stability of biodiesels produced from waste frying oil some studies involving blends of different raw materials have been carried out. In this sense, this work aimed to assess the characteristics resulting from the blending of soybean waste frying oil with other waste biodiesels in what concerns to oxidation. The blends of fatty materials were obtained by means of a 2² factorial design. The induction periods of biodiesel blends were enough to meet the ASTM D6751 standard. Swine fat was responsible for the increase in the induction period values.Keywords: pequi oil, swine fat, transesterification, waste biodiesel.Estabilidade oxidativa de blendas de biodiesel de fritura RESUMO. O alto custo de produção do biodiesel está ligado principalmente ao preço da matéria-prima e este fator tem favorecido a utilização de óleos e gorduras alternativos como os de fritura. Uma vez que o biodiesel pode ser obtido a partir de diversas matérias-primas vegetais e animais, as características físico-químicas do combustível são bastante variáveis, dentre elas a composição em ácidos graxos que afeta diretamente a estabilidade oxidativa do biocombustível. A estabilidade oxidativa de biodiesel pode ser prejudicada quando o combustível sofre exposição à luz solar, metais, oxigênio e altas temperaturas, principalmente. A fim de melhorar a estabilidade oxidativa de biodieseis produzidos a partir de óleos e gorduras residuais de fritura, vem sendo realizados alguns estudos que envolvem blendas de diferentes matérias-primas. Neste sentido o presente trabalho tem como objetivo avaliar as características resultantes da blendagem de biodiesel residual de soja com outros biodieseis residuais do ponto de vista oxidativo. As blendas dos materiais graxos foram obtidas a partir de planejamento fatorial 2². Os períodos de indução das blendas de biodiesel foram suficientes para atender à norma ASTM D6751, sendo que a gordura suína foi responsável pelo aumento destes valores.Palavras-chave: óleo de pequi, gordura suína, transesterificação, biodiesel residual.