Avaliação do efeito da interação entre o íon metálico Cu (II) e o pesticida malathion em amostras de solo
Arquivos
Data
2021-12-17
Autores
Lima, Ana Layla Carvalho de 
Orientadores
Akamatu, Eliana Maíra Agostini Valle
Tipo
Trabalho de conclusão de curso
Título da Revista
ISSN da Revista
Título de Volume
Resumo
Com a utilização sem fiscalizaçao de diversos pesticidas no meio ambiente devido a sua eficiência no tratamento de pestes em pequena e larga escala, estas substâncias acabam se tornando um grande motivo de preocupação ao solo e água. Sabe-se que suas moléculas apresentam grupos funcionais que podem interagir com íons metálicos, formando novos compostos no meio ambiente e alterando suas características, propriedades e biodisponibilidade no ambiente. Dessa forma, o intuito deste trabalho foi estudar a interação entre o pesticida malathion e o íon metálico cobre (II) em amostras de solo. Para este fim, foram utilizados técnicas eletroanalíticas e espectroscópicas.Inicialmente foi realizado um estudo do comportamento eletroquímico das espécies por meio da técnica de voltametria, onde foi observada a interação entre as duas espécies através do deslocamento de seus potenciais de oxidação e redução, confirmada pela técnica de espectroscopia UV-Vis. Posteriormente o efeito dessa complexação foi avaliado em amostras de solo, que foram digeridas por digestão ácida sob refluxo, seguida da determinação do teor de cobre total nas amostras com e sem a adição do pesticida por espectrometria de absorção atômica com chama. Com esta metodologia empregada, não foi possível verificar a interação entre as espécies, indicando que o cobre pode não estar disponível para interagir com o pesticida no meio, uma vez que pode estar complexado com a matéria orgânica do solo, formando uma espécie altamente estável nas condições do meio.
With the unsupervised use of several pesticides in the environment due to their efficiency in the treatment of small and large-scale pests, these substances become a major cause of concern to the soil. It is known that its molecules have functional groups that can interact with metal ions, forming new compounds in the environment and changing their characteristics, properties and bioavailability in the environment. Thus, the aim of this work was to study the interaction between the pesticide malathion and the metallic ion copper (II) in soil samples. For this purpose, electroanalytical and spectroscopic techniques were used. Initially, a study of the electrochemical behavior of the species was carried out using the voltammetry technique, where the interaction between the two species was observed through the displacement of their oxidation and reduction potentials, confirmed by the UV-Vis spectroscopy technique. Afterwards, the effect of this complexation was evaluated in soil samples, which were digested by acid digestion under reflux, followed by the determination of the total copper content in the samples with and without the addition of the pesticide by flame atomic absorption spectrometry. According to this methodology used, it was not possible to verify the interaction between species, indicating that copper may not be available to interact with the pesticide in the medium, as it may be complexed with soil organic matter, forming a highly stable species under the conditions of the environment.
With the unsupervised use of several pesticides in the environment due to their efficiency in the treatment of small and large-scale pests, these substances become a major cause of concern to the soil. It is known that its molecules have functional groups that can interact with metal ions, forming new compounds in the environment and changing their characteristics, properties and bioavailability in the environment. Thus, the aim of this work was to study the interaction between the pesticide malathion and the metallic ion copper (II) in soil samples. For this purpose, electroanalytical and spectroscopic techniques were used. Initially, a study of the electrochemical behavior of the species was carried out using the voltammetry technique, where the interaction between the two species was observed through the displacement of their oxidation and reduction potentials, confirmed by the UV-Vis spectroscopy technique. Afterwards, the effect of this complexation was evaluated in soil samples, which were digested by acid digestion under reflux, followed by the determination of the total copper content in the samples with and without the addition of the pesticide by flame atomic absorption spectrometry. According to this methodology used, it was not possible to verify the interaction between species, indicating that copper may not be available to interact with the pesticide in the medium, as it may be complexed with soil organic matter, forming a highly stable species under the conditions of the environment.