Investigação da toxicidade, citotoxicidade e genotoxicidade de uma formulação comercial de 2,4-D (Diclorofenoxiacético) utilizando os organismos testes Allium cepa e Tradescantia pallida

• Ano de defesa: 2015
• Autor(a) principal: Souza, Cleiton Pereira de [UNESP]
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Estadual Paulista (Unesp)
• Palavras-chave em Português: Herbicides; Herbicidas; Toxicidade - Testes; Citotoxicidade; Toxicologia genética; Auxina; Indicadores (Biologia)
• Link de acesso: http://hdl.handle.net/11449/123747

The most prominent selective herbicide, developed in the 1940s, is the 2,4-dichlorophenoxyacetic acid (2,4-D), with an auxin whose mode of action is similar to the natural auxin, but with greater stability in plant and therefore, more effective than the natural hormone. The constant and indiscriminate use of this agrochemical class has caused serious damage to the environment. Given the above the present study aimed to investigate the toxicity of the commercial 2,4-D herbicide DMA 806 BR®, using the Allium cepa and Tradescantia pallida as models. It was still aimed to compare the results obtained by investigating a commercial formulation with data already constants in the literature that investigated the active ingredient (2,4-diclofenoxiacético acid) to check for additive interaction and/or synergic ingredient and other substances contained in the commercial product. Three concentrations of commercial 2,4-D herbicide were tested to assess the toxic potential effects: field concentration, half and a quarter of field concentration. One hundred seeds of A. cepa were subjected to continuously germination for evaluating the toxicity, cytotoxicity and genotoxicity of the three tested concentrations. The positive control was performed with the herbicide Trifluralin® (0.95 μL mL-1) and negative control with distilled water. The experiment was conducted in triplicate. To assess genotoxicity by means of the micronucleus test with T. pallida, 10 young flowers stems with closed buds were collected and exposed to three different concentrations of 2,4-D Commercial for 8 hours, followed by 24 hours recovery in distilled water under constant aeration. The positive control was performed with methyl methane sulfonate positive control (7.7 x 10-3 μL ml-1) and negative control in distilled water. Three thousand tetrads were counted per treatment. Data distribution for normality was performed with the Shapiro-Wilk test, the parametric test was performed...