Development, validation, and application of a method for the GC-MS analysis of fipronil and three of its degradation products in samples of water, soil, and sediment

A method for the identification and quantification of pesticide residues in water, soil, and sediment samples has been developed, validated, and applied for the analysis of real samples. The specificity was determined by the retention time and the confirmation and quantification of analyte ions. Linearity was demonstrated over the concentration range of 20 to 120 µg L(-1), and the correlation coefficients varied between 0.979 and 0.996, depending on the analytes. The recovery rates for all analytes in the studied matrix were between 86% and 112%. The intermediate precision and repeatability were determined at three concentration levels (40, 80, and 120 µg L(-1)), with the relative standard deviation for the intermediate precision between 1% and 5.3% and the repeatability varying between 2% and 13.4% for individual analytes. The limits of detection and quantification for fipronil, fipronil sulfide, fipronil-sulfone, and fipronil-desulfinyl were 6.2, 3.0, 6.6, and 4.0 ng L(-1) and 20.4, 9.0, 21.6, and 13.0 ng L(-1), respectively. The method developed was used in water, soil, and sediment samples containing 2.1 mg L(-1) and 1.2% and 5.3% of carbon, respectively. The recovery of pesticides in the environmental matrices varied from 88.26 to 109.63% for the lowest fortification level (40 and 100 µg kg(-1)), from 91.17 to 110.18% for the intermediate level (80 and 200 µg kg(-1)), and from 89.09 to 109.82% for the highest fortification level (120 and 300 µg kg(-1)). The relative standard deviation for the recovery of pesticides was under 15%.

Própolis na dieta de abelhas Apis mellifera L. e seu efeito no sistema imune, expressão de genes após o desafio bacteriano e detoxificação frente ao agroquímico fipronil

Pós-graduação em Zootecnia - FMVZ

Mecanismos de toxicidade dos metabólitos do fipronil, dessulfinil e sulfona, em mitocôndrias isoladas de fígado de rato

Pós-graduação em Ciência e Tecnologia Animal - FEIS

Própolis na dieta de abelhas Apis mellifera L. e seu efeito no sistema imune, expressão de genes após o desafio bacteriano e detoxificação frente ao agroquímico Fipronil

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Efeitos da exposição ao pesticida fipronil nas alterações pressóricas em ratos acordados

Pós-graduação em Ciências Biológicas (Farmacologia) - IBB

Eficiência de nematoides entomopatogênicos e inseticidas químicos contra Sphenophorus levis e Leucothyreus sp. em cana-de-açúcar

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Cat flea (Ctenocephalides felis) infestation in quarantined marsh deer (Blastocerus dichotomus) populations

Marsh deer (Blastocenrs dichotomus) were captured for a research progam in Brazil and maintained in quarantine stations. After 60 days, fleas were detected on animals and identified as Ctenocephalides felis felis. Elimination of the infestation was difficult. Animal treatment with a fipronil-based compound was effective, and subsequently captured animals were treated prophylactically. Some animals remained infested, and some died from the infestation.

Sensibilidade de fungos entomopatogênicos a agroquímicos usados no manejo da cana-de-açúcar

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Inseticidas químicos e microbianos no controle da lagarta-do-cartucho na fase inicial da cultura do milho

The objective this work was to evaluate the effect of microbial and chemical insecticides on the fall armyworm Spodoptera frugiperda in the development initial phase of crop corn. The work was lead in the experimental area of the State University of Mato Grosso do sul, in Cassilandia (MS) city. The treatments had been: 1) control; 2) fipronil; 3) thiametoxan; 4) Beauveria bassiana (0,5 kg of p.c/ha), 5) Beauveria bassiana (1 kg of p.c/ha), 6) teflubenzuron and 7) spinosad, in the doses and recommended way of application. After the tenth second after the emergency of the plants (DAE), had been day applied the treatments in foliar spraying (PF), being evaluated to the 2, 9, 15 and 21 days after the application (DAA), the number of small caterpillars (lesser that 1,5 cm) for parcel in 20 showed plants. The applied results show that teflubenzuron and spinosad in PF to the 12 DAE had been most efficient (71 and 83% respectively). The microbial's insecticides had not differed significantly from the chemical insecticides in the percentage of plants attacked for the pest and the 15 and 21 DAA.

Laboratory Assessment of two Active Ingredients for Control of Coptotermes gestroi (Isoptera: Rhinotermitidae)

The subterranean termite Coptotermes gestroi Wasmann (Isoptera: Rhinotermitidae) is a pest of major economic importance in urban environments of southeastern Brazil. Compared to using pesticides for termite control, termite bait products target termites more specifically and also address environmental contamination issues. In this point of view, we performed two different bioassays ill order to evaluate the efficacy of boric acid and fipronil against different populations of C. gestroi. The results showed that concentration between 2000 and 3000 ppm of boric acid caused approximately 100 percent mortality ill termites. Concentrations between 0.01 and 0.0001 ppm of fipronil resulted in 100% termite mortality after 2 wk exposure. The data displayed a fast mortality of termites contaminated with fipronil, even with small concentrations, and therefore it is riot a Suitable product to be used ill baits against C gestroi. The present Study showed a delayed toxicity of boric acid against the subterranean termite C gestroi which suggests a need for further field tests.

Foraging Behavior and Mortality of Ectatomma brunneum (Hymenoptera, Formicidae) in Simultaneous Exposure to Ant Baits and Conventional Diet in Laboratory

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Efeito de inseticidas em insetos predadores em culturas de algodão

Com o objetivo de verificar o efeito de inseticidas em insetos predadores em cultura de algodão (Gossypium hirsutum L.), instalaram-se, em 1993-1994, dois experimentos, um no campo, e outro, em laboratório. No experimento realizado no campo, os tratamentos foram: Fipronil 200 SC (75 g/ha de i.a.); Fipronil 800 WDG (64, 80 e 100 g/ha de i.a.); Endosulfan 350 CE (700 g/ha de i.a.); e testemunha. em laboratório, além das formulações à base de Fipronil foi utilizado o Paration metílico 600 CE (480 g/ha de i.a.). Fipronil foi seletivo para os artrópodes predadores (Scymnus sp., Geocoris ventralis, Cycloneda sanguinea e Doru lineare) no campo, e a Cycloneda sanguinea (L.), em laboratório, e pode ser recomendado em programas de manejo integrado de pragas na cultura do algodoeiro para o controle de Alabama argillacea (Rueb.), e Anthonomus grandis Boh. Endosulfan foi seletivo em relação a Scymnus sp., Geocoris ventralis Thomazini e Doru lineare (Eschs) no campo, com uma redução dos insetos inferior a 30%, e o Paration metílico não foi seletivo para C. sanguinea em laboratório.

Method for the evaluation of insecticidal activity over time in Atta sexdens rubropilosa workers (Hymenoptera: Formicidae)

The active ingredients used in the formulation of toxic baits for leaf-cutting ants (Hymenoptera: Formicidae) should possess a delayed action defined as an insecticidal activity whereby worker mortality is ≤15% at 24 hours and ≥90% at 21 days. Serious shortcomings have occurred in the search for new active ingredients, such as the initial selection of fenoxycarb, copper oxychloride and diflubenzuron, compounds considered very promising but whose inefficiency was verified only later, indicating methodological problems. In view of this situation, we developed a classification method for insecticidal activity over time using workers of the leaf-cutting ant Atta sexdens rubropilosa Forel. The insecticides used were fipronil, sulfluramid GX071HB and sulfluramid GX439, vehicled in an attractive pasty formulation prepared based on citrus pulp. The results obtained were consistent from a toxicological viewpoint and agreed with the literature in terms of the control of colonies. Sulfluramids were found to possess a delayed action at a broad range of concentrations, in agreement with the fact that these substances are highly effective in the control of all leaf-cutting ant species. The smaller range of concentrations of fipronil with delayed action is probably related to its lower efficacy for species more difficult to control such as Atta capiguara (Forti et al. 2003). We discuss the importance of relating behavioral particularities to the specific feeding habits of leaf-cutting ants, with methodological adequacy of the assessment of insecticides aimed at toxic baits.

Laboratory assessment of two active ingredients for control of coptotemes gestroi (Isoptera: Rhinotermitidae)

The subterranean termite Coptotermes gestroi Wasmann (Isoptera: Rhinotermitidae) is a pest of major economic importance in urban environments of southeastern Brazil. Compared to using pesticides for termite control, termite bait products target termites more specifically and also address environmental contamination issues. In this point of view, we performed two different bioassays in order to evaluate the efficacy of boric acid and fipronil against different populations of C. gestroi. The results showed that concentrations between 2000 and 3000 ppm of boric acid caused approximately 100 percent mortality in termites. Concentrations between 0.01 and 0.0001 ppm of fipronil resulted in 100% termite mortality after 2 wk exposure. The data displayed a fast mortality of termites contaminated with fipronil, even with small concentrations, and therefore it is not a suitable product to be used in baits against C. gestroi. The present study showed a delayed toxicity of boric acid against the subterranean termite C. gestroi which suggests a need for further field tests.

Efeito da imersão de mudas com fertilizante e cupinicida no crescimento de dois clones de eucalipto sob duas condições de umidade no substrato

Pós-graduação em Ciência Florestal - FCA