Agrotóxicos e Meio Ambiente: Inserção do Tema na Escola Através de uma Abordagem Interdisciplinar

http://dx.doi.org/10.5902/2179460X12823The rural workers and their families are exposed to many risk situations concerning their health during the performance of their activities in the field. Human and environmental contamination by agrochemicals is far from being a simple problem, in large part due to the diversity of social, economical and cultural determinants that permeate them. Given the complexity of the topic, the main objective of this study was to capacitate young high school students, coming from families of small farmers, from the rural area of the city of Agudo-RS, to act as multipliers of knowledge on the importance of the correct use of agrochemicals and the risks they may cause to human health and the environment, highlighting the importance of the use of Good Farming Practices. An interdisciplinary approach was used with the objective of situating the students in the social and cultural environment. Considering that this study was elaborated with the purpose of training young multipliers of information, the main didactic strategies used were reading and interpretation of texts, group discussions, study of the environment, collective project and interaction with the community, which demanded the active participation of the students in the capacitating and learning processes.http://dx.doi.org/10.5902/2179460X12823O trabalhador rural e sua família estão expostos à diversas situações de risco à saúde durante o desempenho de suas atividades no campo. A contaminação humana e ambiental por agrotóxicos está longe de ser um problema simples, muito em parte pela diversidade de determinantes de ordem social, econômica e cultural, que o permeiam. Diante da complexidade do tema, o objetivo principal deste estudo foi capacitar jovens estudantes do Ensino Médio, filhos de pequenos agricultores, da zona rural do município de Agudo-RS, para atuarem como multiplicadores dos conhecimentos sobre a importância da utilização correta de agrotóxicos e os riscos que os mesmos podem causar à saúde humana e ao meio ambiente, enfatizando a importância do uso das Boas Práticas Agrícolas. Utilizou-se uma abordagem interdisciplinar com o objetivo de situar os alunos no ambiente social e cultural. Considerando que este trabalho foi elaborado com o propósito de formar jovens multiplicadores de informações, as principais estratégias didáticas utilizadas foram a leitura e interpretação de textos, discussão em grupos, estudo do meio ambiente, projeto coletivo e interação com a comunidade, que exigiram a participação ativa dos alunos no processo de capacitação e aprendizagem

Protective effects of diet containing rutin against trichlorfon-induced muscle bioenergetics disruption and impairment on fatty acid profile of silver catfish Rhamdia quelen

Trichlorfon is an organophosphate insecticide that is widely used on fish farms to control parasitic infections. It has been detected in freshwater ecosystems as well as in fishery products. There is a growing body of evidence to suggest that certain feed additives may reduce or prevent pesticide-induced toxicity in fish. The aim of the present study was to determine whether acute exposure to trichlorfon would alter bioenergetic homeostasis and alter fatty acid profiles in muscles of silver catfish (Rhamdia quelen). We also sought to determine whether rutin prevents or reduces these effects. Cytosolic and mitochondrial creatine kinase (CK) and activities of complexes II-III and IV in muscle were significantly inhibited by exposure to 11 mg/L trichlorfon for 48 h compared to effects in the unexposed group. Total content of polyunsaturated fatty acids (omega-3 and omega-6) were significantly lower in muscle of silver catfish exposed to 11 mg/L trichlorfon for 48 h than in the unexposed group. Addition of 3 mg rutin/kg feed increased CK activity and prevented inhibition of complex IV activity, as well as preventing all alterations of muscle fatty acid profiles elicited by exposure to trichlorfon. No significant differences were observed between groups with respect to muscle adenylate kinase or pyruvate kinase activities, as well as total content of saturated and monounsaturated fatty acids. Our findings suggest that exposure (48 h) to 11 mg trichlorfon/L water inhibits cytosolic and mitochondrial CK activity in muscle. Trichlorfon also affects activities of complexes II-III and IV in respiratory chain, with important consequences for adenosine triphosphate production. The pesticide alters fatty acid profiles in the fish and endangers human consumers of the product. The most important finding of the present study is that inclusion of rutin improves bioenergetic homeostasis and muscle fatty acid profiles, suggesting that it reduces trichlorfon-induced muscle damage

Aumento da resposta analítica por meio da otimização do sistema de injeção sem divisão de fluxo em cromatografia gasosa empregando a lei dos gases ideais

This paper reports the development of an easy, fast and effective procedure for the verification of the ideal gas law in splitless injection systems in order to improve the response. Results of a group of pesticides were used to demonstrate the suitability of the approach. The procedure helps establish experimental parameters through theoretical aspects. The improved instrumental response allowed extraction with lower sample volumes, the minimization of time and costs and the simplification of sample preparation

Mobilization and transport of pesticides with runoff and suspended sediment during flooding events in an agricultural catchment of Southern Brazil

International audienceBrazil is one of the largest consumers of pesticides in the world, and these chemicals present a high contamination risk for the country’s water bodies. The mechanisms of mobilization and transport of pesticides from cropland to river systems are controlled by runoff and erosion processes occurring at the catchment scale. In addition to the excessive use of pesticides, the transport processes of these substances are also accelerated by inadequate soil management and the absence of soil conservation measures at the catchment scale. The current research relied on hydrological monitoring to investigate the transport and persistence of pesticides in response to hydrological dynamics. The study was conducted in the Conceição River watershed where runoff and suspended sediment fluxes are continuously monitored at the outlet. This study area is representative of the grain production system in southern Brazil including the application of large amounts of pesticides combined with extensive runoff and erosion problems. Sample collection in the river for pesticide analysis included the analysis of both water and suspended sediment. The sediment deposit analysis was performed in a single location at 4 depths. Results demonstrate the occurrence of pesticides including simazine, 2,4-D, carbendazim, imidacloprid, tebuconazole, propiconazole, tetraconazole, and trifloxystrobin in water, while glyphosate and AMPA were detected in suspended sediments, and AMPA and carbendazim were found in sediment deposits. The study demonstrated the strong dependence of the mechanisms of pesticide mobilization and transport in the catchment with the intra- and interevent variability of hydro-sedimentary processes. Pesticide detections can be related to several factors, including the magnitude of the rainfall event, the period of pesticide application, or the transport of suspended sediment. All these factors are correlated, and the mechanisms of transportation play an important role in the connections between sink and sources. The results suggest that pesticide monitoring should take into account the runoff and erosion pathways in each particular catchment, and it should especially include the monitoring of major rainfall events for identifying and quantifying the occurrence of pesticides in the environment. The transport of pesticides indicates to be potentiated by intensive pesticide use, the magnitude of rainfall-runoff events, and the absence of runoff control measures (e.g., terracing). These results demonstrate that water and soil conservation techniques should be planned and coordinated at the watershed scale to reduce the connectivity of water and sediment flows from agricultural areas to river systems with the implementation of effective runoff control practices. This will control the mobilization agents (runoff), as well as limit the connection between the sources and the water bodies

Modern techniques of sample preparation for pesticide residues determination in water by liquid chromatography with detection by diode array and mass spectrometry

Submitted by Sabrina Andrade ([email protected]) on 2011-12-29T14:17:09Z No. of bitstreams: 1 Principais técnicas de preparo de amostra para a determinação de resíduos de agrotóxicos em água por cromatografia líquida com detecção por arranjo de diodos e por espectrometria de massas.pdf: 587149 bytes, checksum: 722380c67dda0b081e76e30bb59df8a5 (MD5)Approved for entry into archive by Barbara Milbrath([email protected]) on 2012-01-07T23:31:35Z (GMT) No. of bitstreams: 1 Principais técnicas de preparo de amostra para a determinação de resíduos de agrotóxicos em água por cromatografia líquida com detecção por arranjo de diodos e por espectrometria de massas.pdf: 587149 bytes, checksum: 722380c67dda0b081e76e30bb59df8a5 (MD5)Made available in DSpace on 2012-01-07T23:31:35Z (GMT). No. of bitstreams: 1 Principais técnicas de preparo de amostra para a determinação de resíduos de agrotóxicos em água por cromatografia líquida com detecção por arranjo de diodos e por espectrometria de massas.pdf: 587149 bytes, checksum: 722380c67dda0b081e76e30bb59df8a5 (MD5) Previous issue date: 2011The determination of pesticide residues in water samples by Liquid Chromatography require sample preparation for extraction and enrichment of the analytes with the minimization of interferences to achieve adequate detection limits. The Solid Phase Extraction (SPE), Solid Phase Microextraction (SPME), Stir Bar Sorptive Extraction (SBSE) and Dispersive Liquid-Liquid Microextraction (DLLME) techniques have been widely used for extraction of pesticides in water. In this review, the principles of these sample preparation techniques associated with the analysis by Liquid Chromatography with Diode Array Detection (LC-DAD) or Mass Spectrometry (LC-MS) are described and an overview of several applications were presented and discussed

RICE SEED TREATMENT AND RECOATING WITH POLYMERS: PHYSIOLOGICAL QUALITY AND RETENTION OF CHEMICAL PRODUCTS

The use of chemical seed treatment is an important tool in the protection of seedlings and has contributed to the increase of rice yield (Oryza sativa L.). The objective of this study was to evaluate the physiological quality and quantify the retention of chemical products in rice seeds treated with insecticide and fungicide coated with polymers. Six seed treatments were used: control, phytosanitary treatment and phytosanitary treatment and coating with the polymers, Florite 1127®, GV5® Solid Resin, Polyseed CF® and VermDynaseed®. The physiological quality was evaluated by the test of germination and vigor by first count tests, germination speed index, shoot length, radicle length, seedling dry mass and sand emergence. To determine the retention of the active ingredients metalaxyl-M and thiamethoxam, an equipment called extractor was used. The experiment was organized in a completely randomized design (DIC) and the averages were separated by the Scott Knott test (p≤0.05). Seed treatment with the fungicide and insecticide, coated with the polymers, Florite 1127®, Solid Resin GV5®, Polyseed CF® and VermDynaseed®, did not affect the physiological quality of rice seeds. Solid Resin GV5®, Polyseed CF® and VermDynaseed® polymers were efficient at retaining thiamethoxam in the rice seeds, preventing some of the active ingredients of the insecticide from being leached through the sand columns immediately after the simulated pluvial precipitation

Principais técnicas de preparo de amostra para a determinação de resíduos de agrotóxicos em água por cromatografia líquida com detecção por arranjo de diodos e por espectrometria de massas

The determination of pesticide residues in water samples by Liquid Chromatography require sample preparation for extraction and enrichment of the analytes with the minimization of interferences to achieve adequate detection limits. The Solid Phase Extraction (SPE), Solid Phase Microextraction (SPME), Stir Bar Sorptive Extraction (SBSE) and Dispersive Liquid-Liquid Microextraction (DLLME) techniques have been widely used for extraction of pesticides in water. In this review, the principles of these sample preparation techniques associated with the analysis by Liquid Chromatography with Diode Array Detection (LC-DAD) or Mass Spectrometry (LC-MS) are described and an overview of several applications were presented and discussed