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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Determination and degradation of diazinon and malathion in soils and waters

Konrad, John Grey, January 1967 (has links)
Thesis (M.S.)--University of Wisconsin--Madison, 1967. / eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
2

Microbial interactions with Diazinon.

Ralston, Walter Jay 01 January 1967 (has links) (PDF)
No description available.
3

Selective effect of diazinon on the soil microflora with reference to the control of soil-borne pathogens.

Trela, John Michael 01 January 1967 (has links) (PDF)
No description available.
4

Metal ion promoted hydrolysis of the organophosphorus pesticide diazinon

Wyer, Martin 01 February 2008 (has links)
The chemical fate of organophosphorus pesticides is influenced by several factors, one being the chemistry of their aquatic environment. Dissolved metal ions have been shown in several instances to promote the hydrolysis of organophosphorus pesticides, with various reasons forwarded as to the intimate mechanism of metal ion promoted hydrolysis. Several postulates have suggested metal ion co-ordination of Lewis sites to be an important factor in promoting the reaction. In view of this, the study herein reports on the promoted hydrolysis of diazinon at various pH’s in the presence of several metal ions including Hg2+, Cu2+, Cd2+ and Ag+. The observed 1H and 31P NMR data indicated complexation of Cu2+ and Ag+ with diazinon through the formation of a six-membered ring (chelate), via co-ordination at both nitrogen and sulfur Lewis base sites. In contrast, NMR results with Hg2+ indicated Hg2+ ion promoted hydrolysis of diazinon through co-ordination at sulfur alone, possibly through stronger binding to the altered transition state than the reactant state. Another possibility would entail lowering of the pKa of H2O on metal complexation, thus facilitating nucleophilic attack. Electrospray ionization mass spectrometry (ESI-MS) substantiated the proposed metal ion complexation. In the case of Cu2+ and Ag+, complexation between diazinon and metal ions was observed at given m/z ratios, while subsequent MS/MS analysis of the complexed ions revealed co-ordination at both S and N sites by Cu2+ and Ag+. No complexation between diazinon and Hg2+ was observed in ESI-MS; however Hg2+ was shown to complex the hydrolytic product O,O diethyl phosphorothioic acid, presumably through sulfur. Hydrolysis of diazinon was studied at several pH’s at 22oC in the presence of Hg2+, Cu2+, Cd2+ and Ag+, by following spectrophotometrically the appearance of 2-isopropyl-6-methylpyrimidin-4-ol. Kinetic data showed Hg2+, Cu2+ and Ag+ to be extremely effective in neutral-to-mildly acidic conditions, with a reduced effect in the presence of Cd2+. Smaller rate enhancements were also observed at slightly lower pH of 4.0. Possible factors include; 1) Competing acid hydrolysis involving protonation at one heterocyclic N of diazinon (N-3). 2) The dominant nature of the HgCl2 species at pH 4.0. 3) Metal speciation. / Thesis (Master, Chemistry) -- Queen's University, 2008-01-31 13:47:24.044
5

Evaluating the Hazard of Land Applying Composted Diazinon Waste Using Earthworm Biomonitoring

Leland, Jarrod Ethan 11 September 1998 (has links)
A process for disposing of pesticide rinsewater generated from the rinsing of application equipment is being developed at Virginia Polytechnic Institute and State University. This process involves the sorption of pesticides onto an organic matrix followed by degradation in a composting environment. We are now evaluating the hazards that might be associated with land-applying composted pesticide waste. Diazinon was the first pesticide selected for evaluation, which consisted of two studies. The first used the earthworm species Eisenia foetida to evaluate the toxicity of soil amended with composted diazinon waste. The second study determined the bioavailability of delta-2-14C-diazinon and its degradation products to E. foetida in soil amended with composted delta-2-14C-diazinon. Results from the first study indicate that uncomposted diazinon sorbent and 30-day composted diazinon sorbent were toxic to E. foetida at sublethal and lethal levels. However, E. foetida exposed 60-day composted diazinon sorbent did not experience mortality or demostrate sublethal effects commonly associated with acetylcholinesterase inhibition. Earthworms exposed to diazinon that was uncomposted or composted for 30 days in the radiolabelled study experienced higher mortality than in the field study. After 30 and 60 days of composting 14C-diazinon became unextractably incorporated into organic matter and very little was mineralized. Earthworms were shown to accumulate radioactivity when exposed to soil amended with 60- day composted delta-2-14C-diazinon. The majority of this radioactivity was unextractably bound to earthworm tissue and that which was extractable contained only trace levels of delta-2-14C-diazinon. Based on the absence of toxicity in the field study and the low levels of 14C-diazinon present in earthworm tissues, 60 days of composting appears to greatly reduce the hazard that diazinon rinsate poses to E. foetida. / Master of Science
6

Toxicidad embrionaria en ratones pretratados con el pesticida organofosforado "Diazinon"

Díaz Saldívar, Patricia Susana January 2006 (has links)
Diazinon es uno de los pesticidas organofosforados de mayor uso alrededor del mundo. Al igual que otros organofosforados, ejerce su acción tóxica a través de la inhibición de la enzima acetilcolinesterasa lo cual ocasiona que la acetilcolina se acumule en los espacios presinápticos y sobre-estimule diversos tejidos y órganos -entre ellos, los músculos respiratorios- llegando a producir muerte por asfixia en casos de sobredosis. A nivel reproductivo, en mamíferos, puede afectar las gónadas masculinas, disminuyendo así la calidad espermática. Se desconocen sus efectos a nivel de gónadas femeninas y sobre la progenie. El objetivo de la presente tesis fue evaluar la toxicidad producida por el pesticida organofosforado Diazinon mediante la observación y análisis de los embriones preimplantacionales de ratón obtenidos a partir de hembras y machos tratados independientemente. Para ello, se trataron intraperitonealmente por 5 días consecutivos, cuatro grupos de diez individuos, tanto para el tratamiento paterno como materno. Tres de los grupos recibieron las dosis de 5,25, 10,5 y 21 mg/kg de peso corporal de Diazinon diluido en aceite de maíz, respectivamente; el cuarto grupo, usado como control negativo, fue tratado sólo con el vehículo. Luego de terminado el tratamiento, cada macho fue apareado semanalmente con una hembra no tratada durante 6 semanas, mientras que las hembras fueron apareadas por una sola vez con un macho no tratado. Al cuarto día de preñez todas las ratonas fueron sacrificadas para evaluar la cantidad, calidad, morfología, desarrollo y proliferación celular de los embriones preimplantacionales obtenidos. Durante el tratamiento paterno, los parámetros embrionarios resultaron afectados de forma variable a lo largo de las seis semanas de evaluación. El efecto tóxico de Diazinon fue más evidente durante las semanas 1 y 5, poniendo así en evidencia que los espermatozoides, espermátides tardías, espermatocitos tempranos y espermatogonias tipo B son los tipos celulares más sensibles al tratamiento. Durante el tratamiento materno sólo se incrementó el número de embriones retrasados y con morfología de grado 3 y 4. En ambos tratamientos se encontraron embriones con defecto en la formación del blastocele, lo que demostraría el potencial estrogénico de Diazinon sobre los embriones. Diazinon actúa de forma diferente en machos y hembras debido a las características biológicas de cada sexo y ello se ve reflejado en los resultados. En conclusión, Diazinon afecta la calidad gamética masculina y femenina, siendo este efecto heredable y evidente durante el desarrollo embrionario preimplantacional del ratón. / Diazinon is one of the most widely used organophosphate pesticides worldwide. Similar to other organophosphorates, it exerts its toxic action through the inhibition of the enzyme acetylcholinesterase, which induces acetylcholine accumulation in presynaptic spaces and thus overstimulating several tissues and organs -amongst them, the respiratory musculature- leading to death by asphyxia in case of an overdose. At the reproductive level, in mammals, Diazinon may affect the male gonads, hence decreasing sperm quality. Its effects over the female gonads and over the progeny of affected individuals are currently unknown The objective of the present thesis was to evaluate the toxicity produced by the organophosphate pesticide Diazinon thru the observation and analysis of mouse preimplantation embryos recovered from independently exposed male and female mice. In order to do that, four groups of mice each composed of ten individuals were intraperitonealy treated during 5 consecutive days, both for paternal and maternal treatments. Three of those groups received doses of 5.25, 10.5, and 21 mg/kg of body weight of Diazinon, respectively, diluted on corn oil; the fourth group, regarded as the negative control, only received the vehicle. After finishing the treatment, each treated male mouse was caged and breaded with an untreated female mouse on a weekly basis during 6 weeks, while treated female mice were breaded with untreated males only once. On the fourth day of pregnancy, all pregnant female mice were sacrificed to assess the number, quality, morphology, stage of development and cell proliferation status in recovered preimplantation embryos. During paternal treatment, the embryo parameters were affected on a variable basis along the six-week evaluation period. The toxic effect of Diazinon showed to be more evident on weeks 1 and 5, thus resulting that spermatozoa, late spermatids, early spermatocytes and type B spermatogonia are the most sensitive-to-treatment cell types. On the other hand, during maternal treatment, only the number of developmentally delayed and morphological grade 3 and 4 embryos augmented. In both treatments, embryos with defective blastocoele formation, a feature that demonstrates the estrogenic potential of Diazinon on preimplantation embryos. Diazinon acts differentially on males and females due to the biological characteristics of each gender, a fact that became reflected in our results. In conclusion, Diazinon affects the male and female gamete quality, being this effect heritable and evident during preimplantation embryo development in the mouse.
7

Toxicidad embrionaria en ratones pretratados con el pesticida organofosforado "Diazinon"

Díaz Saldívar, Patricia Susana January 2006 (has links)
Diazinon es uno de los pesticidas organofosforados de mayor uso alrededor del mundo. Al igual que otros organofosforados, ejerce su acción tóxica a través de la inhibición de la enzima acetilcolinesterasa lo cual ocasiona que la acetilcolina se acumule en los espacios presinápticos y sobre-estimule diversos tejidos y órganos -entre ellos, los músculos respiratorios- llegando a producir muerte por asfixia en casos de sobredosis. A nivel reproductivo, en mamíferos, puede afectar las gónadas masculinas, disminuyendo así la calidad espermática. Se desconocen sus efectos a nivel de gónadas femeninas y sobre la progenie. El objetivo de la presente tesis fue evaluar la toxicidad producida por el pesticida organofosforado Diazinon mediante la observación y análisis de los embriones preimplantacionales de ratón obtenidos a partir de hembras y machos tratados independientemente. Para ello, se trataron intraperitonealmente por 5 días consecutivos, cuatro grupos de diez individuos, tanto para el tratamiento paterno como materno. Tres de los grupos recibieron las dosis de 5,25, 10,5 y 21 mg/kg de peso corporal de Diazinon diluido en aceite de maíz, respectivamente; el cuarto grupo, usado como control negativo, fue tratado sólo con el vehículo. Luego de terminado el tratamiento, cada macho fue apareado semanalmente con una hembra no tratada durante 6 semanas, mientras que las hembras fueron apareadas por una sola vez con un macho no tratado. Al cuarto día de preñez todas las ratonas fueron sacrificadas para evaluar la cantidad, calidad, morfología, desarrollo y proliferación celular de los embriones preimplantacionales obtenidos. Durante el tratamiento paterno, los parámetros embrionarios resultaron afectados de forma variable a lo largo de las seis semanas de evaluación. El efecto tóxico de Diazinon fue más evidente durante las semanas 1 y 5, poniendo así en evidencia que los espermatozoides, espermátides tardías, espermatocitos tempranos y espermatogonias tipo B son los tipos celulares más sensibles al tratamiento. Durante el tratamiento materno sólo se incrementó el número de embriones retrasados y con morfología de grado 3 y 4. En ambos tratamientos se encontraron embriones con defecto en la formación del blastocele, lo que demostraría el potencial estrogénico de Diazinon sobre los embriones. Diazinon actúa de forma diferente en machos y hembras debido a las características biológicas de cada sexo y ello se ve reflejado en los resultados. En conclusión, Diazinon afecta la calidad gamética masculina y femenina, siendo este efecto heredable y evidente durante el desarrollo embrionario preimplantacional del ratón. / Diazinon is one of the most widely used organophosphate pesticides worldwide. Similar to other organophosphorates, it exerts its toxic action through the inhibition of the enzyme acetylcholinesterase, which induces acetylcholine accumulation in presynaptic spaces and thus overstimulating several tissues and organs -amongst them, the respiratory musculature- leading to death by asphyxia in case of an overdose. At the reproductive level, in mammals, Diazinon may affect the male gonads, hence decreasing sperm quality. Its effects over the female gonads and over the progeny of affected individuals are currently unknown The objective of the present thesis was to evaluate the toxicity produced by the organophosphate pesticide Diazinon thru the observation and analysis of mouse preimplantation embryos recovered from independently exposed male and female mice. In order to do that, four groups of mice each composed of ten individuals were intraperitonealy treated during 5 consecutive days, both for paternal and maternal treatments. Three of those groups received doses of 5.25, 10.5, and 21 mg/kg of body weight of Diazinon, respectively, diluted on corn oil; the fourth group, regarded as the negative control, only received the vehicle. After finishing the treatment, each treated male mouse was caged and breaded with an untreated female mouse on a weekly basis during 6 weeks, while treated female mice were breaded with untreated males only once. On the fourth day of pregnancy, all pregnant female mice were sacrificed to assess the number, quality, morphology, stage of development and cell proliferation status in recovered preimplantation embryos. During paternal treatment, the embryo parameters were affected on a variable basis along the six-week evaluation period. The toxic effect of Diazinon showed to be more evident on weeks 1 and 5, thus resulting that spermatozoa, late spermatids, early spermatocytes and type B spermatogonia are the most sensitive-to-treatment cell types. On the other hand, during maternal treatment, only the number of developmentally delayed and morphological grade 3 and 4 embryos augmented. In both treatments, embryos with defective blastocoele formation, a feature that demonstrates the estrogenic potential of Diazinon on preimplantation embryos. Diazinon acts differentially on males and females due to the biological characteristics of each gender, a fact that became reflected in our results. In conclusion, Diazinon affects the male and female gamete quality, being this effect heritable and evident during preimplantation embryo development in the mouse.
8

Sıçanlarda subletal doz ile oluşturulan akut diazinon toksisitesinde pankreas hasarının zamana göre değişimi /

Altınışık,Uğur. Özmen, Sadık. January 2007 (has links) (PDF)
Tez (Tıpta Uzmanlık) - Süleyman Demirel Üniversitesi, Tıp Fakültesi, Anesteziyoloji ve Reanimasyon Anabilim Dalı, 2007. / Bibliyografya var.
9

Influência da temperatura nas respostas aos biocidas diazinon e carbaril em Dilocarcinus pagei Stimpson, 1861 /

Lima, Alexandre Vidotto Barboza. January 2016 (has links)
Orientador: Lilian Castiglioni / Coorientador: Eduardo Alves de Almeida / Banca: Marcelo Campos / Banca: Luis Octávio Regasini / Banca: Francine Perri Venturini / Banca: Neide Aparecida Blaz / Resumo: As mudanças climáticas globais têm recebido destaque na área da toxicologia aquática em função dos efeitos que as alterações na temperatura da água podem exercer nas respostas dos organismos aquáticos aos contaminantes ambientais. A temperatura corpórea dos organismos ectotérmicos, como os crustáceos, é totalmente dependente da temperatura do ambiente, de modo que aumentos na temperatura afetam diretamente o metabolismo desses animais, acelerando as reações bioquímicas e a absorção de muitos contaminantes aquáticos no organismo. Neste trabalho foi investigado a influência de três faixas de temperatura (18, 23 e 28 °C) na toxicidade dos biocidas diazinon (organofosforado) e carbaril (carbamato) nas brânquias e no hepatopâncreas de machos e fêmeas do caranguejo de água doce Dilocarcinus pagei, utilizando como parâmetros analíticos as enzimas antioxidantes glutationa S-tranferase (GST), glutationa peroxidase (GPx), glutationa redutase (GR), glicose 6-fosfato-desidrogenase (G6PDH), níveis de peroxidação lipídica por meio da formação do malondialdeído (MDA) e os efeitos clássicos de inibição das esterases acetilcolinesterase (AChE) e carboxilesterase (CbE). As atividades enzimáticas foram analisadas por espectrofotometria e os níveis de peroxidação lipídica por cromatografia líquida de alta performance (HPLC). A exposição de fêmeas de D. pagei ao diazinon por sete dias, levou á diminuição na atividade da GPx na concentração de 10 e 100 μg L-1 a 23°C, enquanto que nas brânquias foi observado diminuição da GST apenas na concentração de 10 μg L-1 em 23 °C. Quanto aos machos, os resultados apresentaram diminuição da GST na concentração de 100 μg L-1 tanto em 18 °C quanto em 28 °C. Também foi observado diminuição na atividade da GR na maior concentração (100 μg L-1) em 18 °C no hepatopâncreas deste mesmo sexo. Nas brânquias, este grupo apresentou diminuição da GPx em 18 °C... / Abstract: Global climate change has been highlighted in the field of aquatic toxicology due to the effects that changes in water temperature can perform on the responses of aquatic organisms to environmental contaminants. The body temperature of ectothermic organisms, such as crustaceans, is totally dependent on the environment temperature, so that increases in temperature directly affect the metabolism of these animals, accelerating the biochemical reactions and the intake of many water contaminants. In this study, we investigated the influence of three temperature ranges (18, 23 and 28°C) on toxicity of biocides diazinon (organophosphate) and carbaryl (carbamate) in the gills and hepatopancreas of males and females of the freshwater crab Dilocarcinus pagei. Through the analytical parameters of the antioxidant enzymes glutathione S-transferase (GST), glutathione peroxidase (GPx), glutathione reductase (GR), glucose 6-phosphate dehydrogenase (G6PDH), levels of lipid peroxidation through the formation of malondialdehyde (MDA) and the classical inhibition of the esterases acetylcholinesterase (AChE) and carboxylesterase (CbE). We measured the enzyme activities by spectrophotometry and the levels of lipid peroxidation by high performance liquid chromatography (HPLC). The exposure of D. pagei females to diazinon for seven days resulted in decrease in GPx activity in 10 and 100 µg/L of concentration at 23°C. In the gills, we observed reduction of GST only in the concentration of 10 µg/L at 23°C. In males, the results showed decrease in GST activity in the concentration of 100 µg/L at both temperatures (18 and 28°C). We also observed decrease in GR activity at the highest concentration (100 µg/L) at 18°C in the hepatopancreas of this gender. In the gills, this group showed decrease in GPx at 18°C in a concentration of 100 μg/L and GR increased in 10 µg/L of concentration at 28°C. According to G6PDH response, we observed decrease at a ... / Doutor
10

Detection and quantitation of diazinon and chlorpyrifos : a novel GC

Hu, Xiaoyi 01 January 2002 (has links) (PDF)
An analytical method was developed for detection and quantitation of diazinon and chlorpyrifos, two widely used pesticides in local water pathway. Solid phase extraction combined with GC/MS detection with selected ion monitoring was employed. In establishing calibration curves for GC/MS analysis, it may be impractical to use isotope-labeled analogs as internal standards for all analytes in a complicated matrix. Compounds may have to be used as internal standards which could cause non-linear effects because of different response of analytes and internal standards. A novel sample introduction method, which could eliminate this negative effect of non-linearity, was proposed. Calibration data were acquired using the traditional constant volume injection method, and a new method: constant mass injection of analytes. Calibration curves by the constant mass injection method show a better linearity and y-intercept. The nonlinear effect observed with data obtained in low concentration ranges using the constant volume injection method was eliminated. The effectiveness of these curves by two methods was also tested. Better accuracy was obtained with the constant mass injection method. This constant mass injection of analytes method could be very useful in quantitative studies of a complicated sample matrix, such as those encountered in the environmental analysis of pesticides, or in the quality control analysis of medical and industrial product. In solid phase extraction, Varian Bondelute SPE C8 cartridge was selected for extraction. With the standard water sample spiked at 500 ng/L for the two analytes, the recovery for diazinon was about 50% and for chlorpyrifos about 60%. With the standard water sample at 1000 ng/L, the recovery for diazinon was about 60% and for chlorpyrifos about 70%. Among three samples from three different sampling sites, diazinon was detected and confirmed. The quantitation of diazinon was done to water sample from the Calaveras River near the Sanguetti Street crossing Stockton, California, with observed concentration 143.2 ng/L.

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