Dissertations / Theses on the topic 'Insecticide toxicology'
To see the other types of publications on this topic, follow the link: Insecticide toxicology.
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 50 dissertations / theses for your research on the topic 'Insecticide toxicology.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse dissertations / theses on a wide variety of disciplines and organise your bibliography correctly.
1
Mills, Nathan E. "Direct and indirect effects of an insecticide on Rana sphenocephala tadpoles /." free to MU campus, to others for purchase, 2002. http://wwwlib.umi.com/cr/mo/fullcit?p3052201.
Full text
2
Siu, Ka-yan Sky. "DDT as a malarial vector control method and its potential risks to human reproductive health and neonatal development." View the Table of Contents & Abstract, 2007. http://sunzi.lib.hku.hk/hkuto/record/B3847864X.
Full text
3
Rotundo, Maurício [UNESP]. "Exposição dérmica de trabalhadores a resíduos de deltametrina presentes nas plantas, na reentrada na lavoura de algodão após pulverização." Universidade Estadual Paulista (UNESP), 2007. http://hdl.handle.net/11449/98868.
Full textAbstract:
Made available in DSpace on 2014-06-11T19:29:44Z (GMT). No. of bitstreams: 0
Previous issue date: 2007-02-28Bitstream added on 2014-06-13T19:59:38Z : No. of bitstreams: 1
rotundo_m_me_ilha.pdf: 850611 bytes, checksum: 1909101afb4dae7d59c34fa46384f158 (MD5)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
A exposição dérmica de amostradores foi avaliada na reentrada em lavoura de algodão após pulverização com o inseticida deltametrina. Aos 3 minutos após a aplicação quatro pessoas vestiram um conjunto de roupas (calça, camisa e luvas), entrando e permanecendo na área tratada por 30 minutos, simulando uma amostragem de pragas. O procedimento foi repetido aos 60 e 300 minutos e aos 1, 3, e 7 dias após a aplicação. Partes do tecido, correspondentes ao local de contato com várias partes do corpo, foram recortadas e analisadas quanto à quantidade de resíduos presentes. O inseticida foi extraído das roupas com acetato de etila e a determinação quantitativa foi feita por cromatografia gasosa. As exposições foram extrapoladas para uma jornada de trabalho de oito horas. Para classificar a segurança das condições de trabalho foram estimadas a margem de segurança (MS), dose tóxica (%DT/dia), dose tolerável dérmica e o tempo de trabalho seguro. O conjunto correspondente aos antebraços/braços/mãos concentrou 61,27% dos resíduos presentes na roupa. Partes correspondentes ao peitoral, pernas, coxas e costas alcançaram 13,40; 9,33; 9,32; e 6,65% dos resíduos totais encontrados nas roupas, respectivamente. Pela análise dos dados constatou-se que o intervalo de reentrada estabelecido para o produto comercial Decis 25 CE (deltametrina) que é de 24 h está superestimado.
The objective of this work was to study the dermal exposure of workers to residues of the deltamethrin, applied in cotton. After 3 minutes of application four people dressed a group with cotton clothes (pant, shirt and gloves), entered and stayed in the treated area by 30 minutes, simulating a sampling. The procedure was repeated after 60 and 300 minutes and 1, 3, and 7 days of the application. The clothes were cut and put in plastic bags, and stored cold at -18º until analyses was performed. The analytical method consisted on the extraction of deltamethrin residues with a ethyl acetate and the quantitative determination was done by gas chromatograph. Exposure was extrapolated to a work day of 8 hours. To evaluate safety's conditions at work was estimated the Working Condition Unsafe (margin of safety - MOS <1), Poisonous Dose (%PD/day), Dermal Dose Tolerable and the estimate of Safe Work Duration (SWD). The corresponding group for the forearms/arms/hands concentrated 61.27% of present residues in the clothes. The residues found on the clothes, chest, legs, lame and back, were 13.40, 9.33, 9.32, and 6.65%, respectively. Results of deltamethrins amounts trapped on cotton clothes showed that 24h as a reentry interval for Decis 25 EC is overestimated.
4
Siu, Ka-yan Sky, and 蕭加欣. "DDT as a malarial vector control method and its potential risks to human reproductive health and neonatal development." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2007. http://hub.hku.hk/bib/B3972458X.
Full text
5
Chu, Wing Kei. "Accumulation and transformation of DDT and PCBs by Phragmites australis and Oryza sativa L." HKBU Institutional Repository, 2004. http://repository.hkbu.edu.hk/etd_ra/530.
Full text
6
Rotundo, Maurício. "Exposição dérmica de trabalhadores a resíduos de deltametrina presentes nas plantas, na reentrada na lavoura de algodão após pulverização /." Ilha Solteira : [s.n.], 2007. http://hdl.handle.net/11449/98868.
Full textAbstract:
Orientador: Geraldo PapaBanca: Sérgio Luis de Carvalho
Banca: Luiz Roberto Pimentel Trevizan
Resumo: A exposição dérmica de amostradores foi avaliada na reentrada em lavoura de algodão após pulverização com o inseticida deltametrina. Aos 3 minutos após a aplicação quatro pessoas vestiram um conjunto de roupas (calça, camisa e luvas), entrando e permanecendo na área tratada por 30 minutos, simulando uma amostragem de pragas. O procedimento foi repetido aos 60 e 300 minutos e aos 1, 3, e 7 dias após a aplicação. Partes do tecido, correspondentes ao local de contato com várias partes do corpo, foram recortadas e analisadas quanto à quantidade de resíduos presentes. O inseticida foi extraído das roupas com acetato de etila e a determinação quantitativa foi feita por cromatografia gasosa. As exposições foram extrapoladas para uma jornada de trabalho de oito horas. Para classificar a segurança das condições de trabalho foram estimadas a margem de segurança (MS), dose tóxica (%DT/dia), dose tolerável dérmica e o tempo de trabalho seguro. O conjunto correspondente aos antebraços/braços/mãos concentrou 61,27% dos resíduos presentes na roupa. Partes correspondentes ao peitoral, pernas, coxas e costas alcançaram 13,40; 9,33; 9,32; e 6,65% dos resíduos totais encontrados nas roupas, respectivamente. Pela análise dos dados constatou-se que o intervalo de reentrada estabelecido para o produto comercial Decis 25 CE (deltametrina) que é de 24 h está superestimado.
Abstract: The objective of this work was to study the dermal exposure of workers to residues of the deltamethrin, applied in cotton. After 3 minutes of application four people dressed a group with cotton clothes (pant, shirt and gloves), entered and stayed in the treated area by 30 minutes, simulating a sampling. The procedure was repeated after 60 and 300 minutes and 1, 3, and 7 days of the application. The clothes were cut and put in plastic bags, and stored cold at -18º until analyses was performed. The analytical method consisted on the extraction of deltamethrin residues with a ethyl acetate and the quantitative determination was done by gas chromatograph. Exposure was extrapolated to a work day of 8 hours. To evaluate safety's conditions at work was estimated the Working Condition Unsafe (margin of safety - MOS <1), Poisonous Dose (%PD/day), Dermal Dose Tolerable and the estimate of Safe Work Duration (SWD). The corresponding group for the forearms/arms/hands concentrated 61.27% of present residues in the clothes. The residues found on the clothes, chest, legs, lame and back, were 13.40, 9.33, 9.32, and 6.65%, respectively. Results of deltamethrins amounts trapped on cotton clothes showed that 24h as a reentry interval for Decis 25 EC is overestimated.
Mestre
7
Kharel, Kabita. "Evaluation of pyrethrin aerosol insecticide as an alternative to methyl bromide for pest control in flour mills." Thesis, Kansas State University, 2013. http://hdl.handle.net/2097/16006.
Full textAbstract:
Master of ScienceDepartment of Entomology
Frank H. Arthur
Kun Yan Zhu
Experiments were conducted to assess the effects of direct and indirect exposure scenarios, different degrees of residual flour, open and obstructed positions, and seasonal temperature variations on the efficacy of synergized pyrethrin against the red flour beetle, Tribolium castaneum (Herbst) and the confused flour beetle, Tribolium confusum Jacquelin du Val. To evaluate effects of direct and indirect exposures of T. castaneum and T. confusum eggs, larvae, pupae, or eggs to the insecticide aerosol within a flour mill, the following treatments were made to each life stage: insects treated with aerosol and transferred to treated or untreated flour, untreated insects transferred to treated flour, and insects and flour combined and treated together. Different degrees of harborage or sanitation levels were created by exposing T. confusum larvae, pupae, and adults to pyrethrin aerosol in Petri dishes containing 0, 0.1, 1, 5, and 10 g of wheat flour. Effects of pyrethrin dispersal in open and obstructed positions and seasonal temperature variations were assessed by exposing T. confusum pupae and adults in open positions and inside wooden boxes (1 m long, 20 cm wide, and 5, 10, or 20 cm high) inside experimental sheds maintained at target temperatures of 22, 27, and 32 °C. Results showed that when T. castaneum and T. confusum were directly exposed to aerosol without the flour source, or with a low amount of flour at open exposed areas, the aerosol provided good control against all life stages of T. castaneum and T. confusum. However, when insects were indirectly exposed (treated together with flour or untreated insects were transferred to treated flour), or treated together with deeper flour amounts, and exposed inside the boxes, the efficacy was greatly reduced. Eggs and pupae of both the species were more susceptible compared to larvae and adults. Additionally, the moribund adults initially observed in indirect exposure treatments, or at the deeper flour depth and exposure positions insides the boxes, were better able to recover. Generally, temperatures in the range of 22-32 °C had no significant effects on overall efficacy of pyrethrin aerosol.
8
Chan, Kit Yan. "Dietary exposure, human body loadings, and health risk assessment of persistent organic pollutants at two major electronic waste recycling sites in China." HKBU Institutional Repository, 2008. http://repository.hkbu.edu.hk/etd_ra/943.
Full text
9
Ludington, Timothy Shane Ludington. "The degree of impairment of foraging in crayfish (Orconectes virilis) due to insecticide exposure is dependent upon turbulence dispersion." Bowling Green State University / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1466173210.
Full text
10
Corcellas, i. Carramiñana Cayo-Eduard. "Estudi dels insecticides Piretroides en mostres biològiques i humanes." Doctoral thesis, Universitat de Barcelona, 2017. http://hdl.handle.net/10803/462848.
Full textAbstract:
Aquesta tesi pretén donar una visió general del comportament dels piretroides en el medi ambient i, concretament en la biota salvatge. A més, com a conseqüència directa d’això, també avalua l’exposició humana a aquests insecticides.
Els piretroides són uns insecticides emprats molt comunament. El seu ús abasta des d’usos agraris i ramaders fins a domèstics. També s’han emprat sovint en control de plagues i Salut Pública, com ara amb el control de mosquits vectors de malalties com la malària o el dengue. Per últim, l’ús dels piretroides sobre els humans tampoc no és estrany, ja que les fórmules més habituals de locions anti- polls i contra la sarna, entre d’altres, contenen piretroides com a principis actius.
Aquests insecticides són sintètics o semi-sintètics. Deriven d’uns extractes naturals de flors de diferents espècies de Chrisantemum. Aquests extractes contenen piretrines que són ésters de l’àcid crisantèmic. Els piretroides, són, també, ésters d’aquest àcid que solen estar funcionalitzats. Segons si contenen un grup ciano en la posició alfa’ de l’àcid, es distingeixen els piretroides tipus I (que no contenen el grup ciano) i els de tipus II (que sí que el tenen). Aquestes molècules, són molècules amb 2 o 3 centres quirals, raó per la qual la isomeria d’aquests també és un tema important a tractar.
Durant la tesi es va desenvolupar un mètode de determinació enantioselectiu per a 6 piretroides. Fins al inici de la tesi cap mètode quiral de la bibliografia era capaç de separar tots els enantiòmers d’un piretroide. El mètode desenvolupat demostrà l’eficàcia en separar els 4 isòmers de la tetrametrina. Per contra, amb la resta de piretroides del mètode (bifentrina, ciflutrina, cihalotrina, cipermetrina i peremetrina) només els isòmers cis es podien separar enantiomèricament, mentre que els trans no es podien discriminar. A més d’aquesta metodologia, es millorà la metodologia preexistent de quantificació de piretroides, la qual fou capaç, al final de la tesi, de determinar 19 piretroides i un pesticida organofosforat (clorpirifós) en una sola anàlisi.
Un cop es tenia metodologia adequada, es mostrejar fauna salvatge. Es dividí el tipus de fauna segons el medi que habiten les espècies, a saber, medi terrestre i medi aquàtic. Les espècies de medi terrestre que es van incloure en el estudi foren aus i grans mamífers de l’Antàrtida. De les aus es mostrejaren ous. Concretament, s’analitzaren ous infèrtils d’aus del Parc Natural de Doñana. El 96% de les mostres donaren positiu a la presència de piretroides. A més de l’anàlisi de piretroides s’analitzaren els delta15N i el
delta14C, amb la finalitat de comprovar si els piretroides eren biomagnificables en la xarxa tròfica. Tot i que els resultats de isòtops estables no foren concloents, tot semblà indicar que l’exposició als piretroides venia donada per la dieta, tot i que no es biomagnificaven. En mostres de mamífers de l’Antàrtic no es trobaren nivells de piretroides detectables, la qual cosa indicà que aquests insecticides no es transporten llargues distàncies.
Del medí aquàtic s’analitzaren peixos de riu i dofins. El 100% de les mostres presentà nivells quantificables de piretroides. Els peixos mostraren que l’exposició de piretroides ha d’estar relacionada amb quelcom més que no pas el medi físic ja que individus del mateix punt de presa de mostra presentaven perfils de piretroides diferents, és a dir, que la proporció d’un piretroide respecte d’un altre era diferent segon el individu analitzat. Això podia venir donat a una metabolització selectiva d’uns piretroides o a que l’exposició fos via dieta i els animals, que pertanyien a espècies diferents, tinguessin diferents hàbits alimenticis. Pel que fa a dofins, es va trobar que tant dofins brasilers com espanyols presentaven nivells de piretroides tot i que els primers solien presentar més nivells de cipermetrina i permetrina mentre que els segons de cipermetrina i tetrametrina. També es va demostrar la transferència materna com un possible problema toxicològic per als fetus i els lactants. Finalment, es va comprovar la distribució dels piretroides en diferents teixits i es va arribar a la conclusió que el teixit adipós és on més piretroides s’acumulen, tot i que, segurament gràcies a la unió amb diferents proteïnes, en teixits magres també s’hi trobaven nivells. Amb això es preferí per a mostrejos posteriors el fetge com a matriu a analitzar o, en cas de individus vius, el teixit adipós superficial.
Respecte dels humans, es comprovà que la població general està exposada als piretroides a nivells relativament baixos. Els estudis es van fer en poblacions de Brasil, Colòmbia i Barcelona. Amb tot, donats els resultats, s’optà per aconsellar un millor control dels nivells de piretroides en llets maternes, sobretot de poblacions sobre-exposades, i una revisió dels valors de ingesta acceptables de piretroide en el cas de infants i lactants.The present Thesis is about pyrethroid insecticides. They are very used in agrarian, veterinarian and domestic environments. Besides, they are used in Public Health in order to control mosquito vectors of diseases such as malaria and dengue. They are chiral molecules, thus isomeric characteristics are important in their environmental behavior and toxicology. In this thesis, a new method for enantiomeric discrimination of 6 pyrethroids was developed. For the first time a method was able to separate all enantiomers of one pyrethorid, in this case, tetramethrin. Besides, the method was able to differentiate cis enantiomers of bifenthrin, cyfluthrin, cyhalothrin, cypermethrin and permethrin. Pyrethorids were evaluated in unfertile wild bird egg samples, Antarctic mammals, river fishes and dolphins. In 96% of bird eggs residues of pyrethroids were observed. In 100% of all the rest of matrices presented quantifiable levels of pyrethroids except for Antarctic mammal samples. First way of exposure to pyrethroids for these wild species seemed to be diet. However, no biomagnification was described. Long distance transport was discarded since Antarctic samples did not present levels of pyrethrids. Pyrethroids were mostly accumulated in lipid tissues, such as dolphin blubber. The best matrix to future monitoring was described as liver samples, even when for living individuals, superficial blubber sample could be used. Cis isomer of pyrethroids were more bioaccumulated than trans, except in the case of tetramethrin. In this last case, commercial mixtures, which are enhanced in trans isomer, could explain this observation. For the rest of pyrethroids, cis isomer was enhanced because of the preference of trans isomer in the isomer-selective metabolization of most of organisms. Regarding human exposure, breast milk samples from Brazil, Colombia and Spain were analyzed. All samples were positive in the pyrethroid determination analyses. Even when levels in general population seemed to be save, Acceptable Daily Intake values should be reconsidered for breastfed children.
11
Distel, Christopher A. "Effects of an Insecticide on Competition in Anurans: Could Pesticide-Induced Competitive Exclusion be a Mechanism for Amphibian Declines?" Miami University / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=miami1280363910.
Full text
12
Nigond, Jacques. "Intoxications aigues par les insecticides organophosphorés : à propos de 50 cas." Montpellier 1, 1988. http://www.theses.fr/1988MON11205.
Full text
13
Esquivel, Palma Carlos Josue. "TOXICOLOGICAL INTERACTIONS BETWEEN THIAMETHOXAM, APHIDS, AND PREDATORY NATURAL ENEMIES." The Ohio State University, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=osu1574435608424832.
Full text
14
Morodi, Thabiso John. "To spray or not to spray with DDT to control malaria : a case study in environmental ethics." Thesis, Stellenbosch : Stellenbosch University, 2003. http://hdl.handle.net/10019.1/53698.
Full textAbstract:
Thesis (MPhil)--Stellenbosch University, 2003.Full text to be digitised and attached to bibliographic record.
ENGLISH ABSTRACT: This assignment is devoted to an in depth analysis of the pro- and the contra-positions in the long-standing and costly debate about the question whether to spray with DDT or not in the fight against malaria. I argue that the dilemma whether or not to spray with DDT is born out of a political agenda, hype, exaggeration and misinformation of the first order. Radical environmentalists appear to insist that DDT is a principal contributor of environmental degradation, and the major cause of death amongst wildlife and humans. Worse still, many Western people seem to be under the impression that mosquitoes cannot cause so much human misery as purported, and that malaria is caused by some kind of plant form of life, or even a virus. The proponents of DDT, on the other hand, appear to be convinced that DDT is a saviour of humankind, and argue that the horrors associated with DDT are exaggerated and baseless, as they are not backed by scientific inquiry. Proponents of DDT also believe that anything that is overused may kill, even ordinary table salt. Inthis assignment, both of these positions are scrutinized. On the basis of an historical overview in Chapter I of the history of the use of DDT, and the emergence of the debate about DDT in the wake of Rachel Carson's Silent Spring (1962), Chapter 2 is devoted to an evaluation of seven basic arguments against the use of DDT, while in Chapter 3 six arguments for the use of DDT are weighed. In Chapter 4 a resolution of the dilemma is proposed in which a case is made for a limited use of DDT only for indoor spraying of huts and houses against malaria mosquitoes until such time as a less dangerous alternative for DDT is found that can be used as effectively in the fight against malaria. As such, this case is informed by the strong moral conviction that we cannot allow poor people of colour to die because of a general ban on the use of DDT. Further research on this ethical debate is encouraged.
AFRIKAANSE OPSOMMING: Hierdie werkstuk is toegespits op 'n in-diepte analise van die pro- en kontra-posisies in die voortslepende, asook duur debat oor die gebruik van DDT al dan nie in die bekamping van Malaria. Ek argumenteer dat die dilemma rondom die vraag of DDT gebruik moet word of nie, aangewakker word deur politieke agendas, sensasie, oordrywing en foutiewe informasie van die eerste orde. Radikale omgewingsgesindes dring oënskynlik daarop aan dat die gebruik van DDT 'n hoof-oorsaak is van die agteruitgang van die omgewing, asook 'n primêre oorsaak van dood onder wild en mense. Erger nog, dit wil voorkom of heelwat Westerse mense onder die indruk is dat muskiete nie werklik soveel menslike lyding kan veroorsaak as wat voorgegee word nie, en dat malaria eerder veroorsaak word deur 'n sekere soort plantvorm van lewe, of selfs deur 'n virus. Die voorstaanders van DDT, aan die ander kant, is klaarblyklik oortuig dat DDT 'n redder van die mensdom is, en argumenteer dat die gruwels wat geassosieer word met DDT 'n grondelose oordrywing is, aangesien dit nie deur wetenskaplike ondersoek gesteun word nie. Voorstaanders van DDT glo verder dat enige stof wat in oormaat gebruik word, die dood kan veroorsaak, selfs gewone tafelsout. In hierdie werkstuk word albei hierdie posisies krities bestudeer en bespreek. Op grond van 'n historiese oorsig in Hoofstuk 1 oor die gebruik van DDT, en die ontstaan van die debat oor DDT na aanleiding van Rachel Carson se Silent Spring (1962), word Hoofstuk: 2 gewy aan 'n evaluasie van sewe basiese argumente teen die gebruik van DDT, terwyl in Hoofstuk 3 ses argumente vir die gebruik van DDT oorweeg word. In Hoofstuk 4 word 'n voorstel gemaak vir die resolusie van die dilemma deur 'n saak uit te maak vir die beperkte gebruik van DDT, nl. slegs vir binneshuise gebruik in hutte en huise teen malaria-muskiete tot tyd en wyl 'n minder gevaarlike alternatief vir DDT gevind word wat net so effektief sal wees in die stryd teen malaria. As sulks word hierdie studie gerugsteun deur die sterk morele oortuiging dat ons nie kan toelaat dat mense van kleur sterf as gevolg van 'n algemene verbod op die gebruik van DDT nie. Verdere navorsing oor hierdie etiese debat word aangemoedig.
15
Nassr, Azize Cristina Capelli. "Desenvolvimento reprodutivo de ratos machos expostos ao fenvalerato in utero e lactação." [s.n.], 2005. http://repositorio.unicamp.br/jspui/handle/REPOSIP/318041.
Full textAbstract:
Orientador: Wilma De Grava KempinasDissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia
Made available in DSpace on 2018-08-05T10:14:11Z (GMT). No. of bitstreams: 1 Nassr_AzizeCristinaCapelli_M.pdf: 10674778 bytes, checksum: 6e73e575f70e9f4c4cdd81eb7eac3586 (MD5) Previous issue date: 2005
Resumo: o fenvalerato é um inseticida piretróide sintético usado na agricultura, pecuária e no controle de insetos domésticos, e seus efeitos reprodutivos são pouco conhecidos. Algunsestudos têm proposto que o fenvaleratoseja um desregulador endócrino,atuando como um estrógeno ambiental. Estudos realizados com ratos adultos expostos a determinados piretróides mostraram a redução do número de espermatozóides e das concentrações plasmáticas de testosterona. Sabendo-se que o sistema reprodutor masculino de ratos é mais sensível ao efeito de substâncias tóxicas durante as fases fetal e neonatal, o objetivo deste trabalho foi avaliar os possíveis efeitos tardios sobre o desenvolvimento reprodutivo na pré-puberdade (40 dias de idade), puberdade (60 dias) e maturidadesexual (90 dias), em ratos machos cujas mães foram expostas ao fenvalerato durante a prenhez e lactação. Adicionalmente,investigou-seo comportamentosexual, a fertilidadedos ratos adultos,a transferênciado fenvaleratodas mães para a prole,e a sua persistência no organismo dos descendentes machos. Para este estudo ratas prenhes (n=8) foram tratadas com fenvalerato técnico (96% de pureza), na dose diária de 40 mg/Kg, do 12° dia de prenhez até o final da lactação (período crítico de diferenciação do sistema reprodutor masculino da prole). Ratas controles (n=8) receberam óleo de milho (veículo), nas mesmas condições experimentais. O desenvolvimento reprodutivo foi avaliado através da idade da descida testiculare da separação prepucial,pesos dos órgãos reprodutores, concentração plasmática de testosterona, contagem de células germinativas no testículo e epidídimo, morfologia espermática, estudo do processo espermatogênico, número de células de Sertoli, do diâmetro dos túbulos seminíferos e altura de epitélio germinativo. Tambémfo~m avaliados o comportamentosexual e a fertilidadedos ratos adultos após acasalamentos naturais. A quantificação de resíduos de fenvalerato foi realizada por Cromatografia Líquida de Alta Precisão (CLAP) em amostras de órgãos e tecidos das mães, fetos e filhotes. Os resultados da quantificação de fenvalerato revelaram que o piretróide foi transferido das mães para os fetos, pela placenta, e para os filhotes, pelo leito matemo, respectivamente. O piretróide permaneceu no organismo dos filhotes até, pelo menos, 40 dias de idade, com destaque para o testículo e epidídimo. A exposição in utero e lactacional ao fenvalerato foi tóxica para o testículo, conforme mostrado pela diminuição dos pesos deste órgão nos grupos tratados e pela redução da produção espermática na puberdade, sem que tenha havido depleção androgênica ou diminuição da população de células de Sertoli. Os estudos morfológicos e morfométricos não mostraram danos sobre o aspecto histológico do testículo e o processo espermatogênico, sugerindo a ação do fenvalerato sobre a formação dos cordões seminíferos nos testículos fetais. Na idade adulta houve aumento significativo do peso da vesícula seminal e do número de ejaculações, embora os resultados dos testes de fertilidade tenham sido semelhantes entre os grupos controle e tratado. Esses achados podem ter sido uma conseqüência tardia de um desequilíbrio neuroendócrino durante o período crítico de diferenciação do sistema reprodutor masculino, quando ocorreu a exposição ao fenvalerato. Concluiu-se que o fenvalerato, diluído em óleo de milho, na dose de 40 mg/Kg, administrado para ratas do 12°. dia de prenhez até o final da lactação, foi transferido pela placenta e pelo leite matemo, provocando efeitos tardios no desenvolvimento reprodutivo da prole masculina
Abstract: Fenvalerate is a synthetic pyrethroid insecticide used in agriculture, cattle raising and in the control of domestic insects, and its reproductive effects are little-known.Some studies already have proposed that fenvalerate is an endocrine disruptor, acting as an environmentalestrogen. Studies done with rats exposed to some pyrethroids showed reduction of sperm number and plasmatic testosterone concentration. Knowingthat the male reproductive system of rats is more sensitive to the effects of toxic substances during fetal and neonatal phases, the objective of this work was to evaluate the possible Iate effects on the reproductive development at pre-puberty (aged 40 days), puberty (aged 60 days) and sexual maturity(aged 90 days) in male rats whose mothers were exposed to fenvalerate during gestation and lactation. Additionally,sexual behavior, fertilityof adult rats, transference of fenvalerate from the mothers to the offspringand its persistence in the organism of the male descendents were investigated. For this study pregnant rats (n=8) were treated with technical fenvalerate (96% purity), in the dose of 40 mglKg, from gestational day 12 until the end of lactation (critical period for differentiation of the male reproductive system of the offspring). Control rats (n=8) received com oil (vehicle), irí the same experimental conditions. The reproductive development was evaluated through of the age when testicular descent and preputial separation occurred, weight of reproductive organs, plasmatictestosterone levels, numbers of germ cells in the testis and epididymis and sperm morphology. The spermatogenic process, the number of Sertoli cells, seminiferous tubule diameter and height of the germinative epithelium were also evaluated. The sexual behavior and fertilityof adult rats were also evaluated by natural matings. Fenvalerate -residues were quantified using High Performance Liquid Chromatography (HPLC)in samples of organs and tissues of mothers,fetuses and pups. The results of the fenvalerate quantification revealed that the pyrethroid was transferred from the mothersto the fetuses through the placenta, and to the pups by maternal milk, respectively. The pyrethroid remained in the organism of the pups until at least 40 days of age, especially in the testis and epididymis. In utero and lactational exposure to fenvalerate was toxic for the testis, as shown by the diminished weight of this organ in the treated groups and reduction of the sperm production at puberty, without androgen depletion or decrease of the Sertoli cell population. The morphological and morphometrical studies did not show injuries in the histological aspect of the testis or the spermatogenic process, suggesting the action of fenvalerate on the formation of seminiferous cords in the fetal testicJe. At adult age there was a significant increase of the seminal vesicJe weight and in the number of ejaculations, although the fertilitytest results were similarbetween control and treated groups. These effects can be a Iate consequence of a neuroendocrinedysregulationduringthe critical period of differentiation of the male reproductive system, when the exposure to fenvalerate occurred. It was concluded that fenvalerate, diluted in com oil at the dose of 40 mg/Kg, administered to rats from the gestational day 12 until the end of lactation was transferred through the placenta and milk, provoking Iate effects in the reproductive development of the male offspring
Mestrado
Biologia Celular
Mestre em Biologia Celular e Estrutural
16
Broderick, Mark Philip. "The toxicology and neurotoxicity of selected pyrethroid insecticides in Spodoptera littoralis (Boisd.)." Thesis, University of Portsmouth, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.304265.
Full text
17
Hambleton, Faith Ann (Faith Ann Elizabeth). "Effect of pH on the Persistence and Toxicity of Cyfluthrin to Chironomus Tentans." Thesis, University of North Texas, 1992. https://digital.library.unt.edu/ark:/67531/metadc935772/.
Full textAbstract:
The effect of pH upon the aquatic toxicity of cyfluthrin was determined in 48 h static acute toxicity tests using 2nd instar Chironomus tentans larvae. Tests were conducted in both dechlorinated tap water and lake water of pH 8.0, 7.2, and 6.6. After 48 h, immobilized and dead larvae were removed and replaced with 2nd instar larvae to assess the persistence of toxicity. Midges were cultured in water adjusted to the pH values used in testing. Toxicity if cyfluthrin varied inversely with pH. An increase in the pH of tap water by 2 units resulted in a 2-decrease in toxicity. Toxicity of cyfluthrin also varied between tap and lake water of the same pH. EC50 values in lake water were approximately 2-3 times lower than those in tap water. Toxicity in the lake water and tap water at every pH tested was also significantly different when regression line elevations were compared. Natural waters amended with cyfluthrin were consistently more toxi to the chironomids than tap water of the same pH. Persistence of cyfluthrin at low pH also influenced chironomid behavior. Recovery of normal behavior generally began within 24 h at pH 8.0 At pH 6.0, recovery did not begin until one week after dosing. The persistence of cyfluthrin also varied with pH. Averaged across all concentrations, 30% of the initial dose remained in tap water (pH 8.0) after 48 h, compared with 45% (pH 7.2), and 75 % (pH 6.6).
18
Dubrana, Leslie. "Modèles poisson zèbre de l’intoxication aux organophosphorés cholinergiques et neuropathiques et évaluation de l’efficacité d’antidotes." Thesis, Bordeaux, 2020. http://www.theses.fr/2020BORD0187.
Full textAbstract:
Les organophosphorés (OPs) sont des composés organiques largement utilisés en tant que pesticides, plastifiants ou retardateurs de flamme et éventuellement comme armes chimiques. Ils sont responsables de plusieurs milliers de décès chaque année ainsi que de l’induction de pathologies neurologiques invalidantes et représentent de ce fait un sérieux problème de santé publique et de toxicité environnementale. Les OPs interfèrent avec l'activité d’estérases importantes pour la dégradation de certaines molécules actives au sein des organismes. La plus étudiée est l'acétylcholinestérase (AChE) qui hydrolyse l’acétylcholine. Ce neurotransmetteur est essentiel dans la transmission synaptique cholinergique de l'influx nerveux au niveau périphérique et au niveau du système nerveux central (SNC). La toxicité aiguë des OPs est liée à l’inhibition de l’AChE qui génère un syndrome cholinergique et qui induit des paralysies, des atteintes pulmonaires, vasculaires, mais aussi des convulsions, pouvant mener à la mort. Les OPs responsables de ce syndrome sont appelés OPs cholinergiques. Le traitement actuel de référence n’étant pas suffisamment efficace, il est nécessaire de trouver de nouveaux antidotes pour contrecarrer les effets de ces toxiques, en particulier au niveau du SNC, du fait de leur difficulté à franchir la barrière hémato-encéphalique. Dans ce contexte, de nombreuses nouvelles molécules doivent être évaluées pour leur bénéfice thérapeutique. Par ailleurs, certains OPs sont inducteurs d’une dégénérescence distale de certains axones des systèmes nerveux périphérique et central. Cette pathologie se développe plusieurs semaines après l'exposition et est dénommée neuropathie retardée induite par les organophosphorés (organosphosphorous-induced delayed neuropathy, OPIDN). Ces OPs neuropathiques peuvent cibler une enzyme appelée « neuropathy target esterase » (NTE/PNPLA6) mais leur mécanisme d’action n’est toujours pas élucidé et est controversé. Le poisson zèbre est un modèle reconnu qui présente de nombreux avantages pour l’expérimentation in vivo, en particulier aux stades précoces de son développement. Les travaux réalisés ont permis de mettre en place une stratégie innovante pour évaluer les effets de l’intoxication aux OPs cholinergiques et neuropathiques et pour rechercher de nouveaux antidotes par utilisation de l’éleuthéro-embryon de poisson zèbre. Cette méthodologie mêle analyses biochimiques et mise en œuvre de test locomoteurs novateurs. Les résultats obtenus apportent un nouveau système d’évaluation in vivo de l’efficacité d'antidotes pour l'empoisonnement aux OPs cholinergiques et de nouveaux éléments clés du mécanisme d’action des OPs neuropathiquesOrganophosphates (OPs) are organic compounds used as pesticides, plasticizers, flame-retardants or chemical warfare nerve agent. They are responsible for several thousand deaths each year as well as induction of pathologies of the nervous system. Therefore, they represent a serious problem of public health and environmental toxicity. OPs interfere with important esterase activities for the degradation of active molecules in organisms. The most studied is acetylcholinesterase (AChE) which hydrolyses acetylcholine. This neurotransmitter is essential in the cholinergic synaptic transmission of nerve impulses in the peripheral and central nervous system (CNS). The acute toxicity of OPs is linked to the inhibition of AChE which generates a cholinergic syndrome. This syndrome induces paralysis, pulmonary and vascular damage, but also seizures, which can lead to death. The OPs responsible for this syndrome are called cholinergic OPs. As the current standard treatment is not sufficiently effective, it is necessary to find new antidotes to counteract the effects of these toxins, in particular on the CNS, due to their difficulty in crossing the blood-brain barrier. In this context, many new molecules must be evaluated for their therapeutic benefit. Moreover, certain OPs induce a distal degeneration of axons localised in the peripheral and central nervous systems. This pathology evolves several weeks after exposure and is named organophosphate-induced delayed neuropathy (OPIDN). These neuropathic OPs can target an enzyme called neuropathy target esterase (NTE / PNPLA6) but their mechanism of action is still unclear and controversial. Zebrafish is a recognized model with many advantages for in vivo experimentation, especially in the early stages of its development. This work develop an innovative strategy to assess the effects of cholinergic and neuropathic OPs intoxication and to search new antidotes using the zebrafish eleuthero-embryo. This methodology combines biochemical analysis and innovative locomotor tests. The results obtained provide a new system for in vivo evaluation of the antidote efficacy for cholinergic OP poisoning and new key events of the neuropathic OP mechanism of action
19
Valente, Nuno Ilídio Pereira. "Análise de pesticidas organofosforados em toxicologia forense." Master's thesis, Universidade de Aveiro, 2012. http://hdl.handle.net/10773/10150.
Full textAbstract:
Mestrado em Química - Química Analítica e QualidadeOs pesticidas são substâncias destinadas a prevenir, destruir ou controlar pragas. No entanto, estes produtos são também responsáveis por intoxicações em seres humanos. Em Portugal, mais de metade das intoxicações voluntárias com pesticidas envolvem inseticidas organofosforados (IOFs). Neste trabalho, pretendeu-se desenvolver e validar um conjunto de metodologias para a determinação analítica de dez IOFs, nomeadamente, clorfenvinfos, clorpirifos, diazinão, dimetoato, fentião, fosalona, malatião, paratião, pirimifos-metilo e quinalfos, em amostras de sangue total e de conteúdo gástrico, tendo em vista a introdução das mesmas na rotina pericial do Serviço de Toxicologia Forense da Delegação do Norte do Instituto Nacional de Medicina Legal e Ciências Forenses, I.P. (STF-N). Foram testados métodos de extração de IOFs com Extração em Fase Sólida (SPE) em amostras de sangue com colunas Oasis® HLB e Sep-Pak® C18 e com separação e deteção por GC-ECD e GC-MS. O método de extração com colunas Sep-Pak® C18 foi selecionado, uma vez que no final do processo de extração e análise foram gerados sinais cinco vezes superiores aos obtidos após extração com as outras colunas de SPE, e mostrou ser seletivo para isolamento dos analitos e do padrão interno (etião) em amostras de sangue postmortem. Foram preparadas curvas de calibração entre 50 e 5000 ng/mL, utilizando modelos de regressão linear ponderada. Devido à sensibilidade mais baixa do detetor, não foi possível definir uma gama de trabalho para o fentião por GC-ECD, enquanto para o pirimifos-metilo esta foi estabelecida entre 500 e 5000 ng/mL. O limite de quantificação foi 50 ng/mL para todos os analitos, à exceção do pirimifos-metilo por GC-ECD (500 ng/mL). A eficiência de extração média situou-se entre os 72 e os 102%. Após testes com Extração Líquido-Líquido (LLE) e/ou SPE, o procedimento adotado para rastreio/confirmação qualitativa de IOFs em amostras de conteúdo gástrico, consistiu num passo de LLE com éter dietílico, evaporação do solvente e retoma do extrato em acetonitrilo, seguido de SPE com colunas Sep-Pak® C18 e da análise por GC-MS ou por GC-ECD. Obtiveram-se eficiências de extração médias entre 40 e 50% e limites de deteção de 10 μg/mL para todos os IOFs, exceto para o fentião por GC-ECD. Os métodos desenvolvidos foram considerados robustos e adequados ao propósito, tendo sido já adotados na rotina do laboratório do STF-N.
Pesticides are substances intended to prevent, destroy and control plagues. However, these products are also responsible for intoxications in humans. In Portugal, more than half of pesticide intoxications involve organophosphorus insecticides (OPs). In this thesis we intended to develop and validate methodologies for the determination of ten OPs, namely, chlorfenvinphos, chlorpyrifos, diazinon, dimethoate, fenthion, phosalone, malathion, parathion, pyrimiphos-methyl and quinalphos, in whole blood and gastric content samples, aimed at being included in routine procedures of Forensic Toxicology Laboratory of North Delegation of National Institute of Legal Medicine and Forensic Sciences (FTL-N). In blood, were tested three procedures of Solid Phase Extraction (SPE) for OPs with Oasis® HLB and Sep-Pak® C18 cartridges, followed by GC-ECD and GC-MS analysis. The Sep-Pak® C18 cartridges extraction procedure was selected because the samples prepared using that SPE cartridges generated signals 5 times higher than those obtained with the two different Oasis® HLB cartridges. The method was shown to be selective for the isolation of selected OPs as well as the internal standard (ethion) in postmortem blood samples. Calibration curves Were prepared between 50 and 5000 ng/mL using weighted linear regression models. Due to the lower sensitivity of the detector it was not possible to establish a working range for fenthion by GC-ECD, whereas for pirimiphos-methyl it was set between 500 and 5000 ng/mL. The limit of quantification was 50 ng/mL for all analytes, except for pirimiphos-methyl by GC-ECD analysis (500 ng/mL). The average extraction efficiency was obtained between 72 and 102%. After tests with Liquid-Liquid Extraction (LLE) and/or SPE, the procedure adopted for detection and qualitative confirmation of OPs in gastric content samples consisted in LLE with diethyl ether, solvent evaporation, recovery of the extract with acetonitrile, and SPE with Sep-Pak® C18 cartridges, followed by GC-ECD and GC-MS analysis. Average extraction efficiencies 40 and 50%, and detection limits of 10 μg/mL were obtained by GC-ECD, except for fenthion. The developed methods were considered robust and fit for the purpose, and were already adopted in routine analysis of FTL-N.
20
Roux, Christine. "Toxicologie environnementale d'un insecticide : études autoradiographiques de la distribution de la radioactivité chez plusieurs espèces animales traitées par la 14C-deltaméthrine." Toulouse, INPT, 1990. http://www.theses.fr/1990INPT018A.
Full textAbstract:
Le devenir de la #1#4c-deltamethrine, insecticide pyrethrinoide, a ete etudie par autoradiographie macroscopique chez plusieurs especes animales: mammiferes, oiseaux, poissons et insectes. Ce travail avait pour but d'observer des differences de distribution qui pourraient expliquer la toxicite selective de cet insecticide. La repartition de l'isotope est comparable chez les diverses especes, les plus fortes activites sont retrouvees dans le foie et le rein. Une faible activite persistant pendant au moins 8 jours est enregistree dans les graisses chez le rat et la caille. L'etude de la distribution perinatale chez le rat a mis en evidence des traces de marquage dans les organes du ftus et du nouveau-ne. L'elimination de la radioactivite dans les ufs de caille est faible et peu persistante, elle interesse principalement le vitellus. La radioactivite est assez rapidement eliminee par voie urinaire et par voies biliaire et fecale. Le systeme nerveux central n'est pratiquement pas marque. On note cependant des traces d'isotope dans cette structure chez la truite. La deltamethrine ou ses metabolites ne franchissent que tres faiblement les barrieres hematomeningee et placentaire et ne sont elimines qu'a l'etat de traces dans le lait. Chez les oiseaux, l'excretion dans les ufs s'opere dans les 24 heures qui suivent l'administration mais il s'agit d'un processus mineur. A partir d'autoradiogrammes de caille, une approche de l'evaluation quantitative de la radioactivite a ete effectuee grace a une station d'analyse d'images. En utilisant une gamme d'etalonnage, il a ete possible de mesurer des concentrations d'equivalent de produit parental dans les principaux organes de caille
21
Pitti, caballero Javier ernesto. "Nanoencapsulation d’un agent synergisant chimique, la deltaméthrine pour potentialiser l’effet d’un insecticide, l’indoxacarbe contre les insectes nuisibles." Thesis, Angers, 2019. http://www.theses.fr/2019ANGE0005.
Full textAbstract:
L’utilisation non raisonnée d’insecticides a des conséquences sur l’environnement et la santé humaine mais aussi sur le développement de résistances chez les insectes nuisibles. Dans ce contexte, ce travail de thèse porte sur le développement d'une technique de nanoencapsulation d'un agent synergisant chimique, la deltaméthrine (pyréthrinoide), associé un pro-insecticide l’indoxacarbe (oxadiazine). Sur la base d’études in vitro sur cellules neurosecrétrices de blattes (Periplaneta americana), une action synergique entre la deltaméthrine et le DCJW (métabolite actif de l’indoxacarbe) a été démontrée via un mécanisme intracellulaire original dépendant du calcium. Des études toxicologiques in vivo sur des blattes adultes ont permis de confirmer l’effet synergique entre la deltaméthrine et l’indoxacarbe. Pour optimiser la formulation de l’association de ces composés, des nanocapsules lipidiques contenant la deltaméthrine utilisée comme agent synergisant ont été produites. Les études de toxicité sur blattes ont permis de déterminer les doses effectives les plus faibles de l’association deltaméthrine nanoencapsulée/indoxacarbe et d’obtenir une optimisation de l’effet synergique avec la deltaméthrine nanoencapsulée. Cet effet synergique est plus important que celui du piperonyl butoxyde, composé utilisé dans les formulations d'insecticides classiques. Les résultats indiquent que la deltaméthrine, protégée des estérases par la nanoencapsulation, permet d’optimiser l’efficacité du traitement tout en réduisant les doses d’indoxacarbe. Cette nouvelle stratégie est une première étape dans le développement d'une formulation phytosanitaire efficace contre les insectes nuisiblesThe over-use of pesticides has represented a concern not only for its consequences against the environment but also for the increase in resistance mechanisms in pest insects. In this context, our research project is focused on the development of a nanoencapsulation technique of a deltamethrin (pyrethroid), used as synergistic agent, combined with a pro-insecticide indoxacarb (oxadiazine). Based on in vitro studies performed on cockroach (Periplaneta americana) neurosecretory cells, synergistic effect between deltamethrin and DCJW (active metabolite of indoxacarb) has been characterized, occurring through an original calcium-dependent intracellular mechanism. In vivo toxicological studies on adult cockroaches have confirmed these previous results. To optimize the formulation including the synergistic agent and indoxacarb, lipid nanocapsules (LNCs) containing deltamethrin have been developed. It has been possible to determine the lower effective doses of LNC-deltamethrin/indoxacarb mixture producing the synergistic effect in whole insects. The synergism obtained is more important than that of obtained with piperonil butoxide (PBO), the well-known synergist used in classical insecticide formulations. The results also indicate that LNC-deltamethrin, protected from esterase-induced detoxification enhances the toxicity of indoxacarb while reducing doses. This novel strategy is a first step for the development of a novel formulation more efficient against pest insects
22
Lardier, Pierre-Antoine. "De la Synergie entre insecticide et herbicide cas du carbofuran et de l'atrazine /." Grenoble 2 : ANRT, 1987. http://catalogue.bnf.fr/ark:/12148/cb37607041n.
Full text
23
Bertochi, Helena Romilda. "Distribuição do endosulfan em alguns elementos do ecossistema após aplicação na cultura do algodão." Universidade de São Paulo, 2006. http://www.teses.usp.br/teses/disponiveis/9/9141/tde-06122017-154949/.
Full textAbstract:
Este estudo foi realizado na safra 2002/2003 quando foi avaliado os níveis de endosulfan e seus principais produtos de transformação numa área agrícola localizada na cabeceira de uma microbacia do município de Aguaí-SP. Os objetivos específicos foram: (i) avaliar a movimentação do endosulfan e seus principais transformação no solo sob a cultura do algodão (áreas submetidas à aplicação), (ii) avaliar sua transferência de compartimento (transporte para o solo sob milho e braquiária, adjacentes às áreas aplicadas, e para os corpos aquosos - nascente, lago, córrego jusante e poço), (iii) avaliar os resíduos de endosulfan e seus produtos de transformação nos peixes do açude e (iv) predizer, através de modelagem matemática, a concentração de endosulfan passível de atingir o corpo d\'água e a largura mínima da faixa de contenção (mata ciliar) para impedir a chegada dos produtos no lago. Para tanto, foram realizadas amostragens de solo, sedimento, água dos corpos hídricos e da enxurrada e de peixes, durante sete meses, nas quais foram realizadas análises de α- e β-endosulfan, endosulfan sulfato e endosulfan diol. As análises foram efetuadas por cromatografia gasosa com detecção por espectrometria de massa. Para prever a concentração do produto passível de atingir o açude, tanto associada ao sedimento como na forma livre, foi realizada uma modelagem matemática com base nas propriedades físico-químicas do produto e nas condições edafoclimáticas e de manejo da área estudada. Pôde-se concluir que: (i) o endosulfan e seu produto de transformação endosulfan sulfato não apresentam potencial de lixiviação no solo nas condições estudadas; (ii) a persistência do endosulfan no campo é menor em relação aos estudos de laboratório, sendo que o isômero alfa é o que apresenta a mais rápida degradação e o principal produto de transformação do endosulfan no solo é o endosulfan sulfato; (iii) a principal via de transporte do endosulfan e do endosulfan sulfato no ambiente é o escoamento superficial; (iv) o endosulfan e seus produtos de transformação são transportados associados as micropartículas de solo (\"resíduo-ligado\"); (v) quando a aplicação segue as recomendações estabelecidas pelo fabricante, o produto somente apresenta potencial para atingir áreas adjacentes se houver caminhamento da enxurrada para estas áreas; (vii) o endosulfan e seus produtos de degradação, em sua fase de \"resíduo-ligado\", não apresentam efeito agudo e bioacumulação para as espécies de lambari (Astyanax sp.) e tilápia (Oreochroms sp.) da área nas concentrações observadas neste estudo e (viii) pela modelagem matemática, dentro das condições estudadas, 40 metros de faixa de contenção seria suficiente para impedir a chegada do endosulfan e do endosulfan sulfato nos corpos d\'água, desde que não houvesse fluxo preferencial de enxurrada.The study was carried out during 2002/2003, and its objective was to evaluate the levels of endosulfan and its main transformation products in a fanning area located at the head of a small valley close to the town of Águaí, SP, Brazil. The specific objectives were: (i) to evaluate the dynamics of endosulfan and its main transformation products in the soil beneath a crop of cotton (areas treated with endosulfan), (ii) to evaluate the transfer of endosulfan among various locations [transport from the applied areas into the adjacent areas cultivated with maize (Zea mays) and brachiaria (Brachiaria spp.), and into various bodies of water - a spring, a lake (pond), a small flowing stream and a well], (iii) to evaluate the presence of the residues of endosulfan and its transformation products on fish in the lake and (iv) to predict, using mathematical modeling, the endosulfan concentration able to reach the lake and the minimum width buffer zone (containment strip or riparian vegetation) needed to avoid the arrival of the pesticide in the lake. In order to achieve this, representative samples of the following types were collected - soil, sediment, fish, water from the spring, the pond, the stream and the well, as well as from the runoff. Samples were collected during a period of seven months, and were analyzed for α- and β-endosulfan, endosulfan sulfate and endosulfan diol. The analyses were performed by gas chromatography, with mass spectrometric detection. Mathematical approach was employed to predict the concentration of endosulfan that could reach the lake, and in which form it would be present (free or sorbed to soil microparticles). Input data for the model were the physical-chemical properties of endosulfan, the local soil and climatic conditions, and the management of the study area. It was possible to conclude that: (i) endosulfan and its transformation products endosulfan sulfate do not present potential leaching in the soil profile; (ii) the persistence of endosulfan in the field is shorter than has been found in laboratory studies, α-endosulfan is degrades more rapidly than β-endosulfan and endosulfan sulfate is the main transformation product; (iii) runoff is the principal transport mechanism for endosulfan and endosulfan sulfate in the environment; (iv) the transformation products are transported by attachment to microparticles of soil (\"bound residues\"); (v) when the application of endosulfan follows the recommendations of the manufacturer, the compound is only likely to reach adjacent areas if there is a runoff into these areas; (vii) the products, in the \"bound residue\" form, do not produce acute effects and bioaccumulation in the species of fish lambari (Astyanax sp.) and tilapia (Oreochroms sp.) from the area, and (viii) the modeling has established that, within the conditions of the study, a 40 m wide containment strip is sufficient to prevent the appearance of endosulfan and endosulfan sulfate in bodies of water, considering that there is no prefential flow of runoff water.
24
Koesoemadinata, Santosa. "Aquatic toxicology of selected rice insecticides, with special reference to their effects on fish culture in West Java, Indonesia." Thesis, University of Stirling, 1990. http://hdl.handle.net/1893/3530.
Full textAbstract:
Insecticides are widely used in SE Asian countries to control insect pests in rice, mainly stemborers (Chilo suppresallis) and brown plant hoppers (Nilaparvata lugens). The use of highly toxic insecticide compounds, however, is known to cause serious problem for fish culture in wet rice fields in many of these countries, particularly in Indonesia where this practice assumes a tremendous "house hold economic" importance, as well as being an essential part of the nation's inland aqua-culture production system. The laboratory and field experiments described were carried out to establish whether the application of five selected rice insecticides (fenobucarb, isoprocarb, buprofezin, diazinon and alphamethrin) would influence the growth and production of common carp fingerlings (Cyprinus carpio LINN.) raised in wet rice fields. Laboratory static toxicity tests revealed that the carbamate insecticides (fenobucarb and isoprocarb) were the least toxic insecticide compounds. The 96 hour Median Lethal Concentration (i.e the concentration that killed 50% of the test fish in 96 hours exposure period, under specified conditions) of these insecticides were 5.8mgl-1 and 5.3mgl-1, respectively. The synthetic pyrethroid insecticide alphamethrin was the most toxic insecticide with 96h-LC50 of 0.037mg1-1, while the organophosphate diazinon and the thiadiazin buprofezin showed intermediate toxicity to common carp (96h-LC50 = 2.3mgl-1 and 1.5mgl-1, respectively). A series of five field experiments were consecutively conducted, using 24 specially constructed rice field plots to accomodate the culture of common carp fingerlings for a period of 21 days. A single application of three dose regime, i.e 1/2X, 1 X and 2X of the recommended dose rate for insect control was given as treatment in each experiment. The survival of fish in all experiments were not significantly influenced by the insecticide treatment (P > 0.05). The growth rate and the production of fish biomass in rice fields treated with isoprocarb, buprofezin, diazinon and alphamethrin, were also found to be comparable with those in the untreated control plot (P > 0.05). In the rice fields treated with the highest dose rate of fenobucarb (1500gha-1 ,Al), the growth and production of fish were significantly lower than those in the untreated control rice fields (P < 0.05). Observations on the rice field biota revealed no definite pattern in the temporal changes of the population of zooplankton and macroinvertebrates both in the insecticide treated plots as well as in the untreated control plots. The minimum effects of the insecticide treatment to fish and rice field biota observed in the experiment were presumably due to several factors, mainly because a significant amount of the compounds were adsorbs by the rice field soil and aquatic vegetations and not onto the water, causing less toxicity, followed by the rapid flushing of the chemicals from the rice field system. The composition of the diet of common carp fingerlings in the rice field was found to be similar with those reported in the natural ponds, consisting mainly of aquatic insects (and their larvae), crustaceans, benthic macroinvertebrates and plant detritus. Based on the results of the present experiments, of the five insecticide compounds tested, diazinon and fenobucarb appeared to produce greater risk to fish when used in rice-fish farming. The use of agrochemicals in rice-fish farming should be carefully managed and controlled, using selected low toxic and non-persistent insecticides based on the result of laboratory and field toxicity tests.
25
Bucur, Bogdan. "Capteurs et biocapteurs pour l'analyse par injection en flux." Bucarest, 2005. http://www.theses.fr/2005PERP0648.
Full textAbstract:
Ce travail a pour objet la mise au point de (bio)capteurs utilisables dans des systèmes d'analyse en flux. L'AChE a été choisie comme bio récepteur biologique pour la mise au point des méthodes sensibles pour la détection des insecticides neurotoxiques. Deux axes principaux de recherche ont été suivis : (i) la mise au point des nouvelles méthodes d'immobilisation de l'AChE basées sur des liaisons de bioaffinité (ii) l'utilisation des enzymes provenant de différentes origines ou modifiées génétiquement pour améliorer la sensibilité et la sélectivité des analyses. Les biocapteurs développés dans cette thèse ont été mis au point et optimisés dans des systèmes appelés " batch " ou utilisés couplés avec les techniques d'analyse en flux. L'immobilisation par affinité de l'AChE d'une manière originale a été réalisée en utilisant la Con A (une lectine) qui peut se lier avec les sucres se trouvant à la surface de l'enzyme. Les deux méthodes proposées permettent l'immobilisation orientée de l'AChE, l'élimination des barrières de diffusion, la réutilisation des transducteurs. . . L'utilisation des enzymes provenant des organismes différents permet la construction de biocapteurs avec des performances améliorées. Ce travail a permis la mise au point de biocapteurs très sensibles pour la détection des insecticides carbamates grâce à l'utilisation de trois mutants de Dm. En plus, il a été proposé un système d'analyse en flux capable de faire la différence entre les inhibitions produites par des insecticides et d'autres composés. Au vu les résultats obtenus, nous pouvons envisager des applications potentielles études dans le domaine du monitorage de l'environnementThis work was focused on the development of (bio)sensors for the flow injection analysis. The AChE was chosen as biocomponent for the realisation ofbiodevices, which are sensitive towards neurotoxic insecticides. Two main research directions were followed in this study: (i) the realisation of new methods for AChE immobilisation based on bioaffinity links (ii) the use of enzymes that are obtained from different sources or genetically modified toimprove the sensitivity and the selectivity of the determinations. The biosensors developed in this thesis were studied and optimised in " batch " systems or used coupled with flow analysis techniques. The bioaffinity AChE immobilisation in an original manner was carried out with Con A (a lectine) that interacts with the sugars present on the surface of the enzyme. The immobilisation is performed in several independent steps and produce a sandwich like structure in which the Con A makes a bridge between the AChE and the support activated by a sugar. The two proposed methods allowsthe oriented immobilisation of the AChE, the elimination of the diffusion barriers, the reuse of the transducers. . . The use of the enzymes from different organisms allows the construction of biosensors with improved performances. In this thesis, we constructed biosensors highly sensitive towards the carbamate insecticides by using three mutants of Dm. Also, it was proposed a flow analysis system able to differentiate between the inhibitions produced by the insecticides or by interfering compounds Considering the obtained results, the biosensors could be successfully used for environmental monitoring
26
Bendahou, Najib, and Michel Bounias. "Toxicologie comparée de deux classes d'insecticides : un organophosphore le fénitrothion et un pyréthrinoïde "la cyperméthrine" chez l'abeille mellifère (Apis mellifera mellifera. L.) : études au laboratoire et sur le terrain." Metz, 1994. http://docnum.univ-lorraine.fr/public/UPV-M/Theses/1994/Bendahou.Najib.SMZ9449.pdf.
Full textAbstract:
L'étude comparative de la toxicité de deux insecticides, la cyperméthrine et le fénitrothion sur l'abeille mellifère (Apis mellifera mellifera. L) est développée en trois parties appuyées sur une synthèse bibliographique générale. La première au laboratoire vise à évaluer la toxicité létale de ces deux insecticides, à l'aide d'un nouveau concept algèbrique, dérivé de l'équation de Hill comme alternative à la DL50. Les paramètres tl(50) le coefficient de Hill (nt) et la vitesse maximale de mortalité, permettent une évaluation précise de la toxicité des substances étrangères, et permettent de classer les composés relativement à leur paramètres calculés, dans notre cas la cyperméthrine semble être plus toxique que la fénitrothion. La seconde partie présente l'analyse de l'impact de la cyperméthrine et du fénitrothion sur le métabolisme glucidique (glucose & tréhalose) et enzymatique atpase (Na+, K+) & acétylcholinésterase (AChE). La glycémie, et la tréhalosémie, se trouvent affectées par la cyperméthrine et le fénitrothion. Atpase (Na+, K+) & acétylcholinéstérase (AChE) sont inhibées toutes les deux par la cyperméthrine et le fénitrothion, cependant l'effet de la cyperméthrine l'acétycholinésterase n'est pas aussi significative que celle induite par le fénithrothion. Le dernier chapitre porte sur l'étude en plein champs des perturbations, du métabolisme glucidique et enzymatique, de la surface alvéolaire, de l'activité des abeilles, dans le comportement et enfin dans la disparition de la majeure partie des ruches traitées avec une dose sublétale de cyperméthrineThe aim of this thesis is to study comparatively the toxicity of two insecticides, cypermethrin and fenitrothion on honeybees (Apis mellifera mellifera. L). Following a general bibliography synthesis, the first chapter presents a comparative evaluation of the two insecticides, including the use of a new algebraic concepts from the Hill equation as an alternative to LD50. This new toxicological parameters allows a strong evaluation of the toxicity of any substance, and can be used to compare and to classify many compounds with rspect to their relative toxicity, while completely avoiding the problem of arbitrary choices in the calculation of LD50. In concordance to theses news parameters, cypermethrin seems to be more toxic than fenitrothion. The second chapter shows the impact of cypermethrin and fenitrothion on the haemolymph carbohydrates (glucose and trehalose) where these two insecticides induced a serious damage. Both (Na+, K+)ATPase and Acétylcholinesterase were also affected by these two insecticides, however cypermethrin did not induce any significant inhibition of acetylcholinesterase comparatively to the fenitrothion's action. The last chapter deals with field studies showing many perturbations occuring in treated hives in contrast to control ones on : foraging activity, hive'smortality, bees behaviour, brood areas, glucosemia and threhalosemia and ATPase of the colonies fed continuousely by cypermethrin at subletal doses
27
Rajendran, Candasamy. "Toxicology of selected plant products and insecticides in the red flour beetle, Tribolium castaneum (herbst) and the fruit fly, Drosophila malanogaster (meig.)." Thesis, University of Newcastle Upon Tyne, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.239658.
Full text
28
Meled, Maggy. "Synergie de la deltaméthrine et du prochloraze chez l'abeille Apis mellifera L : une approche métabolique." Aix-Marseille 3, 1996. http://www.theses.fr/1996AIX30121.
Full textAbstract:
Les importantes mortalites d'abeilles liees a l'emploi en association de fongicides et d'insecticides classes comme non dangereux pour les abeilles sont a l'origine des etudes sur la toxicite de l'association de la deltamethrine et du prochloraze chez l'abeille. L'utilisation de ces produits en doses subletales a permis de mettre en evidence une synergie de mortalite chez les abeilles d'ete, suite a un traitement en association des deux pesticides. Une difference de sensibilite, envers l'association de ces deux pesticides, a ete mise en evidence entre les abeilles d'ete et les abeilles d'hiver. Chez ces dernieres, la dose de deltamethrine doit etre augmentee d'un facteur 8 pour obtenir une synergie. Une interference d'action sur des cibles communes aux deux pesticides ou bien une deviation metabolique de la metabolisation de la deltamethrine par l'action du prochloraze sur les enzymes de detoxication peuvent etre envisagees pour expliquer le mecanisme de synergie. C'est cette seconde hypothese que nous avons testee. Cela a necessite la mise au point de l'extraction des monooxygenases a cytochrome p450 microsomales puisqu'elles n'avaient jamais ete obtenues sous leurs formes actives chez cet insecte. Une difference quantitative de l'activite des monooxygenases a cytochrome p450 et des glutahion-s-transferases a pu etre constatee entre les abeilles d'ete et d'hiver. Le suivi de ces enzymes dans l'intestin a ensuite ete realise apres traitement des abeilles d'ete et d'hiver. Nous avons observe une augmentation de la teneur et des activites des monooxygenases immediatement apres traitement en association ainsi qu'une diminution de l'activite des gst chez les abeilles d'ete. Ces constatations ne sont pas visibles avec les abeilles d'hiver alors que les conditions pour avoir un effet synergique sont remplies. Le prochloraze inhibe, in vitro, diverses activites monooxygenasiques et la metabolisation ex vivo de la testosterone. Son action est cependant plus specifique et moins efficace que chez les vertebres. Bien que le prochloraze inhibe aussi, ex vivo, le metabolisme de la deltamethrine apres un traitement au prochloraze seul ou en association, le profil metabolique de la deltamethrine, in vivo, n'est pas modifie. L'hypothese de la deviation metabolique semble donc peu probable pour, a elle seule, expliquer la synergie de mortalite chez les abeilles due a l'association deltamethrine-prochloraze
29
Heath, Susan M. "Interactions among Temperature, pH, and Cyfluthrin on Survival of the Fathead Minnow Pimephales promelas." Thesis, University of North Texas, 1991. https://digital.library.unt.edu/ark:/67531/metadc500866/.
Full textAbstract:
The 96-hr LC50 of cyfluthrin in Pimephales promelas ata temperature of 23*C and a pH of 8 was 1.08 g/L. The toxicity of cyfluthrin was inversely related to temperature and pH. A temperature of 10*C and a pH of 6 significantly decreased the 96-hr LC50 to 0.009 gg/L. Likewise, sublethal exposures to cyfluthrin significantly affected the fathead minnow's ability to tolerate high and low temperatures. Cyfluthrin compromised the fathead minnow's lower temperature tolerance (CTMin) by 60C and the upper temperature tolerance (CTMax) by 20C. Although cyfluthrin may not be present in the environment in large amounts due to its physical and chemical properties, small concentrations ( g/L) may adversely affect fish populations.
30
Soubirou, Jean-Luc. "De l'intoxication aux organo-phosphores : aspects civil et militaire." Bordeaux 2, 1991. http://www.theses.fr/1991BOR2M145.
Full text
31
Winkaler, Elissandra Ulbricht [UNESP]. "Aspectos ecotoxicológicos dos inseticidas diflubenzuron e teflubenzuron para o pacú (Piaractus mesopotamicus)." Universidade Estadual Paulista (UNESP), 2008. http://hdl.handle.net/11449/100221.
Full textAbstract:
Made available in DSpace on 2014-06-11T19:30:30Z (GMT). No. of bitstreams: 0
Previous issue date: 2008-07-18Bitstream added on 2014-06-13T19:00:42Z : No. of bitstreams: 1
winkaler_eu_dr_jabo.pdf: 2401389 bytes, checksum: 3b8d20a39c2ee3641205a9c6930923aa (MD5)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Dentre os agrotóxicos comumente utilizados na piscicultura para controle de ectoparasitos e insetos aquáticos, destacam-se o diflubenzuron (Dimilin®) e o teflubenzuron (Nomolt®), inseticidas com ação reguladora do crescimento. Na aqüicultura, o tratamento com inseticidas pode ser realizado com a aplicação direta na água, ou administração na ração dos animais. Apesar de muito utilizados, poucos são os trabalhos sobre ecotoxicologia, comportamento e bioacumulação do diflubenzuron (DFB) e teflubenzuron (TFB) na água e seus efeitos em organismos aquáticos de clima tropical. Os objetivos deste trabalho foram: estimar a toxicidade (CL(50-96h)) do DFB e TFB para o pacu (Piaractus mesopotamicus), calcular o risco alimentar para o consumo humano, determinar resíduos de DFB e TFB na água, sedimento e músculo de pacus, após a exposição aos inseticidas na água ou na ração dos peixes e analisar a atividade hepática das enzimas glutationa-S-transefrase (GST) e catalase (CAT) em pacus alimentados com ração acrescida de DFB ou TFB. A CL50;96h do DFB para o pacu foi superior a 1200 mg.L-1 e a do TFB, superior a 1000 mg.L-1. Os resíduos de DFB foram detectáveis até 7 dias após a aplicação (com 18,3% de resíduo) e para o TFB, foram detectáveis ate o terceiro dia (8% de resíduo). No sedimento, as maiores concentrações de DFB e TFB foram observadas nas primeiras 24 h e em todos os períodos amostrados foram detectados resíduos dos inseticidas. Nos filés dos pacus foram detectados resíduos dos inseticidas após a alimentação com a ração tratada e após aplicação de DFB e TFB na água. A ingestão diária estimada (IDE) de DFB e TFB encontra-se acima dos valores de ingestão diária aceitável (IDA), mesmo para as amostras com menores valores de resíduos detectados nos filés do pacu. Em relação aos biomarcadores bioquímicos...
Diflubenzuron and teflubenzuron are growth regulator inhibitors insecticides, used to control ectoparasites in fish and aquatic insects. In aquaculture these pesticides can be injected directly in the water or in the fish food. Besides their large utilization, there are few works about the effects of these insecticides on the fish metabolism and biomagfication, especially in tropical aquatic organisms. This study aims to: evaluate the acute toxicities (LC(50-96h)) in pacu (Piaractus mesopotamicus), measure the risk food for human consumption, determinate residues of DFB and TFB in water, sediment and muscle of pacus after the management of the insect-powders on water or in the fish food and to analyze the hepatical activity of the enzymes catalase (CAT) and glutathione-S-transferase (GST) in fishes fed with ration plus DFB or TFB. The LC((50- 96h)) of DFB and TFB for the pacu was higher than 1.200 mg.L-1 and 1.000 mg.L-1, respectively. The residues TFB were detected until the thirth day (8% of residue) and DFB until seventh day after application in the water (18,3% of residue). In the sediment, the highest concentrations of DFB and TFB had been observed in the first 24 h and in all the samplings there were . In muscle of pacus, residues of the insecticides had been detected after the feeding with the ration treated and after application to DFB and TFB in the water. The daily ingestion estimate (DIE) of DFB and TFB meets above of the values of acceptable daily ingestion (DAI), exactly for the samples with lesser values of residues detected in filés of pacu. For the enzymes the CAT activity was not affected by both pesticides, but the GST activity was reduced five days after the feeding. Besides the importance of the evaluation of the toxicity of DFB and TFB for the fish, the determination of residues and the alimentary risk, it can subsidize the determination of measures of sanitary... (Complete abstract click electronic access below)
32
Gosselin-Badaroudine, Pascal. "Caractérisation des canaux AmNav1, AmNav2 et VdNav1 : nouvelles méthodes pour évaluer la toxicité d'insecticides." Doctoral thesis, Université Laval, 2016. http://hdl.handle.net/20.500.11794/28241.
Full textAbstract:
Tableau d'honneur de la Faculté des études supérieures et postdoctorales, 2016-2017.Les canaux sodiques dépendants du voltage (NaV) participent à la genèse et la transmission de l'influx nerveux via l'initiation du potentiel d'action. Chez l'insecte, ces protéines sont la cible de nombreux insecticides neurotoxiques. Étant donné le déclin des populations d'insectes pollinisateurs observé récemment, il devient désormais important d'avoir des méthodes permettant le développement d'insecticides qui ne ciblent pas les pollinisateurs. L'objectif général de ma thèse a donc été de mettre au point des méthodes in-vitro et insilico pouvant être appliquées à grande échelle dans le but d'évaluer le risque potentiel que certains insecticides pourraient représenter pour l'abeille. Pour ce faire, nous avons procédé à la caractérisation biophysique et pharmacologique des canaux sodiques NaV1 et NaV2 d'abeille. Nous avons aussi créé un modèle moléculaire du canal NaV1 d'abeille permettant la conception rationnelle d'insecticides. De plus, nous avons caractérisé le canal NaV1 de Varroa destructor, un parasite important de l'abeille. Les études insérées dans cette thèse ont permis de démontrer que le canal NaV2 n'est pas une cible secondaire des insecticides pyréthroïdes. De plus, nous avons pu mesurer les effets et l'affinité d'insecticides sur leur cible moléculaire chez l'abeille suite à l'expression du canal NaV1 d'abeille en ovocyte de grenouille. Cela permet le criblage de composé à haut débit afin de sélectionner des composés représentant un faible risque pour l'abeille. De même, l'expression du canal NaV1 de Varroa destructor en système d'expression hétérologue permettrait l'utilisation de la méthode de criblage de composés à haut débit dans le but d'identifier des insecticides qui représentent un risque important pour cette peste. D'ailleurs, nous avons déterminé que le fluvalinate, un insecticide pyréthroïde utilisé pour contrôler les populations de Varroa destructor dans les ruches d'abeille, a une affinité différente pour le canal NaV1 d'abeille que pour celui de Varroa destructor. Cela indique une différence dans les sites de liaisons du composé qui pourrait éventuellement être exploitée. Mes travaux ouvrent donc la voie au développement de composés ciblant davantage des animaux nuisibles comme le Varroa destructor que des animaux utiles comme l'abeille. De plus, les caractérisations effectuées pourraient être utiles pour des études centrées sur les rôles et l'évolution des canaux ioniques appartenant aux familles NaV et CaV.
Voltage-gated sodium channels (NaV) are implicated in the genesis and transmission of action potentials. In insects, these proteins are the target of a number of neurotoxic insecticides. In the background of the pollinator decline observed recently, it has become necessary to develop insecticides which do not target beneficial insects such as bees. The main objective of my thesis was to develop in-vitro and in-silico methods which could be used on a large scale to evaluate the risk associated with the use of certain compounds for bees. To do so, we assessed the biophysical and pharmacological properties of the honeybee's NaV1 and NaV2 channels. We also created a molecular model for the NaV1 channel which enables the rational design of insecticides. Furthermore, we have characterized the Varroa destructor NaV1 channels. The investigations featured in this thesis demonstrate that the NaV2 channel is not a secondary target of pyrethroïd insecticides. However, following expression in frog oocytes, it is possible to quantify the effects and affinity of those insecticides for their molecular target in the honeybee, the NaV1 channel. This makes possible the use of high throughput screening technologies for the selection of insecticides which would represent a small risk for bees. Moreover, the expression of Varroa destructor NaV1 channels in frog oocytes enables the use of medium throughput screening technologies to identify compounds which could be deleterious for this pest. Indeed, we determined that fluvalinate, a pyrethroïd insecticide used to control Varroa population in honeybee hives, has an affinity for the honeybee NaV1 channel that is different than that for the Varroa channel. This indicates that the binding site of this compound on the Varroa channel would differ from the binding site on the bee channel. This difference could be exploited to improve the specificity of fluvalinate. The work presented here represents a first step in the development of methods which could be used to decrease the toxicity of insecticides for bees while increasing their specificity of against pests such as Varroa destructor. Furthermore, the characterizations performed provide new insights on topics such as the roles and the evolution of NaV et CaV channels.
33
Istamboulié, Georges. "Biocapteur associant l’acétylcholinestérase et la phosphotriesterase pour un contrôle environnemental des insecticides organophosphorés." Perpignan, 2009. http://www.theses.fr/2009PERP1002.
Full textAbstract:
Ce travail de thèse présente la mise au point de biocapteurs enzymatiques pour une détection sensible et sélective de deux insecticides organophosphorés (OPs) considérés par la Communauté Européenne comme des polluants prioritaires pour les eaux de surface : le chlorpyriphos (CPO) et le chlorfenvinphos (CFV) (directive EC 2455/2001/E). La très haute sensibilité des capteurs a été obtenue en combinant l’utilisation d’une acétylcholinestérase (AChE) modifiée génétiquement (MG) avec une méthode d’immobilisation orientée par affinité His-Ni sur des billes magnétiques. La sélectivité du système a été obtenue en utilisant la phosphotriestérase (PTE), une enzyme isolée à partir de Pseudomonas diminuta, qui est capable d’hydrolyser certains OPs. Un capteur bienzymatique associant l’AChE à la PTE a permis une détection sélective du CPO et du CFV en solutions simples. L’analyse de mélanges des deux OPs a été rendue possible par l’utilisation d’un réseau neuronal intégrant trois capteurs dont deux mono-enzymatiques (AChE sauvage ou MG) et un bi-enzymatique (AChE-MG + PTE). Ce système a permis une détection spécifique des deux OPs pour une large zone de concentrations. Une étude complémentaire a montré que l’immobilisation de la PTE sur une colonne intégrée dans un système en flux peut constituer un outil efficace pour la détoxification d’eaux de surface contaminées par les deux OPs étudiés. Enfin, la dernière partie de la thèse a été consacrée à l’étude d’un nouveau médiateur permettant l’oxydation de la thiocholine à 100 mV vs Ag/AgCl : le PEDOT:PSSThis work presents the development of enzymatic sensors for the sensitive and selective determination of two organophosphate (OPs) insecticides pointed out by European Community as priority pollutants of surface waters: chlorpyriphos (CPO) and chlorfenvinphos (CFV) (directive EC 2455/2001/E). The very high sensitivity of the sensors has been achieved by combining the use of a genetically-modified (GM) acetylcholinesterase (AChE) with an oriented immobilisation method based on His-Ni affinity on magnetic beads. The selectivity of the system has been obtained by using phosphotriestérase (PTE), an enzyme isolated from Pseudomonas diminuta, which has the capability of hydrolysing certain OPs. A bi-enzymatic sensor associating AChE and PTE has allowed the selective detection of CPO and CFV in simple solutions. The analysis of OPs mixtures has been then performed by using an artificial neural network incorporating three sensors, two mono-enzymatic (wild AChE or GM-AChE) and one bi-enzymatic (GM-AChE + PTE). This system has allowed the specific detection of the two OPs in a wide range of concentrations. A complementary study has shown that immobilizing PTE into a column integrated in a flow system allows the detoxification of surface waters contaminated by the two studied OPs. Finally, the last part of this work has been devoted to the study of a new potential mediator for thiocholine oxidation : PEDOT-PSS
34
Iannacone, Oliver José. "Efecto insecticida de cuatro extractos botánicos y del cartap sobre la polilla de la papa Phthorimaea operculella (Zeller) (Lepidoptera: Gelechiidae) y en cuatro controladores biológicos, en el Perú." Doctoral thesis, Universidad Nacional Mayor de San Marcos, 2003. https://hdl.handle.net/20.500.12672/3317.
Full textAbstract:
Phthorimasa(Zeller)(Lepidoptera: Gelechiidae) es una laga clave en el cultivo de papa en el Perú , El depredadorChrysoperla externa hagen y las tres microavispasparasitoides Trichogrammma pintoi Vosgelé, Copidosoma koehleri blanchard y Dolichogenidia gelechiidivoris(Marsh) son controladores biológicos promisorios de plagas agrícolas clave en el Perú, pais donde no se ha investigado los efectos de la integración de métodos biológicos y productos biocidas al manejo integrado de plagas.Phthorimaea operculella (Zeller) (Lepidoptera: Gelechiidae) is a key pest in potato crops in Peru. Chrysoperla externa Hagen and the three parasitoid microwasps Trichogramma pintoi Voegelé, Copidosoma Koehleri Blanchard and Dolichogenidia gelechiidivoris (Marsh) are promissory biological control agents of key agricultural pests in peru, where the effects of integration of biological control agents and chemical or natural products into integrated pest management have not been investigated.
Tesis
35
Saffih-Hdadi, Kawtar. "Analyse couplée du devenir du parathion et du paraoxon dans le sol et leur impact écotoxicologique sur les Nématodes." Avignon, 2003. http://www.theses.fr/2003AVIG0608.
Full text
36
Allen, H. Joel. "A Behavioral Model for Detection of Acute Stress in Bivalves." Thesis, University of North Texas, 1998. https://digital.library.unt.edu/ark:/67531/metadc277998/.
Full textAbstract:
A behavioral model for acute responses in bivalves, was developed using time series analysis for use in a real-time biomonitoring unit. Stressed bivalves closed their shell and waited for the stressful conditions to pass. Baseline data showed that group behavior of fifteen bivalves was periodic, however, individuals behaved independently. Group behavior did not change over a period of 20 minutes more than 30 percent, however, following toxic exposures the group behavior changed by more than 30 percent within 20 minutes. Behavior was mathematically modeled using autoregression to compare current and past behavior. A logical alarm applied to the behavior model determined when organisms were stressed. The ability to disseminate data collected in real time via the Internet was demonstrated.
37
Vergottini, Toro Gianella Mariolin. "Toxicidad de algunos insecticidas de origen vegetal sobre Xanthogaleruca luteola Müller (Coleoptera: Chrysomelidae)." Tesis, Universidad de Chile, 2011. http://www.repositorio.uchile.cl/handle/2250/112804.
Full textAbstract:
Memoria para optar al Título Profesional de Ingeniero Agrónomo Mención Sanidad VegetalDurante la temporada 2008-2009, se evaluó en laboratorio la toxicidad de cuatro insecticidas de origen botánico; Biomilbe, Biobug, Bugitol y Garlic Barrier, sobre larvas y adultos de la vaquita del olmo, Xanthogaleruca luteola Müller (Coleoptera: Chrysomelidae), colectados desde árboles ubicados en el Parque O`Higgins, Región Metropolitana. Los insecticidas se aplicaron en cuatro dosis distintas cada uno, mediante una torre de Potter, y su acción se evaluó de tres formas, directa, para determinar la toxicidad por contacto, sobre hojas, para medir el efecto residual, y una prueba con una bandeja que contenía por un lado hojas asperjadas con la mezcla insecticida y por el otro hojas sólo asperjadas con agua, para observar cualquier efecto de repelencia. Para los ensayos se utilizó un diseño estadístico completamente aleatorio, con los cuatro insecticidas en el primer y segundo ensayos, más un testigo sin insecticida, y cuatro repeticiones por tratamiento. La unidad experimental consistió en una placa Petri con 20 individuos. La mortalidad se evaluó 24 y 48 horas después de la aspersión sobre hojas, y a los 30 y 60 minutos en el experimento por aplicación directa. Los porcentajes de mortalidad se sometieron a pruebas no paramétricas sin normalización de datos y pruebas de separación de promedios. Para el ensayo en bandejas se comparó el porcentaje de larvas ubicadas en cada sector, tratado y no tratado. Los porcentajes de mortalidad obtenidos fueron muy bajos. El mayor promedio de mortalidad se obtuvo con Bugitol al 4%, con 46,3% y 37,5% de mortalidad en larvas y adultos respectivamente. En la prueba preliminar de repelencia se encontraron efectos marcados en las hojas tratadas con Biomilbe y Biobug, con las larvas concentrándose en mayor porcentaje sobre las hojas asperjadas sólo con agua.
The toxicity of four botanical insecticides, Biomilbe, Biobug, Bugitol, and Garlic Barrier, was evaluated in the laboratory onto larvae and adults of the elm leaf beetle Xanthogaleruca luteola Müller (Coleoptera: Chrysomelidae), which were collected in Parque O`Higgins, Santiago, Metropolitan Region of Chile. The insecticides were applied at four concentrations with a Potter spray tower, and their action was evaluated in three ways, directly, to determine contact toxicity, onto leaves, to measure contact effect of residues, and a test using a tray with leaves sprayed with the insecticide on one side, and leaves sprayed only with water in the other, to observe any effect of repellence. For the first two experiments, a completely random statistical design was used, with four insecticide treatments at four concentrations each, and an untreated control, and four replicates per treatment. The experimental unit was a Petri dish with 20 individuals. Mortality was evaluated at 24 and 48 hours after spraying onto leaves, and after 30 and 60 minutes in the experiment of immersion of leaves. Percentages of mortality were subjected to non-parametric tests without standardization of data and range tests to separate means. The percentages of mortality obtained were very low. The greatest mortality was obtained with Bugitol at 4%, with 46,3% y 37,5% of mortality of larvae and adults respectively. The preliminary repellency test show marked effects on the leaves treated with Biomilbe y Biobug, and higher percentage of larvae concentrated on spray leaves only with water.
38
Winkaler, Elissandra Ulbricht. "Aspectos ecotoxicológicos dos inseticidas diflubenzuron e teflubenzuron para o pacú (Piaractus mesopotamicus) /." Jaboticabal : [s.n.], 2008. http://hdl.handle.net/11449/100221.
Full textAbstract:
Orientador: Joaquim Gonçalves Machado NetoBanca: Elisabeth Criscuolo Urbinati
Banca: Claudinei da Cruz
Banca: Flávio Ruas de Moraes
Banca: Gilson Pereira de Olivera
Resumo: Dentre os agrotóxicos comumente utilizados na piscicultura para controle de ectoparasitos e insetos aquáticos, destacam-se o diflubenzuron (Dimilin®) e o teflubenzuron (Nomolt®), inseticidas com ação reguladora do crescimento. Na aqüicultura, o tratamento com inseticidas pode ser realizado com a aplicação direta na água, ou administração na ração dos animais. Apesar de muito utilizados, poucos são os trabalhos sobre ecotoxicologia, comportamento e bioacumulação do diflubenzuron (DFB) e teflubenzuron (TFB) na água e seus efeitos em organismos aquáticos de clima tropical. Os objetivos deste trabalho foram: estimar a toxicidade (CL(50-96h)) do DFB e TFB para o pacu (Piaractus mesopotamicus), calcular o risco alimentar para o consumo humano, determinar resíduos de DFB e TFB na água, sedimento e músculo de pacus, após a exposição aos inseticidas na água ou na ração dos peixes e analisar a atividade hepática das enzimas glutationa-S-transefrase (GST) e catalase (CAT) em pacus alimentados com ração acrescida de DFB ou TFB. A CL50;96h do DFB para o pacu foi superior a 1200 mg.L-1 e a do TFB, superior a 1000 mg.L-1. Os resíduos de DFB foram detectáveis até 7 dias após a aplicação (com 18,3% de resíduo) e para o TFB, foram detectáveis ate o terceiro dia (8% de resíduo). No sedimento, as maiores concentrações de DFB e TFB foram observadas nas primeiras 24 h e em todos os períodos amostrados foram detectados resíduos dos inseticidas. Nos filés dos pacus foram detectados resíduos dos inseticidas após a alimentação com a ração tratada e após aplicação de DFB e TFB na água. A ingestão diária estimada (IDE) de DFB e TFB encontra-se acima dos valores de ingestão diária aceitável (IDA), mesmo para as amostras com menores valores de resíduos detectados nos filés do pacu. Em relação aos biomarcadores bioquímicos... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: Diflubenzuron and teflubenzuron are growth regulator inhibitors insecticides, used to control ectoparasites in fish and aquatic insects. In aquaculture these pesticides can be injected directly in the water or in the fish food. Besides their large utilization, there are few works about the effects of these insecticides on the fish metabolism and biomagfication, especially in tropical aquatic organisms. This study aims to: evaluate the acute toxicities (LC(50-96h)) in pacu (Piaractus mesopotamicus), measure the risk food for human consumption, determinate residues of DFB and TFB in water, sediment and muscle of pacus after the management of the insect-powders on water or in the fish food and to analyze the hepatical activity of the enzymes catalase (CAT) and glutathione-S-transferase (GST) in fishes fed with ration plus DFB or TFB. The LC((50- 96h)) of DFB and TFB for the pacu was higher than 1.200 mg.L-1 and 1.000 mg.L-1, respectively. The residues TFB were detected until the thirth day (8% of residue) and DFB until seventh day after application in the water (18,3% of residue). In the sediment, the highest concentrations of DFB and TFB had been observed in the first 24 h and in all the samplings there were . In muscle of pacus, residues of the insecticides had been detected after the feeding with the ration treated and after application to DFB and TFB in the water. The daily ingestion estimate (DIE) of DFB and TFB meets above of the values of acceptable daily ingestion (DAI), exactly for the samples with lesser values of residues detected in filés of pacu. For the enzymes the CAT activity was not affected by both pesticides, but the GST activity was reduced five days after the feeding. Besides the importance of the evaluation of the toxicity of DFB and TFB for the fish, the determination of residues and the alimentary risk, it can subsidize the determination of measures of sanitary... (Complete abstract click electronic access below)
Doutor
39
Tapia, Vilchez Fernando Jesús. "Interacción de temperatura y Clorpirifos (PYRINEX ®) sobre la estabilidad genética de Poecilia reticulata “GUPI”." Bachelor's thesis, Universidad Nacional Mayor de San Marcos, 2017. https://hdl.handle.net/20.500.12672/7159.
Full textAbstract:
Clorpirifos (Pyrinex ®) es un insecticida organofosforado de amplio uso en la agricultura, la extensión de su uso en el Perú no está documentada, sin embargo, se estima que podría ser parte de una variedad de tóxicos presentes en el agua y que tendrían efectos deletéreos sobre poblaciones locales de peces. Interacciones de la temperatura (17, 25 y 30 °C) fueron evaluadas, en presencia de concentraciones sub-letales de Clorpirifos (0, 0.005, 0.010, 0.015, 0.020 y 0.025 mg/L) enfocadas en estabilidad genética expresada en términos de frecuencia de micronúcleos y otras anormalidades nucleares sobre Poecilia reticulata “gupi”. Los resultados muestran que las interacciones fueron significativas (p = 0.001), la frecuencia de anormalidades nucleares no difiere entre grupos control independientemente de la temperatura, se observaron incrementos significativos con la concentración (p = 0.001) y la temperatura (p = 0.001), al mismo tiempo se reportó una CL50 para Clorpirifos a 17°C de 0.015 mg/L, no se reportó mortalidad a 25 y 30°C. Se sugiere que la toxicidad varía en sus mecanismos de acción según las interacciones: (1) a temperaturas altas (25 y 30°C) la genotoxicidad se incrementa, sin mortalidad; y (2) a temperaturas bajas (17°C), se reducen los procesos de formación de anormalidades nucleares, sin embargo, la mortalidad se ve aumentada significativamente debido a que Clorpirifos reduce umbral de tolerancia de temperatura de P. reticulata. Se confirma el alto riesgo de Clorpirifos y sus interacciones con la temperatura, por lo que se sugiere que los ensayos de ecotoxicidad deben tomar en consideración la temperatura del ambiente y no sólo la temperatura óptima de la especie en evaluación lo cual conllevaría a una sub- o sobre estimación de la toxicidad. Estas interacciones de contaminantes y medio ambiente (en especial la temperatura) deben ser considerados en el contexto de eventos climáticos extremos, cambio climático y de cambios en la actividad agrícola e industrial.Tesis
40
Abe, Flavia Renata. "Avaliação ecotoxicológica e risco ambiental dos inseticidas utilizados no controle da larva de Aedes aegypti para Daphnia magna, Lemna minor e peixes /." Jaboticabal :, 2012. http://hdl.handle.net/11449/86654.
Full textAbstract:
Orientador: Joaquim Gonçalves Machado NetoBanca: Robinson Antonio Pitelli
Banca: Marco Antonio de Andrade Belo
Resumo: O uso dos larvicidas temefós e diflubenzuron (DFB) na agricultura, aquicultura e combate a vetores de doenças pode acarretar desequilíbrios ambientais, e a ocorrência destes efeitos são analisados por estudos ecotoxicológicos e avaliações de risco ambiental. Objetivou-se: i) classificar os larvicidas DFB e temefós pela toxicidade aguda e crônica para os peixes tilápia-do-Nilo (Oreochromis niloticus) e mato grosso (Hyphessobrycon eques), para a macrófita Lemna minor e para microcrustáceo Daphnia magna; ii) avaliar o efeito do sedimento na biodisponibilidade dos larvicidas; iii) classificar os larvicidas quanto ao risco ambiental em ecossistema aquático; iv) avaliar a concentração de resíduos dos larvicidas nas águas dos testes agudos e crônicos de tilápia-do-Nilo, na presença e ausência de sedimento; v) avaliar o potencial de lixiviação e de escoamento superficial de ambos os larvicidas e vi) verificar os efeitos tóxicos dos larvicidas no fígado e brânquia de tilápias-do-Nilo expostas aos testes de toxicidade aguda. O DFB classifica-se como praticamente não-tóxico para L. minor, ligeiramente tóxico para H. eques e O. niloticus, e extremamente tóxico para D. magna. O temefós é ligeiramente tóxico para L. minor, moderadamente tóxico para H. eques e O. niloticus e extremamente tóxico para D. magna. A exposição dos peixes à baixas concentrações de DFB por longos períodos causa redução no crescimento dos peixes, e o temefós causa mortalidade. O temefós causa redução na taxa de crescimento relativa de L. minor expostas à doses sub-letais. Ambos os larvicidas causam mortalidade para D. magna em testes crônicos. A presença de sedimento reduz a biodisponibilidade dos larvicidas nas águas de testes com L. minor. O DFB classifica-se como de baixo risco ... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: The use of the pesticide temephos and diflubenzuron (DFB) in agriculture, aquaculture and in the disease vectors control may cause environmental disequilibrium, and these effects are analysed for ecotoxicological studies and environmental risk assessments. This study aimed to: i) classify the pesticides DFB and temephos by the acute and chronic toxicity to the fishes tilapia (Oreochromis niloticus) and mato grosso (Hyphessobrycon eques), the macrophyte Lemna minor and the microcrustaceans Daphnia magna; ii) evaluate the effect of sediment on the pesticides bioavailability; iii) classify the pesticides by the environmental risk in the aquatic ecosystem; iv) evaluate the pesticides residues concentrations in the water during acute and chronic toxicity tests for tilapia; v) evaluate the potential for leaching and runoff of both pesticides; vi) verify the toxic effects of the pesticides in the liver and gill of tilapia exposed to the acute toxicity tests. The DFB is classified as practically nontoxic to L. minor, slightly toxic to H. eques and O. niloticus, and extremely toxic to D. magna. Temephos is slightly toxic to L. minor, moderately toxic to H. eques and O. niloticus, and extremely toxic to D. magna. The longer exposure of fishes at low concentrations of DFB decreases the growth of organisms, and temephos causes mortality. The temephos decreases the relative growth rate of L. minor exposed to sublethal doses. Both pesticides cause mortality to D. magna in chronic tests. The presence of sediment decreases the bioavailability of the pesticides in water of L. minor tests. DFB is classified as low environmental risk and temephos as medium risk to L. minor and fishes. To fishes, DFB is low risk, and temephos is medium risk. To D. magna, the larvicidas were high risk. Both larvicidas have medium potential for runoff and do not... (Complete abstract click electronic access below)
Mestre
41
Segues, Bénédicte. "Décontamination chimique par hydrolyse ou oxydation en milieu structuré." Toulouse 3, 1996. http://www.theses.fr/1996TOU30281.
Full textAbstract:
Les composes organophosphores et organosoufres sont couramment utilises comme insecticides ou toxiques de guerre. En 1990, 500 molecules organophosphorees etaient homologuees pour leurs utilisations agricoles et veterinaires. De plus, l'actualite recente a montre les dangers de l'utilisation de ces derives contre les populations civiles (attaque au japon du metro au gaz sarin par la secte aoum). L'objectif de notre travail a donc ete la mise au point de systemes decontaminants simples, rapides et faciles a mettre en uvre. Ces travaux ont fait l'objet de deux parties: la premiere partie, concernant la degradation par hydrolyse basique d'un modele du paraoxon montre clairement l'avantage des systemes moleculaires organises. En effet, dans ces milieux reactionnels, il est possible de solubiliser des produits insolubles dans la phase continue, de concentrer et d'orienter les substances a l'interface. La combinaison: solution micellaire aqueuse + agent activateur conduit a d'excellents resultats puisque certains melanges permettent d'hydrolyser les esters phosphoriques avec des temps de demi-reaction inferieurs a la seconde. L'usage de solutions mixtes en absence d'agents activateurs permet aussi d'ouvrir une nouvelle piste dans l'etude de la decontamination. Dans une deuxieme partie, notre etude a concerne la degradation par oxydation d'un gaz de combat soufre: l'yperite. L'oxydation de ce derive par divers agents nucleophiles, conduit generalement a deux produits le sulfoxyde et la sulfone. Cette derniere presentant encore une certaine toxicite, l'interet est donc le controle de ces reactions grace a l'utilisation de milieux mixtes organises specifiques. Nous avons effectivement montre que la combinaison: (solution micellaire + milieux mixtes) permet grace a l'utilisation d'agents oxydants particuliers: le mppm, l'oxydation selective du sulfure en sulfoxyde avec des temps de reaction inferieurs a la minute
42
Campos, Chávez Cristian, and Alcántara Abimael Palacios. "Determinación por HPLC de residuos de insecticida órganofosforado (Methamidophos) en tomates comercializados en Lima-Perú." Universidad Nacional Mayor de San Marcos. Programa Cybertesis PERÚ, 2010. http://www.cybertesis.edu.pe/sisbib/2010/campos_cc/html/index-frames.html.
Full textAbstract:
En el presente trabajo se realizó el análisis toxicológico de identificación y cuantificación de los residuos del insecticida órganofosforado METHAMIDOPHOS en 25 muestras de tomates, en tres mercados mayoristas (La Parada, 3 de Febrero y Manzanilla) y dos mercados minoristas (N° 1 – San Juan de Lurigancho y Ceres – Ate), todos ubicados en el departamento de Lima. El análisis de identificación cualitativa se realizó por Cromatografía en Capa Fina (CCF) utilizando los Rf y por Cromatografía Líquida de Alta Resolución (HPLC) utilizando los tiempos de retención. El análisis Cuantitativo se realizó por Cromatografía Líquida de Alta Resolución (HPLC), utilizando las áreas integradas de los picos en los cromatogramas obtenidos. Se determinó la presencia de Methamidophos en la totalidad de las muestras analizadas. De las 25 muestras analizadas solo una muestra (4%) perteneciente al mercado mayorista 3 de Febrero presentó una concentración máxima de 1.0369 ppm de Methamidophos excediendo el Límite Máximo Residual (LMR) para el Methamidophos en tomates según Codex Alimentarius que es de 1.0 ppm. Palabras Clave: tomate, plaguicidas, órganofosforados, Methamidophos, LMR, CCF, HPLCIn the present study was conducted toxicological analysis for the identification and quantification of the organophosphate insecticide METHAMIDOPHOS residue in 25 samples of tomatoes, three wholesale markets (La Parada, 3 de Febrero and Manzanilla) and two retail markets (No. 1- San Juan de Lurigancho and Ceres – Ate) , all located in the department of Lima. Qualitative identification analysis was performed by Thin Layer Chromatography (TLC) using the Rf and High-Resolution Liquid Chromatography (HPLC) using the retention times. Quantitative analysis was performed by high resolution liquid chromatography (HPLC) using the integrated areas of peaks in the chromatograms obtained. We determined the presence of Methamidophos in all samples. Of the 25 samples tested only one sample (4%) belonging to the wholesale market 3 de Febrero present a maximum concentration of 1.0369 ppm of Methamidophos exceeding the Maximum Residual Limit (MRL) for Methamidophos on tomatoes as Codex Alimentarius is 1.0 ppm. Key Words: tomato, insecticide, organophosphates, Methamidophos, MRL, TLC, HPLC
43
Suchail, Séverine. "Étude pharmacocinétique et pharmacodynamique de la létalité induite par l'imidaclopride et ses métabolites chez l'abeille domestique (Apis mellifera L. )." Lyon 1, 2001. http://www.theses.fr/2001LYO1T004.
Full text
44
Palacios, Alcántara Abimael, and Chávez Cristian Campos. "Determinación por HPLC de residuos de insecticida órganofosforado (Methamidophos) en tomates comercializados en Lima-Perú." Bachelor's thesis, Universidad Nacional Mayor de San Marcos, 2010. https://hdl.handle.net/20.500.12672/1611.
Full textAbstract:
En el presente trabajo se realizó el análisis toxicológico de identificación y cuantificación de los residuos del insecticida órganofosforado METHAMIDOPHOS en 25 muestras de tomates, en tres mercados mayoristas (La Parada, 3 de Febrero y Manzanilla) y dos mercados minoristas (N° 1 – San Juan de Lurigancho y Ceres – Ate), todos ubicados en el departamento de Lima. El análisis de identificación cualitativa se realizó por Cromatografía en Capa Fina (CCF) utilizando los Rf y por Cromatografía Líquida de Alta Resolución (HPLC) utilizando los tiempos de retención. El análisis Cuantitativo se realizó por Cromatografía Líquida de Alta Resolución (HPLC), utilizando las áreas integradas de los picos en los cromatogramas obtenidos.
Se determinó la presencia de Methamidophos en la totalidad de las muestras analizadas. De las 25 muestras analizadas solo una muestra (4%) perteneciente al mercado mayorista 3 de Febrero presentó una concentración máxima de 1.0369 ppm de Methamidophos excediendo el Límite Máximo Residual (LMR) para el Methamidophos en tomates según Codex Alimentarius que es de 1.0 ppm.
Palabras Clave: tomate, plaguicidas, órganofosforados, Methamidophos, LMR, CCF, HPLC.In the present study was conducted toxicological analysis for the identification and quantification of the organophosphate insecticide METHAMIDOPHOS residue in 25 samples of tomatoes, three wholesale markets (La Parada, 3 de Febrero and Manzanilla) and two retail markets (No. 1- San Juan de Lurigancho and Ceres – Ate) , all located in the department of Lima. Qualitative identification analysis was performed by Thin Layer Chromatography (TLC) using the Rf and High-Resolution Liquid Chromatography (HPLC) using the retention times. Quantitative analysis was performed by high resolution liquid chromatography (HPLC) using the integrated areas of peaks in the chromatograms obtained. We determined the presence of Methamidophos in all samples. Of the 25 samples tested only one sample (4%) belonging to the wholesale market 3 de Febrero present a maximum concentration of 1.0369 ppm of Methamidophos exceeding the Maximum Residual Limit (MRL) for Methamidophos on tomatoes as Codex Alimentarius is 1.0 ppm. Key Words: tomato, insecticide, organophosphates, Methamidophos, MRL, TLC, HPLC.
Tesis
45
Saldaña, Serrano Miguel Angel. "Toxicidad del insecticida fipronil en estadíos de postlarva y alevín de “Gamitana”, Colossoma macropomum (Cuvier, 1818)." Bachelor's thesis, Universidad Nacional Mayor de San Marcos, 2016. https://hdl.handle.net/20.500.12672/4909.
Full textAbstract:
Determina el grado de letalidad del insecticida Fipronil en estadíos iniciales de vida de la “Gamitana”, Colossoma macropomum bajo condiciones controladas de laboratorio. Para la prueba de toxicidad con postlarvas, se evalúa en 6 concentraciones (0.00; 0.12; 0.165; 0.21; 0.255 y 0.30 mg.L-1) y 4 repeticiones por un tiempo de 48 horas y para la prueba de toxicidad con alevinos, se evalúa en 6 concentraciones (0.00; 0.221; 0.276; 0.346; 0.432 y 0.54 mg.L-1) y 3 repeticiones por un tiempo de 96 horas. Determina valores de CL50-48h (0.217mg.L-1) y CL50-96h (0.331mg.L-1), para los estadíos de postlarva y alevín, respectivamente. Además, la máxima concentración no letal para los estadíos de postlarva y alevín es de 0.12mg.L-1 y 0.221mg.L-1 respectivamente. Los peces en estadío de postlarva bajo la acción del Fipronil muestran un comportamiento inusual, nado errático en la columna de agua, espasmos en la región del pedúnculo y aleta caudal e hiperexcitación; y los peces en estadío de alevín muestran un acelerado movimiento opercular, nado errático en la columna de agua, espasmos en la región del pedúnculo y aleta caudal e hiperexcitación. Según los valores de CL50 determinados, se considera que el insecticida Fipronil sería altamente tóxico para esta especie acuática.Tesis
46
Rodríguez, Yadira Ansoar. "Potencial tóxico e genotóxico do inseticida imidacloprido em organismos não alvos /." Rio Claro, 2016. http://hdl.handle.net/11449/143893.
Full textAbstract:
Orientador: Carmem Silvia Fontanetti ChristofolettiBanca: Paula Suares Rocha
Banca: Sarah Arana
Banca: Elaine Cristina Mathias da Silva Zacarin
Banca: Thaisa Cristina Roat
Resumo: A aplicação indiscriminada de agrotóxicos constitui uma das maiores preocupações na atualidade, sendo o Brasil um dos países que mais uso faz destes produtos. O imidacloprido (IMI) é um dos inseticidas mais utilizados no mundo, principalmente nas culturas de cana-de-açúcar, citros, algodão e café. Apesar de seus benefícios, pode apresentar potencial tóxico e genotóxico em organismos não alvo. O uso de bioindicadores permite o estudo dos possíveis riscos destas substâncias nos organismos. Entre estes, plantas superiores e organismos aquáticos são considerados excelentes para avaliar efeitos de agrotóxicos no ambiente. Neste estudo, foram avaliados os efeitos de IMI em organismos não alvos (Allium cepa, Tradescantia pallida e Oreochromis niloticus) expostos a diferentes concentrações, baseadas na aplicação deste inseticida na cultura de cana-de-açúcar, por meio de ensaios celulares e moleculares. Foram testadas concentrações equivalentes à dose do produto recomendada para esta cultura (400 g/ha), a metade (200 g/ha) para simulação da diluição natural e o dobro (800 g/ha) para simulação do uso indiscriminado. O teste de aberrações cromossômicas e de micronúcleos (MN) em A. cepa e T. pallida foram utilizados para avaliar a toxicidade e genotoxicidade. Ensaio do cometa e teste do MN em eritrócitos de O. niloticus, avaliaram danos em nível primário e cromossômico. Análise das alterações histopatológicas no fígado de O. niloticus e localização in situ das proteínas de choque térmico... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: The indiscriminate application of pesticides is a major concern nowadays, and Brazil is one of the countries which use these products heavily on agriculture. The imidacloprid (IMI) is an insecticide sold worldwide, being widely used on sugar cane, citrus, cotton and coffee crops. Despite its benefits, IMI may have potential for inducing genetic changes in non-target organisms. In this sense, the use of bioindicators like higher plants and fishes allow the assessment of possible effects and risks to the environment derived from the use of this insecticide in agriculture. In this study, we evaluated the effects of IMI on non-target organisms (Allium cepa, Tradescantia pallida and Oreochromis niloticus) exposed to different concentrations, based on the application of this insecticide in the sugarcane culture, through cellular and molecular assays. A concentration equivalent to the recommended dose of the product for this culture (400 g/ha), the half (200 g/ha) for simulation of natural dilution and double (800 g/ha) that simulates the indiscriminate use. Chromosomal aberrations and micronucleus test (MN) in A. cepa and T. pallida were analyzed for toxicity and genotoxicity study. Comet assay and MN test in O. niloticus erythrocytes assess damage to primary and chromosomal level. Analysis of histopathological changes in the O. niloticus liver and in situ localization of heat shock protein (HSP70) were analyzed by light microscopy and immunohistochemistry, respectively, were perfo... (Complete abstract click electronic access below)
Doutor
47
Vial, Alain. "Devenir en milieu hydrique de trois composés organophosphorés (Parathion, Soman, VX) et de leurs métabolites : tests bactériens de toxicité et de dégradabilité." Montpellier 1, 1989. http://www.theses.fr/1989MON13514.
Full text
48
Skandrani, Dalila. "Détermination des seuils de toxicité de divers insecticides (forme pure ou commerciale) sur cellules humaines en culture (A549, SH-SY5Y) : expression des gènes et protéines de stress (HSPs, GRPs,…)." Toulouse 3, 2006. http://www.theses.fr/2006TOU30233.
Full textAbstract:
Ce travail a eu pour but de déterminer les concentrations cytotoxiques de divers insecticides (molécule pure versus formulation commerciale) qui induisaient une inhibition de la prolifération de cellules d'origine pulmonaire (A549) ou neuronale (SH-SY5Y) et d'analyser les variations d'expression de gènes de stress par la technique des cDNA arrays et/ou des protéines (HSP, GRP) sur western blot. Il a été montré que les formulations pouvaient être jusqu'à 150 fois plus toxiques que les molécules pures. Dans les cellules A549, les insecticides ont induit une surexpression de la GRP78 et une sous-expression des HSPs. Le formetanate (pur ou commercial) a induit une surexpression des transcrits GADD153 et diverses GST et UDPGT. Le Dicarzol a induit une surexpression des transcrits SOD2 et TOP2AToxicity of several insecticides was determined in vitro on lung adenocarcinoma A549 and neuroblastoma SH-SY5Y cell lines, with the aim to find out, among stress proteins, reliable and sensitive markers of occupational or accidental exposure. Carbamates (formétanate, methomyl, pyrimicarb), organochlorines (dienochlor, endosulfan), pyrethroid (bifenthrin) and neonicotinoid (imidacloprid) insecticides were comparatively investigated either as pure chemical or as commercial formulations. Measurement of threshold concentrations (LOEC) leading to a significant decrease of the growth-rate in A549 cells showed that organochlorines were the most toxic whereas imidacloprid and methomyl were the less toxic. SH-SY5Y cells were found to be more sensitive than A549. When compared at similar concentration of active principle, commercial formulations were found to be twice to 100 times more aggressive than the respective pure active molecule. In A549, GRP78 stress protein was up-regulated by almost all the insecticides, commercial formulations being more efficient. No such effect was observed in SH-SY5Y. Conversely, cytosolic HSP72/73 stress proteins were somewhat underexpressed in all cases. .
49
Lindao, Cordova Victor Alberto. "Impacto en los niveles de colinesterasa en agricultores de tomate (Solanum Iycopersicum L.) en la localidad de San Luis, Chimborazo por efecto del uso de insecticidas organofosforados y carbamatos." Doctoral thesis, Universidad Nacional Mayor de San Marcos, 2017. https://hdl.handle.net/20.500.12672/6325.
Full textAbstract:
Publicación a texto completo no autorizada por el autorDetermina las condiciones de aplicación que afectan los niveles de colinesterasa, y que generan un riesgo neurotóxico por el uso de carbamatos y organofosforados a los agricultores de tomate. La técnica que se utiliza es la espectrofotometría. El examen de colinesterasa se realiza a los pacientes expuestos a los insecticidas organofosforados y carbamatos. Se utiliza el método cinético - espectrofotométrico (405 nm a 37°C). Mediante análisis factorial, prueba de Kruskal Wallis y de correlaciones se determina las variables que más afectan los niveles de colinesterasa. Para el análisis neurotoxicologica se aplica el cuestionario Psychologisch Neurologischeò Fragebogen (PNF) a cada uno de los agricultores, lo que nos permite determinar la presencia de alteraciones clínicas, conductuales y neurológicas de los trabajadores expuestos a plaguicidas organofosforados y carbamatos.
Tesis
50
Jacob, Cynthia Renata de Oliveira [UNESP]. "Efeitos do inseticida fipronil sobre os corpos pedunculados de operárias de Scaptotrigona postica (Hymenoptera, Apidae, Meliponini)." Universidade Estadual Paulista (UNESP), 2012. http://hdl.handle.net/11449/87720.
Full textAbstract:
Made available in DSpace on 2014-06-11T19:22:59Z (GMT). No. of bitstreams: 0
Previous issue date: 2012-04-25Bitstream added on 2014-06-13T20:10:19Z : No. of bitstreams: 1
jacob_cro_me_rcla.pdf: 1789232 bytes, checksum: 4d1aeb62cf1a6763869b8890da8b652a (MD5)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Recentemente as abelhas têm sido devidamente valorizadas como importantes polinizadoras de flores silvestres e cultivadas. A densidade populacional de muitos polinizadores tem diminuído devido, principalmente, à intensificação agrícola e ao uso de pesticidas, prejudicando os serviços de polinização. A metodologia clássica para estimar a toxicidade dos produtos químicos para insetos é determinar a dose letal média (DL50) ou a concentração letal média (CL50), podendo então estabelecer doses que sejam mais seguras aos organismos não-alvo ou benéficos. Além dos efeitos de toxicidade aguda, levando a morte das abelhas, doses subletais dos inseticidas podem provocar alterações comportamentais e fisiológicas nos indivíduos, que ao longo do tempo acarretarão em sérios prejuízos na manutenção da colônia. Um dos inseticidas amplamente utilizado é o fipronil, este atua ligando-se aos receptores do ácido gama-aminobutírico (GABA), interrompendo os canais de cloro, resultando na perda de sinalização inibitória neural. Na literatura pode-se encontrar diversos trabalhos que utilizam como modelo principal a abelha Apis mellifera, porém, é importante ressaltar a diversidade existente entre as abelhas nativas no Brasil, os meliponíneos, e sua participação na conservação da biodiversidade, assim como na polinização de áreas de cultivo, o que torna extremamente importante estudos com essa abelha. Com a finalidade de entender como o fipronil interfere morfo e fisiologicamente em abelhas sem ferrão, a região de interesse deste estudo foram os corpos pedunculados, já que estes são centros cerebrais complexos e tidos como local de convergência multisensorial. Para auxiliar no mapeamento metabólico, utilizou-se como marcador a enzima citocromo oxidase e a enzima caspase-3, técnicas utilizadas na observação de atividade neural...
A few decades the bees are considered an important indicator of high environmental sensitivity, and appreciated as important pollinators of wildflowers and cultivated. The population density of many pollinators have declined to harmful levels to pollination services manly due to agricultural intensification and the use of pesticides. The classic methodology of estimating the effects of chemicals for insects is to determine the median lethal dose (LD50) or median lethal concentration (LC50) that can then establish doses that do not harm non-target organisms or beneficial. Besides the effects of acute toxicity, leading to death bees, sublethal doses of insecticides can cause physiological and behavior changes of individuals over time, resulting in serious harm to maintain the colony. One of the widely used insecticides is fipronil, its acts by binding to gamma-aminobutyric acid (GABA) disrupting chloride channels, resulting in loss of inhibitory neural signaling. In the literature one can find several works using as main bee model Apis mellifera, however, it is important to highlight the diversity of Brazilian native bees, the stingless bees, and their participation in biodiversity conversation, as well as in the pollination of cultivated land. In order to understand how fipronil affect morpho and physiologically the stingless bee S. postica, the region of interest in this study were the mushroom bodies, since these are complex brain centers and used as a place of multisensory convergence. This work established the contact LD50 and Ingestion LC50 to the fipronil insecticide for foragers workers stingless bee Scaptotrigona postica in 0.54ng/bee and 0.24ng/μL of the food after 24 hours, respectively, confirming the high toxicity of this phenylpyrazole, in the groups submitted to contact contamination, were identify morphological... (Complete abstract click electronic access below)