A dengue é um dos principais problemas de Saúde Pública da atualidade. É transmitida por mosquitos do gênero Aedes, sendo a espécie Aedes aegypti o vetor responsável pela transmissão no Brasil. O principal alvo de controle da doença é seu vetor, sendo o controle químico amplamente utilizado em todas as regiões atingidas. Como forma de prevenção ou em períodos de epidemia, torna-se necessária a eliminação dos mosquitos adultos, sendo indicada a nebulização a ultrabaixo volume (UBV) a frio do organofosforado malation por meio do uso de equipamentos pulverizadores acoplados a veículos. Este inseticida utilizado pode sofrer desvios durante e após a aplicação a UBV, caracterizando-se como um potencial agente de desequilíbrio ecológico, podendo atingir e gerar efeitos danosos em organismos não alvos aquáticos e terrestres. Este trabalho teve como objetivo desenvolver e validar um método de análise para o malation em cromatografia líquida de alta eficiência e obter recuperação do inseticida em níveis aceitáveis em água e solo, avaliar seu período de dissipação e tempo de meia vida (t1/2) nestas matrizes e classificá-lo quanto à toxicidade aguda e ao risco ambiental de acordo com diferentes autores, para o microcustáceo Daphnia magna, para a minhoca Eisenia foetida, para o peixe mato grosso (Hyphessobrycon eques) e para a macrófita Lemna minor. O método foi considerado adequado para análise do malation. A recuperação obtida para água foi de 97 por cento e para solo, 96 por cento . Efeitos tóxicos decorrentes da exposição ao inseticida foram observados para todos os organismos, sendo a Daphnia magna a espécie mais sensível aos testes de toxicidade aguda, com alto risco de intoxicação ambiental oriundo do uso peridomiciliar do malation. Em solo, o composto permaneceu na superfície com t1/2 de 4,5 h e sofreu lixiviação após ocorrência de chuva, sendo detectado por até 29 dias após a aplicação. Em água, o t1/2 foi de 0,1 h em pH 9.0 não sendo mais detectado a partir do segundo dia após aplicação. Em pH 7.0 e 5.0, esse período estendeu-se por até 7 dias, sendo o t1/2 de 3,2 e 4,4 d, respectivamente. / Dengue is one of the major public health problems nowadays. It is transmitted by mosquitoes of the genus Aedes, and the Aedes aegypti specie is the vector responsible for transmission in Brazil. The main target to control the disease is its vector, and the chemical control is widely used in all affected regions. As a preventive measure or in epidemic periods, it becomes necessary to eliminate adult mosquitoes, being indicated the ultralow volume nebulization of malathion organophosphate in cold way through the use of sprinklers attached to vehicles. This used insecticide can suffer deviation during and after application ULV, characterizing itself as a potential agent of environmental imbalance, with the possibility of reach and generate harmful effects on aquatic and terrestrial non-target organisms. This work had the objective to develop and validate a method of analysis for malathion in high performance liquid chromatography and obtain recovery of insecticide in acceptable levels in water and soil, evaluate its dissipation period and half-life time in these matrices and classify it on acute toxicity and environmental risk according to different authors, to the microcrustacean Daphnia magna, to the earthworm Eisenia foetida, to the fish Hyphessobrycon eques and to the macrophyte Lemna minor. The method was considered appropriate for analysis of malathion. The obtained recovery for water was 97 per cent and for soil, 96 per cent . Toxic effects resulting from exposure to the insecticide were observed for all organisms, resulting that Daphnia magna is the most sensitive species to the acute toxicity tests, with high risk of environmental intoxication originated from malathion peridomicilary use. In soil, the compound remained on the surface with t1/2 of 4.5 h and suffered lixiviation after rain occurrence, being detected for up to 29 days after application. In water, the t1/2 was 0.1 h in pH 9.0 and was not detected from the second day after application. In pH 7.0 and 5.0, this period was extended for up to 7 days, being the t1/2 of 3.2 and 4.4 d, respectively.

A dengue é um dos principais problemas de Saúde Pública da atualidade. É transmitida por mosquitos do gênero Aedes, sendo a espécie Aedes aegypti o vetor responsável pela transmissão no Brasil. O principal alvo de controle da doença é seu vetor, sendo o controle químico amplamente utilizado em todas as regiões atingidas. Como forma de prevenção ou em períodos de epidemia, torna-se necessária a eliminação dos mosquitos adultos, sendo indicada a nebulização a ultrabaixo volume (UBV) a frio do organofosforado malation por meio do uso de equipamentos pulverizadores acoplados a veículos. Este inseticida utilizado pode sofrer desvios durante e após a aplicação a UBV, caracterizando-se como um potencial agente de desequilíbrio ecológico, podendo atingir e gerar efeitos danosos em organismos não alvos aquáticos e terrestres. Este trabalho teve como objetivo desenvolver e validar um método de análise para o malation em cromatografia líquida de alta eficiência e obter recuperação do inseticida em níveis aceitáveis em água e solo, avaliar seu período de dissipação e tempo de meia vida (t1/2) nestas matrizes e classificá-lo quanto à toxicidade aguda e ao risco ambiental de acordo com diferentes autores, para o microcustáceo Daphnia magna, para a minhoca Eisenia foetida, para o peixe mato grosso (Hyphessobrycon eques) e para a macrófita Lemna minor. O método foi considerado adequado para análise do malation. A recuperação obtida para água foi de 97 por cento e para solo, 96 por cento . Efeitos tóxicos decorrentes da exposição ao inseticida foram observados para todos os organismos, sendo a Daphnia magna a espécie mais sensível aos testes de toxicidade aguda, com alto risco de intoxicação ambiental oriundo do uso peridomiciliar do malation. Em solo, o composto permaneceu na superfície com t1/2 de 4,5 h e sofreu lixiviação após ocorrência de chuva, sendo detectado por até 29 dias após a aplicação. Em água, o t1/2 foi de 0,1 h em pH 9.0 não sendo mais detectado a partir do segundo dia após aplicação. Em pH 7.0 e 5.0, esse período estendeu-se por até 7 dias, sendo o t1/2 de 3,2 e 4,4 d, respectivamente. / Dengue is one of the major public health problems nowadays. It is transmitted by mosquitoes of the genus Aedes, and the Aedes aegypti specie is the vector responsible for transmission in Brazil. The main target to control the disease is its vector, and the chemical control is widely used in all affected regions. As a preventive measure or in epidemic periods, it becomes necessary to eliminate adult mosquitoes, being indicated the ultralow volume nebulization of malathion organophosphate in cold way through the use of sprinklers attached to vehicles. This used insecticide can suffer deviation during and after application ULV, characterizing itself as a potential agent of environmental imbalance, with the possibility of reach and generate harmful effects on aquatic and terrestrial non-target organisms. This work had the objective to develop and validate a method of analysis for malathion in high performance liquid chromatography and obtain recovery of insecticide in acceptable levels in water and soil, evaluate its dissipation period and half-life time in these matrices and classify it on acute toxicity and environmental risk according to different authors, to the microcrustacean Daphnia magna, to the earthworm Eisenia foetida, to the fish Hyphessobrycon eques and to the macrophyte Lemna minor. The method was considered appropriate for analysis of malathion. The obtained recovery for water was 97 per cent and for soil, 96 per cent . Toxic effects resulting from exposure to the insecticide were observed for all organisms, resulting that Daphnia magna is the most sensitive species to the acute toxicity tests, with high risk of environmental intoxication originated from malathion peridomicilary use. In soil, the compound remained on the surface with t1/2 of 4.5 h and suffered lixiviation after rain occurrence, being detected for up to 29 days after application. In water, the t1/2 was 0.1 h in pH 9.0 and was not detected from the second day after application. In pH 7.0 and 5.0, this period was extended for up to 7 days, being the t1/2 of 3.2 and 4.4 d, respectively.

Detection of organic molecules present on the surface of dust particles is important in homeland security, agriculture, and several other applications. The research presented reports the ability of the aerosol mass spectrometer (AMS) to detect molecules on the surface of dust particles without detecting the particle core. Experiments were carried out to detect semi-volatile organic compounds adsorbed onto the surface of particulates without interference from the dust particle core. Methyl salicylate, oleic acid, and organophosphorus pesticides such as Malathion were detected on the surface of particles representative of dust-type materials. Zeolite powders were used as aerosol support, representative of a typical silica mineral aerosol present in the atmosphere. Mass spectral fingerprint information was gained by first directly detecting atomized species to record their clean electron impact mass spectrum. This facilitated detection during later experiments of organic molecules coated on an inorganic support. Spectra obtained give mass spectrometric signatures of molecules coated on inorganic particles without detection of the particle core. An important feature of the AMS is the ability to equate an ion rate detected in the mass spectrometer to a mass concentration of a given chemical species in a sample using its ionization efficiency. Based on an average inlet flow rate of 1.2 cm 3sec -1 the ionization efficiencies obtained were 5.89x10-5, 1.15x10-6, and 1.62x10-5 for Malathion, methyl salicylate, and oleic acid, respectively. These experiments and the results obtained show that detection and characterization of organic species adsorbed onto inorganic dust particles are possible at µg m-3 concentrations using the AMS.

Thesis (Ph. D.)--University of California, Riverside, 2009. / Includes abstract. Includes bibliographical references. Issued in print and online. Available via ProQuest Digital Dissertations.

Thesis (Ph. D.)--University of Wisconsin--Madison, 1971. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

Submitted by NICOLI PAGANOTI DE MELLO null (nicolimello@hotmail.com) on 2018-03-19T15:34:29Z No. of bitstreams: 1 DISSERTAÇÃO - Definitivo 19.03.18 REPOSITORIO UNESP.pdf: 1710134 bytes, checksum: c4009220773e58f60e852752b7b03cf5 (MD5) / Approved for entry into archive by Alexandra Maria Donadon Lusser Segali null (alexmar@fcav.unesp.br) on 2018-03-19T17:24:34Z (GMT) No. of bitstreams: 1 mello_np_me_jabo.pdf: 1710134 bytes, checksum: c4009220773e58f60e852752b7b03cf5 (MD5) / Made available in DSpace on 2018-03-19T17:24:34Z (GMT). No. of bitstreams: 1 mello_np_me_jabo.pdf: 1710134 bytes, checksum: c4009220773e58f60e852752b7b03cf5 (MD5) Previous issue date: 2018-02-26 / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Objetivou-se determinar a CL50-24h e classificar o malathion (Komvektor 44% EW) pela toxicidade aguda para tilápias (Oreochromis niloticus); determinar as concentrações na água que resultam em aproximadamente 10, 30, 50 e 70% de mortalidade das tilápias após 24h de exposição aguda; observar os sinais clínicos e alterações histológicas causadas pelo malathion nos peixes sobreviventes em 15 e 30 dias de recuperação; registrar as alterações nas variáveis de qualidade de água; e determinar a porcentagem de mortalidade dos peixes do lote em que os animais sobreviventes se recuperam da intoxicação aguda com o malathion. Os valores da CL50-24h do malathion e as concentrações que causam entorno de 10, 30, 50 e 70% de mortalidade dos peixes foram calculados com os dados de ensaios de toxicidade aguda em laboratório. O ensaio de recuperação dos peixes expostos por 24h às concentrações parcialmente letais foi realizado com lotes de animais em mesocosmos de 1.000 L e o de recuperação dos animais sobreviventes às intoxicações em mesocosmos de 150 L. Os sinais clínicos da intoxicação nos sobreviventes foram observados e as análises histopatológicas feitas em fragmentos de brânquias, fígado e rim coletados 24h após intoxicação aguda e aos 15º e 30º dias de recuperação. As variáveis de qualidade da água foram aferidas. A CL50-24h do malathion foi 5,15 mg.L-1, que o classifica como moderadamente e muito tóxico. As concentrações de 3,0; 4,5; 5,0 e 7,0 mg.L-1 de malathion causam,respectivamente,mortalidades de 17,5%, 27,5%, 45% e 55% dos peixes expostos em laboratório e 7,5%, 21%, 44,5% e 63,67% em mesocosmo. O malathion causa nas tilápias: letargia, secreção de muco, natação errática, mudança na pigmentação da pele, aumento do batimento opercular, espasmos musculares e perda da capacidade de arfagem.Nas brânquias, causa hiperplasia, fusão lamelar, congestão do seio venoso e desarranjo lamelar. No fígado, causa congestão dos sinusóides, deslocamento nuclear, esteatose e desarranjo cordonal. No rim, causa vacuolização das células dos túbulos renais, infiltrado inflamatório e aumento do espaço de Bowman. Os peixes se recuperam das alterações nos três tecidos em 30 dias. O malathion não altera a qualidade da água. As tilápias sobreviventes a mortalidade de 70% do lote se recuperam das alterações causadas pela exposição aguda ao malathion. / The aim of this study was to determine the LC50-24h and to classify the malathion (Komvektor 44% EW) according with acute toxicity to tilapias (Oreochromis niloticus); to determine the concentrations in the water wich caused 10, 30, 50 and 70% of mortality in tilapia after 24h of acute exposition; to observe the clinical signs and histological changes caused by malathion in surviving fish in 15 and 30 days of recovery; to register the changes in the parameters of water quality caused by malathion; and to determine the percentage of mortality in the surviving groups recover from acute intoxication by malathion. The LC50-24h values of the malathion to tilapias and the concentrations that cause about 10, 30, 50 and 70% of fish mortality was calculated with the acute toxicity dates in laboratory. The recovery test of exposed fish for 24h at partially lethal concentrations was carried out with groups of animals in mesocosm of 1000L and the recovery of the animals surviving to intoxication in mesocosm of 150L. Clinical signs of intoxication in survival fish was observed and the histologic analysis in tissue fragments of gills, liver and kidney collected after 24h acute intoxication at 15 and 30 days of recovery. The water quality parameters were recorded. The LC50-24h of malathion was 5,15 mg.L-1, and this value is classified in moderate and very toxic. The concentrations of 3,0; 4,5; 5,0 and 7,0 mg.L-1 caused, respectively, mortalities of 17,5%, 27,5%, 45% and 55% of fish in laboratory and 7,5%, 21%, 44,5% and 63,67% in mesocosm. The effect of the malathion in tilapias were: lethargy, mucus secretion, erratic swimming, change in skin pigmentation, increase of opercular beating, muscle spasms and loss of pitching capacity. In the gills, it causes hyperplasia, lamellar fusion, venous sinus congestion and lamellar derangement. In the liver, it causes congestion of sinusoids, nuclear displacement, steatosis and cordonal derangement. In the kidney, it causes vacuolization of the renal tubule cells, inflammatory infiltrate and Bowman’s space increase. The fish recovered from alterations in the three tissues in 30 days. The malathion does not change the water quality. The surviving tilapia from de group with 70% mortality rate recovered from alterations caused by acute exposition of malathion.

Submitted by ANGELA APARECIDA MACHADO null (angela_machado88@hotmail.com) on 2017-06-22T17:56:12Z No. of bitstreams: 1 TESE FINALCOMPLETA (1).pdf: 2503861 bytes, checksum: 9a7280db7b189e7bcd34f3e6e7935274 (MD5) / Approved for entry into archive by Luiz Galeffi (luizgaleffi@gmail.com) on 2017-06-22T18:03:11Z (GMT) No. of bitstreams: 1 machado_aa_dr_jabo.pdf: 2503861 bytes, checksum: 9a7280db7b189e7bcd34f3e6e7935274 (MD5) / Made available in DSpace on 2017-06-22T18:03:11Z (GMT). No. of bitstreams: 1 machado_aa_dr_jabo.pdf: 2503861 bytes, checksum: 9a7280db7b189e7bcd34f3e6e7935274 (MD5) Previous issue date: 2017-04-19 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Os equipamentos de proteção individual (EPIs) hidro-repelentes contra agrotóxicos são comercializados legalmente após a emissão do certificado de aprovação (CA). Os EPIs são avaliados inicialmente pelo ensaio de penetração de soluções aquosas. Os trabalhadores estão usando EPIs com CA aprovado com soluções aquosas em nebulização da solução oleosa de malathion diluído em óleo de soja para o controle químico do mosquito da dengue. Portanto, objetiva-se conferir a aprovação de um conjunto de EPI hidro-repelente contra agrotóxicos com certificado de aprovação (CA) para 30 ciclos de higienização; determinar a penetração, a retenção e a repelência das soluções teste e de malathion no material e nas costuras, e a permeação no material impermeável do conjunto de EPIs submetidos a diferentes procedimentos e número de usos e lavagens; validar o procedimento do ensaio de corpo inteiro adaptado para avaliar quantitativamente a penetração de líquido pulverizado; avaliar a eficiência do conjunto de EPI hidro-repelente no controle da exposição dérmica quantitativamente com o procedimento de corpo inteiro ora adaptado; e propor classes de eficácia e classificar o conjunto de EPIs pela eficácia no controle da exposição dérmica avaliada quantitativamente. Em laboratório, os conjuntos de EPIs foram lavados em uma máquina de cilindro horizontal, marca Eletrolux, modelo FOM 71 CLS. Em condições de campo, foram lavados em máquina automática, da marca Colormaq, modelo Turbo, do tipo tanquinho para 10 kg. Os EPI foram lavados por 10, 20 e 30 ciclos antes das avaliações. A solução teste aquosa foi composta com 5 % de glyphosate (Roundup® Original). As soluções de nebulização foram compostas com 5% de malathion em solução aquosa (Konvektor® EW 440) e oleosa (Fyfanon®). Na conferência do CA, o conjunto de EPI é reprovado mesmo sem nenhum ciclo de higienização devido à penetração na costura rebatida dupla maior que 5% (critério de aprovação <5%). No material hidro-repelente e nas costuras dos conjuntos de EPI, após diferentes procedimentos e número de usos e lavagens, a solução aquosa de malathion penetra e retém mais que a solução teste e a solução oleosa menos que as demais, a solução aquosa de malathion repele menos que as demais no material e na costura simples e mais na costura rebatida dupla. A penetração e a retenção das soluções no material e nas costuras aumentam e a repelência diminui com o aumento no número de usos e lavagens. O material impermeável nas pernas da calça é eficiente até 30 usos e lavagens do conjunto de EPI. O método de ensaio adaptado com o manequim é valido para quantificar a penetração de líquido pulverizado. O conjunto de EPI é eficaz para o controle da exposição dérmica sem e após 30 usos e lavagens em condições de campo e lavagens e passado e não passado com ferro quente em condições de laboratório. O uso em nebulização do malathion reduz e as lavagens em laboratório não reduz a eficácia do conjunto de EPI no controle da exposição dérmica. As classes propostas são adequadas para classificar os conjuntos de EPIs pela eficácia no controle da exposição dérmica. O conjunto de EPI se classifica na classe 1 (Efic > 95%). / Personal protective equipments (PPEs) water repellent against pesticides are legally commercialized after the approval certificate (AC) has been issued. PPEs are evaluated initially by the penetration test of aqueous solutions. Workers are using PPEs with AC approved with aqueous solutions in nebulization of the oily solution of malathion diluted in soybean oil for the chemical control of the dengue mosquito. Therefore, it is proposed to check the approval of a water repellent against pesticides set of PPE with a certificate of approval (AC) for 30 cycles of sanitation; to determine the penetration, retention and repellence of the test solutions and malathion in the material and the seams, and permeation in the PPEs set impermeable material which was submitted to different procedures and number of uses and washes; validate the whole body assay procedure adapted to evaluate quantitatively the penetration of sprayed liquid; evaluate the efficiency of the water repellent PPE pool in the control of the dermal exposure quantitatively with the whole body procedure adapted; and to propose efficacy classes and to classify the PPEs set by the effectiveness in the quantitatively evaluated dermal exposure control. In the laboratory, the PPEs sets were washed in a horizontal cylinder machine, Eletrolux brand, FOM 71 CLS model. In field conditions, it was washed in an automatic machine, Colormaq brand, Turbo model, for 10 kg. The PPEs were washed for 10, 20 and 30 cycles before the evaluations. The aqueous test solution was composed by 5% glyphosate (Roundup® Original). The nebulization solutions were composed by 5% malathion in aqueous solution (Konvektor® EW 440) and oily (Fyfanon® ). At the AC conference, the PPE set is disapproved even without any sanitizing cycle due to penetration at double folded seam of greater than 5% (approval criterion <5%). In the water repellent material and in the seams of the PPE set, after different procedures and number of uses and washes, the aqueous solution of malathion penetrates and holds more than the test solution and the oily solution less than the others. The aqueous solution of malathion repels less than the others in the material and in the simple sewing and more in the double folded seam. The penetration and retention of the solutions in the material and in the seams increase and the repellency decreases with the increase in the number of uses and washes. The waterproof material on the pant legs is efficient up to 30 uses and washes the PPE set. The test method adapted with the manikin is valid to quantify the penetration of sprayed liquid. The PPE set is effective to control dermal exposure without and after 30 uses and washes under field conditions, and washes and past and not past with hot iron under laboratory conditions. The nebulizing use of malathion reduces and laboratory washes do not reduce the effectiveness of the PPE set in controlling dermal exposure. The proposed classes are suitable to classify the PPEs sets by their efficiency in the dermal exposure control. The EPI set is classified as class 1 (Efic> 95%).

The immunotoxic effects of multiple pesticide exposure were evaluated. C57BL/6 mouse thymocytes were exposed to lindane, malathion, and permethrin, either separately or in mixtures of two pesticides, in concentrations ranging from 37.5 uM to 1mM. These exposures caused both apoptotic and necrotic cell death in thymocytes as evaluated by 7-aminoactinomycin-D, Annexin-V/PI, and lactate dehydrogenase release assays. When cells were exposed to lindane+malathion, or lindane+permethrin, a significantly greater-than-additive cytotoxicity was observed. The pesticide exposure caused DNA ladder formation with increased laddering in mixtures. Further, the effect of these pesticides on thymocyte oxidative stress was investigated. Thymocytes treated with any of these pesticides generated superoxide and H2O2. The lindane + malathion caused more-than-additive increase in superoxide production compared to single treatments of these pesticides. However, the effect of the lindane + permethrin was not significantly different from individual components of this mixture. The effects of pesticides on antioxidant enzymes were also investigated and only mixtures were found to have significant effects. Alteration in transcription factor NFkB level was measured as an indicator of oxidative stress in thymocytes following 12 h pesticide exposure, in vitro. Only lindane + malathion was found to increase the protein level. Furthermore, the effects of pesticides and their mixtures on immune functions of mice were studied in vivo. Animals (8-12 week old, male mice) were randomly divided into groups of six and injected intraperitoneally with three different doses (one-half, one-third, one-fourth, or one-eight of LD50) of individual pesticides. Exposure to individual pesticides did not alter the thymus/body or spleen/body weight ratios, thymic or splenic cell counts, or CD4/CD8 or CD45/CD90 ratios. However, anti-sRBC plaque forming cell (PFC) counts were significantly lowered with all treatments. Two other groups of animals were injected with lindane + malathion or lindane + permethrin at one-third of the LD50 of each pesticide. Exposure to pesticide mixtures did not alter the CD4/CD8 or CD45/CD90 ratios. However, the thymus/ and spleen/body weight ratios, thymic and splenic cell counts, and PFC counts were significantly lowered. These data indicate that lindane, malathion, and permethrin are immunotoxic and their mixtures can cause higher toxicity compared to individual exposures. In addition, these data support the hypothesis that oxidative stress were induced in thymocytes by exposure to these pesticides in vitro. / Ph. D.

Organophosphates (OP) such as malathion are organic derivatives of phosphoric acid with broad use in everyday life throughout the world, especially as insecticides. Lead particles can accumulate in soil and from there leach into our water supplies. Interaction with the environment offers opportunities for multiple exposures to combinations of different toxicants (such as lead and malathion). Thus, it is important to assess effects that these compounds exert not only on the nervous system, but also on the blood-brain barrier (BBB). The BBB consists of specialized endothelial cells that form the vasculature of the brain; it regulates passage of nutrients, while preventing potentially damaging substances from entering the brain. The main feature of the BBB is the presence of tight junctions between cells, which provide the BBB with its low permeability. The work presented in this dissertation tests the hypothesis that lead and malathion disrupt BBB integrity by affecting tight junctions of the BBB. The hypothesis suggests that disruptions involve changes in protein levels and gene expression as well as activation of transient receptor potential canonical channels (TRPC) that in turn increase intracellular calcium levels affecting tight junction structure. The hypothesis was tested by assessing lead-malathion interactions in an in vitro BBB model. This model was constructed with rat astrocytes and rat brain endothelial cells (RBE4). Assessments of cell toxicity in response to different concentrations of the neurotoxicants tested showed that concentrations between 10-5 µM and 10-6 µM were ideal to assess combinations of neurotoxicants. In general, protein levels of occludin, claudin 5, ZO1, and ZO2 decreased at all times, however, qPCR analysis of gene expression for all the proteins did not correlate with the assessments on protein levels. TRPC channel protein levels increased in response to neurotoxicant insult, which correlated with results for gene expression. This study suggests that at least one of the mechanisms that neurotoxicants lead and malathion utilize to disrupt permeability of the BBB is by affecting tight junction structure. This effect could be regulated by increases in gene expression of TRPC1 and TRPC4 that are associated with increases in the number of TRPC channels on the membrane of endothelial cells of the cerebral microvasculature. / Ph. D.

L’objectif de ce travail a consisté à évaluer différents effets écotoxiques de la deltaméthrine et du malathion sur trois souches du crustacé cladocère Daphnia magna. Deux de ces 3 souches appartiennent au même clone A (souches 1 et 3), ce qui a permis d’observer des différences de sensibilité inter- et intra-clonale. Les tests d’écotoxicité aiguë (48h) ont révélé, aussi bien pour la deltaméthrine que pour le malathion, que la souche 1 est plus sensible que la souche 2, elle-même plus sensible que la souche 3. Les tests chroniques (21 jours) ont montré que le critère commun majoritairement affecté par les deux pesticides est le nombre de nouveaux nés par adulte. Ces tests ont confirmé la sensibilité de la souche 1. La deltaméthrine et le malathion sont embryotoxiques puisque l’exposition des daphnies aux fortes concentrations de deltaméthrine et de malathion a induit des malformations. Pour ces effets, la souche 1 est également plus sensible que la souche 2, elle-même plus sensible que la souche 3. Nous avons aussi observé l’apparition de mâles, mais uniquement dans la descendance de la souche 1 exposée à la deltaméthrine. Le dosage de l’activité spécifique de l’acétylcholinestérase (AChE), pour les deux insecticides, a montré une inversion de l’ordre de sensibilité des souches. L’AChE, biomarqueur d’exposition et d’effet, peut être donc considérée aussi comme biomarqueur de susceptibilité. L’analyse protéomique a permis de révéler plusieurs cibles cellulaires de la deltaméthrine chez la souche 1 par rapport à la souche 2. Elle est surtout venue confirmer la plus grande sensibilité de la souche 1 par rapport à la souche 2. L’ensemble de ces résultats rappelle que le facteur génétique est une source de variation et souligne les perspectives offertes par l’analyse protéomique / The aim of this work was to evaluate different ecotoxic effects of deltamethrin and malathion on three strains of the cladoceran Daphnia magna. Two of the three strains belong to the same clone A (strains 1 and 3), which allowed to observe differences in inter-and intra-clonal sensitivity. The acute ecotoxicity tests (48h) showed for both deltamethrin and malathion, that one strain is more sensitive than strain 2, itself more sensitive than strain 3. Chronic tests (21days) showed that the common criterion mainly affected by both pesticides is the number of neonates per adult. These tests confirmed the sensitivity of the strain 1. Deltamethrin and malathion are embryotoxic as daphnid exposure to high concentrations of deltamethrin and malathion induced malformations. For these effects, strain 1 is also more sensitive than strain 2, itself more sensitive than strain 3. We also observed the appearance of males, but only in the offspring of the strain 1 exposed to deltamethrin. The determination of the specific activity of acetylcholinesterase (AChE), for both insecticides, showed a reversal of the order of susceptibility testing. Thus, as a biomarker of exposure and effect, AChE can also be considered as a biomarker of susceptibility. Proteomic analysis revealed several cellular targets of deltamethrin in strain 1 compared to strain 2. It confirms the greater sensitivity of strain 1 compared to strain 2. All these results point out that the genetic factor is a source of variation and highlight the opportunities offered by proteomic analysis