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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
151

Análise automatizada da frequência de micronúcleos em culturas celulares expostas a agentes genotóxicos físicos e quimícos / Automated analysis of the frequency of micronuclei in cell cultures exposed to physical and chemical genotoxic agents

Carvalho, Luma Ramirez de 21 May 2019 (has links)
O ensaio de frequência de micronúcleos é uma técnica importante utilizada para avaliar danos genotóxicos de agentes químicos ou físicos (como radiação ionizante) em células, baseado na quantificação de células contendo micronúcleos, que são fragmentos derivados de DNA danificado com coloração semelhante ao dos núcleos principais, mas com 5 a 30% do seu tamanho. Tradicionalmente, este ensaio é realizado usando microscopia de coloração convencional de acordo com Giemsa, mas atualmente esta técnica está sendo atualizada para uma abordagem automatizada que se baseia na dissolução da membrana plasmática por detergentes levando em conta apenas núcleos e micronúcleos com seu DNA corados por corantes fluorescentes, que pode discriminar núcleos de células viáveis dos das células inviáveis e permite a contagem por citometria de fluxo. Este trabalho avaliou a extensão de dano genotóxico radioinduzido por radiação gama (60Co) em doses entre 0,5 e 16Gy, e o potencial genotóxico de três peptídeos utilizados em medicina nuclear (PSMA-617, PSMA-11 e Ubiquicidina 29-41). As membranas celulares foram lisadas na presença dos corantes SYTOX® Green e EMA, e núcleos marcados com os dois fluorocromos foram considerados provenientes de células inviáveis e, portanto, removidos da análise. As quantidades de micronúcleos (porcentagem de eventos) nas amostras, foram proporcionais às doses de radiação, e puderam ser ajustadas a um modelo linear-quadrático (R2 = 0,993). Somente doses mais altas (8 e 16 Gy) e controles positivos induziram aumentos relevantes nas quantidades de micronúcleos. Os radiofármacos foram testados com concentrações de 0,1x, x, 10x e 100x a concentração utilizada em adultos, e não induziram dano em concentrações praticáveis. / The micronucleus frequency assay is an important technique used to evaluate genotoxic damage of chemical or physical agents (such as ionizing radiation) in cells, based on the quantification of micronucleus-containing cells, which are fragments derived from damaged DNA with similar coloration to of the main nuclei, but with 5 to 30% of its size. Traditionally, this assay is performed using conventional staining microscopy according to Giemsa, but currently this technique is being updated to an automated approach that relies on the dissolution of the plasma membrane by detergents taking into account only nuclei and micronuclei with their DNA stained by dyes fluorescence, which can discriminate nuclei from unviable or living cells and allows counting by flow cytometry. The genotoxic potential of three peptides used in nuclear medicine (PSMA-617, PSMA-11 and Ubiquicidine 29-41) was evaluated by gamma radiation (60Co) at doses in the range among 0.5 and 16Gy. Cell membranes were lysed in the presence of the SYTOX® Green and EMA dyes, and cores labeled with the two fluorochromes were considered to be from non-viable cells and therefore removed from the analysis. The amount of micronucleus (percentage of events) in the samples was proportional to the radiation doses, and could be adjusted to a linear-quadratic model (R2 = 0.993). Only higher doses (8 and 16 Gy) and positive control induced significant increases in micronucleus amounts. Radiopharmaceuticals were tested at concentrations of 0.1x, 1x, 10x, and 100x the concentration used in adults, and did not induce damage at feasible concentrations.
152

Aspectos tecnológicos da síntese da petidina / Technological approach for petidine synthesis

Bronislaw Polakiewicz 19 June 1990 (has links)
As rotas sintéticas para obtenção de cloridrato de petidina foram avaliadas sob o ponto de vista tecnológico, material e de segurança com o objetivo de adaptar a produção a reatores multipropósito. O aperfeiçoamento de técnicas antigas e introdução de técnicas recentes como a catálise de transferência de fase viabilizaram o projeto. / The synthetic routes for obtention of pethidine hydrochloride were evaluated under technologycal, material and safety aproach, in order to be able to manufacturing in multipurpose reactors. The improvment of old techniques and introduction of recents advances like phase transfer catalysis \"P.T.C.\" making it a available presentation.
153

Estudo dos efeitos ecotoxicológicos dos fármacos paracetamol e dipirona sódica para organismos aquáticos / Ecotoxicological study of effects of the pharmaceuticals dipyrone sodium and paracetamol to aquatic organisms

Lameira, Vanessa 29 October 2012 (has links)
O presente estudo avaliou os efeitos letais e subletais de dipirona sódica e paracetamol para organismos de água doce. O efeito letal foi determinado pela realização de ensaios agudos com D. similis, C. dubia, C. silvestrii e D. rerio. A influência da temperatura, tipo de água de diluição e fotoperíodo na ecotoxicidade aguda foram avaliadas. Os efeitos subletais foram determinados por meio de ensaios de embrioxicidade com D. similis (20°C), crônicos individuais e populacionais com D. similis, C. dubia e C. silvestrii. A influência da temperatura na ecotoxicidade crônica individual e populacional foi determinada. Os critérios para aceitabilidade para o controle (número de neonatas) nos ensaios populacionais com D. simlis (20 e 25°C) e C. dubia, foram estabelecidos. Nos ensaios de ecotoxicidade aguda, D. similis (20°C) foi mais sensível a dipirona sódica que a 25°C e, para paracetamol, D. similis (25°C) foi mais sensível. A água de diluição influenciou na ecotoxicidade aguda apenas do paracetamol e o fotoperíodo não influenciou na ecotoxicidade aguda de ambos os fármacos. Os valores de CL(I);96H obtidos para D. rerio foram 3670 e 590mg.L-1 para dipirona sódica e paracetamol, respectivamente. Dipirona sódica e paracetamol induziram malformações nas neonatas e embriões de D. similis e os valores de CI50 obtidos foram 21,1 e 94,00mg.L-1, respectivamente. Os valores de CI50 nos ensaios crônicos individuais com dipirona sódica para D. similis (20°C e 25°C) foram 7,53mg.L e 8,08mg.L-1, respectivamente. Para C. dubia e C. silvestrii a CI50 para ensaios crônicos individuais com dipirona sódica foram 5,38 e 3,57mg.L-1, respectivamente. Nos ensaios crônicos individuais com paracetamol, a CI50 para D. similis (20°C) foi 21,84mg.L-1 e 10,72mg.L-1 para D. similis (25°C). Para C. dubia e C. silvestrii a CI50 nos ensaios crônicos individuais com paracetamol foram 7,24 e 4,15mg.L-1, respectivamente. Como critérios de aceitabilidade para os ensaios crônicos populacionais estabeleceu-se para o controle de D. similis (20 e 25°C) e C. dubia 137, 143 e 80 neonatas, respectivamente. Os valores de CI50 nos ensaios populacionais com D. similis (20 e 25°C), C. dubia e C. silvestrii para dipirona sódica foram 8,84, 10,82, 4,68 e 2,81mg.L-1, respectivamente. Para os ensaios populacionais com paracetamol os valores de CI50 para D. similis (20 e 25°C), C. dubia e C. silvestrii foram 9,57, 10,1, 6,48 e 4,26mg.L-1, respectivamente. Os valores das concentrações que causaram ecotoxicidade aguda e crônica não são superiores as concentrações destes compostos no ambiente porém, de acordo com a classificação baseada na Diretiva Européia 93/67/EEC, estes compostos são classificados como nocivos para o ambiente. / The present study evaluated the lethal and sublethal effects of dipyrone and paracetamol to different freshwater organisms. The lethal effect was determined by acute toxicity assays with D. similis, C. dubia, C. silvestrii and Danio rerio. The influence of temperature, type of dilution water and photoperiod were evaluated in acute toxicity assays. The sublethal effects were determined by Embryotoxicity with D. similis (20°C) and chronic toxicity assays both individual and population methods with D. similis, C. dubia and C. silvestrii. The influence of temperature upon individual and population chronic ecotoxicity was also determined. The criteria for acceptability for the population control assays with D. simlis (20 and 25°C) and C. dubia were established. D.similis (20°C) was more sensitive for dipyrone that 25 °C and for paracetamol, D.similis (25°C) was more sensitive. Dilution water interfere on acute ecotoxicity paracetamol, only and the photoperiod did not influence the acute ecotoxicity of both drugs. The LC(I);96H to Danio rerio was 3670mg.L-1 and 590mg.L-1 for dipyrone and paracetamol, respectively. Dipyrone and paracetamol induced malformations in D. similis neonates and embryos. The IC50 for these assays with dipyrone were 21,1mg.L-1 and 94mg.L-1 for tests with paracetamol. The IC50 of dipyrone to D. similis (20°C) was 7,53 and 8,08 at 25°C. Values of IC50 to C. dubia and C. silvestrii on individual chronic toxicity tests with dipyrona was 5,98 and 3,57mg.L-1respectively. The IC50 of paracetamol for D. similis (20°C) was 21,84 and 10,72mg.L-1 for at 25°C in individual chronic tests. The IC50 to C. dubia and C. silvestrii in individual chronic tests with paracetamol was 7,24 and 4,15mg.L-1 respectively. As criteria of acceptability for the population chronic tests were established to control the D. similis (20 and 25°C) and C. dubia, 137, 143 and 80 respectively. The IC50 obtained to D. similis (20 and 25°C), C.dubia and C.silvestrii for Dipyrone 8,84; 10,82; 4,68 and 2,81mg.L-1 respectively. For chronic population tests with paracetamol the IC50 to D. similis with 20 and 25°C, C.dubia and C.silvestrii was 9,57; 10,1; 6,48 and 4,26mg.L-1 respectively. The concentrations that cause acute and chronic ecotoxicity on organisms in this study are higher than environmental concentrations of these compounds. However, according to the classification based on the European Directive 93/67/EEC, these compounds are hazardous to the environment.
154

Aspectos tecnológicos da síntese da petidina / Technological approach for petidine synthesis

Polakiewicz, Bronislaw 19 June 1990 (has links)
As rotas sintéticas para obtenção de cloridrato de petidina foram avaliadas sob o ponto de vista tecnológico, material e de segurança com o objetivo de adaptar a produção a reatores multipropósito. O aperfeiçoamento de técnicas antigas e introdução de técnicas recentes como a catálise de transferência de fase viabilizaram o projeto. / The synthetic routes for obtention of pethidine hydrochloride were evaluated under technologycal, material and safety aproach, in order to be able to manufacturing in multipurpose reactors. The improvment of old techniques and introduction of recents advances like phase transfer catalysis \"P.T.C.\" making it a available presentation.
155

Desenvolvimento de um curso à distância e análise de sua efetividade na capacitação de farmacêuticos para a dispensação de medicamentos (Pharmacists in dispensing drugs - PharmDisp) / Development of a distance course and analysis of its effectiveness in the training of pharmacists for dispensing drugs (Pharmacists in dispensing drugs - Pharm Disp).

Reis, Tiago Marques dos 04 August 2016 (has links)
A dispensação é um serviço farmacêutico importante para a promoção do uso correto dos medicamentos, prevenção de agravos à saúde e alcance de resultados satisfatórios da farmacoterapia. Entretanto, para que essa prática seja realizada adequadamente, é necessário que o farmacêutico esteja devidamente capacitado e possua conhecimento sobre fisiopatologia, terapêutica e legislação sanitária para subsidiar a relação com o paciente e com outros profissionais da saúde. Apesar disso, uma pesquisa revelou que 78,6% dos farmacêuticos não possuem conhecimento satisfatório para a realização da dispensação e mais da metade dos profissionais apontam a falta de tempo e recursos como obstáculo para a participação em cursos de capacitação presenciais. Buscando, então, intervir sobre os resultados da pesquisa citada, o presente estudo teve como objetivo avaliar a efetividade de um curso à distância na capacitação de farmacêuticos para a prática da dispensação de medicamentos. O estudo do tipo experimental teve como população farmacêuticos comunitários de todo o país. Desenvolveu-se um curso de capacitação na plataforma Moodle, no qual foi abordada a dispensação de medicamentos no tratamento das doenças crônicas não transmissíveis mais prevalentes no Brasil (hipertensão arterial sistêmica, diabetes mellitus, dislipidemias e asma). Um questionário foi elaborado e validado para mensurar o conhecimento dos participantes em dois momentos distintos: antes (baseline) e após (endpoint) o curso. Além disso, foram avaliados: i) a satisfação dos participantes em relação ao modelo de capacitação proposto, por meio de um questionário específico; ii) a prática da dispensação pelos farmacêuticos de Ribeirão Preto - SP selecionados para participar do curso, por meio da técnica do paciente simulado. Os resultados indicam que o curso foi efetivo na capacitação dos profissionais (p < 0,05), embora não tenha sido percebido no endpoint um melhor desempenho em relação à prática da dispensação entre os farmacêuticos que participaram da avaliação pelo paciente simulado. Apesar disso, os profissionais se mostraram satisfeitos com relação ao curso. Como conclusão, verificou-se que um curso à distância é efetivo para capacitar farmacêuticos em relação à dispensação de medicamentos, mas também permitiu atestar que essa estratégia não é suficiente para tornar satisfatória a realização do serviço. Atividades práticas que desenvolvam a performance e as condutas dos profissionais devem ser exploradas ao longo da capacitação. Todavia, o farmacêutico precisa também assumir posturas mais adequadas durante a dispensação, não permitindo que as pressões de mercado interfiram sobre a qualidade do seu serviço. / The dispensing drugs is an important pharmaceutical service to promote the rational use of drugs and so it is possible to prevent health problems and achieve satisfactory results of pharmacotherapy. However, for this practice to be properly carried out, it is necessary that the pharmacist is properly trained and have knowledge about pathophysiology, treatments and health legislation to support the relationship with the patient and other health professionals. Nevertheless, a survey revealed that 78.6% of pharmacists do not have adequate knowledge to perform the dispensing drugs and more than half of these professionals point that the lack of time and resources as a barrier to participation in classroom training courses. So we seek to intervene on the results of the cited survey by this study that aimed to evaluate the effectiveness of a distance learning course in the training of pharmacists to the practice of dispensing drugs. This is a clinical trial and the study population wer community pharmacists across the country. A training course was developed in Moodle, which was addressed to dispensing drugs in the treatment of the most prevalent chronic noncommunicable in Brazil (hypertension, diabetes mellitus, dyslipidemia and asthma). A questionnaire was developed and validated to measure the knowledge of the participants at two different times: before (baseline) and after (endpoint) the course. In addition, we also evaluated: i) the satisfaction of participants in relation to the proposed training model through a specific questionnaire; ii) the practice of dispensing drugs by pharmacists of Ribeirão Preto - SP selected to attend the course, through mistery shopper technique. The results indicate that the course was effective in professional training (p <0.05), although it was not realized in endpoint better performance in the practice of dispensing pharmacists who participated in the evaluation by the mistery shopper. Nevertheless, the professionals were satisfied with the course. In conclusion, it was found that a distance course is effective to enable pharmacists in relation to the dispensing drugs, but also allowed certify that this strategy is not sufficient to render satisfactory service realization. Practical activities to develop the performance and behavior of professionals should be explored along the training. However, the pharmacist must also take more appropriate positions during the dispensation and not allow market pressures to interfere on the quality of their service.
156

The sorption fate of active pharmaceutical ingredients in soils receiving high wastewater inputs and implications for risk assessments

Lees, Katherine Edith January 2018 (has links)
Population growth, increasing affluence, and greater access to medicines have led to an increase in active pharmaceutical ingredients (APIs) entering sewerage networks. Wastewater in lower and lower middle-income countries use that use wastewater for irrigation may use untreated or poorly treated wastewater resulting in the potential for greater concentrations of APIs to enter soils in this way. Wastewater re-used for irrigation is currently not included in environmental risk assessments for APIs in soils. The addition of wastewater to soils changes the organic content and can increase the pH of soils, which will have an impact on the fate of any ionisable APIs introduced during the irrigation process. As the input of APIs to soil from wastewater irrigation is not currently included in the risk assessments, this is an area that requires increased attention. A study was undertaken using a modified sorption-desorption batch equilibrium method (OECD 106) to simulate the addition of synthetic wastewater (SWW) to soils compared to a normal OECD 106 study. The APIs studied were ofloxacin, propranolol, naproxen and nevirapine, and represent a range of API physico-chemical properties. These experiments showed that the changes to soil properties (pH and dissolved organic carbon (DOC)) caused by irrigation with SWW can change the fate of APIs in soils. The ionisation state of the API at the altered pH was more important for the positively charged propranolol than it was for the negatively charged naproxen and neutral nevirapine. The Kd and Log Koc increased during the sorption experiment in some cases with SWW. This has implications on the current terrestrial risk assessment where the trigger value for a more detailed soil risk assessment in at Log Koc >4. If the experiment is only performed in 10 mM CaCl2 as is currently required this may lead to unknown risks of APIs in wastewater irrigated soils not being taken into account. Three soil sterilisation or microbial enzyme suppression methods were investigated to identify how successful they were and if there was any impact on the soil physical chemical structure. Gamma irradiation, autoclaving and the addition of 0.2 g L-1 sodium azide were studied. None of the methods successfully sterilised the soils and some changes in soils were identified post-treatment. Autoclaving destroyed the soil structure, turning it into a fine powder and significantly increasing DOC. Sodium azide changed the pH of the loam soil but not the sandy loam soil. Literature suggested that gamma irradiation was the most likely to sterilise the soils with the least amount of disturbance to its physico-chemical properties but increases in DOC were identified in the current study. The changes to soils after sterilisation varied depending on the individual soil properties, indicating that soils should be studied on a case-by-case basis. Irrigation with wastewater provides continuous inputs of chemicals into soils throughout the growing season so it is vital that more work is done to understand the ultimate fate of pollutants in soil as a result. Wastewater has the potential to change the fate of chemicals in soils meaning that current risk assessments may not thoroughly assess all risks involved.
157

Estudo dos efeitos ecotoxicológicos dos fármacos paracetamol e dipirona sódica para organismos aquáticos / Ecotoxicological study of effects of the pharmaceuticals dipyrone sodium and paracetamol to aquatic organisms

Vanessa Lameira 29 October 2012 (has links)
O presente estudo avaliou os efeitos letais e subletais de dipirona sódica e paracetamol para organismos de água doce. O efeito letal foi determinado pela realização de ensaios agudos com D. similis, C. dubia, C. silvestrii e D. rerio. A influência da temperatura, tipo de água de diluição e fotoperíodo na ecotoxicidade aguda foram avaliadas. Os efeitos subletais foram determinados por meio de ensaios de embrioxicidade com D. similis (20°C), crônicos individuais e populacionais com D. similis, C. dubia e C. silvestrii. A influência da temperatura na ecotoxicidade crônica individual e populacional foi determinada. Os critérios para aceitabilidade para o controle (número de neonatas) nos ensaios populacionais com D. simlis (20 e 25°C) e C. dubia, foram estabelecidos. Nos ensaios de ecotoxicidade aguda, D. similis (20°C) foi mais sensível a dipirona sódica que a 25°C e, para paracetamol, D. similis (25°C) foi mais sensível. A água de diluição influenciou na ecotoxicidade aguda apenas do paracetamol e o fotoperíodo não influenciou na ecotoxicidade aguda de ambos os fármacos. Os valores de CL(I);96H obtidos para D. rerio foram 3670 e 590mg.L-1 para dipirona sódica e paracetamol, respectivamente. Dipirona sódica e paracetamol induziram malformações nas neonatas e embriões de D. similis e os valores de CI50 obtidos foram 21,1 e 94,00mg.L-1, respectivamente. Os valores de CI50 nos ensaios crônicos individuais com dipirona sódica para D. similis (20°C e 25°C) foram 7,53mg.L e 8,08mg.L-1, respectivamente. Para C. dubia e C. silvestrii a CI50 para ensaios crônicos individuais com dipirona sódica foram 5,38 e 3,57mg.L-1, respectivamente. Nos ensaios crônicos individuais com paracetamol, a CI50 para D. similis (20°C) foi 21,84mg.L-1 e 10,72mg.L-1 para D. similis (25°C). Para C. dubia e C. silvestrii a CI50 nos ensaios crônicos individuais com paracetamol foram 7,24 e 4,15mg.L-1, respectivamente. Como critérios de aceitabilidade para os ensaios crônicos populacionais estabeleceu-se para o controle de D. similis (20 e 25°C) e C. dubia 137, 143 e 80 neonatas, respectivamente. Os valores de CI50 nos ensaios populacionais com D. similis (20 e 25°C), C. dubia e C. silvestrii para dipirona sódica foram 8,84, 10,82, 4,68 e 2,81mg.L-1, respectivamente. Para os ensaios populacionais com paracetamol os valores de CI50 para D. similis (20 e 25°C), C. dubia e C. silvestrii foram 9,57, 10,1, 6,48 e 4,26mg.L-1, respectivamente. Os valores das concentrações que causaram ecotoxicidade aguda e crônica não são superiores as concentrações destes compostos no ambiente porém, de acordo com a classificação baseada na Diretiva Européia 93/67/EEC, estes compostos são classificados como nocivos para o ambiente. / The present study evaluated the lethal and sublethal effects of dipyrone and paracetamol to different freshwater organisms. The lethal effect was determined by acute toxicity assays with D. similis, C. dubia, C. silvestrii and Danio rerio. The influence of temperature, type of dilution water and photoperiod were evaluated in acute toxicity assays. The sublethal effects were determined by Embryotoxicity with D. similis (20°C) and chronic toxicity assays both individual and population methods with D. similis, C. dubia and C. silvestrii. The influence of temperature upon individual and population chronic ecotoxicity was also determined. The criteria for acceptability for the population control assays with D. simlis (20 and 25°C) and C. dubia were established. D.similis (20°C) was more sensitive for dipyrone that 25 °C and for paracetamol, D.similis (25°C) was more sensitive. Dilution water interfere on acute ecotoxicity paracetamol, only and the photoperiod did not influence the acute ecotoxicity of both drugs. The LC(I);96H to Danio rerio was 3670mg.L-1 and 590mg.L-1 for dipyrone and paracetamol, respectively. Dipyrone and paracetamol induced malformations in D. similis neonates and embryos. The IC50 for these assays with dipyrone were 21,1mg.L-1 and 94mg.L-1 for tests with paracetamol. The IC50 of dipyrone to D. similis (20°C) was 7,53 and 8,08 at 25°C. Values of IC50 to C. dubia and C. silvestrii on individual chronic toxicity tests with dipyrona was 5,98 and 3,57mg.L-1respectively. The IC50 of paracetamol for D. similis (20°C) was 21,84 and 10,72mg.L-1 for at 25°C in individual chronic tests. The IC50 to C. dubia and C. silvestrii in individual chronic tests with paracetamol was 7,24 and 4,15mg.L-1 respectively. As criteria of acceptability for the population chronic tests were established to control the D. similis (20 and 25°C) and C. dubia, 137, 143 and 80 respectively. The IC50 obtained to D. similis (20 and 25°C), C.dubia and C.silvestrii for Dipyrone 8,84; 10,82; 4,68 and 2,81mg.L-1 respectively. For chronic population tests with paracetamol the IC50 to D. similis with 20 and 25°C, C.dubia and C.silvestrii was 9,57; 10,1; 6,48 and 4,26mg.L-1 respectively. The concentrations that cause acute and chronic ecotoxicity on organisms in this study are higher than environmental concentrations of these compounds. However, according to the classification based on the European Directive 93/67/EEC, these compounds are hazardous to the environment.
158

Caractérisation de l’impact des activités humaines sur la qualité de la ressource en eau en milieu urbain sub-saharien : étude de la contamination du bassin versant de la Méfou (Région Centre du Cameroun) par les pesticides et les résidus pharmaceutiques / Characterization of human activity impacts on the quality of the water resource in urban sub-saharan africa : study of pesticide and pharmaceutical contamination of the Méfou watershed (Cameroon, Center Region)

Branchet, Perrine 23 November 2018 (has links)
En Afrique Sub-Saharienne, les problématiques de contamination de la ressource en eau par les pesticides et les résidus pharmaceutiques commencent à être mises en évidence. La problématique de la thèse porte sur la caractérisation de l’impact des activités humaines sur la qualité de la ressource en eau, par l’étude de la contamination par les pesticides et les résidus pharmaceutiques. Le site d’étude choisi est le bassin versant de la Méfou, qui draine la capitale du Cameroun, Yaoundé. Dans un premier temps, le site est caractérisé par ses spécificités environnementales (relief, occupation des sols) et sociodémographiques afin d’identifier les pressions anthropiques. Les pratiques d’agriculture urbaine, et en particulier le maraîchage intensif dans les bas-fonds entraîneraient l’utilisation massive de pesticides. L’absence d’assainissement efficace et les multiples latrines, drains et fosses septiques constitunt autant de sources diffuses de contamination par les résidus de médicaments. En prenant le cas des pesticides, une méthode cartographique a permis de confirmer l’hypothèse selon laquelle les parcelles agricoles pourraient être identifiées comme des sources de pollution diffuses de pesticides via le ruissellement. La méthode multicritère SIRIS-Pesticides de l’INERIS (Institut National de l’Environnement Industriel et des Risques) appliquée sur deux scénarios de pratiques agricoles indique un potentiel transfert des pesticides ciblés vers les eaux de surface. Afin de conforter ces hypothèses, deux diagnostics de pollution ont été réalisés entre 2015 et 2018 en saisons pluvieuses, couplant des méthodes d’échantillonnages ponctuels et passifs. Une liste de 32 pesticides et de 24 résidus pharmaceutiques a été recherchée dans les eaux de surface et les eaux souterraines du bassin de la Méfou. Les résultats généraux indiquent (i) de fortes concentrations en herbicides et en anti-inflammatoires non stéroïdiens ainsi que la détection et la quantification d’une large gamme de composés recherchés, (ii) une contamination bien plus marquée en milieu urbain qu’en milieu péri-urbain, (iii) un risque environnemental à ces concentrations pour deux herbicides (diuron et atrazine) et (iv) la contamination de certains points d’eau souterraine (forages, puits, sources) par les résidus pharmaceutiques. Une enquête sociologique réalisée autour des points d’eau de prélèvement a permis d’identifier les enjeux liés à l’utilisation de cette ressource en eau. La contamination des eaux souterraines pourrait entraîner une exposition potentielle des populations aux résidus pharmaceutiques présents dans leur eau de boisson. Les résultats principaux constituent donc une base d’information sur les pressions anthropiques, les niveaux de contamination et les enjeux liés à l’eau à Yaoundé. Ils soulèvent des questionnements sur (i) les transferts des pesticides et des résidus médicamenteux dans l’hydrosystème de la Méfou, et (ii) à propos de l’exposition et des risques sanitaires potentiels posés par leur occurrence et leurs niveaux de contamination dans la ressource en eau. / Demographic growth and urbanization create pressure on water resources. Among urban contaminants, pesticides and pharmaceuticals can be discharged into the aquatic environment through agricultural activities and untreated waste waters. Their presence is also reported in global water bodies. Measured contamination levels can have ecotoxicological effects on aquatic organisms as well as on human populations. In Sub-Saharan Africa, these problems are beginning to be highlighted. Local agricultural practices and consumption of pharmaceuticals lead to specific concerns.The aim of this thesis is to identify and characterize the impacts of human activity on the quality of the water resource in urban Sub-Saharan Africa, by analyzing pesticide and pharmaceutical contamination. The study area was the Méfou watershed that drains the political capital of Cameroon, Yaoundé (Center Region).First, the study area was characterized by its environmental (reliefs, land use) and socio-demographic specificities to identify anthropogenic pressures. Urban agricultural practices and in particular the intensive market gardening in the humid lowlands involves the use of massive amounts of pesticides. The absence of a sewage system and the numerous pit-latrines, drains and septic tanks are the sources of diffuse pharmaceutical contamination.Using the example of pesticides, a contaminated runoff mapping method based on susceptibility maps (from the IRIP method) confirmed that some treated plots located in situations that favor runoff were sources of diffuse pesticide contamination. Several areas in the study basin can accumulate this polluted runoff. Next, the multi-criteria SIRIS-Pesticides method from INERIS was applied based on two agricultural scenarios constructed with data sources from the literature. Results pointed to the potential transfer of pesticides from crops to both surface and groundwater.To reinforce these hypotheses, two water quality surveys were conducted in the rainy season between 2015 and 2018, combining grab and passive sampling. Thirty-two pesticides and twenty-four pharmaceuticals were searched for in surface and groundwater in the Méfou watershed. The main results indicate that (i) high concentrations of herbicides and analgesics were detected and quantified in the water samples along with a wide range of targeted compounds; (ii) the contamination pattern showed that the urban area is more polluted than the peri-urban area of Yaoundé; (iii) the measured concentrations pose an environmental risk, in particular the herbicides atrazine and diuron; and (iv) some groundwater sampling points used for drinking water were contaminated by the targeted pharmaceuticals.A social survey conducted in March 2018 around the sampling points identified the risks related to water use. The lack of a sewage system and the discharge of untreated waste water into the immediate surroundings facilitate contamination of the sampling sites. As groundwater is used as an alternative to the tap water network in Yaoundé, the population is also exposed to the risk of pharmaceutically contaminated drinking water.The main results provide baseline information about anthropogenic pressures, contamination levels and related issues in Yaoundé. They raise questions about (i) the transfer of contaminants in the Méfou hydrosystem and (ii) population exposure and potential health risks due to their presence and to the levels of contamination of the water resources.
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Pharmaceuticals in the Aquatic Environment: A Critical Appraisal of Uncertainty and Knowledge Gaps in Human Health Risk Assessment

Pokhrel, Lok R., Dubey, Brajesh, Scheuerman, Phillip R. 01 January 2011 (has links)
No description available.
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Pharmaceutical Waste in Vermont: Results from a Survey on Purchasing, Use & Disposal

Hart, Christine 01 January 2018 (has links)
Pharmaceutical waste is an emerging form of waste with significant impacts on the environment. This study reports the results of a state-wide phone survey on pharmaceutical purchasing, use and disposal behavior among Vermont residents (n = 421). The objectives of this study were: 1) to compare the demographic nature of populations who purchase and use medicaton to those associated with leftover medication, and 2) to evaluate the impact of disposal behavior in Vermont and to recommend strategies to minimize pollution. The findings of this study showed that approximately 93% of survey participants reported purchasing of medication, 60% reported leftover medication and 25% reported disposing of medications down-the-drain or via municipal trash, both of which are known pathways leading to environmental pollution. Results indicate that pharmaceutical waste is common in Vermont and that disposal behavior may be contributing towards pollution. The conclusion of this study is that better management of pharmaceutical waste is needed to protect the environment and public health.

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