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

Avaliação do potencial do pólen apícola como bioindicador de contaminação ambiental por agrotóxicos / Evaluation of potencial use of bee pollen as bioinidicator of environmental pesticide contamination

Oliveira, Renata Cabrera de, 1984- 08 August 2014 (has links)
Orientadores: Susanne Rath, Sonia Claudia do Nascimento de Queiroz / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Química / Made available in DSpace on 2018-08-26T03:44:24Z (GMT). No. of bitstreams: 1 Oliveira_RenataCabrerade_D.pdf: 3973991 bytes, checksum: 53109a8e29cba1ca926627e521d33fd2 (MD5) Previous issue date: 2014 / Resumo: O uso frequente e indiscriminado de agrotóxicos na agricultura tem acarretado a presença de resíduos nos alimentos e contaminação ambiental, principalmente em países com grande potencial agrícola, como o Brasil. Para avaliar a presença de resíduos de agrotóxicos no ambiente, as abelhas e os produtos apícolas têm sido apontados como potenciais bioindicadores, podendo ser utilizados para monitorar grandes áreas devido às longas distâncias percorridas. Assim sendo, o potencial do uso do pólen apícola como bioindicador da contaminação ambiental por agrotóxicos foi avaliado neste trabalho. Para isso, foi necessário desenvolver e validar um método analítico para determinação de multirresíduos em pólen apícola, utilizando cromatografia a gás acoplada à espectrometria de massas sequencial (GC-MS/MS). Para definição das condições ótimas de extração, dois processos foram avaliados: o QuEChERS, e o de partição com acetonitrila. O QuEChERS mostrou ser mais eficiente (melhor seletividade e eficiência de extração) e foi validado para a determinação de 27 agrotóxicos. Estudos de sorção mostraram que os agrotóxicos são fortemente sorvidos no pólen. Nas amostras provenientes do apiário experimental na Embrapa em Jaguariúna/SP não foram encontrados níveis quantificáveis dos agrotóxicos pesquisados, enquanto a presença de resíduos de agrotóxicos nas amostras fornecidas por apicultores de Ribeirão Preto/SP foi confirmada e quantificada. Os métodos desenvolvidos e validados mostraram ser eficientes e podem ser utilizados no monitoramento ambiental quanto à presença de resíduos de agrotóxicos. Os resultados confirmam o potencial do pólen apícola como bioindicador de contaminação ambiental por agrotóxicos / Abstract: The extensive use of pesticides in agriculture crop has led to the presence of residues in food and environmental contamination, especially in countries with great agricultural potential, such as Brazil. To assess the presence of pesticide residues in the environment, honeybees and bee products have been mentioned as potential bioindicators, which can be used to monitor large areas due to long distances travelled. Therefore, the potential use of bee pollen as a bioindicator of environmental pesticides contamination has been reported in this work. For this it was necessary to develop and validate an analytical method for the determination of multiresidues in pollen, using gas chromatography coupled to tandem mass spectrometry (GC-MS/MS). For the definition of optimum extraction conditions, two procedures were evaluated: QuEChERS, and partition with acetonitrile. The QuEChERS proved to be more efficient (improved selectivity and extraction efficiency), and was validated for the determination of 27 pesticides. Sorption studies showed that pesticides are strongly sorbed in pollen. Unquantifiable levels of pesticides surveyed were found in the samples from experimental apiary at Embrapa in Jaguariúna/SP, while the presence of pesticide residues in samples provided by apiarists from Ribeirão Preto/SP was confirmed and quantified. The validated analytical methods proved to be efficient and can be used in environmental monitoring for the presence of pesticide residues. The results confirm the potential of bee pollen as a bioindicator of environmental pesticides contamination / Doutorado / Quimica Analitica / Doutora em Ciências
2

Relevance of Ethylglucuronide as a marker of alcohol consumption : development of dosage methods and study of factors potentially affecting its production / Intérêt de l'Ethylglucuronide comme marqueur d'alcoolisation : développement de méthodes de dosage et étude des sources de variabilité de sa production

Al Saabi, Alaa 03 July 2013 (has links)
La consommation excessive d’alcool présente des risques élevés pour l’individu et pour la société ; elle est fréquemment associée à une augmentation du risque d’accidents, d’actes de violence, et peut également conduire à court et/ou à long terme à de graves maladies et à des problèmes sociaux. Dès lors, l’utilisation de marqueurs fiables permettant de détecter une consommation excessive d’alcool, ponctuelle ou chronique, s’avère nécessaire pour prévenir des conséquences néfastes de l’abus d’alcool. L’éthylglucuronide (EtG) est un marqueur d’alcoolisation utilisé en toxicologie clinique (alcoologie) et médicolégale. Par rapport aux marqueurs indirects d’alcoolisation (CDT, &#947;-GT), ce métabolite mineur de l’éthanol est très spécifique et est quantifiable dans diverses matrices biologiques. La production d’EtG est catalysée par des enzymes de la famille des UDP-glucuronosyl-transférases (UGT). Cependant, les UGT impliquées dans la glucuronoconjugaison de l'éthanol, ainsi que les sources potentielles de variabilité interindividuelle de la production d'EtG, sont encore mal connues. Nos travaux ont ainsi consisté à (1) développer et valider une méthode de dosage de l’EtG dans différentes matrices biologiques par chromatographie en phase gazeuse couplée à la spectrométrie de masse en tandem, (2) identifier les UGT humaines impliquées dans la glucuronoconjugaison de l’éthanol et étudier la contribution relative de chaque isoforme active au niveau hépatique, (3) étudier l’impact de substances fréquemment utilisées par les consommateurs d’alcool sur la production d’EtG in vitro, (4) étudier l’impact de polymorphismes génétiques fonctionnels des UGT sur la production hépatique d’EtG, et enfin (5) évaluer l’impact de la consommation de cannabis et d’autres drogues sur la production d’EtG à l’aide de prélèvements post-mortem. Ces travaux ont notamment permis de montrer que (1) l'éthanol est glucuronoconjugué principalement par le foie, puis dans une moindre mesure par les reins et par l'intestin, (2) les UGT1A9 et 2B7 sont les deux enzymes majoritairement impliquées dans la glucuronoconjugaison de l’éthanol, quel que soit l’organe considéré, (3) la morphine, la codéine, la nicotine et la cotinine n’entraînent aucune modification des taux de production d’EtG in vitro ; le lorazépam et l'oxazépam augmentent légèrement cette production (p = 0,2 et 0,065, respectivement) ; le cannabidiol inhibe la glucuronoconjugaison de l’éthanol par un mécanisme non-compétitif (CI50 = 1,17 mg/L; Ki = 3,1 mg/L), alors que le cannabinol augmente cette glucuroconjugaison de manière concentration-dépendante (p <0,05), (4) les SNP c.-900G>A affectant l’UGT2B7 et IVS1+399T>C affectant l’UGT1A9 augmentent légèrement la production d’EtG in vitro. Enfin (5) le rapport des concentrations sanguines EtG/éthanol apparaît significativement plus élevé chez des co-consommateurs de cannabis et/ou d’autres drogues que chez des consommateurs d’alcool seul. L’ensemble de ces résultats démontre l’existence de plusieurs facteurs pouvant potentiellement influencer la production d’EtG et devraient donc être pris en considération lors de l’interprétation de sa concentration in vivo. / Alcohol abuse is frequently associated with an increased risk of road accidents and violence, and can also lead to serious social and health problems. Therefore, the use of reliable markers to detect excessive punctual and/or chronic consumption of alcohol is necessary to prevent the harmful consequences of alcohol abuse. Ethylglucuronide (EtG) has been proposed as a marker of alcohol consumption in a variety of clinical and forensic contexts. Compared with the indirect markers (e.g. CDT, &#947;-GT), this minor metabolite of ethanol is very sensitive and specific, and is quantifiable in various biological matrices. It is formed by conjugation of ethanol with uridine 5’-diphosphate glucuronic acid (UDP-GA) via the action of UDP-glucuronosyltransferase (UGT) enzymes. However, the knowledge of the UGTs involved in the glucuronidation of ethanol, and the potential sources of the interindividual variability of EtG production are still not clearly established. The aims of our work were (1) to develop and validate a method for the determination of EtG in different biological matrices by gas chromatography coupled with tandem mass spectrometry, (2) to identify the human UGT isoforms involved in the glucuronidation of ethanol, and then to evaluate qualitatively and quantitatively their specific contribution in the formation of EtG, (3) to study the impact of the co-administration of drugs frequently used by ethanol consumers on the in vitro production of EtG, (4) to study the impact of functional genetic polymorphisms of two UGTs on the hepatic production of EtG, and finally (5) to study the impact of the consumption of cannabis and other drugs on the production of EtG using post-mortem samples. The main results of our study showed that (1) ethanol is primarily glucuronidated by the liver and, to a lesser extent, by kidneys, (2) UGT1A9 and 2B7 were identified as the main human UGTs involved in ethanol glucuronidation, (3) morphine, codeine, nicotine, and cotinine did not modify EtG in vitro formation rate; lorazepam and oxazepam produced a minor, but not significant, increase of EtG formation. Only cannabinol and cannabidiol significantly affected ethanol glucuronidation; cannabinol significantly increased the glucuronidation of ethanol in a concentration-dependent manner, whereas cannabidiol inhibited the glucuronoconjugaison of ethanol by a non-competitive mechanism (CI50 = 1.17 mg / L; Ki = 3.1 mg / L), (4) the SNP c.-900G>A and IVS1+399T>C affecting UGT2B7 and UGT1A9, respectively, seem to increase the in vitro production of EtG, and (5) cannabis and/or drugs consumption (mainly opioids, benzodiazepines, and paracetamol) seem to be associated with ratios of blood concentrations of EtG/ethanol significantly higher than those observed among only alcohol consumers. Taken together, these results show the existence of several factors that could potentially influence the production of EtG, and that should be taken into account when interpreting its concentration in vivo.
3

[en] DEVELOPMENT AND VALIDATION OF A METHOD FOR PESTICIDE ANALYSIS IN FOOD PRODUCE FROM THE STATE OF RIO DE JANEIRO USING GAS CHROMATOGRAPHY WITH TANDEM MASS SPECTROMETRY / [pt] IMPLEMENTAÇÃO E VALIDAÇÃO DE MÉTODO ANALÍTICO PARA A DETERMINAÇÃO DE RESÍDUOS DE AGROTÓXICOS EM ALIMENTOS PROVENIENTES DO ESTADO DO RIO DE JANEIRO POR CROMATOGRAFIA GASOSA ACOPLADA À ESPECTROMETRIA DE MASSAS TANDEM

DANIELA RODITI LACHTER 20 February 2019 (has links)
[pt] O presente trabalho envolve a implementação e validação de metodologia analítica para determinação de resíduos de agrotóxicos em amostras de alimentos provenientes do Estado do Rio de Janeiro, cujos resultados servirão para um aumento de informações de um banco de dados sobre os mesmos, bem como para o aprimoramento do sistema nacional de saúde e promoção da saúde da população. Foram analisados os agrotóxicos das classes nitrogenados e piretróides. As amostras foram coletadas no CEASA da cidade do Rio de Janeiro, uma vez que este é o principal centro distribuidor de frutas e hortaliças da cidade. As culturas escolhidas para análise foram maçã, manga, morango, pepino e tomate de mesa. Após a otimização das condições cromatográficas, metodologia de extração e validação da metodologia pelos parâmetros de curva analítica e linearidade, seletividade (efeito matriz), repetibilidade, recuperação, homocedasticidade e limite de detecção do método, as amostras foram coletadas e analisadas no período de novembro de 2016 a fevereiro de 2017. A análise foi baseada no método QuEChERS e quantificação por cromatografia gasosa acoplada a espectrometria de massas tandem, no modo de Monitoramento de Múltiplas Reações. Obteve-se um método de curta duração, inferior a vinte minutos, capaz de quantificar 41 agrotóxicos com dois monitoramentos precursor-produto para cada um dos analitos, apresentando as seguintes vantagens: rápido, econômico, fácil, efetivo, robusto e seguro. O LDM variou de 1,34 a 10,22 ng g(-1). A concentração de agrotóxicos das amostras esteve abaixo desses valores para a maioria (78 porcento dos casos) dos 41 agrotóxicos analisados. Para as culturas de tomate e pepino, os agrotóxicos quantificados estiveram próximos aos seus respectivos limites de detecção. Para a manga, observaram-se alguns picos de maior concentração para o propargito e lambda-cialotrina. O primeiro de uso não autorizado pela ANVISA e o segundo, embora presente, abaixo do limite estabelecido por esta agência. As culturas de maçã e morango apresentaram a maior contaminação por agrotóxicos (38 e 44 porcento acima do LDM, respectivamente), muitos não autorizados pela ANVISA. Por ser um centro de grande distribuição de alimentos, a CEASA é suprida por diferentes fornecedores, sendo assim a variabilidade das fontes de alimentos coletados é muito grande e, portanto, a continuidade desta sistemática de avaliação torna-se necessária. / [en] The present work regards the implementation and validation of a method for analysis of pesticide residues in produce from the state of Rio de Janeiro for the improvement of the national health system. Pyrethroids and triazines class pesticides were analyzed for this research. The samples were collected at CEASA in the city of Rio de Janeiro, since it is the main fruit and vegetable distribution center in the city. The produce chosen for the analyses were apple, mango, strawberry, cucumber and tomato. After optimization of the chromatographic conditions, extraction methodology and evaluation of the parameters linearity, selectivity (matrix effect), repeatability, recovery, homocedasticity and limits of detection of the method, the samples were collected, from November 2016 to February 2017. The QuEChERS method was used for the extraction of pesticide residues and the PSA method was used for the purification of extracts, both in triplicates. The extracts were analyzed by gas chromatography with tandem mass spectrometry in Selected Reaction Monitoring mode (Multiple Reaction Monitoring). A short run method was achieved for the determination of 41 pesticides with two precursor-product for each analyte. The analitycal method showed several advantages - quick, cheap, easy, effective, rugged and safe. The detection limits were 1,34 ng/g and 10,22 ng/g. The majority of the pesticides analysed (78 per cent) were below this result. For tomato and cucumber, the only quantified compounds were close to their respective detection limits. For the analysis of mango pesticides, some peaks of higher concentration for propargite and lambda-cyhalothrin were observed. The first one is not authorized by ANVISA and the second, although present, was found below the limit established by this agency. The apple and strawberry crops showed the highest contamination by pesticides (38 and 444 per cent, respectively), many of which were not authorized by ANVISA. CEASA is a large food distribution center, so it is supplied by different distributers. The variability of the sources of food collected is very large. A more representative study on the quality of food would require a higher number of samples with a higher frequency of sampling.
4

Determinação multirresíduo de agrotóxicos em água empregando microextração líquido-líquido dispersiva (DLLME) E GC-MS/MS / Multiresidue determination of pesticides in water using dispersive liquid-liquid microextration (DLLME) e GC-MS/MS

Floss, Vagner Medeiros 19 June 2015 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The use of pesticides is related to effectiveness in pest control, as well as productivity in food production in agriculture. However, the use of these substances in high amounts is directly affecting water resources, essential for the maintenance of human life. In Brazil, the Ministry of Health through Ordinance 2914, as well as the Secretariat of the Rio Grande do Sul State Health, by Ordinance 320, stipulate maximum permissible values (VMPs) for pesticides in water. Thus, rapid, sensitive, efficient and generate small amounts of toxic waste analytical methods should be developed to determine the presence and concentration of pesticides and other chemicals in water in order to ensure they are in accordance with current legislation. This study aimed to optimize and validate an analytical method aiming at the extraction and determination of residues of 32 pesticides in water samples by applying the DLLME technical and quantification by gas chromatography coupled to Mass Spectrometry in Triple Quadrupole series (GC-MS / MS). We evaluated the different extractor solvents and dispersor, different volumes of solvents, addition salts, pH variation and time of agitation. The results were satisfactory, with recovery values between 71 and 113% for the tested levels. The coefficients of determination for the curves drawn in the matrix, presented values between 0.9900 to 0.9996. Precision data for the methodology were satisfactory, with values between 1 and 13%. The intermediate precision was RSD values in the range of 5 to 15%, with recoveries in the range 70 to 101% for the level of 0.25 ug L-1. The method presented quantification limit of 0.1 ug L-1 providing the determination of water in pesticide residues with high reliability and security. After validation of this methodology, it was applied to real water samples, in order to evaluate the method developed. / O uso de agrotóxicos se relaciona com a efetividade no controle de pragas, como também com a produtividade na produção de alimentos na agricultura. Porem, o uso dessas substâncias em altas quantidades vem afetando diretamente os recursos hídricos, essenciais para a manutenção da vida humana. No Brasil, o Ministério da Saúde através da Portaria 2914, como também, a Secretaria da Saúde do Estado do Rio Grande do Sul, pela Portaria 320, estipulam valores máximos permitidos (VMPs) para agrotóxicos em água. Dessa forma, métodos analiticos rápidos, sensíveis, eficientes e que geram pequenos volumes de resíduos tóxicos, devem ser desenvolvidos para a determinação de resíduos de agrotóxicos e demais substâncias químicas em água afim de verificar se estão de acordo com as legislações vigentes. Este estudo teve por objetivo otimizar e validar um método analítico visando a extração e determinação de resíduos de 32 agrotóxicos em amostras de água, aplicando a técnica DLLME e quantificação por Cromatografia Gasosa acoplada a Espectrometria de Massas em série com analisador do tipo Triplo Quadrupolo (GC-MS/MS). Foram avaliados diferentes solventes extratores e dispersores, volumes de solventes, adição de sais, variação do pH e tempo de agitação. Os resultados obtidos foram satisfatórios, apresentando valores de recuperação entre 71 e 113 % para os níveis avaliados. Os coeficientes de determinação para as curvas extraídas, apresentaram valores entre 0,99 e 0,9996. Os resultados de precisão do metodologia foram satisfatórios, apresentando valores entre de 1 e 13 %. A precisão intermediária apresentou valores de RSD situados na faixa de 5 e 15 %, com recuperações na faixa de 70 à 101 % para o nível de 0,25 μg L-1. O método apresentou limite de quantificação 0,1 μg L-1. A determinação de resíduos de agrotóxicos em água com alta confiabilidade e segurança. Após a validação do método desenvolvido, o mesmo foi aplicado a amostras reais de água, que indicaram presença de Alacoro, Endussulfan Alfa e 4,4 DDE.
5

Determinação de resíduos de agrotóxicos no leite bovino empregando método QuEChERS modificado e GC-MS/MS / Determination of pesticide residues in cattle milk using modified QuEChERS method and GC-MS/MS

Bandeira, Danieli Daiani 26 March 2012 (has links)
For providing a balanced composition, among fresh food, the milk is considered one of the most nutritionally complete, being a product very well accepted in the market with consumers of all ages. Thus, the analysis of milk quality is great importance for consumer information and verification of the parameters required by law. Considering all the problems involving the many chemicals used for several purposes in agriculture, and the possibility of these compounds directly or indirectly the milk and cause damage to population health, this work aimed to develope and validate a method for a multiresidue determination of 48 pesticides in cattle milk, using modified QuEChERS method and GC-MS/MS. The extraction procedure consisted of 5.0 mL of sample (milk) extracted with 5.0 mL of acetonitrile, acidified with 1% of acetic acid (v/v), followed by manual shaking for 1 min for partition step was used 2.0 g of anhydrous MgSO4 and 0.85 g of anhydrous sodium acetate. Manual agitation was repeated for 1 min, and subsequently it was performed centrifugation at 3400 rpm for 8 min. The dispersive clean up step consisted in add 1.0 mL of supernatant extract, 150.0 mg of anhydrous MgSO4, 125.0 mg of C18 and 62.0 mg of PSA in an eppendorf tube, which was shaked in a vortex for 1 min, centrifuged at 10000 rpm for 3 min. After centrifugation, the extract was transferred to a glass insert for the injection into the GC-MS/MS system. It was evaluated the linearity, limits of detection (LOD) and quantitation (LOQ), the matrix effect, accuracy and precision of the analytical method. The method proved to be efficient, with satisfactory results for recoveries, with values in a range between 71.1 and 117.4% for 45 of the 48 compounds analyzed. RSD values lowerd than 17,3%, values of LODi and LODm ranged between 0.3 to 3.0 μg L-1 and LOQi and LOQm ranged between 1.0 to 10.0 μg L-1. The validated method was applied for the determination of residues of 45 pesticides/degradation products in samples of milk UHT. The method developed was adequate for the analysis of pesticide residues in cattle milk, as all the validation parameters were within the limits required for validation of chromatographic methods, achieving satisfactorily the objectives outlined in this paper. / Por oferecer uma composição equilibrada, o leite é considerado um dos alimentos in natura mais completos nutricionalmente, sendo um produto muito bem aceito no mercado e tendo consumidores de todas as idades. Sendo assim, a análise da qualidade do leite é de grande importância para informação do consumidor e verificação dos parâmetros exigidos pela legislação. Considerando toda a problemática envolvendo as inúmeras substâncias químicas utilizadas com finalidades diversas na agropecuária, e a possibilidade destas chegarem direta ou indiretamente até o leite e causarem danos a saúde da população, neste trabalho foi desenvolvido e validado um método multirresíduo para a determinação de 48 agrotóxicos em leite de vaca, empregando método QuEChERS modificado e GCMS/ MS. O procedimento de extração consistiu em 5,0 mL de amostra (leite integral) extraída com 5,0 mL de acetonitrila acidificada com 1% de ácido acético (v/v), seguido de agitação manual por 1 min, para a etapa de partição utilizou-se 2,0 g de MgSO4 anidro e 0,85 g de acetato de sódio. Repetiu-se a agitação manual por 1 min, e posteriormente foi realizada a etapa de centrifugação a 3400 rpm, durante 8 min. A etapa de limpeza dispersiva, consistiu em 1,0 mL de extrato sobrenadante, 150 mg de MgSO4 anidro, 125 mg de C18 e 62 mg de PSA em tubo eppendorf, os quais foram agitados em vortex por 1 min centrifugados a 10000 rpm por 3 min. Após a centrifugação, o extrato foi transferido para o insert de vidro para injeção no sistema GC-MS/MS. Avaliou-se a linearidade, os limites de detecção (LOD) e quantificação (LOQ), o efeito matriz, a exatidão e a precisão do método analítico. O método demonstrou ser eficiente, apresentando resultados satisfatórios para recuperações, as quais se situaram na faixa entre 71,1 e 117,4%, para 45 dos 48 compostos avaliados, com valores de RSD ≤ 17,3%, os valores de LODi bem como o LODm variaram entre 0,3 e 3,0 μg L-1 e o LOQi e o LOQm variaram entre 1,0 e 10 μg L-1. O método validado foi aplicado para a determinação de resíduos de 45 agrotóxicos/produtos de degradação em amostras de leite UHT. O método desenvolvido mostrou-se adequado a análise de resíduos de agrotóxicos em leite, pois todos os parâmetros de validação encontraram-se dentro dos limites exigidos para validação de métodos cromatográficos, atendendo satisfatoriamente os objetivos traçados neste trabalho.
6

Método multirresíduo para agrotóxicos e compostos relacionados em ar empregando trapeamento em sorvente polimérico / Multiresidue method for pesticides and related compounds in air using no polymeric sorbent trapping

Martel, Samile 25 October 2013 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / While pesticides are applied to crops in order to control pests and thereby increase productivity, these substances can undergo processes such as volatilization, dispersion and transport, reaching the atmosphere, soil and water. Thus, this study aimed to develop and validate a method for the determination of 48 pesticides and related compounds in air, based on active sampling using a trapping device home-made, with subsequent solvent extraction of analytes and determination by Gas Chromatography coupled to Tandem Mass Spectrometry (GC-MS/MS), as well as demonstrate the applicability of the proposed method in local storage and marketing of these compounds, checking the exposure of workers. The sampling system consists of a vacuum pump to force the passage of air through the traps and a flow meter for controlling the volume of air sampled. Whereas various compounds studied have medium volatility, it was used a heater for heating the first trap, where the spike process is carried out with the compounds under study. A set of three traps glass with dimensions of 12.5 cm long x 3 mm inner diameter x 5 mm external diameter, connected by silicone connectors, complete the device used. It was used the 24 factorial design for optimization of sampling and elution, where conditions were defined as: flow of 87.5 mL min-1 sampling time of 8 h, volume of acetone for elution of 5 mL and greenhouse temperature of 60 ºC. The extract was filtered and analyzed by GC-MS/MS. The accuracy and precision of the method was verified with recovery tests of at least three concentration levels for each analyte, yielding values between 70.0 and 120.0% for most of the compounds evaluated. Most RSD values lower than 20% ensured the precision of the method. Method LOQ values were 3.0 or 6.0 μg m-3, depending on the analyte, considered appropriate to control the exposure of these compounds in air. The method was applied in company that stores and sells pesticides and in the standards preparation room in laboratory of analysis of pesticides residue, in which no residues were found for the studied compounds. The sampling and elution method proposed was effective for most compounds and can be applied in the determination of pesticides and related compounds in air samples. / Enquanto agrotóxicos são aplicados em lavouras com o intuito de controlar pragas e, consequentemente, aumentar a produtividade, essas substâncias podem sofrer processos como volatilização, dispersão e transporte, atingindo a atmosfera, solo e água. Assim, o presente trabalho teve como objetivo principal desenvolver e validar um método para a determinação de 48 agrotóxicos e compostos relacionados em ar, baseado na amostragem ativa utilizando um dispositivo de trapeamento home-made, com posterior extração dos analitos com solvente e determinação por Cromatografia Gasosa acoplada à Espectrometria de Massas em Série (GC-MS/MS), bem como demonstrar a aplicabilidade do método proposto em locais de armazenamento e comercialização destes compostos, verificando a exposição dos trabalhadores. O sistema de amostragem consiste de uma bomba de vácuo para forçar a passagem do ar pelos traps e um medidor de vazão para controle do volume de ar amostrado. Considerando que vários compostos estudados possuem média volatilidade, utilizou-se uma estufa para aquecimento do primeiro trap, onde é realizada a fortificação com os compostos em estudo. Um conjunto de três traps de vidro com dimensões de 12,5 cm de comprimento x 3 mm de diâmetro interno x 5 mm de diâmetro externo, conectados por meio de conectores de silicone, completam o dispositivo utilizado. Utilizou-se o planejamento fatorial 24 para otimização do método de amostragem e eluição, onde as condições definidas foram: vazão de 87,5 mL min-1, tempo de amostragem de 8 h, volume de acetona para eluição de 5 mL e temperatura da estufa de 60 ºC. O extrato foi filtrado e analisado por GC-MS/MS. A exatidão e precisão do método foram verificadas com ensaios de recuperação de no mínimo três níveis de concentração para cada analito, obtendo-se valores entre 70,0 e 120,0% para a maioria dos compostos avaliados. A maioria dos valores de RSD inferiores a 20% garantiram a precisão do método. Valores de LOQ do método foram de 3,0 ou 6,0 μg m-3, dependendo do analito, considerado adequado para o controle de exposição desses compostos em ar. O método foi aplicado em empresa que armazena e comercializa agrotóxicos e em ambiente de preparo de padrões em laboratório de análises de resíduos de agrotóxicos. Não foram encontrados resíduos dos compostos estudados nos locais amostrados. O método de amostragem e eluição proposto mostrou ser eficaz para a maioria dos compostos, podendo ser aplicado na determinação de agrotóxicos e compostos relacionados em amostras de ar.
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Development of analytical methods of the contamination of water by PAHs and pesticides along the Basin of "Abou Ali" River in North Lebanon / Développement des méthodes analytiques pour l'évaluation de la contamination des eaux en HAPs et pesticides le long du bassin versant du fleuve "Abou Ali" du Liban nord

Jabali, Yasmine 04 December 2017 (has links)
La pollution de l'eau est l'une des menaces écologiques les plus sérieuses au niveau des pays industrialisés et des pays en cours de développement. Les polluants sont rejetés directement ou indirectement dans les ressources en eau telles que les rivières, les lacs, les aquifères et les eaux côtières sans prétraitement approprié ; transformant ainsi nos systèmes aquatiques en un dépotoir fortement pollué par des contaminants toxiques et persistants tels que les contaminants organiques. Les hydrocarbures Aromatiques Polycycliques (HAPs) et les pesticides sont parmi les polluants organiques les plus périlleux que l'on retrouve à l’état de traces dans les milieux aquatiques. Pour cette raison, leur analyse nécessite une procédure d'extraction suivie de méthodes analytiques très sensibles et spécifiques. Dans ce contexte, le travail de cette thèse a porté en premier lieu sur le développement de deux méthodes analytiques distinctes. La première a été consacrée à l'extraction et à l'analyse des 16 HAPs prioritaires classés par l’agence de protection de l’environnement (EPA) dans. Dans cette méthode, nous nous sommes concentrés sur l'optimisation et la validation des paramètres de la spectrométrie de masse en tandem (MS / MS) afin de réduire le bruit de fond. La deuxième méthode était dédiée à l'analyse de quarante-huit pesticides dans l'eau. Dans cette méthode, les paramètres de la micro-extraction sur phase solide (SPME) et de la chromatographie en phase gazeuse couplée à la spectrométrie de masse en tandem GC-MS / MS ont été optimisés et validés. Les deux méthodes se sont révélées très sensibles, précises et sélectives pour l'analyse de ces deux familles de contaminants organiques. La deuxième partie de cette thèse était dirigée sur l'évaluation de la qualité de l'eau le long du bassin versant de la rivière Abou Ali en termes de contamination par les HAPs et les pesticides. Pour ce faire, les méthodes précédemment développées et optimisées ont été utilisées pour l'analyse. Les résultats obtenus pour les échantillons d'eau de surface ont révélés une contamination considérable par les HAPs et les pesticides à différents endroits le long du bassin versant. Cependant, pour les échantillons d'eau souterraine, aucune ou très faible concentration de HAPs et de pesticides n'a été détectée. Cette étude est la première de son genre concernant l'analyse des HAPs et des pesticides dans la zone étudiée. Elle donne un aperçu global de la qualité de l'eau le long du bassin versant et insiste sur l'importance de réaliser des mesures continues afin d'avoir une base de données complète non seulement pour la zone d'étude ou le Liban nord mais pour toutes les régions du territoire libanais. / Water pollution is one of the most thoughtful ecological threat imperiling the industrial and developing countries. Pollutants are released directly or indirectly into water resources such as rivers, lakes, aquifers and coastline waters without any suitable pre-treatment; thus transforming our aquatic systems into a dumpsite heavily polluted with toxic and persistent contaminants such as organic contaminants. Polycyclic Aromatics Hydrocarbons (PAHs) and pesticides are among the most perilous organic pollutants that are found in trace levels in aquatic environments. For this reason, their analysis requires an extraction procedure followed by highly sensitive and specific analytical methods. In this context, this work has focused, as a first step, on the development of two separate analytical methods. The first one was dedicated to the extraction and analysis of the 16 priority PAHs in water, listed by the environmental protection agency (EPA). In this method, we have focused on the optimization and validation of tandem mass spectrometry (MS/MS) parameters in order to reduce background noise. The second method was for the analysis of 48 pesticides in water where the solid-phase micro-extraction (SPME) and gas chromatography tandem mass-spectrometry GC-MS/MS parameters were optimized and validated. Both methods were found to be highly sensitive, precise and selective for the analysis of these two families of organic contaminants. As for the second part of this work, the assessment of the water quality along the watershed of Abou Ali River, in terms of its contamination by PAHs and pesticides, was performed. For this aim, the previously developed and optimized methods were used for the analysis. The results obtained for surface water samples revealed a considerable contamination by PAHs and pesticides in different locations along the watershed. However, for groundwater samples no or very low concentrations of PAHs and pesticides were detected. This study is the first of its kind concerning the analysis of PAHs and pesticides in the studied area. It provided an overview of the water quality along the watershed and stressed on the importance to do ongoing measurements in order to have a complete database not only for the studied area or the North of Lebanon, but for all the regions in the Lebanese territory.
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Développements méthodologiques pour l’extraction et l’analyse des polluants organiques d’intérêt pour l’environnement marin : application aux hydrocarbures aromatiques polycycliques

Kanan, Rami 20 December 2012 (has links)
La présence d’hydrocarbures dans l’environnement que ce soit suite à un déversement accidentel de pétrole en mer ou suite à des apports chroniques, est une préoccupation majeure en raison de leur écotoxicité et de leur potentiel à être bioaccumulés, et ainsi, pénétrer la chaîne alimentaire. Par conséquent, ces molécules sont sous haute surveillance et il est nécessaire de disposer de méthodes analytiques permettant de les identifier et de les quantifier, et ceci, pour des concentrations allant du mg/L au ng/L. Cependant et dans la plupart des cas, les analyses en laboratoire des hydrocarbures, notamment aromatiques, se limitent à la quantification des 16 hydrocarbures aromatiques polycycliques (HAP) identifiés par l’Agence américaine de Protection Environnementale (US-EPA) comme étant dangereux pour l’environnement du fait de leur caractère cancérigène. Or, les hydrocarbures aromatiques polycycliques soufrés (HAPS) ainsi que leurs homologues substitués sont, sur le plan chimique, structurellement proches des HAP, et peuvent donc présenter des risques environnementaux similaires, à savoir être cancérigènes ou mutagènes. Le travail de recherche réalisé s’inscrit dans ce contexte avec pour objectif des développements méthodologiques permettant l’extraction et l’analyse d’une gamme plus large de HAP, des HAPS et leurs dérivés alkylés directement dans les produits pétroliers ou dissous en phase aqueuse. Des protocoles d’extraction par "stir bar sorptive extraction" (SBSE) et par microextraction sur phase solide (SPME), et des méthodes d’analyse par chromatographie en phase gazeuse couplée à la spectrométrie de masse simple (GC-MS) et en tandem (GC-MS-MS) ont été développés. Les résultats obtenus plaident en faveur de ces méthodologies aussi bien en termes de linéarité de la réponse qu’en termes de sensibilité, méthodologies qui ont été appliquées avec succès pour la détermination des analytes d’intérêt dans des fractions solubles préparées au laboratoire (WAF et WSF). Pour la CG-MS-MS, si elle se révèle particulièrement adaptée car elle apporte un degré de certitude élevé, elle n’en reste pas moins une technique délicate à mettre en oeuvre, notamment dans le cas des composés alkylés pour lesquels des solutions étalons ne sont pas disponibles. Pour pallier cette difficulté, un produit de référence contenant l’ensemble des analytes d’intérêt a été caractérisé. Pour les composés alkylés non disponibles commercialement, des appro-ximations ont été effectuées par MS simple en se basant sur une analyse comparée des coefficients de réponse en mode MRM et SIM. La méthodologie ainsi mise au point a permis de caractériser le fioul de l’Erika avec une faible variabilité des résultats. Ce produit peut servir de référence pour l’analyse quantitative de l’ensemble des familles de composés identifiés dans cette étude. / The presence of hydrocarbons in the environment either as a result of oil spills at sea or due to chronic discharge is a major concern because of their ecotoxicity and their potential to bioaccumulate and thus enter the food chain. Therefore, these molecules are closely monitored and reliable analytical methods are required to identify and quantify them, for concentrations ranging from mg/L to ng/L. However, in most cases, laboratory analyses of hydrocarbons, especially aromatic hydrocarbons, are limited to the quantification of 16 polycyclic aromatic hydrocarbons (PAHs) identified by the U.S. Environmental Protection Agency (U.S. EPA) as hazardous to the environment due to their carcinogenic nature. However, polycyclic aromatic sulphur heterocycles (PASHs) and their substituted homologs are, in chemical terms, structurally similar to PAHs, and therefore can pose similar environmental risks, i.e. they can be carcinogenic or mutagenic. In this context, the research work carried out aims to develop methodologies for the extraction and analysis of a wider range of PAHs, PASHs and their alkyl derivatives directly in oil or dissolved in the aqueous phase. Extraction protocols by stir bar sorptive extraction (SBSE) and solid phase microextraction (SPME), and methods of analysis by gas chromatography coupled with mass spectrometry (GC-MS) and with tandem mass spectrometry (GC-MS-MS) have been developed. The results argue in favor of these methodologies both in terms of linearity of the response and in terms of sensitivity. These methodologies that have been successfully applied for the determination of analytes of interest in the water accommodated fraction and water soluble fraction prepared in the laboratory (WAF and WSF). For GC-MS-MS, while it is particularly suitable because it provides an additional level of selectivity, it is a difficult technique to implement, in particular in the case of molecules for which no calibration solutions are available. To overcome this difficulty, a reference oil containing all the target molecules was characterized. For alkylated compounds that are not commercially available, approximations were made by simple MS, based on comparative analysis of response coefficients in MRM (Multiple Reaction Monitoring) and SIM (Single Ion Monitoring) modes. The finalized method was used to characterize the Erika fuel oil, with low variability in the results. This product can be used as a reference for the quantitative analysis of all the families of molecules identified in this study.
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Avaliação da presença do 3-monocloro-1,2-propanediol e glicidol em óleos vegetais comestíveis utilizando GC/MS/MS e seu risco toxicológico / Evaluation of the presence of 3-monochloro-1,2-propanediol and glycidol in edible vegetable oils using GC/MS/MS and its toxicological risk

Renata Aparecida Cerqueira Tonelotto 06 February 2019 (has links)
Cloropropanóis são um grupo conhecido de contaminantes relacionados ao processamento de alimentos. Eles são formados na reação entre lipídeos e cloretos quando submetidos ao tratamento térmico, e podem ser encontrados na forma livre ou ligada. O 3-monocloro-1,2-propanediol (3-MCPD), é classificado pela IARC como possível carcinógeno humano (grupo 2B). O glicidol (e seus ésteres), é classificado também pela IARC como uma substância provavelmente carcinogênica para seres humanos (grupo 2A), e, recentemente, vem sendo encontrado em alimentos. O objetivo deste trabalho foi avaliar a presença do 3-MCPD e do glicidol em óleos vegetais comestíveis utilizando a cromatografia gasosa com detector de massa triplo quadrupolo MS/MS. A técnica utilizada foi a preconizada pela AOCS Cd 29c-13, sendo uma análise indireta, e foi possível adaptá-la visando as determinações do 3-MCPD e glicidol através da construção de curvas de calibração e análises de amostras de referência. O método foi validado e os resultados indicaram o limite de detecção do composto 3-MCPD, de 42,4 &#181;g/kg e o limite de quantificação de 50 &#181;g/kg, e para o Glicidol indicaram o limite de detecção de 43,5 &#181;g/kg e limite de quantificação de 50 &#181;g/kg. Os resultados para 3-MCPD obtidos nos ensaios da curva de calibração e linearidade demonstraram que o método foi capaz de expressar resultados com boa linearidade (0 - 10 mg/kg , r2, = 0.9991). Os resultados obtidos nos ensaios de exatidão obedeceram aos critérios de 70 a 120% de recuperação, e ±20% de variação entre os resultados de acordo com SANTE (2017). O método em questão demonstrou ser seletivo, uma vez que não foram observados picos interferentes nos tempos de retenção dos compostos estudados. Os ensaios de precisão nos níveis baixos, médio e alto e robustez demonstraram que o método é robusto e preciso, portanto a validação foi considerada adequada ao uso pretendido. Foram analisadas 368 amostras de óleos vegetais (76 amostras de óleo de canola, 48 amostras de óleo de milho, 69 amostras de óleo de algodão, 33 amostras de óleo de palma, 10 amostras de óleo de palmiste, 50 amostras de oleína de palma, 30 amostras de óleo de soja e 51 amostras de óleo de girassol). As concentrações das amostras analisadas apresentaram resultados para 3-MCPD com valores médios entre 203 a 1205 &#181;g/kg. Para o Glicidol os valores foram de 2 a 1198 &#181;g/kg, com elevado o desvio padrão entre os resultados analíticos, onde o óleo de palma apresentou a maior variação de 1600 a 5260 &#181;g/kg. Através da avaliação do risco realizada para o composto 3-MCPD foi possível detectar, utilizando o critério do pior cenário de exposição e resultados analíticos, os valores diários de consumo de óleo de algodão de 0,044 &#181;g/kg p.c., de óleo de girassol 0,045 &#181;g/kg p.c., óleo de canola 0,18 &#181;g/kg p.c., óleo de palma de 0,28 &#181;g/p.c, óleo de milho de 0,0462 &#181;g/kg p.c., e o óleo de soja, de maior consumo no Brasil (72%) apresentou o valor de 0,27 &#181;g/kg p.c. O consumo de todos estes óleos, pela a população brasileira, pode ser considerado seguro ao comparar com o valor de TDI Ingestão Diária Tolerável - de 2&#181;g/kg p.c.. Através da avaliação do risco realizada também utilizando o critério de pior cenário de exposição e e resultados analíticos para o composto glicidol foi possível verificar que os valores diários de consumo de óleo de algodão de 0,061 &#181;g/kg p.c., de óleo de girassol 0,03 &#181;g/kg p.c., óleo de canola 0,13 &#181;g/kg p.c. e de óleo de palma de 0,57 &#181;g/p.c, de óleo de milho de 0,11 &#181;g/kg p.c, e o óleo de soja de maior consumo no Brasil (72%) não ultrapassam o valor de 0,288 &#181;g/kg p.c indicando consumo seguro destes óleos para a população brasileira baseado na TDI de 1000&#181;g/kg p.c. / Chloropropanols are a known group of contaminants related to food processing. They are formed during the reaction process between lipids and chlorides when submitted to heat treatment and can be found in free or bound form. The 3-monochloro-1,2-propanediol (3-MCPD), is classified by IARC as a possible human carcinogen (group 2B). Glycidol (and its esters), also classified by IARC as a substance likely to be carcinogenic to humans (group 2A), has recently been found in food. The present study aims to evaluate the presence of 3-MCPD and glycidol in edible vegetable oils using gas chromatography with triple quadrupole MS/MS mass detector. The technique applied is recommended by AOCS, guide Cd 29c-13, an indirect analysis, and allows quantification of 3-MCPD and glycidol by building the calibration curves and analysis of reference samples. The method was validated and the detection limit of the contaminant 3-MCPD of 42,4 &#181;g/kg and the quantification limit of 50 &#181;g/kg was established. For Glycidol the detection limit of was 43,5 &#181;g/kg and quantification limit was 50 &#181;g/kg. The results obtained in the calibration and linearity curves demonstrated that the method could express results with good linearity (0 10 mg/kg, r2, = 0.9991). The results obtained in the trueness trials agreed to the criteria of 70 to 120% of recovery, and ± 20% of variation between the results according to what is preconized by SANTE (2017). The method showed to be selective, since no interfering peaks were observed in the retention times of the studied compounds. The tests performed on low, medium and high values demonstrated the robustness and precision of the method, so the validation was considered completed and suitable for the purpose. A total of 368 vegetable oil samples were analyzed (76 samples of canola oil, 48 samples of corn oil, 69 samples of cottonseed oil, 33 samples of palm oil, 10 samples of kern palm oil, 50 samples of palm olein, 30 samples of soybean oil and 51 samples of sunflower oil). The results found in samples for 3-MCPD were within mean values between 203 and 1205 &#181;g/kg. The results found in samples for glycidol were within mean values between 2 to 1198 &#181;g/kg where palm oil presented the highest variation for glycidol from 1600 to 5260 &#181;g/kg. Through the risk assessment for the contaminant 3-MCPD it was possible to detect the values based on exposed worst case scenario and analytical results. The results for cottom oil were 0,044 &#181;g/kg bw, sunflower 0,045 &#181;g/kg bw, canola 0,18 &#181;g/kg bw and palm oil 0,28 &#181;g/kg bw, corn oil 0,0462 &#181;g/kg bw, and for soybean, which is the most consumed oil in Brazil (72%) the value of 0,27 &#181;g/kg bw. These results indicates safe consumption for these oils based in the Theoretical Daily Ingestion - TDI of 2&#181;g/kg bw. The risk assessment for the glycidol based on exposure worst case scenario and analytical results presented for cottom oil the value of 0,061 &#181;g/kg bw, sunflower 0,03 &#181;g/kg bw, canola oil 0,13 &#181;g/kg bw , palm oil 0,57 &#181;g/kg bw, corn oil 0,11 &#181;g/kg bw and for soybean, which is the most consumed in Brazil - 72% the value of 0,27 &#181;g/kg bw. These results indicates safe consumption for these oils based in the TDI of 1000&#181;g/kg bw.
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Avaliação da presença do 3-monocloro-1,2-propanediol e glicidol em óleos vegetais comestíveis utilizando GC/MS/MS e seu risco toxicológico / Evaluation of the presence of 3-monochloro-1,2-propanediol and glycidol in edible vegetable oils using GC/MS/MS and its toxicological risk

Tonelotto, Renata Aparecida Cerqueira 06 February 2019 (has links)
Cloropropanóis são um grupo conhecido de contaminantes relacionados ao processamento de alimentos. Eles são formados na reação entre lipídeos e cloretos quando submetidos ao tratamento térmico, e podem ser encontrados na forma livre ou ligada. O 3-monocloro-1,2-propanediol (3-MCPD), é classificado pela IARC como possível carcinógeno humano (grupo 2B). O glicidol (e seus ésteres), é classificado também pela IARC como uma substância provavelmente carcinogênica para seres humanos (grupo 2A), e, recentemente, vem sendo encontrado em alimentos. O objetivo deste trabalho foi avaliar a presença do 3-MCPD e do glicidol em óleos vegetais comestíveis utilizando a cromatografia gasosa com detector de massa triplo quadrupolo MS/MS. A técnica utilizada foi a preconizada pela AOCS Cd 29c-13, sendo uma análise indireta, e foi possível adaptá-la visando as determinações do 3-MCPD e glicidol através da construção de curvas de calibração e análises de amostras de referência. O método foi validado e os resultados indicaram o limite de detecção do composto 3-MCPD, de 42,4 &#181;g/kg e o limite de quantificação de 50 &#181;g/kg, e para o Glicidol indicaram o limite de detecção de 43,5 &#181;g/kg e limite de quantificação de 50 &#181;g/kg. Os resultados para 3-MCPD obtidos nos ensaios da curva de calibração e linearidade demonstraram que o método foi capaz de expressar resultados com boa linearidade (0 - 10 mg/kg , r2, = 0.9991). Os resultados obtidos nos ensaios de exatidão obedeceram aos critérios de 70 a 120% de recuperação, e ±20% de variação entre os resultados de acordo com SANTE (2017). O método em questão demonstrou ser seletivo, uma vez que não foram observados picos interferentes nos tempos de retenção dos compostos estudados. Os ensaios de precisão nos níveis baixos, médio e alto e robustez demonstraram que o método é robusto e preciso, portanto a validação foi considerada adequada ao uso pretendido. Foram analisadas 368 amostras de óleos vegetais (76 amostras de óleo de canola, 48 amostras de óleo de milho, 69 amostras de óleo de algodão, 33 amostras de óleo de palma, 10 amostras de óleo de palmiste, 50 amostras de oleína de palma, 30 amostras de óleo de soja e 51 amostras de óleo de girassol). As concentrações das amostras analisadas apresentaram resultados para 3-MCPD com valores médios entre 203 a 1205 &#181;g/kg. Para o Glicidol os valores foram de 2 a 1198 &#181;g/kg, com elevado o desvio padrão entre os resultados analíticos, onde o óleo de palma apresentou a maior variação de 1600 a 5260 &#181;g/kg. Através da avaliação do risco realizada para o composto 3-MCPD foi possível detectar, utilizando o critério do pior cenário de exposição e resultados analíticos, os valores diários de consumo de óleo de algodão de 0,044 &#181;g/kg p.c., de óleo de girassol 0,045 &#181;g/kg p.c., óleo de canola 0,18 &#181;g/kg p.c., óleo de palma de 0,28 &#181;g/p.c, óleo de milho de 0,0462 &#181;g/kg p.c., e o óleo de soja, de maior consumo no Brasil (72%) apresentou o valor de 0,27 &#181;g/kg p.c. O consumo de todos estes óleos, pela a população brasileira, pode ser considerado seguro ao comparar com o valor de TDI Ingestão Diária Tolerável - de 2&#181;g/kg p.c.. Através da avaliação do risco realizada também utilizando o critério de pior cenário de exposição e e resultados analíticos para o composto glicidol foi possível verificar que os valores diários de consumo de óleo de algodão de 0,061 &#181;g/kg p.c., de óleo de girassol 0,03 &#181;g/kg p.c., óleo de canola 0,13 &#181;g/kg p.c. e de óleo de palma de 0,57 &#181;g/p.c, de óleo de milho de 0,11 &#181;g/kg p.c, e o óleo de soja de maior consumo no Brasil (72%) não ultrapassam o valor de 0,288 &#181;g/kg p.c indicando consumo seguro destes óleos para a população brasileira baseado na TDI de 1000&#181;g/kg p.c. / Chloropropanols are a known group of contaminants related to food processing. They are formed during the reaction process between lipids and chlorides when submitted to heat treatment and can be found in free or bound form. The 3-monochloro-1,2-propanediol (3-MCPD), is classified by IARC as a possible human carcinogen (group 2B). Glycidol (and its esters), also classified by IARC as a substance likely to be carcinogenic to humans (group 2A), has recently been found in food. The present study aims to evaluate the presence of 3-MCPD and glycidol in edible vegetable oils using gas chromatography with triple quadrupole MS/MS mass detector. The technique applied is recommended by AOCS, guide Cd 29c-13, an indirect analysis, and allows quantification of 3-MCPD and glycidol by building the calibration curves and analysis of reference samples. The method was validated and the detection limit of the contaminant 3-MCPD of 42,4 &#181;g/kg and the quantification limit of 50 &#181;g/kg was established. For Glycidol the detection limit of was 43,5 &#181;g/kg and quantification limit was 50 &#181;g/kg. The results obtained in the calibration and linearity curves demonstrated that the method could express results with good linearity (0 10 mg/kg, r2, = 0.9991). The results obtained in the trueness trials agreed to the criteria of 70 to 120% of recovery, and ± 20% of variation between the results according to what is preconized by SANTE (2017). The method showed to be selective, since no interfering peaks were observed in the retention times of the studied compounds. The tests performed on low, medium and high values demonstrated the robustness and precision of the method, so the validation was considered completed and suitable for the purpose. A total of 368 vegetable oil samples were analyzed (76 samples of canola oil, 48 samples of corn oil, 69 samples of cottonseed oil, 33 samples of palm oil, 10 samples of kern palm oil, 50 samples of palm olein, 30 samples of soybean oil and 51 samples of sunflower oil). The results found in samples for 3-MCPD were within mean values between 203 and 1205 &#181;g/kg. The results found in samples for glycidol were within mean values between 2 to 1198 &#181;g/kg where palm oil presented the highest variation for glycidol from 1600 to 5260 &#181;g/kg. Through the risk assessment for the contaminant 3-MCPD it was possible to detect the values based on exposed worst case scenario and analytical results. The results for cottom oil were 0,044 &#181;g/kg bw, sunflower 0,045 &#181;g/kg bw, canola 0,18 &#181;g/kg bw and palm oil 0,28 &#181;g/kg bw, corn oil 0,0462 &#181;g/kg bw, and for soybean, which is the most consumed oil in Brazil (72%) the value of 0,27 &#181;g/kg bw. These results indicates safe consumption for these oils based in the Theoretical Daily Ingestion - TDI of 2&#181;g/kg bw. The risk assessment for the glycidol based on exposure worst case scenario and analytical results presented for cottom oil the value of 0,061 &#181;g/kg bw, sunflower 0,03 &#181;g/kg bw, canola oil 0,13 &#181;g/kg bw , palm oil 0,57 &#181;g/kg bw, corn oil 0,11 &#181;g/kg bw and for soybean, which is the most consumed in Brazil - 72% the value of 0,27 &#181;g/kg bw. These results indicates safe consumption for these oils based in the TDI of 1000&#181;g/kg bw.

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