Desenvolvimento e aplicação de método GC-MS/MS para análise simultânea de 17 HPAs em material particulado atmosférico

Os hidrocarbonetos policíclicos aromáticos (HPAs) estão associados ao aumento da incidência de diversos tipos de cânceres no homem. Essas moléculas são formadas principalmente na queima incompleta de matéria orgânica, sendo encontradas em todos os compartimentos ambientais. Órgãos regulamentadores das áreas ambiental e de saúde ocupacional consideram 17 HPAs como contaminantes atmosféricos prioritários. Este trabalho apresenta um método para análise simultânea destes HPAs utilizando-se a cromatografia a gás acoplada à espectrometria de massas operando no modo tandem (GC-MS/MS). Os limites de detecção e quantificação do método mostraram-se até 5 vezes inferiores aos obtidos no método GC-MS (SCAN). O método mostrou-se seletivo para análise de HPAs em extratos de amostras de material particulado atmosférico. Uma análise comparativa de dois sistemas de solventes (diclorometano/metanol 4:1 v/v e hexano/acetona 1:1 v/v) para a extração de HPAs, utilizando amostras de material particulado atmosférico, revelou que ambas as misturas de solventes possuem poder de extração semelhante. Os resultados sugerem que é possível realizar extração de HPAs de material particulado atmosférico em ultra-som com a mistura hexano/acetona (1:1), que é menos tóxica em relação à mistura diclorometano/metanol (4:1), bastante utilizada nestas análises, sem perdas significativas na exatidão do método.

Optimization of photo-polymerized sol gel monolithic stationary phases prepared in polyacrylate-coated fused-silica capillaries for capillary electrochromatography

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Comportamento fotofísico do antraceno em sistemas micro-heterogêneos argila-surfactantes-íons metálicos

Argilas constituem uma classe de complexos micro-heterogêneos e podem ser utilizados como substrato para adsorção. O seu comportamento de sorção em fase sólida intensificada pela presença de surfactantes, argilas organofílicas, é um importante fenômeno explorado pela tecnologia ambiental para a remoção de compostos orgânicos policíclicos (hidrocarbonetos aromáticos policíclicos, HPA) da água, introduzidos no ambiente por fontes antropogênicas. Este trabalho tem por objetivo estudar o comportamento fotofísico do antraceno, como modelo de HPA, em sistemas micro-heterogêneos argila-surfactantes-íons metálicos (M(II)= Cd(II), Cu(II), Hg(II), Ni(II) e Pb(II); surfactantes: CTACl; SDS; TR-X100). Os estudos foram conduzidos pelo monitoramento na mudança das propriedades de fluorescência estática e na supressão da emissão do antraceno utilizado como sonda fluorescente. Como supressores foram utilizados os cátions metálicos: Cd(II), Cu(II), Hg(II), Ni(II) e Pb(II). O perfil do espectro de fluorescência e os resultados dos ensaios de supressão da fluorescência da sonda permitiram inferir na localização do sítio de solubilização do antraceno nos sistemas micro-heterogêneos estudados e na conseqüente organização dos mesmos.

Effects of genetic polymorphisms CYP1A1, GSTM1, GSTT1 and GSTP1 on urinary 1-hydroxypyrene levels in sugarcane workers

Sugarcane workers in Brazil are exposed to various genotoxic compounds, including polycyclic aromatic hydrocarbons (PAHs), derived from an incomplete combustion process of burnt sugarcane fields. The effects of the occupational exposure to sugarcane fields burning were measured in urine samples of sugarcane workers from the northwest of the State of São Paulo when exposed (harvesting) and when non-exposed (non-harvesting). The urinary levels of 1-hydroxypyrene (1-OHP) and the influence of the genetic polymorphisms CYP1A1, GSTM1, GSTT1 and GSTP1 were evaluated. Our results showed that the 1-OHP levels were significantly higher (P < 0.0000) in the exposed sugarcane workers (0.318 mu mol mol(-1) creatinine) than in the non-exposed workers (0.035 mu mol mol(-1) creatinine). In an unvaried analysis, no influence regarding the polymorphisms was observed. However, multivariate regression analysis showed that the CYP1A1*4 polymorphism in the exposed group, and age and the GSTP1 polymorphism in the non-exposed group significantly influenced urinary 1-OHP excretion levels (P < 0.10). The same group of sugarcane workers was significantly more exposed to PAHs during the harvesting period than during the non-harvesting period. (c) 2006 Elsevier B.V. All rights reserved.

Screening and confirmation of PAHs in vegetable oil samples by use of supercritical fluid extraction in conjunction with liquid chromatography and fluorimetric detection

A fast, simple, non-destructive method for the direct screening of polycyclic aromatic hydrocarbons (PAHs) in vegetable oil samples is proposed. The method uses a supercritical fluid extraction (SFE) system coupled on-line with a fluorimetric detector to determine PAHs. This special assembly avoids the main problems encountered in the determination of PAHs in complex matrices such as vegetable oils. PAHs are selectively extracted by using silica gel in the thimble and cleaned up by passage through a C18 column. Interferences are preferentially retained by the silica gel during the SFE process while PAHs are adsorbed in the C18 column and the remainder of the matrix is sent to waste. Finally, the C18 column is purged to remove residual CO2 gas and adsorbed PAHs are recovered by desorption with a solvent. The extracts from positive samples are subsequently analyzed by liquid chromatography (LC) with fluorescence detection. The proposed method allows the confirmation of vegetable oil safety and hence provides a new tool for consumer protection. (C) 2004 Elsevier B.V. All rights reserved.

Solid-phase extraction of sugar cane soot extract for analysis by gas chromatography with flame ionisation and mass spectrometric detection

The incomplete combustion of biomass is one of the most important sources of emissions of organic compounds into the atmosphere, like polycyclic aromatic hydrocarbons (PAHs) which show genotoxic activity. Since environmental samples generally contain interferents and trace amounts of PAHs of interest, concentration and clean-up procedures are usually required prior to the final chromatographic analysis. This paper discusses the performance of Sep-Pak cartridges (silica gel and RP18) on clean-up of sugar cane soot extract. The best results were obtained with a silica Sep-Pak cartridge. The recoveries ranged from 79% (benzo[b]fluoranthene) to 113% (benzo[e]pyrene). (C) 2000 Elsevier B.V. B.V. All rights reserved.

Antioxidant activity of flavonols

In this work we use a single new electronic index to describe the antioxidant activity of the flavonols, a special class of flavonoids. We also try to predict theoretically the antioxidant activity of some yet nonisolated flavonols. © 2003 Wiley Periodicals, Inc.

Toxicogenetic monitoring in urban cities exposed to different airborne contaminants

Microparticles found in the air may be associated with organic matter that contains several compounds, such as Polycyclic Aromatic Hydrocarbons (PAHs) and nitro-PAHs, and may pose a significant risk to human health, possibly leading to DNA mutations and cancers. This study associated genotoxicity assays for evaluating human exposure with the atmospheric air of two urban areas in southern Brazil, that received different atmospheric contributions. Site 1 was under urban-industrial influence and the other was a non-industrial reference, Site 2. Organic extracts from the airborne particulate matter were tested for mutagenicity via the Salmonella/microsome assay and analyzed for PAH composition. Cells samples of people residing in these two cities were evaluated using the comet and micronucleus assay (MN).Concentrations of the individual PAHs ranged from 0.01ng/m3 (benzo[a]anthracene) to 5.08ng/m3 (benzo[ghi]perylene). As to mutagenicity analysis of airborne, Site 1 presented all the mutagenic responses, which varied from 3.2±1.22rev/m3 (TA98 no S9) to 32.6±2.05rev/m3 (TA98, S9), while Site 2 ranged from negative to minimal responses. Site 1 presented a high quantity of nitro and amino derivatives of PAHs, and peaked at 56.0±3.68rev/μg (YG1024 strain). The two groups presented very low DNA damage levels without intergroup difference. Although Site 1 presented high mutagenic responses in the air samples, high PAH levels, healthy people exposed to this environment did not show significative damage in their genetic material. However, the evaluation of different environmental and genetic damage in such population is necessary to monitor possible damages. © 2013 Elsevier Inc.

Integrated quality assessment of sediments from harbour areas in Santos-São Vicente Estuarine System, Southern Brazil

Santos-São Vicente Estuarine System is a highly populated coastal zone in Brazil and where it is located the major port of Latin America. Historically, port activities, industrial and domestic effluents discharges have constituted the main sources of contaminants to estuarine system. This study aimed to assess the recent status of sediment quality from 5 zones of Port of Santos by applying a lines-of-evidence approach through integrating results of: (1) acute toxicity of whole sediment and chronic toxicity of liquid phases; (2) grain size, organic matter, organic carbon, nitrogen, phosphorus, trace metals, polycyclic aromatic hydrocarbons, linear alkylbenzenes and butyltins; (3) benthic community descriptors. Results revealed a gradient of increasing contamination for metals and organic compounds, alongside with their geochemical carriers. Sediment liquid phases were more toxic compared to whole sediment. Low number of species and individuals indicated the impoverishment of benthic community. The use of site-specific sediment quality guidelines was more appropriate to predict sediment toxicity. The integration of results through Sediment Quality Triad approach and principal component analysis allowed observing the effects of natural stressors and dredging on sediment quality and benthic distribution. Even with recent governmental efforts to control, pollution is still relevant in Port of Santos and a threat to local ecosystems. © 2013 Elsevier Ltd.

Avaliação da toxicidade e caracterização de hidrocarbonetos presentes em águas de rios que recebem efluente de indústria petroquímica

Pós-graduação em Ciências Biológicas (Biologia Celular e Molecular) - IBRC

Avaliação do potencial genotóxico e mutagênico de águas e sedimentos do rio Guaecá, São Sebastião - SP, após impacto de oleoduto da região

Pós-graduação em Ciências Biológicas (Biologia Celular e Molecular) - IBRC

Avaliação da genotoxicidade e mutagenicidade das águas dos rios Jaguari, Atibaia e Piracicaba, na região de influência da refinaria de Paulínia - SP

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Carcinogênese quimicamente induzida por DMBA em glândulas salivares submandibulares de ratos (rattus norvegicus)

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Avaliação de apoptose induzida por extrato orgânico de material particulado atmosférico, rico em hidrocarbonetos policíclicos aromáticos, na região urbana de Araraquara durante a safra e entressafra de cana-de-açúcar

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Contamination of cachaca by pahs from storage containers

Cachaça is a distiled beverage obtained from the fermentation of sugar cane syrup that, depending on the production procedures, may be susceptible to contamination by polycyclic aromatic hydrocarbons (PAHs). These compounds present carcinogenic and/or mutagenic properties and offer a risk to human health. Sixteen PAHs were determined in cachaças that had been stored in glass bottles and in polyethylene tank by gas chromatography coupled with mass spectrometry. The quantification of the PAHs utilised an internal standard. The limits of detection and quantification varied from 0.05 to 0.10 μg L−1 and 0.20 to 0.30 μg L−1, respectively. A total PAH concentration of 51.57 μg L−1 was found in the beverages that were stored in the tank, while the concentration in the cachaça stored in glass jugs was 6.07 μg L−1. These results indicate that the polyethylene tank is a source for PAHs in cachaça.