RESUMO
This work assessed the impact of fuelling an automotive engine with palm biodiesel (pure, and two blends of 10% and 20% with diesel, B100, B10 and B20, respectively) operating under representative urban driving conditions on 17 priority polycyclic aromatic hydrocarbon (PAH) compounds, oxidative potential of ascorbic acid (OPAA), and ecotoxicity through Daphnia pulex mortality test. PM diluted with filtered fresh air (WD) gathered in a minitunel, and particulate matter (PM) collected directly from the exhaust gas stream (W/oD) were used for comparison. Results showed that PM collecting method significantly impact PAH concentration. Although all PAH appeared in both, WD and W/oD, higher concentrations were obtained in the last case. Increasing biodiesel concentration in the fuel blend decreased all PAH compounds, and those with 3 and 5 aromatic rings were the most abundant. Palm biodiesel affected both OPAA and ecotoxicity. While B10 and B20 exhibited the same rate of ascorbic acid (AA) depletion, B100 showed significant faster oxidation rate during the first four minutes and oxidized 10% more AA at the end of the test. B100 and B20 were significantly more ecotoxic than B10. The lethal concentration LC50 for B10 was 6.13 mg/L. It was concluded that palm biodiesel decreased PAH compounds, but increased the oxidative potential and ecotoxicity.
Assuntos
Poluentes Atmosféricos , Hidrocarbonetos Policíclicos Aromáticos , Poluentes Atmosféricos/análise , Poluentes Atmosféricos/toxicidade , Biocombustíveis/análise , Biocombustíveis/toxicidade , Gasolina/análise , Gasolina/toxicidade , Estresse Oxidativo , Óleo de Palmeira , Material Particulado/análise , Material Particulado/toxicidade , Hidrocarbonetos Policíclicos Aromáticos/análise , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Emissões de Veículos/análise , Emissões de Veículos/toxicidadeRESUMO
The worldwide spillage of fossil fuels causes an ever-increasing environmental concern due to their resistance to biodegradation and toxicity. The diesel fuel is one of the derivative forms of petroleum that is widely used in the world. Its composition has many aromatic compounds and long hydrocarbons chains, both persistent and hazardous, thus requiring complex microbial dynamics to achieve full biodegradation. At this point, biodiesel has advantages because it is produced from renewable sources. It also has a relatively fast biodegradation. Biodiesel formulation chemically varies according to the raw material used for its production. While vegetable oils tend to have homogeneous proportions of linoleic and oleic fatty acids, animal fats have an heterogeneous distribution of stearic, palmitic and oleic fatty acids. As some studies have already detected the toxic potential of biodiesel from vegetable oil, this study sought information on the phytotoxic and genotoxic potential of animal fat-based biodiesel and compare it with fossil fuel as diesel fuel and crude petroleum. The impacts on the microbial activity of soils contaminated with biodiesel, diesel fuel and crude petroleum were performed by the dehydrogenase activity. Phytotoxicity tests were performed with Eruca sativa seeds and genotoxicity bioassays with Allium cepa seeds. The results showed a rapid assimilation of biodiesel by the autochthonous soil microorganisms. Soil contaminated with either diesel or crude petroleum inhibited the root and hypocotyl elongation of E. sativa. Overall, petroleum contaminated soils showed higher genotoxic potential. Biodiesel from animal fat was rapidly assimilated by soil microorganisms and did not present significant phytotoxic or genotoxic potential, but significantly reduced the mitotic index of A. cepa roots. Our results showed that biodiesel from animal fat have rapid biodegradability. Biodiesel also led to less impacts during seed development and lower genotoxic potential when compared to crude petroleum and diesel fuel. In addition, biodiesel from animal fat does not present the same toxicity demonstrated by biodiesel from soybean-based biodiesel described in current literature.
Assuntos
Biocombustíveis/toxicidade , Gasolina/toxicidade , Petróleo/toxicidade , Poluentes do Solo/toxicidade , Testes de Toxicidade , Biodegradação Ambiental , Biocombustíveis/classificação , Testes de Mutagenicidade , Microbiologia do Solo , Glycine max/químicaRESUMO
Biodiesel, an alternative energy source, is promoted as cleaner and safer than other fuel options due to its reported reduction of particulate and gaseous emissions (CO2, CO, and total hydrocarbons). However, its volatile organic compounds (VOCs) and polycyclic aromatic hydrocarbon (PAHs) emissions are key to understanding its toxic, mutagenic and carcinogenic risk factors. This research was developed to assess the genotoxic impact of exhaust emissions using biodiesel from animal fat, palm oil and soybean oil blended with diesel (B80). Diluted exhaust gases were analyzed simultaneously for pollutant emissions and for toxicity using an exposure chamber called the BioToxMonitor, where Tradescantia pallida and a KU-20 clone were exposed to exhaust following Trad-MCN and Trad-SH bioassays. The results show differences in the emission compositions and considerable mutagenic potential among the three biodiesels tested, with palm oil biodiesel emissions being the least harmful, based on its low pollutant concentrations and the negative response in the TradSH bioassay. In contrast, the animal fat biodiesel and soybean oil biodiesel emissions were as toxic as the diesel emissions, being positive in both Trad bioassays. This could be related to the PAH and carbonyl concentrations found in the vehicular exhaust. The genotoxicity of diesel emissions was related to PM1 and the concentrations of both gas and particle PAHs concentrations, which were two times higher compared to the highest concentrations observed for biodiesel. The data suggest that micronucleus assays in Tradescantia pallida are more sensitive for gaseous pollutant exposure. This is the first reported study of biodiesel exhaust biomonitoring in situ and under controlled conditions inside an exposure chamber.
Assuntos
Poluentes Atmosféricos/toxicidade , Biocombustíveis/toxicidade , Dano ao DNA , Monitoramento Ambiental/métodos , Gasolina/toxicidade , Tradescantia/efeitos dos fármacos , Emissões de Veículos/toxicidade , Biocombustíveis/classificação , Testes para Micronúcleos/métodos , Tradescantia/genéticaRESUMO
In the present study, a multistage route is proposed for the treatment of biodiesel industry wastewater (BWW) containing around 1000 mg L-1 of total organic carbon (TOC), 3500 mg L-1 of chemical oxygen demand (COD), and 1325 mg L-1 of oil and grease. Initially, BWW aerobic biodegradability was assessed via Zhan-Wellens biodegradability test to confirm the appropriate treatment route. Then, a hybrid moving bed bioreactor (MBBR) system was chosen as the first treatment stage. The hybrid MBBR achieved 69 and 68% removal of COD and TOC removals, respectively, and provided great conditions for biomass growth. The bacterial community present in the hybrid MBBR was investigated by PCR-DGGE and potential biodegraders were identified such as: members of Desulfuromonadales, Nocardioidaceae and Pseudomonadaceae. Since biodegradation in the hybrid MBBR alone was unable to meet quality requirements, advanced oxidation processes, such as Fenton and photo-Fenton, were optimized for application as additional treatment stages. Physicochemical properties and acute toxicity of BWW were analyzed after the multistage routes: hybrid MBBR + Fenton, hybrid MBBR + photo-Fenton and hybrid MBBR + UV-C254nm/H2O2. Hybrid MBBR + Fenton or photo-Fenton showed overall COD removal efficiencies greater than 95% and removed acute toxicity, thus being appropriate integrated routes for the treatment of real BWW. Graphical abstract á .
Assuntos
Biocombustíveis/análise , Reatores Biológicos/microbiologia , Microbiota , Águas Residuárias/química , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Aliivibrio fischeri/efeitos dos fármacos , Biocombustíveis/efeitos da radiação , Biocombustíveis/toxicidade , Análise da Demanda Biológica de Oxigênio , Biomassa , Peróxido de Hidrogênio/química , Ferro/química , Modelos Teóricos , Oxirredução , Testes de Toxicidade Aguda , Raios Ultravioleta , Poluentes Químicos da Água/efeitos da radiação , Poluentes Químicos da Água/toxicidadeRESUMO
Contexto: O metanol é usado como matéria-prima na fabricação de biodiesel e pode causar, em especial, danos oftalmológicos e neurológicos. A exposição ocupacional acontece principalmente pela inalação de vapores. No entanto, os dados relacionados aos efeitos da exposição crônica ao metanol em humanos são limitados. Objetivos: Mostrar situações e atividades com risco de exposição ao metanol em uma planta de biodiesel e a presença de possíveis sintomas de contaminação nos trabalhadores. Métodos: Questionário, entrevistas, observação direta e análise documental possibilitaram a coleta dos dados. Resultados: O processo produtivo apresentou oito situações de exposição ao metanol. Entre os 42 sujeitos da pesquisa, 27 trabalhavam diretamente expostos e rela-taram ter dor de cabeça (71,42%), formigamento (42,00%), entre outros sintomas. As mais importantes queixas relacionadas com os efeitos neurotóxicos foram irritação (40,50%), ansiedade (35,70%) e dor de cabeça (64,30%). Funcionários das áreas administrativas também apresentavam sintomatologia idêntica à de contaminação pelo químico. Conclusões: Trabalhadores em diferentes atividades estavam expostos ao metanol, e a análise dos sintomas associados à exposição a esse solvente revelou que a maioria apresentava alguma sintomatologia compatível com a contaminação por ele.
Background: Methanol is used as raw material for biodiesel production and might cause especially visual and neurological disorders. Occupational exposure mainly occurs through vapor inhalation. However, the available data on the effects of human chronic exposure to methanol are limited. Aims: To describe situations and activities involving risk of exposure to methanol in a biodiesel plant and the possible presence of symptoms of contamination in workers. Methods: Data collection was performed by means of direct observation, interviews, document analysis and application of a questionnaire. Results: The production process included eight different situation os methanol exposure. Among the 42 participants in the study, 27 worked under conditions of direct methanol exposure and reported headache (71.42%) and tingling (42.00%) among other symptoms. The most important complaints related to the neurotoxic effects of methanol were irritation (40.50%), anxiety (35.70%) and headache (64.30%). Similarly, workers in administrative areas exhibited the same symptoms of contamination by the chemical. Conclusions: Workers performing various different activities were exposed to methanol; analysis of the symptoms associated with exposure to the solvent showed that most of them exhibited symptoms compatible with methanol contamination.
Assuntos
Riscos Ocupacionais , Metanol/toxicidade , Fontes Geradoras de Energia , Biocombustíveis/toxicidade , Poluição Ambiental , Coleta de Dados/instrumentaçãoRESUMO
Toxicological responses of exhaust emissions of biodiesel are different due to variation in methods of generation and the tested biological models. A chemical profile was generated using ICP-MS and GC-MS for the biodiesel samples obtained in Brazil. A cytotoxicity assay and cytokine secretion experiments were evaluated in human bronchial epithelial cells (BEAS-2B). Cells were exposed to polar (acetone) and nonpolar (hexane) extracts from particles obtained from fuel exhaust: fossil diesel (B5), pure soybean biodiesel (B100), soybean biodiesel with additive (B100A) and ethanol additive (EtOH). Biodiesel and its additives exhibited higher organic and inorganic constituents on particles when compared to B5. The biodiesel extracts did not exert any toxic effect at concentrations 10, 25, 50, 75, and 100µgmL(-1). In fact quite the opposite, a cell proliferation effect induced by the B100 and B100A extracts is reported. A small increase in concentrations of inflammatory mediators (Interleukin-6, IL-6; and Interleukin-8, IL-8) in the medium of biodiesel-treated cells was observed, however, no statistical difference was found. An interesting finding indicates that the presence of metals in the nonpolar (hexane) fraction of biodiesel fuel (B100) represses cytokine release in lung cells. This was revealed by the use of the metal chelator. Results suggest that metals associated with biodiesel's organic constituents might play a significant role in molecular mechanisms associated to cellular proliferation and immune responses.
Assuntos
Biocombustíveis/toxicidade , Biocombustíveis/análise , Brasil , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Citocinas/metabolismo , Humanos , Espectrometria de Massas/métodos , Metais/análise , Metais/toxicidade , Hidrocarbonetos Policíclicos Aromáticos/análise , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Glycine maxRESUMO
Indoor smoke exposure may affect cardiovascular disease (CVD) risk via lung-mediated inflammation, oxidative stress, and endothelial inflammation. We sought to explore the association between indoor smoke exposure from burning biomass fuels and a selected group of markers for endothelial inflammation. We compared serum concentrations of amyloid A protein, E-selectin, soluble intercellular adhesion molecule 1 (ICAM-1) and VCAM-1, von Willebrand factor (vWF), and high-sensitivity C-reactive protein (hs-CRP) in 228 biomass-exposed vs. 228 non-exposed participants living in Puno, Peru. Average age was 56 years (s.d. = 13), average BMI was 26.5 kg/m(2) (s.d. = 4.4), 48% were male, 59.4% completed high school, and 2% reported a physician diagnosis of CVD. In unadjusted analysis, serum levels of soluble ICAM-1 (330 vs. 302 ng/ml; P < 0.001), soluble VCAM-1 (403 vs. 362 ng/ml; P < 0.001), and E-selectin (54.2 vs. 52.7 ng/ml; P = 0.05) were increased in biomass-exposed vs. non-exposed participants, respectively, whereas serum levels of vWF (1148 vs. 1311 mU/ml; P < 0.001) and hs-CRP (2.56 vs. 3.12 mg/l; P < 0.001) were decreased, respectively. In adjusted analyses, chronic exposure to biomass fuels remained positively associated with serum levels of soluble ICAM-1 (P = 0.03) and VCAM-1 (P = 0.05) and E-selectin (P = 0.05), and remained negatively associated with serum levels of vWF (P = 0.02) and hs-CRP (P < 0.001). Daily exposure to biomass fuel smoke was associated with important differences in specific biomarkers of endothelial inflammation and may help explain accelerated atherosclerosis among those who are chronically exposed.
Assuntos
Poluição do Ar em Ambientes Fechados/efeitos adversos , Biocombustíveis/toxicidade , Exposição Ambiental/efeitos adversos , Fumaça/efeitos adversos , Biomarcadores/sangue , Biomassa , Proteína C-Reativa/análise , Doenças Cardiovasculares/etiologia , Estudos de Casos e Controles , Selectina E/sangue , Feminino , Humanos , Inflamação/sangue , Inflamação/etiologia , Molécula 1 de Adesão Intercelular/sangue , Masculino , Pessoa de Meia-Idade , Peru , Fatores de Risco , Proteína Amiloide A Sérica/análise , Molécula 1 de Adesão de Célula Vascular/sangue , Fator de von Willebrand/análiseRESUMO
This study estimated end compared the potential toxic effects of the water-soluble fractions (WSF) of biodiesel (B100), diesel and the commercial biodiesel (B5) on Oreochromis niloticus. After a 24 h-exposition to WSF-0% (control) and WSF-serial concentrations of 4.6%, 10%, 22%, 46% and 100%, samples of gill and liver of the exposed fishes were fixed in Bouin's solution, processed, stained using hematoxylin/eosin and analyzed by light-microscopy. WSF-hydrocarbons and methanol contents, analyzed by gas chromatography, were checked against the occurrence of abnormal histopathological alterations. These were not found in the control and WSF-4.6% exposed fishes, while exposures to or above 10%-WSF resulted in histopathological alterations whose severity increased in a dose-dependent manner, being higher in fishes exposed to WSF-diesel, or WSF-B5 when compared to biodiesel. These results, which were corroborated by the chemical analyses, highlighted the histological technique as an appropriate diagnostic tool that can be used for the preservation of water bodies' quality.
Assuntos
Biocombustíveis/toxicidade , Ciclídeos/crescimento & desenvolvimento , Gasolina/toxicidade , Brânquias/efeitos dos fármacos , Fígado/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Animais , Biocombustíveis/análise , Brasil , Cromatografia Gasosa , Ciclídeos/metabolismo , Relação Dose-Resposta a Droga , Monitoramento Ambiental , Gasolina/análise , Brânquias/metabolismo , Brânquias/patologia , Fígado/metabolismo , Fígado/patologia , Solubilidade , Poluentes Químicos da Água/análiseRESUMO
Occupational toxicology and clinical pharmacology integration will be useful to understand potential exposure-drug interaction and to shape risk assessment strategies in order to improve occupational health. The aim of the present study was to evaluate the effect of exposure to ethanol fuel on in vivo activities of cytochrome P450 (CYP) isoenzymes CYP3A, CYP2C and CYP2D by the oral administration of the probe drugs verapamil, ibuprofen and fluoxetine. Male Wistar rats exposed to filtered air or to 2000 ppm ethanol in a nose-only inhalation chamber during (6 h/day, 5 days/week, 6 weeks) received single oral doses of 10 mg/kg verapamil or 25 mg/kg ibuprofen or 10 mg/kg fluoxetine. The enantiomers of verapamil, norverapamil, ibuprofen and fluoxetine in plasma were analyzed by LC-MS/MS. The area under the curve plasma concentration versus time extrapolated to infinity (AUC(0-∞)) was calculated using the Gauss-Laguerre quadrature. Inhalation exposure to ethanol reduces the AUC of both verapamil (approximately 2.7 fold) and norverapamil enantiomers (>2.5 fold), reduces the AUC(0-∞) of (+)-(S)-IBU (approximately 2 fold) and inhibits preferentially the metabolism of (-)-(R)-FLU. In conclusion, inhalation exposure of ethanol at a concentration of 2 TLV-STEL (6 h/day for 6 weeks) induces CYP3A and CYP2C but inhibits CYP2D in rats.
Assuntos
Biocombustíveis/toxicidade , Indutores das Enzimas do Citocromo P-450/toxicidade , Inibidores das Enzimas do Citocromo P-450/toxicidade , Sistema Enzimático do Citocromo P-450/metabolismo , Etanol/toxicidade , Exposição por Inalação/efeitos adversos , Testes de Toxicidade Crônica/métodos , Poluentes Ocupacionais do Ar/toxicidade , Animais , Hidrocarboneto de Aril Hidroxilases/antagonistas & inibidores , Hidrocarboneto de Aril Hidroxilases/metabolismo , Câmaras de Exposição Atmosférica , Biomarcadores/sangue , Biotransformação/efeitos dos fármacos , Citocromo P-450 CYP3A/química , Citocromo P-450 CYP3A/metabolismo , Inibidores das Enzimas do Citocromo P-450/sangue , Inibidores das Enzimas do Citocromo P-450/farmacocinética , Sistema Enzimático do Citocromo P-450/química , Indução Enzimática/efeitos dos fármacos , Fluoxetina/sangue , Fluoxetina/farmacocinética , Ibuprofeno/sangue , Ibuprofeno/farmacocinética , Limoneno Hidroxilases/antagonistas & inibidores , Limoneno Hidroxilases/metabolismo , Masculino , Ratos Wistar , Verapamil/análogos & derivados , Verapamil/sangue , Verapamil/química , Verapamil/farmacocinéticaRESUMO
The kinetics of gas production and in vitro ruminal degradation of diets contained replacement of soybean meal (SBM) by detoxicated castorbean meal (DCBM) (0, 15, 30 and 45% of substitution) were evaluated in this study. Values of gas production of non-fibrous carbohydrates (Vf1), fibrous carbohydrates (Vf2) and total carbohydrates (V) showed quadratic behavior, and by observation of equations can be obtained inclusions of 25% the V and Vf1 obtained maximum values of 174.7 and 237.8 ml gas / g DM, respectively. The potential degradability (PD) and effective degradability (ED) of dry matter showed quadratic behavior and by observation of equations can be perceive that up to 18.0% there was an increase in the values of PD and ED that obtained maximum values of 93.7% and 55.7%, respectively. The replacement of SBM by DCBM from 15 to 30% increased the kinetics of gas production and rumen degradation.(AU)
Assuntos
Animais , Ricinus , Rúmen , Inativação Metabólica , Biocombustíveis/toxicidade , Microbiota , Ruminantes/metabolismo , CinéticaRESUMO
The kinetics of gas production and in vitro ruminal degradation of diets contained replacement of soybean meal (SBM) by detoxicated castorbean meal (DCBM) (0, 15, 30 and 45% of substitution) were evaluated in this study. Values of gas production of non-fibrous carbohydrates (Vf1), fibrous carbohydrates (Vf2) and total carbohydrates (V) showed quadratic behavior, and by observation of equations can be obtained inclusions of 25% the V and Vf1 obtained maximum values of 174.7 and 237.8 ml gas / g DM, respectively. The potential degradability (PD) and effective degradability (ED) of dry matter showed quadratic behavior and by observation of equations can be perceive that up to 18.0% there was an increase in the values of PD and ED that obtained maximum values of 93.7% and 55.7%, respectively. The replacement of SBM by DCBM from 15 to 30% increased the kinetics of gas production and rumen degradation.(AU)
Assuntos
Animais , Ricinus , Rúmen , Inativação Metabólica , Biocombustíveis/toxicidade , Microbiota , Ruminantes/metabolismo , CinéticaRESUMO
Despite being considered friendlier to the environment, biodiesel fuel can be harmful to aquatic organisms, especially when combined with petroleum diesel fuel. In this work we evaluated the effects of mineral diesel fuel containing increasing concentrations of biodiesel (5% and 20%, namely B5 and B20) and pure biodiesel (B100), at concentrations of 0.001 and 0.01mLL(-1), after 15 days of exposure, in armored catfish (Pterygoplichtys anisitsi). Toxicity tests were also performed to estimate LC50 values (96h) for each compound. Biotransformation enzymes [ethoxyresorufin-O-deethylase (EROD), and glutathione S-transferase (GST)] as well as oxidative stress markers (superoxide dismutase, SOD, catalase, CAT, glutathione peroxidase, GPx, and the level of lipid peroxidation) were measured in liver and gills after treatment. Genotoxic effects were also accessed in erythrocytes using the comet assay and by evaluating the frequency of micronuclei formation. Further, the mRNA of cytochrome P450 1A (CYP1A) was also measured in liver. Mortality was not observed even exposure to concentrations as high as 6.0mLL(-1). EROD and GST activities were increased after B5 and B20 treatments; however, CYP1A mRNA induction was not observed. SOD and CAT activities were decreased, but GPx was significantly higher for all treatments in gills. There were no significant changes in lipid peroxidation, but genotoxicity markers revealed that all treatments increased comet scores. Fuels B5 and B20 increased micronuclei frequency. Our results indicate that despite being less toxic, biodiesel may cause sublethal alterations in fish that may alter long term health.
Assuntos
Biocombustíveis/toxicidade , Peixes-Gato/metabolismo , Sistema Enzimático do Citocromo P-450/metabolismo , Dano ao DNA , Animais , Catalase/metabolismo , Peixes-Gato/anatomia & histologia , Citocromo P-450 CYP1A1/metabolismo , Sistema Enzimático do Citocromo P-450/genética , Feminino , Gasolina/toxicidade , Brânquias/efeitos dos fármacos , Brânquias/enzimologia , Glutationa Peroxidase/metabolismo , Glutationa Transferase/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/enzimologia , Masculino , Estresse Oxidativo/efeitos dos fármacos , Superóxido Dismutase/metabolismoRESUMO
Transesterification has proved to be the best option for obtaining biodiesel and, depending on the type of alcohol used in the reaction, the type of biodiesel may be methyl ester or ethyl ester. Leaking biodiesel can reach water bodies, contaminating aquatic organisms, particularly fish. The objective of this study was to determine whether the soluble fraction of biodiesel (Bd), produced by both the ethylic (BdEt) and methylic (BdMt) routes, can cause cytotoxic, biochemical and genotoxic alterations in the hepatocyte cell line of Danio rerio (ZFL). The metabolic activity of the cell was quantified by the MTT reduction method, while genotoxic damage was analyzed by the comet assay with the addition of specific endonucleases. The production of reactive oxygen species (ROS) and antioxidant/biotransformation enzymes activity also were determined. The results indicate that both Bd increased ROS production, glutathione S-transferase activity and the occurrence of DNA damage. BdMt showed higher cytotoxicity than BdEt, and also caused oxidative damage to the DNA. In general, both Bd appear to be stressors for the cells, causing cytotoxic, biochemical and genetic alterations in ZFL cells, but the type and intensity of the changes found appear to be dependent on the biodiesel production route.
Assuntos
Biocombustíveis/toxicidade , Hepatócitos/efeitos dos fármacos , Mutagênicos/toxicidade , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Ensaio Cometa , Dano ao DNA , Glutationa Transferase/metabolismo , Hepatócitos/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Peixe-ZebraRESUMO
Biodiesel fuel is gradually replacing petroleum-based diesel oil use. Despite the biodiesel being considered friendlier to the environment, little is known about its effects in aquatic organisms. In this work we evaluated whether biodiesel exposure can affect oxidative stress parameters and biotransformation enzymes in armored catfish (Pterygoplichthys anisitsi, Loricariidae), a South American endemic species. Thus, fish were exposed for 2 and 7d to 0.01mLL(-1) and 0.1mLL(-1) of pure diesel, pure biodiesel (B100) and blends of diesel with 5% (B5) and 20% (B20) biodiesel. Lipid peroxidation (malondialdehyde) levels and the activities of the enzymes glutathione S-transferase, superoxide dismutase, catalase and glutathione peroxidase were measured in liver and gills. Also, DNA damage (8-oxo-7, 8-dihydro-2'-deoxyguanosine) levels in gills and 7-ethoxyresorufin-O-deethylase activity in liver were assessed. Pure diesel, B5 and B20 blends changed most of the enzymes tested and in some cases, B5 and B20 induced a higher enzyme activity than pure diesel. Antioxidant system activation in P. anisitsi was effective to counteract reactive oxygen species effects, since DNA damage and lipid peroxidation levels were maintained at basal levels after all treatments. However, fish gills exposed to B20 and B100 presented increased lipid peroxidation. Despite biodiesel being more biodegradable fuel that emits less greenhouse gases, the increased lipid peroxidation showed that biofuel and its blends also represent hazards to aquatic biota.
Assuntos
Biocombustíveis/toxicidade , Peixes-Gato/metabolismo , Poluentes Ambientais/toxicidade , Petróleo/toxicidade , Animais , Biomarcadores/metabolismo , Relação Dose-Resposta a Droga , Feminino , Brânquias/efeitos dos fármacos , Brânquias/enzimologia , Brânquias/metabolismo , Guanosina/análogos & derivados , Guanosina/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/enzimologia , Fígado/metabolismo , Masculino , Malondialdeído/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Fatores de TempoRESUMO
Biodiesel is promoted as environmentally less harmful than diesel fuel. Nevertheless its water-soluble-fraction (WSF) may contain methanol, which appears by a reversion of the transesterification reaction, when biodiesel contacts water. This paper evaluated the loss of the lysosomal membrane integrity in liver homogenate of juvenils Tilapia exposed to biodiesels-WSF, through the increase of the acid phosphatase activity, as an evidence of citotoxicity. Differences in the enzyme activity levels (3.4, 2.3 and 0.8 mU mg(-1) total protein over the control value, which was 1.6 mU mg(-1) total protein), found for castor oil, waste cooking-oil and palm oil-biodiesels, respectively, were indicative of their toxicity according to this decreasing trend. WSF-chromatograms suggest the cytotoxicity as related to methanol.
Assuntos
Fosfatase Ácida/análise , Biocombustíveis/toxicidade , Ciclídeos/metabolismo , Monitoramento Ambiental/métodos , Lisossomos/metabolismo , Fosfatase Ácida/metabolismo , Animais , Óleo de Rícino/metabolismo , Cromatografia Gasosa , Esterificação , Fígado/efeitos dos fármacos , Fígado/enzimologia , Metanol/metabolismo , Óleo de Palmeira , Óleos de Plantas/metabolismo , Medição de RiscoRESUMO
The water-soluble-fractions (WSF) from biodiesel and biodiesel/diesel blends were compared to diesel in their sub-lethal toxicity to microalgae. Chemical analyses of aromatics, non-aromatics hydrocarbons and methanol were carried out in the WSF, the former showing positive correlation with increasing diesel concentrations (B100 < B5 < B3 < B2 < D). Biodiesel interacted with the aqueous matrix, generating methanol, which showed lower toxicity than the diesel contaminants in blends. The WSF caused 50% culture growth inhibition (IC50-96 h) at concentrations varying from 2.3 to 85.6%, depending on the tested fuels and species. However, the same species sensitivity trend (S. costatum > N. oculata > T. chuii > P. subcapitata) was observed for all the tested fuels.
Assuntos
Biocombustíveis/toxicidade , Gasolina/toxicidade , Microalgas/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Relação Dose-Resposta a Droga , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Medição de RiscoRESUMO
The designation of biodiesel as an environmental-friendly alternative to diesel oil has improved its commercialization and use. However, most biodiesel environmental safety studies refer to air pollution and so far there have been very few literature data about its impacts upon other biotic systems, e.g. water, and exposed organisms. Spill simulations in water were carried out with neat diesel and biodiesel and their blends aiming at assessing their genotoxic potentials should there be contaminations of water systems. The water soluble fractions (WSF) from the spill simulations were submitted to solid phase extraction with C-18 cartridge and the extracts obtained were evaluated carrying out genotoxic and mutagenic bioassays [the Salmonella assay and the in vitro MicroFlow® kit (Litron) assay]. Mutagenic and genotoxic effects were observed, respectively, in the Salmonella/microsome preincubation assay and the in vitro MN test carried out with the biodiesel WSF. This interesting result may be related to the presence of pollutants in biodiesel derived from the raw material source used in its production chain. The data showed that care while using biodiesel should be taken to avoid harmful effects on living organisms in cases of water pollution.
Assuntos
Biocombustíveis/toxicidade , Gasolina/toxicidade , Mutagênicos/toxicidade , Poluentes Químicos da Água/toxicidade , Biocombustíveis/análise , Bioensaio , Monitoramento Ambiental/métodos , Gasolina/análise , Testes de Mutagenicidade , Mutagênicos/análise , Mutagênicos/química , Poluição por Petróleo/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Salmonella/efeitos dos fármacos , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/químicaRESUMO
The designation of biodiesel as a green fuel has increased its commercialization and use, making its fate in the environment a matter of concern. Fuel spills constitute a major source of aquatic pollution and, like diesel spills, biodiesel can produce adverse effects on aquatic environments, animals and humans. The present study assessed cytotoxic effects of water systems contaminated with neat biodiesel and its diesel blends by means of different procedures on human T cell leukemia (Jurkat) and human hepatocellular carcinoma (HepG2) cells [detection of changes in mitochondrial membrane potential (ΔΨ(m)) using tetramethylrhodamine ethyl ester (TMRE), apoptosis recognition by Annexin V and impedance real-time cell analyzer (xCELLigence™ system)]. The data obtained showed concordance across the different bioassays, with cytotoxic effects observed as a dose-dependent response only for waters contaminated with pure diesel (D100) and B5 blend, which is characterized by a mixture of 95% diesel and 5% biodiesel. The data can also lead us to hypothesize that diesel accounts for the harmful effects observed, and that biodiesel does not worsen the impacts caused by diesel pollution.
Assuntos
Biocombustíveis/toxicidade , Citotoxinas/toxicidade , Gasolina/toxicidade , Poluentes Químicos da Água/toxicidade , Linhagem Celular , Citotoxinas/química , Poluição Ambiental , Humanos , Solubilidade , Poluentes Químicos da Água/químicaRESUMO
Fossil fuels such as diesel are being gradually replaced by biodiesel, a renewable energy source, cheaper and less polluting. However, little is known about the toxic effects of this new energy source on aquatic organisms. Thus, we evaluated biochemical biomarkers related to oxidative stress in Nile tilapia (Oreochromis niloticus) after two and seven exposure days to diesel and pure biodiesel (B100) and blends B5 and B20 at concentrations of 0.01 and 0.1 mL L(-1). The hepatic ethoxyresorufin-O-deethylase activity was highly induced in all groups, except for those animals exposed to B100. There was an increase in lipid peroxidation in liver and gills in the group exposed to the higher concentration of B5. All treatments caused a significant increase in the levels of 1-hydroxypyrene excreted in the bile after 2 and 7d, except for those fish exposed to B100. The hepatic glutathione-S-transferase increased after 7d in animals exposed to the higher concentration of diesel and in the gill of fish exposed to the higher concentration of pure diesel and B5, but decreased for the two tested concentrations of B100. Superoxide dismutase, catalase and glutathione peroxidase also presented significant changes according to the treatments for all groups, including B100. Biodiesel B20 in the conditions tested had fewer adverse effects than diesel and B5 for the Nile tilapia, and can be suggested as a less harmful fuel in substitution to diesel. However, even B100 could activate biochemical responses in fish, at the experimental conditions tested, indicating that this fuel can also represent a risk to the aquatic biota.
Assuntos
Biocombustíveis/toxicidade , Gasolina/toxicidade , Estresse Oxidativo , Tilápia/metabolismo , Animais , Catalase/metabolismo , Citocromo P-450 CYP1A1/metabolismo , Brânquias/metabolismo , Glutationa Transferase/metabolismo , Peroxidação de Lipídeos , Superóxido Dismutase/metabolismo , Poluentes Químicos da Água/toxicidadeRESUMO
Concerns over the sustained availability of fossil fuels and their impact on global warming and pollution have led to the search for fuels from renewable sources to address worldwide rising energy demands. Biodiesel is emerging as one of the possible solutions for the transport sector. It shows comparable engine performance to that of conventional diesel fuel, while reducing greenhouse gas emissions. However, the toxicity of products and effluents from the biodiesel industry has not yet been sufficiently investigated. Brazil has a very high potential as a biodiesel producer, in view of its climatic conditions and vast areas for cropland, with consequent environmental risks because of possible accidental biodiesel spillages into water bodies and runoff to coastal areas. This research determined the toxicity to two marine organisms of the water-soluble fractions (WSF) of three different biodiesel fuels obtained by methanol transesterification of castor oil (CO), palm oil (PO), and waste cooking oil (WCO). Microalgae and sea urchins were used as the test organisms, respectively, for culture-growth-inhibition and early-life-stage-toxicity tests. The toxicity levels of the analyzed biodiesel WSF showed the highest toxicity for the CO, followed by WCO and the PO. Methanol was the most prominent contaminant; concentrations increased over time in WSF samples stored up to 120 d.