Acute and subchronic effects of petroleum on the freshwater fish Hoplias aff. malabaricus / Efeitos agudo e subcrônico do petróleo no peixe de água doce Hoplias aff. malabaricus

Abstract Petroleum water soluble fraction (WSF) impairs organisms, but damages may vary among cell and tissue levels. The aim of the present study was to evaluate the acute (24 h, 48 h, 72 h) and subchronic effects (36 days) of WSF (0%, 25% and 100%) in juveniles of the Neotropical top predator fish Hoplias aff. malabaricus. The effects of WSF were evaluated at a molecular level using the comet assay and micronucleus test for genome damage; and at a morphological level through histological identification of liver pathologic lesions. In both acute and subchronic exposure we found low levels of DNA damage (< 10% of comet tail) and non-significant frequency of micronucleus in WSF exposed fish. The most significant liver lesions in WSF exposed fish were fatty vacuolization, hypertrophy and focal necrosis. Since these tissue injuries were progressive and persistent, their irreversibility may negatively affect fish recruitment, even in a such resistant top predator.

Resumo A fração solúvel de petróleo (WSF) prejudica os organismos, porém os danos podem variar entre os níveis celular e tecidual. O objetivo do presente estudo foi avaliar o efeito agudo (24 h, 48 h e 72 h) e subcrônico (36 dias) da WSF (0%, 25% e 100%) em juvenis do peixe neotropical predador topo Hoplias aff. malabaricus. Os efeitos da WSF foram avaliados no nível molecular utilizando o ensaio do cometa e o teste do micronúcleo para o dano genômico e no nível morfológico através da identificação histológica de lesões patológicas no fígado. Em ambas exposições (aguda e subcrônica) encontramos baixos níveis de dano no DNA (< 10% de DNA na cauda do cometa) e frequência de micronúcleos não significativa em peixes expostos a WSF. As lesões mais significativas no fígado dos peixes expostos a WSF foram a vacuolização lipídica, hipertrofia e focos de necroses. Como estas lesões foram progressivas e persistentes, sua irreversibilidade pode afetar negativamente o recrutamento dos peixes, mesmo sendo um predador topo resistente.

Biodegradation of petroleum by bacteria isolated from fishes of Indian Ocean / Biodegradação do petróleo por bactérias isoladas de peixes do oceano Índico

In this study, oil degrading bacteria discovered from fish living near the oil ports at Karachi in Pakistan were characterized. The bacteria isolated from skin, gills, and gut in fish could consume crude oil as a source of carbon and energy. Total 36 isolates were tested using Nutrient Agar (NA) and MSA media with different crude oil concentrations (0.2%, 0.5%, 0.7%, 1%, 2%, and 5%) and 4 out of 36 isolates (two Gram positive and two Gram negative bacteria) were selected for further identification. 16S rRNA gene sequencing revealed that the isolates are related to Bacillus velezensis, Bacillus flexus, Pseudomonas brenneri and Pseudomonas azotoforman. Oil degrading potential of these bacteria was characterized by GC-MS analysis of degradation of oil components in crude oil as well as engine oil. We found that one (2, 6, 10, 14-Tetramethylpentadecane) out of 42 components in the crude oil was fully eliminated and the other oil components were reduced. In addition, 26 out of 42 oil components in the engine oil, were fully eliminated and the rest were amended. Taken together, these studies identify that B. velezensis, B. flexus, P. brenneri and P. azotoforman have high oil degrading potential, which may be useful for degradation of oil pollutants and other commercial applications.

Neste estudo, bactérias degradadoras de óleo descobertas em peixes que vivem perto dos portos de petróleo em Karachi, no Paquistão, foram caracterizadas. As bactérias isoladas da pele, guelras e intestinos dos peixes podem consumir petróleo bruto como fonte de carbono e energia. No total, 36 isolados foram testados usando Agar Nutriente (NA) e meio MSA com diferentes concentrações de óleo bruto (0,2%, 0,5%, 0,7%, 1%, 2% e 5%) e 4 de 36 isolados (dois Gram positivos e duas bactérias Gram negativas) foram selecionadas para posterior identificação. O sequenciamento do gene 16S rRNA revelou que os isolados estão relacionados a Bacillus velezensis, Bacillus flexus, Pseudomonas brenneri e Pseudomonas azotoforman. O potencial de degradação do óleo dessas bactérias foi caracterizado pela análise de GC-MS da degradação dos componentes do óleo no óleo cru, bem como no óleo do motor. Descobrimos que um (2, 6, 10, 14-tetrametilpentadecano) de 42 componentes do óleo cru foi totalmente eliminado e os outros componentes do óleo foram reduzidos. Além disso, 26 dos 42 componentes do óleo do motor foram totalmente eliminados e o restante corrigido. Juntos, esses estudos identificam que B. velezensis, B. flexus, P. brenneri e P. azotoforman têm alto potencial de degradação de óleo, o que pode ser útil para a degradação de poluentes de óleo e outras aplicações comerciais.

Isolation and characterization of hydrocarbon-degrading bacteria from gas station leaking-contaminated groundwater in the Southern Amazon, Brazil / Isolamento e caracterização de bactérias degradadoras de hidrocarbonetos de água subterrânea contaminada por vazamentos em posto de combustível no sul da Amazônia, Brasil

Abstract Twenty-three hydrocarbon-degrading bacteria strains were isolated from gas station leaking-contaminated groundwater located in the Southern Amazon, Brazil. Based on hydrocarbon (diesel, hexadecane, benzene, toluene and xylene) degradation ability, two strains were selected for further study. The amplification and sequencing of the 16S rRNA gene showed that these two strains belonged to the genus Bacillus (Bacillus sp. L26 and Bacillus sp. L30). GC-MS analysis showed that strain L30 was the most effective in degrading n-alkane (C10-C27) from diesel after 7 days of cultivation in mineral medium. Both strains produced biosurfactants and showed emulsification activity, specially the strain L30. Alkane hydroxylase gene (group III), which is important for alkane biodegradation, was present in strains. As a result, this study indicated that these bacteria could have promising applications in hydrocarbon bioremediation.

Resumo Vinte e três linhagens bacterianas degradadoras de hidrocarbonetos foram isoladas de água subterrânea contaminada por vazamento em posto de combustível no sul da Amazônia, Brasil. Com base na habilidade de degradar hidrocarbonetos (diesel, hexadecano, benzeno, tolueno e xileno), duas linhagens foram selecionadas para estudos posteriores. A amplificação e sequenciamento do gene 16S rRNA demonstrou que essas linhagens pertencem ao gênero Bacillus (Bacillus sp. L26 and Bacillus sp. L30). Análises de GC-MS mostraram que a linhagem L30 foi mais eficiente em degradar n-alcanos (C10-C27) presentes no diesel, após 7 dias de cultivo em meio mineral. Ambas as linhagens produziram biossurfactantes e apresentaram atividade emulsificante, especialmente a linhagem L30. O gene alcano hidroxilase (grupo III), o qual é importante para degradação de alcanos, foram detectados nas linhagens. Como resultado, este estudo indicou que essas linhagens bacterianas podem ser promissoras se aplicadas em processos de biorremediação.

Aspectos de regulação internacional do petróleo: o caso Brasil / Aspects of international oil regulation: the Brazil case

O presente trabalho tem por objeto abordar os aspectos de regulação internacional do petróleo, mais precisamente aqueles previstos na Convenção das Nações Unidas sobre o direito do mar de 1982, que definem a obrigatoriedade do pagamento de royalties às Nações Unidas advindos da exploração dos hidrocarbonetos nas plataformas estendidas. Utiliza o método dedutivo e o tipo de pesquisa exploratório e comparativo, o artigo dividiu-se em três capítulos. Após introduzir o leitor ao tema, abordando-se as particularidades do direito do mar e seu viés de exploração econômica, os autores discorrem sobre a questão com uma dimensão da regulação quase sempre ausente da formulação de políticas energéticas. Essa discussão é apresentada a partir do estudo de caso do Brasil. Para tanto, cuida de apresentar a importância do setor petrolífero e o histórico da exploração offshore no Brasil. Adentra-se em seguida a temática da distribuição dos royalties entre o estado nacional e as nações unidas. No desenvolvimento da questão são trazidos à tona o possíveis cenários entre o futuro da exploração petrolífera no Brasil e os resultados da aplicação da regulação internacional pela Convenção das Nações Unidas sobre o Direito do Mar de 1982. Por fim, chegou-se à conclusão de que algumas plataformas de petróleo já estão localizadas próximas do limite das 200 milhas marítimas e o polígono do pré-sal também encontra-se adentrando as 200 milhas marítimas, o que demonstra uma necessidade de uma abordagem imparcial sobre os prós e contras do posicionamento brasileiro, analisando os possíveis cenários futuros.

This papers seeks to verify aspects of the international regulation of oil, specifically those contained in the 1982 United Nations Convention on the Law of the Sea that refer to the obligation to pay royalties to the United Nations on the exploration by the Brazilian government of hydrocarbons in extended platforms. The deductive method and exploratory and comparative research were used. After identifying how the work was carried out, it discusses the issue of law of the sea and the economic exploitation discourses on the theme, their motivation and the context of work to be investigated. The authors also discuss the issue within the dimension of regulation being almost always absent from the formulation of energy policies. The discussion is grounded on a case study of Brazil and presents the importance of the oil industry, the history of offshore exploration in Brazil, and even the distribution of royalties between the national state and the United Nations. In the development of this issue, possible scenarios are brought to light regarding the future of offshore oil exploration in Brazil and the results of enforcement of international regulation by the 1982 United Nations Convention on the Law of the Sea. Finally, we reach the conclusion that some oil rigs are already located near the 200 nautical miles limit and that the polygon of the pre-salt oils reserves is also entering this limit, demonstrating the need for an impartial reckoning of the pros and cons of Brazil's position by analyzing possible future scenarios.

Evaluación in vitro de la capacidad biorremediadora de hongos filamentosos sobre petróleo crudo / Bioremediative Capacity Evaluation in vitro of the filamentous fungi on crude oil

Resumen Objetivo. Evaluar la capacidad biorremediadora de algunas especies de hongos filamentosos en suelos contaminados con petróleo crudo. Métodos. Se aislaron 138 cepas a partir de 90 cultivos primarios en muestras de suelos obtenidas en los municipios de Yondó (Antioquia), Acacías (Meta) y Tumaco (Nariño), se identificaron las especies por medio de claves taxonómicas y la amplificación por PCR de la región ITS ubicándose en siete géneros de hongos filamentosos. Del total de las especies se escogieron tres para el experimento que fueron: Neosartorya sp. Cepa A/N -1, Aspergillus sp. Cepa Y/As-3 y Rhizomucor sp. Cepa 1A/R-1; se realizó la micorremediación con la técnica de Landfarming modificado al diseñarse un microcosmos con 50g de suelo contaminado con petróleo crudo °API de 21.6 a concentraciones de 20.000 ppm y 30.000ppm para cada una de las especies en un inóculo de 300 conidios/ml en agua destilada, ajustado en cámara de Neubauer y las tres especies en consorcio en suelo contaminado con petróleo crudo °API de 21.6 a concentraciones de 40.000ppm, 60.000ppm, 80.000ppm y 100.000ppm con un inóculo de 300 conidios/ml. Se valoró el proceso por espectofotometría. Además se estableció las enzimas empleadas en la micorremediación y la citotoxicidad de las cepas empleadas. Resultado. La micorremediación realizada por las especies individuales fue en promedio entre 2 y 6 días y cuando se aplicaron las tres especies en consorcio se realizó en un promedio entre 6 y 10 días, la enzima empleada es peroxidasa y la citotoxicidad es negativa.

Abstract Objective. Evaluate the bioremediation capacity of some species of filamentous fungi in soils contaminated with crude oil. Methods. 138 strains were isolated from 90 primary culture in soil samples obtained in the municipalities of Yondó (Antioquia), Acacías (Meta) and Tumaco (Nariño), species were identified by means of taxonomic keys and PCR amplification of the ITS region located in seven genera of filamentous fungi. Of the total of the species, three were chosen for the experiment, which were: Neosartorya sp. Cepa A/N- 1, Aspergillus sp. Cepa Y/As -3 and Rhizomucor sp. Cepa 1A/R-1; Micoremediation was performed with the modified Landfarming technique when designing a microcosm with 50g of soil contaminated with crude oil API 21.6 at concentrations of 20,000 ppm and 30,000ppm for each of the species in an inoculum of 300 conidia / ml in water distilled, adjusted in Neubauer chamber and the three species in consortium in soil contaminated with crude oil API 21.6 at concentrations of 40,000ppm, 60,000ppm, 80,000ppm and 100,000ppm with an inoculum of 300 conidia / ml. The process was evaluated by spectrophotometry. In addition, the enzymes used in the micoremediation and cytotoxicity of the strains used were established. Result. The micoremediation performed by the individual species was on average between 2 and 6 days and when the three species were applied in a consortium it was carried out on average between 6 and 10 days, the enzyme used is peroxidase and the cytotoxicity is negative.

Indagación exploratoria in vitro de la capacidad degradadora de la cepa comercial Pleurotus ostreatus sobre dos concentraciones de petróleo crudo / In vitro inquiry on two concentrations of crude oil degradation ability by a commercial strain of Pleurotus ostreatus

Resumen Objetivo. Evaluar la potencial actividad degradadora de la cepa comercial Pleurotus ostreatus sobre petróleo crudo como única fuente de carbono. Método. Se empleó un inóculo de 10mg del hongo en medio mínimo líquido de sales con volúmenes de 0,5% y 1% de petróleo en agitación constante durante 21 días a temperatura ambiente, registrando peso seco a los 0, 8,15 y 21 días. Resultados. Se obtuvo un máximo de biomasa 45mg para 0,5% de 39mg para 1%. Esto sugiere que el hongo sufre una adaptación fisiológica para utilizar el petróleo crudo para su crecimiento.

Abstract Objectives. To evaluate the potential crude oil-degrading activity of Pleurotus ostreatus using it as the sole source of carbon and energy for growth. Methods. An inoculum of 10 mg of the fungus in the minimal liquid of salt with 0.5% or 1% crude oil in constant agitation for 21 days was used. Dry weight at 0, 8, 15 and 21 days was obtained. Results. The maximum biomass with a value of 45mg of 0.5% oil treatment registered while the 1% oil treatment reached a value of 39mg. These values suggest physiological adaptation of the fungus to crude oil as its sole carbon source for growth.

Petroleum contamination and bioaugmentation in bacterial rhizosphere communities from Avicennia schaueriana

ABSTRACT Anthropogenic activity, such as accidental oil spills, are typical sources of urban mangrove pollution that may affect mangrove bacterial communities as well as their mobile genetic elements. To evaluate remediation strategies, we followed over the time the effects of a petroleum hydrocarbon degrading consortium inoculated on mangrove tree Avicennia schaueriana against artificial petroleum contamination in a phytoremediation greenhouse experiment. Interestingly, despite plant protection due to the inoculation, denaturing gradient gel electrophoresis of the bacterial 16S rRNA gene fragments amplified from the total community DNA indicated that the different treatments did not significantly affect the bacterial community composition. However, while the bacterial community was rather stable, pronounced shifts were observed in the abundance of bacteria carrying plasmids. A PCR-Southern blot hybridization analysis indicated an increase in the abundance of IncP-9 catabolic plasmids. Denaturing gradient gel electrophoresis of naphthalene dioxygenase (ndo) genes amplified from cDNA (RNA) indicated the dominance of a specific ndo gene in the inoculated petroleum amendment treatment. The petroleum hydrocarbon degrading consortium characterization indicated the prevalence of bacteria assigned to Pseudomonas spp., Comamonas spp. and Ochrobactrum spp. IncP-9 plasmids were detected for the first time in Comamonas sp. and Ochrobactrum spp., which is a novelty of this study.

The effects of oil pollution in the development of Ejidal Communities: the case of the San Juan river basin (Nuevo León, Mexico) / Los efectos de la contaminación petrolera en el desarrollo de comunidades ejidales: el caso de la cuenca del río san juan (nuevo león, méxico)

RESUMEN La presente investigación analiza, en varios ejidos, los efectos sociales, económicos y ecológicos causados por el derrame de petróleo en el río San Juan (Nuevo León, México). Con este fin, se realizaron encuestas entre los pobladores y entrevistas a actores clave. Los resultados de la investigación indican que, sobre todo, la problemática social causada por el desastre es poco valorada y atendida por el perpetrador y descuidada por el Estado. Lo anterior muestra la inconciencia o la corrupción del Gobierno para internalizar los costos sociales que ocasiona la producción de un producto que en su momento fue monopolio del Estado y, por tanto, debía beneficiar al conjunto de la población.

ABSTRACT The present investigation analyzes, in several ejidos, the social, economic and ecological effects caused by the oil spill in the San Juan River (Nuevo León, Mexico). To this end, surveys were conducted among the settlers and interviews with key actors. The results of the investigation indicate that, above all, the social problems caused by the disaster are little valued and taken care of by the perpetrator and neglected by the State. The shows the unconsciousness or corruption of the Government to internalize the social costs caused by the production of a product that at the time was a monopoly of the State and, therefore, should benefit the entire population.

Reintroducing plant coverage in a tropical wetland contaminated with oil and sulfate: rhizosphere effects on Desulfovibrio populations / Reintroducción de cobertura vegetal en un humedal tropical contaminado con petróleo y sulfato: efecto de la rizosfera sobre poblaciones de Desulfovibrio

Abstract The Mexican tropical wetland is a coastal system with capacity to support the contamination derived from the extractive industry and the transformation of crude oil, due to its high plant biodiversity and the presence of rhizospheric reducing sulphate bacteria from plants tolerant to crude oil. A field experiment was carried out for nine months to evaluate the adaptation of aquatic plants Leersia hexandra grass and Eleocharis palustris spikerush reintroduced in a wetland contaminated with 75 560 to 118 789 mg kg-1 of weathered petroleum and also with sulfate, derived from oil and gas pipeline leaks, and gaseous emissions. The effect of the weathered oil and sulfate on the dry matter production and the population density of the bacterium Desulfovibrio spp, isolated from the rhizosphere and soil of both plants, were evaluated. The means of the variables had statistical differences (p< 0.05). Weathered oil inhibited dry matter production of L. hexandra but not E. palustris; the effect of petroleum on Desulfovibrio density was very significant negative in the rhizosphere and in the soil of both plants. Sulfate reduced the dry matter of grass. The exposure of Desulfovibrio to sulfate significantly reduced its density in rhizosphere and soil (p< 0.01). We recommend the use of E. palustris for the decontamination of flooded soils contaminated with weathered oil and sulfate. Rev. Biol. Trop. 66(2): 908-917. Epub 2018 June 01.

Resumen El humedal tropical mexicano es un sistema costero con capacidad para resistir la contaminación derivada de la industria extractiva y la transformación del petróleo crudo, debido a su alta biodiversidad de plantas y la presencia de bacterias rizosféricas reductoras de sulfato de plantas tolerantes al petróleo crudo. Se realizó un experimento en campo durante nueve meses para evaluar la adaptación de las plantas acuáticas Leersia hexandra y Eleocharis palustris reintroducidas en un humedal contaminado con 75 560 a 118 789 mg kg-1 de petróleo intemperizado y también con sulfato, derivados de fugas de oleoductos y de emisiones gaseosas crónicas. Se evaluó el efecto del petróleo intemperizado y del sulfato en la producción de materia seca vegetal y en la densidad poblacional de la bacteria Desulfovibrio spp, aislada de la rizosfera y del rizoplano de ambas especies vegetales. Las medias de las variables tuvieron diferencias estadísticas (p< 0.05). El petróleo intemperizado inhibió la producción de materia seca de L. hexandra pero no de E. palustris; el efecto del petróleo en la densidad de Desulfovibrio fue negativo muy significativo en la rizosfera y en el rizoplano de ambas plantas. El sulfato redujo la materia seca de L. hexandra. La exposición de Desulfovibrio a sulfato redujo muy significativamente (p< 0.01) su densidad en rizosfera y en rizoplano. Recomendamos el uso de E. palustris para la descontaminación de suelos inundables afectados con petróleo intemperizado y con sulfato.

Temporal assessment of microbial communities in soils of two contrasting mangroves

ABSTRACT Variations in microbial communities promoted by alterations in environmental conditions are reflected in similarities/differences both at taxonomic and functional levels. Here we used a natural gradient within mangroves from seashore to upland, to contrast the natural variability in bacteria, cyanobacteria and diazotroph assemblages in a pristine area compared to an oil polluted area along a timespan of three years, based on ARISA (bacteria and cyanobacteria) and nifH T-RFLP (diazotrophs) fingerprinting. The data presented herein indicated that changes in all the communities evaluated were mainly driven by the temporal effect in the contaminated area, while local effects were dominant on the pristine mangrove. A positive correlation of community structure between diazotrophs and cyanobacteria was observed, suggesting the functional importance of this phylum as nitrogen fixers in mangroves soils. Different ecological patterns explained the microbial behavior in the pristine and polluted mangroves. Stochastic models in the pristine mangrove indicate that there is not a specific environmental factor that determines the bacterial distribution, while cyanobacteria and diazotrophs better fitted in deterministic model in the same area. For the contaminated mangrove site, deterministic models better represented the variations in the communities, suggesting that the presence of oil might change the microbial ecological structures over time. Mangroves represent a unique environment threatened by global change, and this study contributed to the knowledge of the microbial distribution in such areas and its response on persistent contamination historic events.

Characterization of dioxygenases and biosurfactants produced by crude oil degrading soil bacteria

ABSTRACT Role of microbes in bioremediation of oil spills has become inevitable owing to their eco friendly nature. This study focused on the isolation and characterization of bacterial strains with superior oil degrading potential from crude-oil contaminated soil. Three such bacterial strains were selected and subsequently identified by 16S rRNA gene sequence analysis as Corynebacterium aurimucosum, Acinetobacter baumannii and Microbacterium hydrocarbonoxydans respectively. The specific activity of catechol 1,2 dioxygenase (C12O) and catechol 2,3 dioxygenase (C23O) was determined in these three strains wherein the activity of C12O was more than that of C23O. Among the three strains, Microbacterium hydrocarbonoxydans exhibited superior crude oil degrading ability as evidenced by its superior growth rate in crude oil enriched medium and enhanced activity of dioxygenases. Also degradation of total petroleum hydrocarbon (TPH) in crude oil was higher with Microbacterium hydrocarbonoxydans. The three strains also produced biosurfactants of glycolipid nature as indicated d by biochemical, FTIR and GCMS analysis. These findings emphasize that such bacterial strains with superior oil degrading capacity may find their potential application in bioremediation of oil spills and conservation of marine and soil ecosystem.

Modelación de riesgos hacia los trabajadores y comunidad por emisiones de gas licuado de petróleo, utilizando software Slab View en la ciudad de Los Ángeles, Chile / Risks modeling to workers and the community for releases of petroleum liquid gas, using software slab view in los angeles city, Chile

RESUMEN: 21. Con el software SLAB VIEW se realizaron modelaciones para determi nar cuantitativamente los riesgos hacia los trabajadores y comunidad por emisiones accidentales de gas licuado de petróleo, desde fuentes de uso y almacenamiento, dentro del radio urbano de Los Ángeles (Chile). Se modelaron 23 fuentes con categoría de riesgo grave, clase "C" y las 3 fuentes con categoría muy grave, clase "D", identificadas con la meto dología APELL, aplicada en el estudio de Silva et. al (2016). 22. 23. Se evaluó el comportamiento espacial y temporal de las fugas de gas para estanques identificados con capacidades de 2 m3, 4 m3, 11 m3 y 49 m3 utilizando promedios estacionales de variables meteorológicas consideradas en un periodo de evaluación de cinco años. Se utiliza ron variables de tiempo de fuga evaluando su comportamiento en 1, 3 y 5 minutos, con el fin de identificar las condiciones del peor escenario. Como resultado se obtiene que el comportamiento de la nube depende de la estabilidad atmosférica, siendo la condición esta ble donde concentraciones de interés permanecen por más tiempo alcanzando mayores distancias y que el peor escenario para una fuga son las bajas temperaturas y las condiciones atmosféricas estables. Como conclusión, puede establecerse que en la zona de estudio exis ten estanques que son potencialmente peligrosos por deflagración para trabajadores y la comunidad; sin embargo, los tiempos de expo sición no generan peligros por exposición aguda.

ABSTRACT: 28. With the SLAB VIEW software, modeling wasperformed to determine quantitatively the risks to workers and the community from acciden tal releases of liquefied petroleum gas, from sources use and storage, within the urban radius of Los Angeles (Chile). 23 sources with a severe risk category class "C" and the 3 very severe risk category class "D" identified with the APELL methodology, applied in the study by Silva et al. (2016), were modeled. 29. 30. The spatial and temporal behavior of the gas leaking for tanks iden tified with capacities of 2m3, 4m3, 11m3 and 49m3 were evaluated using seasonal averages of meteorological variables considered in a five - year evaluation period. Leakage time variables were used evaluating their behavior in 1, 3 and 5 minutes in order to identify worst-case conditions. As a result it is obtained that the behavior of the cloud depends on the atmospheric stability, being the stable condition where concentrations of interest remain longer reaching greater distances and that the worst scenario for a leak is the low temperatures and the stable atmospheric conditions. As a conclusion, it can be established that in the study area, there are ponds that are potentially dangerous due to deflagration for workers and the com munity, however, exposure times do not generate hazards due to acute exposure.

Ideias e economia nas reformas das políticas públicas do setor de petróleo brasileiro: 1995 a 2010 / Ideas y economía en las reformas de las políticas públicas del sector de petróleo brasileño: 1995 a 2010 / Ideas and economy in the policy reforms of the Brazilian oil sector: 1995 to 2010

Resumo Este trabalho examina as mudanças no gerenciamento das receitas petrolíferas desde os anos 1990, período das reformas orientadas para o mercado, até o novo marco regulatório do petróleo aprovado em 2010. Baseado na combinação da perspectiva de longo prazo do institucionalismo histórico e nas ferramentas para modelar o comportamento dos agentes do institucionalismo da escolha racional, o estudo sublinha a importância das ideias e dos interesses no resultado da política pública, considerando a interação dos atores no processo, o marco institucional, novas conjunturas críticas e configurações nacionais e internacionais. Os resultados indicam que a política pública de petróleo no Brasil segue uma trajetória calcada nas ideias vigentes durante o período, refletindo os interesses dominantes em cada fase. Além disso, a situação econômica doméstica teve papel-chave ao determinar a necessidade de seguir as recomendações de políticas econômicas das organizações financeiras internacionais.

Resumen Este trabajo examina los cambios en la gestión de los ingresos petroleros desde el período de las reformas orientadas al mercado de los años 1990 hasta el nuevo marco regulatorio del petróleo aprobado en 2010. Basado en la combinación de la perspectiva a largo plazo del institucionalismo histórico y en las herramientas del institucionalismo de la elección racional para modelar el comportamiento de los agentes, el estudio subraya la importancia de las ideas e intereses en el resultado de la política pública, considerando la interacción de los actores en el proceso, el marco institucional, nuevas coyunturas críticas y configuraciones nacionales e internacionales. Los resultados indican que la política pública de petróleo en Brasil siguió la trayectoria de las ideas durante el período, reflejando los intereses dominantes en cada fase. Además, la situación económica doméstica desempeñó un papel clave al determinar la necesidad de seguir las recomendaciones de políticas económicas de las organizaciones financieras internacionales.

Abstract This paper examines changes in oil revenue management in the period from the market-oriented reforms of the 1990s to the new oil sector regulatory framework introduced in 2010. Grounded on a combination of the long-term view afforded by historical institutionalism and the tools for modelling agents' behaviour offered by rational choice institutionalism, it stresses the importance of ideas and associated interests in the policy outcome, considering stakeholder interaction in the process, the institutional framework, the new critical juncture, and the new domestic and international setting. The result indicates that the Brazilian oil policy follows the ideas path during the 1990s and 2000s, reflecting the dominant interests in each phase. As well, the domestic economic outlook was critical to determine the extent to which the government had to follow international agencies policy recommendations.

Draft genome analysis of Dietzia sp. 111N12-1, isolated from the South China Sea with bioremediation activity

Abstract Dietzia sp. 111N12-1, isolated from the seawater of South China Sea, shows strong petroleum hydrocarbons degradation activity. Here, we report the draft sequence of approximately 3.7-Mbp genome of this strain. To the best of our knowledge, this is the first genome sequence of Dietzia strain isolated from the sea. The genome sequence may provide fundamental molecular information on elucidating the metabolic pathway of hydrocarbons degradation in this strain.

Biosurfactants produced by Microbacterium sp, isolated from aquatic macrophytes in hydrocarbon-contaminated area in the Rio Negro, Manaus, Amazonas / Biossurfactantes produzidos por Microbacterium sp, isolada de macrófita aquática em área impactada por hidrocarbonetos no rio Negro, Manaus, Amazonas

Endophytic bacteria isolated from Eichhornia crassipes (Mart) Solms., collected in oil contaminated wastewater of effluent generated by Petrobras refinery in Manaus were investigated to determine their potential for producing biosurfactants. Assay with 2.6-dichlorophenol indophenol (DCPIP) indicator to verify hydrocarbon biodegradation activity; oil emulsification test; drop-collapse method; surface tension and growth curve of biosurfactant production. The M87 Microbacterium sp. strain chosen for this work was identified by the sequencing of the rDNA region and the chemical characterization was performed by FTIR, UFLC/MS and 1H RMN techniques. The selected bacterial isolate provided 3g L-1 of biosurfactant, using diesel oil as sole carbon source, being efficient in biodegrading oil as demonstrated by the DCPIP test. Fractions obtained by column chromatography were efficient in reducing water surface tension around 40 mN m-1, especially fraction 1, which reduced it to 34.17 mN m-1. The different techniques of chemical analysis used for the identification of the biosurfactant isolate indicated that this is probably a long - chain fatty acid lipid type, which may be used in the future as both biosurfactant in decontamination processes of hydrocarbon-polluted areas or as bioemulsifier in countless processes, since it exhibited no toxicity as determined by Alamar Blue assay.

Foram investigadas bactérias endofíticas isoladas de Eichhornia crassipes (Mart.) Solms., coletadas em águas contaminadas com resíduos de petróleo em um afluente da refinaria da Petrobrás/Manaus, para avaliação da produção de biossurfactantes. Para selecionar o micro-organismos à produção e caracterização de biossurfactantes, foram realizados os seguintes testes: a descoloração do indicador 2,6 indofenol (DCPIP), emulsificação do diesel, colapso da gota, tensão superficial e curva de produção. A caracterização química foi realizada por meio das técnicas de FT-IR, UFLC/MS e RMN1H. A bactéria M87 Microbacterium neste estudo, foi identificada pelo sequenciamento da região rDNA e produziu 3g L-1 de biossurfactantes utilizando o diesel como fonte de carbono, mostrando-se eficiente na ação biodegradadora do petróleo, por meio do teste de Indofenol (DCPIP). As frações obtidas, mostraram-se eficazes na redução da tensão superficial da água abaixo de 40 mN m-1, com destaque para a fração 1 que reduziu a tensão superficial para 34,17 mN m-1. Pelas análises química utilizadas, pode-se inferir que, provavelmente, se trata de um ácido graxo de cadeia longa, que pode ser utilizado futuramente tanto como biossurfactante em processos de descontaminação de ambientes impactados por hidrocarbonetos, assim como bioemulsificante em inúmeros processos uma vez que não apresentou toxicidade por meio do teste realizado.

Uso de Leersia hexandra (Poaceae) en la fitorremediación de suelos contaminados con petróleo fresco e intemperizado / Use of Leersia hexandra (Poaceae) for soil phytoremediation in soils contaminated with fresh and weathered oil

ResumenLa industria petrolera ha generado derrames crónicos de petróleo y su acumulación en Gleysoles en zonas anegadas en el estado de Tabasco, en el sureste de México. El anegamiento es un factor que limita el uso de tecnologías de remediación por el alto costo y los bajos niveles de degradación del petróleo, sin embargo, Leersia hexandra Sw. es un pasto que crece en estas zonas contaminadas con petróleo intemperizado. El objetivo del estudio fue evaluar la densidad de bacterias, producción de biomasa vegetal y fitorremediación de L.hexandra en suelo contaminado con petróleos fresco e intemperizado, bajo condiciones experimentales de anegamiento. Se realizaron dos experimentos (E1 y E2) en un túnel de plástico. El E1 se basó en ocho dosis: 6 000, 10 000, 30 000, 60 000, 90 000, 120 000, 150 000 y 180 000 mg kg-1 base seca (b.s.) de hidrocarburos totales de petróleo fresco (HTPF), y en el E2 se evaluaron cinco dosis: 14 173, 28 400, 50 598, 75 492 y 112 142 mg kg-1 b. s. de hidrocarburos totales de petróleo intemperizado (HTPI), con ocho repeticiones en cada experimento, además se utilizó un testigo con 2 607 mg kg-1 b. s. de HTP de origen biogénico. Las variables evaluadas a los tres y seis meses fueron 1) densidad microbiana de las bacterias fijadoras de nitrógeno de vida libre totales (BFN), del grupo Azospirillum (AZP) y Azotobacter (AZT), por cuenta viable en placa seriada; 2) producción de materia seca total (MS), se cuantificó por el peso seco por gravimetría, y 3) el porcentaje de descontaminación de los hidrocarburos (DSC) por extracción en equipo soxhlet. En suelos con HTPF, la población de BFN, AZP y AZT se estimuló hasta cinco veces más que el tratamiento testigo a los tres y seis meses; sin embargo, concentraciones de 150 000 y 180 000 mg kg-1 b. s. inhibieron entre un 70 y 89 % la densidad bacteriana. A su vez, en suelos con PI, la inhibición se registró hasta en un 90 %, a excepción del tratamiento con 14 173 mg kg-1 b. s., el cual estimuló las BNF y AZT en 2 y 0.10 veces más que testigo, respectivamente. La producción de MS fue continua en los experimentos hasta los seis meses, con valores de 63 y 89 g en PF y PI, respectivamente; sin diferencias significativas con el testigo (p ≤ 0.05). El DSC alcanzó valores del 66 % al 87 % en HTPF como HTPI a los seis meses, respectivamente. Estos resultados demuestran la habilidad del L. hexandra para desarrollar una rizósfera con alta densidad de BFN, producir biomasa vegetal y fitorremediar Gleysoles con petróleo fresco e intemperizado en ambientes tropicales inundados.

Abstract:The oil industry has generated chronic oil spills and their accumulation in wetlands of the state of Tabasco, in Southeastern Mexico. Waterlogging is a factor that limits the use of remediation technologies because of its high cost and low levels of oil degradation. However, Leersia hexandra is a grass that grows in these contaminated areas with weathered oil. The aim of the study was to evaluate the bacteria density, plant biomass production and phytoremediation of L. hexandra in contaminated soil. For this, two experiments in plastic tunnel were performed with fresh (E1) and weathered petroleum (E2) under waterlogging experimental conditions. The E1 was based on eight doses: 6 000, 10 000, 30 000, 60 000, 90 000, 120 000, 150 000 and 180 000 mg.kg-1 dry basis (d. b.) of total petroleum hydrocarbons fresh (TPH-F), and the E2, that evaluated five doses: 14 173, 28 400, 50 598, 75 492 and 112 142 mg. kg-1 d. b. of total petroleum hydrocarbons weathered (TPH-W); a control treatment with 2 607 mg.kg-1 d. b. was used. Each experiment, with eight replicates per treatment, evaluated after three and six months: a) microbial density of total free-living nitrogen-fixing bacteria (NFB) of Azospirillum (AZP) and Azotobacter group (AZT), for viable count in serial plate; b) dry matter production (DMP), quantified gravimetrically as dry weight of L. hexandra; and c) the decontamination percentage of hydrocarbons (PDH) by Soxhlet extraction. In soil with TPH-F, the NFB, AZP y AZT populations were stimulated five times more than the control both at the three and six months; however, concentrations of 150 000 and 180 000 mg.kg-1 d. b. inhibited the bacterial density between 70 and 89 %. Likewise, in soil with TPH-W, the FNB, AZP and AZT inhibitions were 90 %, with the exception of the 14 173 mg.kg-1 d. b. treatment, which stimulated the NFB and AZT in 2 and 0.10 times more than the control, respectively. The DMP was continued at the six months in the experiments, with values of 63 and 89 g in fresh and weathered petroleum, respectively; had no significant differences with the control (p≤0.05). The PDH reached values of 66 to 87 % both TPH-F and TPH-W at six months, respectively. These results demonstrated the ability the L. hexandra rhizosphere to stimulate the high NFB density, vegetal biomass production and phytoremediation of contaminated soils (with fresh and weathered petroleum), in a tropical waterlogging environment. Rev. Biol. Trop. 65 (1): 21-30. Epub 2017 March 01.

Estresse psicossocial no trabalho e o padrão de consumo de álcool em trabalhadores offshore / Psychosocial stress at work and alcohol consumption patterns in offshore oil workers / Estrés psicosocial en el trabajo y patrón de consumo de alcohol en trabajadores offshore

Resumo: Os objetivos foram avaliar a associação entre o estresse psicossocial no trabalho e o padrão de consumo de álcool em trabalhadores offshore. Trata-se de um estudo transversal realizado com 210 prestadores de serviço em instalações petrolíferas situadas no Estado do Rio de Janeiro, Brasil, entre julho e setembro de 2014. O instrumento de coleta consistiu em um questionário multidimensional autopreenchido. A exposição ao estresse foi avaliada segundo o modelo demanda-controle e o padrão de consumo de álcool foi avaliado pelo instrumento AUDIT (Alcohol Use Disorders Identification Test). As análises estatísticas se basearem no modelo de regressão logística multivariado. Os participantes têm, em média 32,9 anos (desvio padrão ± 8,1 anos). A maioria é casada (62,9%) e relata ter religião (84,5%); 15,2% apresentam consumo abusivo de álcool, 20,3% completaram o Ensino Superior e 56,6% têm menos de 5 anos de experiência no campo offshore. Todos os participantes estão submetidos ao esquema de turnos de trabalho de 12 horas diárias ao longo de 15 dias seguidos por 15 dias de folga, 62,4% trabalham em turnos fixos. As análises multivariadas mostraram que trabalhadores expostos ao alto estresse no trabalho (RC = 3,30; IC95%: 1,18-9,27) têm maior chance de apresentar consumo abusivo de álcool quando comparados aos trabalhadores não expostos. Os resultados apresentados contribuem para o maior entendimento de um tema ainda controverso na literatura, qual seja, a relação entre o estresse psicossocial e o consumo de álcool, e apontam para a necessidade de novas investigações.

Abstract: The objectives were to assess the association between psychosocial stress at work and alcohol consumption patterns in offshore oil workers. This was a cross-sectional study of 210 workers on offshore oil rigs in the state of Rio de Janeiro, Brazil, from July to September 2014. The data collection instrument was a self-completed multidimensional questionnaire. Exposure to stress was measured by the demand-control model and alcohol consumption pattern was measured with the Alcohol Use Disorders Identification Test (AUDIT). Statistical analyses were based on the multivariate logistic regression model. Participants' mean age was 32.9 years (SD ± 8.1 years). Most were married (62.9%) and reported having a religion (84.5%); 15.2% reported abusive levels of alcohol consumption, 20.3% had finished university, and 56.6% had fewer than 5 years of offshore experience. All the participants were subject to 12-hour daily shifts for 15 days followed by 15 days off, and 62.4% worked on fixed shifts. The multivariate analyses showed that workers exposed to workplace stress (OR = 3.30; 95%CI: 1.18-9.27) had higher odds of alcohol abuse when compared to unexposed workers. The results help elucidate what is still a controversial issue in the literature, i.e., the relationship between psychosocial stress and alcohol consumption, and point to the need for further studies.

Resumen: Los objetivos fueron evaluar la asociación entre el estrés psicosocial en el trabajo y el padrón de consumo de alcohol en trabajadores offshore. Se trata de un estudio transversal, realizado con 210 prestadores de servicio en instalaciones petrolíferas, situadas en el estado de Río de Janeiro, Brasil, entre julio y septiembre de 2014. El instrumento de recogida consistió en un cuestionario multidimensional autocompletado. La exposición al estrés se evaluó según el modelo demanda-control y el patrón de consumo de alcohol se evaluó mediante el instrumento AUDIT (Alcohol Use Disorders Identification Test). Los análisis estadísticos se basaron en el modelo de regresión logística multivariada. Los participantes tienen de media 32,9 años (desvío patrón ± 8,1 años). La mayoría está casada (62,9%) e informa tener alguna religión (84,5%); un 15,2% presentan un consumo abusivo de alcohol, un 20,3% completaron la enseñanza superior y un 56,6% tiene menos de 5 años de experiencia en el campo offshore. Todos los participantes están sometidos al esquema de turnos de trabajo de 12 horas diarias, a lo largo de 15 días seguidos, de 15 días de vacaciones, y un 62,4% trabaja en turnos fijos. Los análisis multivariados mostraron que los trabajadores expuestos a un alto estrés en el trabajo (RC = 3,30; IC95%: 1,18-9,27) tienen una mayor oportunidad de presentar consumo abusivo de alcohol, cuando se les compara con los trabajadores no expuestos. Los resultados presentados contribuyen a un mayor entendimiento de un tema todavía controvertido en la literatura, sea cual sea: la relación entre el estrés psicosocial y el consumo de alcohol, que apunta la necesidad de nuevas investigaciones sobre el tema.

Evaluation of bacterial diversity recovered from petroleum samples using different physical matrices

ABSTRACT Unraveling the microbial diversity and its complexity in petroleum reservoir environments has been a challenge throughout the years. Despite the techniques developed in order to improve methodologies involving DNA extraction from crude oil, microbial enrichments using different culture conditions can be applied as a way to increase the recovery of DNA from environments with low cellular density for further microbiological analyses. This work aimed at the evaluation of different matrices (arenite, shale and polyurethane foam) as support materials for microbial growth and biofilm formation in enrichments using a biodegraded petroleum sample as inoculum in sulfate reducing condition. Subsequent microbial diversity characterization was carried out using Scanning Electronic Microscopy (SEM), Denaturing Gradient Gel Electrophoresis (DGGE) and 16S rRNA gene libraries in order to compare the microbial biomass yield, DNA recovery efficiency and diversity among the enrichments. The DNA from microbial communities in petroleum enrichments was purified according to a protocol established in this work and used for 16S rRNA amplification with bacterial generic primers. The PCR products were cloned, and positive clones were screened by Amplified Ribosomal DNA Restriction Analysis (ARDRA). Sequencing and phylogenetic analyses revealed that the bacterial community was mostly represented by members of the genera Petrotoga, Bacillus, Pseudomonas, Geobacillus and Rahnella. The use of different support materials in the enrichments yielded an increase in microbial biomass and biofilm formation, indicating that these materials may be employed for efficient biomass recovery from petroleum reservoir samples. Nonetheless, the most diverse microbiota were recovered from the biodegraded petroleum sample using polyurethane foam cubes as support material.

Sphingomonas from petroleum-contaminated soils in Shenfu, China and their PAHs degradation abilities

Abstract Members of the Sphingomonas genus are often isolated from petroleum-contaminated soils due to their unique abilities to degrade polycyclic aromatic hydrocarbons (PAHs), which are important for in situ bioremediation. In this study, a combined phenotypic and genotypic approach using streptomycin-containing medium and Sphingomonas -specific PCR was developed to isolate and identify culturable Sphingomonas strains present in petroleum-contaminated soils in the Shenfu wastewater irrigation zone. Of the 15 soil samples examined, 12 soils yielded yellow streptomycin-resistant colonies. The largest number of yellow colony-forming units (CFUs) could reach 105 CFUs g-1 soil. The number of yellow CFUs had a significant positive correlation (p < 0.05) with the ratio of PAHs to total petroleum hydrocarbons (TPH), indicating that Sphingomonas may play a key role in degrading the PAH fraction of the petroleum contaminants at this site. Sixty yellow colonies were selected randomly and analyzed by colony PCR using Sphingomonas -specific primers, out of which 48 isolates had PCR-positive signals. The 48 positive amplicons generated 8 distinct restriction fragment length polymorphism (RFLP) patterns, and 7 out of 8 phylotypes were identified as Sphingomonas by 16S rRNA gene sequencing of the representative strains. Within these 7 Sphingomonas strains, 6 strains were capable of using fluorene as the sole carbon source, while 2 strains were phenanthrene-degrading Sphingomonas. To the best of our knowledge, this is the first report to evaluate the relationship between PAHs contamination levels and culturable Sphingomonas in environmental samples.

Effects of water-soluble fraction of petroleum on growth and prey consumption of juvenile Hoplias aff. malabaricus (Osteichthyes: Erythrinidae) / Efeitos da fração solúvel de petróleo no crescimento e consumo em juvenis de Hoplias aff. malabaricus (Osteichthyes: Erythrinidae)

Abstract The influence of the water-soluble fraction of petroleum (WSF) on prey consumption and growth of juvenile trahira Hoplias aff. malabaricus was investigated. Juveniles were submitted to either WSF or Control treatment over 28 days, and jewel tetra Hyphessobrycon eques adults were offered daily as prey for each predator. Total prey consumption ranged from 16 to 86 individuals. Despite the initially lower prey consumption under WSF exposure, there were no significant differences in overall feeding rates between the two treatments. Water-soluble fraction of petroleum had a negative effect on the growth in length of H. aff. malabaricus juveniles. Although unaffected, prey consumption suggested a relative resistance in H. aff. malabaricus to WSF exposition and the lower growth of individuals exposed to WSF than the Control possibly reflects metabolic costs. The implications of the main findings for the individual and the food chain are discussed, including behavioral aspects and the role played by this predator in shallow aquatic systems.

Resumo A influência da fração solúvel de petróleo (FSP) no consumo de presas e crescimento de juvenis da traíra Hoplias aff. malabaricus foi investigada. Os juvenis foram submetidos aos tratamentos FSP e Controle durante 28 dias, e adultos de matogrosso Hyphessobrycon eques foram oferecidos diariamente como presa para cada predador. O total de presas consumidas variou de 16 a 86 indivíduos. Apesar do menor consumo inicial de presas sob exposição de FSP, não houve diferenças significativas nas taxas de consumo entre os dois tratamentos. A FSP teve um efeito negativo no crescimento em tamanho de juvenis de H. aff. malabaricus. Embora a ausência de efeito no consumo de presas sugira uma relativa resistência de H. aff. malabaricus à exposição à FSP, o menor crescimento em tamanho dos indivíduos expostos ao poluente reflete possivelmente custos metabólicos. As implicações dos principais resultados nos níveis do organismo e da cadeia alimentar são discutidos, incluindo aspectos comportamentais e o papel desempenhado por este predador em ecossistemas aquáticos rasos.