Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “PETROLEUM”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 883 records · Page 49Linked to original sources

Biodegradation of petroleum products in experimental plots in Antarctic marine sediments is location dependent.

Clean sediment collected from O'Brien Bay, East Antarctica, was artificially contaminated with a mix of Special Antarctic Blend diesel fuel and lubricating oil and deployed in two uncontaminated locations (O'Brien and Sparkes Bays) and a previously contaminated bay (Brown Bay) to evaluate whether a history of prior contamination would influence the biodegradation process. Detailed analysis of the hydrocarbon composition in the sediment after 11 weeks revealed different patterns of degradation in each bay. Biodegradation indices showed that hydrocarbon biodegradation occurred in all three bays but was most extensive in Brown Bay. This study shows that even within a relatively small geographical area, the longevity of hydrocarbons in Antarctic marine sediments can be variable. Our results are consistent with faster natural attenuation of spilt oil at sites with previous exposure to oil but further work is needed to confirm this. Such information would be useful when evaluating the true risk and longevity of oils spills.

Antarctic Regions↗

Life cycle assessment of wastewater treatment technologies treating petroleum process waters.

This paper describes the implementation of life cycle assessment to investigate the environmental impact of 20 technologies suitable for treating extensive volumes of water produced during the oil and gas extraction processes. Data on the physical and operational attributes of technologies under consideration were assembled and their life cycle environmental impacts estimated over 15 year time period. The results were then incorporated in a decision support system which allows identification and prioritisation of potential technology combinations capable of producing water for nine designated industrial and agricultural end uses. In total, more than 618 technology combinations were investigated for their environmental impacts. The identification and prioritisation of technologies were done on the basis of their environmental and technical performance. This analysis showed that dissolved air flotation, absorbents, dual media filtration and reverse osmosis technologies offer relatively low environmental impact parts of systems for cleaning such process waters. Furthermore, the environmental assessment combined within the decision support system has revealed potentially valuable indirect downstream "benefits" from effects such as evaporative losses from wetlands in terms of the overall environmental impact of a treatment system.

Extraction and Processing Industry↗

Spatial and temporal trends of petroleum hydrocarbons in wild mussels from the Galician coast (NW Spain) affected by the Prestige oil spill.

Polycyclic aromatic hydrocarbons (PAHs) were determined in tissues of wild mussels (Mytilus galloprovincialis) from the Galicia coast (NW Spain) in order to assess the extent of the environmental impact caused by the Prestige oil spill (November 13, 2002). Three sampling campaigns were carried out in February, June and November 2003 at 24 stations along the Galicia coast, from La Guardia (Pontevedra) to Ribadeo (Lugo). The spatial distribution of PAHs found in the first sampling period, clearly revealed the central area (Costa da Morte) as the most affected by the oil spill. In these stations, concentrations up to 7780 microg/kg dw of the sum of 13 parent PAHs were found 2-3 months after the spill. Molecular parameters within the aliphatic and aromatic fractions confirmed the presence of the Prestige oil in these samples. The levels markedly decreased at most of the stations in the second sampling and recovered to levels found before the spill in November 2003, 1 year after the accident (29-279 microg/kg dw, av. 133+/-83 microg/kg dw). However, a certain increase was observed in some sites which could be related to the remobilization of oil residues from still unclean intertidal spots or sediments due to the winter marine weather conditions.

Animals↗

Geobacillus jurassicus sp. nov., a new thermophilic bacterium isolated from a high-temperature petroleum reservoir, and the validation of the Geobacillus species.

Four thermophilic, spore-forming bacterial strains, DS1(T), DS2, 46 and 49, were isolated from the high-temperature Dagang oilfield, located in China. The strains were identified by using the polyphasic taxonomy approach. These were aerobic, gram-positive, rod-shaped, moderately thermophilic (with an optimum growth temperature of 60-65 degrees C), chemoorganotrophic bacteria capable of growing on various sugars, carboxylic acids and crude oil. Two strains, DS1(T) and DS2, were capable of growing on individual saturated hydrocarbons. The G + C content of the DNA of strains DS1(T) and DS2 was 54.5 and 53.8 mol%, respectively. The phylogenetic analysis of the 16S rDNA of strains DS1(T) and DS2 showed that they form a separate cluster within the genus Geobacillus. The cellular fatty acids of the isolates were dominated by iso-15:0, iso-16:0 and iso-17:0 acids, which are the typical fatty acids of bacteria from the genus Geobacillus. The DNA-DNA hybridization study and the comparative analysis of the morphological and chemotaxonomic characteristics of strains DS1(T) and DS2 showed that they differ from the previously described Geobacillus species and belong to a new species, which was called Geobacillus jurassicus. DS1(T) (=VKM B2301(T), = DSM 15726(T)) is the type strain of this species. According to both DNA-DNA reassociation studies and 16S rDNA sequence analysis, two other strains, 46 and 49, were assigned to the species G. stearothermophilus. In this paper, we provide evidence that the new combinations G. stearothermophilus, G. thermoleovorans, G. kaustophilus, G. thermoglucosidasius and G. thermodenitrificans may be considered to be valid.

Aerobiosis↗

Cosolvency effect in subsurface systems contaminated with petroleum hydrocarbons and ethanol.

In Brazil, most gas stations and terminals store tanks containing hydrated ethanol, gasohol and diesel. In case of spills, it is possible that a high aqueous ethanol concentration can facilitate the transfer of hydrocarbons into the aqueous phase, enhancing contaminant concentrations in groundwater, a process called cosolvency. This study investigates the cosolvency effect of ethanol on the aqueous solubility of mono- and polycyclic aromatic hydrocarbons, and presents a simple log-linear model to predict this effect under equilibrium conditions. Cosolvency experiments were carried out in batch reactors under equilibrium conditions for pure mono- and polycyclic aromatic hydrocarbons, gasohol and diesel. A linear relationship between cosolvency power and Kow was determined, which allows predictions of the increase of aromatic hydrocarbon solubility due to the presence of ethanol. Results indicate that cosolvency would be significant only for high aqueous ethanol concentrations (higher than 10%). Under these conditions, cosolvency may be critical only in cases of large gasohol spills or in simultaneous releases of neat ethanol and other fuels. In this way, the hydrophobic and toxic polycyclic aromatic hydrocarbons (PAHs), that are usually present in minor aqueous concentrations in fuel spills without ethanol, may be dissolved in larger amounts in groundwater.

Brazil↗

Toxicity of petroleum crude oils and their effect on xenobiotic metabolizing enzyme activities in the chicken embryo in ovo.

Microliter quantities of a Prudhoe Bay crude oil (PBCO) applied to the shell of fertile chick eggs during various stages of development induced cytochrome P-450 levels and mixed-function oxidase activities within the liver of the embryo. PBCO (5 microliter) applied on Day 11 of incubation was found to maximally induce within 24 hr embryo hepatic cytochrome P-450 levels (fourfold), naphthalene hydroxylase (sixfold), benzo[a]pyrene 3-hydroxylase (14-fold), and 7-ethoxyresorufin O-deethylase (24-fold). Glutathione S-transferase was not induced. Crude oils are known to be highly toxic to avian embryos, especially during the early stages of development. The LD50 of PBCO and Hibernia crude oil applied to the egg shell on Day 8 of incubation was found to be 1.3 and 2.2 microliter, respectively. Mixed-function oxidase-dependent metabolism of crude oil components may be required for toxicity since administration of 20 micrograms of disulfiram in dioxane 1 hr prior to application of 1.3 microliter of PBCO reduced embryo mortality from 60 to 20%.

Animals↗

Quantification of petroleum-type hydrocarbons in avian tissue.

Methods were developed for the analysis of 16 hydrocarbons in avian tissue. Mechanical extraction with pentane was followed by clean-up on Florisil and Silicar. Residues were determined by gas-liquid chromatography and gas-liquid, chromatography-mass spectrometry. The method was applied to the analysis of liver, kidney, fat, and brain tissue of mallard ducks (Anas platyrhynchos) fed a mixture of hydrocarbons. Measurable concentrations of all compounds analyzed were present in all tissues except brain. Highest concentrations were in fat.

Adipose Tissue↗

Long-term fate and persistence of the spilled metula oil in a marine salt marsh environment degradation of petroleum biomarkers.

Three coastal sites, heavily oiled from the 1974 Metula oil spill in the Strait of Magellan [two are salt marshes (East and West) and the third, an intertidal asphalt pavement], were examined during May 1998. Complete 'total oil analyses' were performed on the oil samples collected from these sites. Chemical fingerprinting data reveal, except for those samples from the East Marsh untreated plots which were only lightly to moderately weathered, that the spilled oil has undergone significant alteration in chemical composition after 24 years. There are no fundamental differences between the heavily weathered West Marsh and treated East Marsh samples. However, the effect of experimental filling action conducted in 1993 has been to substantially promote plant recolonization. The asphalt pavement samples indicate extremely high degradation of oil hydrocarbons, evidenced by a complete loss of n-alkanes from n-C8 to n-C41 and by depletion of greater than 98% of the alkylated polycyclic aromatic hydrocarbon homologues. Even the most refractory biomarker compounds showed some degree of biodegradation. The biomarkers were generally degraded in the declining order of importance as follows: diasteranes>C27 steranes>tricyclic terpanes>pentacyclic terpanes>norhapanes approximately C29-alphabetabeta-steranes.

Oils↗

Liquid chromatographic determination of benzo[a]pyrene at part-per-billion concentrations in highly refined coal- and petroleum-derived fuels.

Benzo[a]pyrene (BaP), a well-known carcinogen, is frequently measured as an "indicator" of the potential dermal tumorigenicity of a sample. The present sequential high-performance liquid chromatography--high-performance liquid chromatography method overcomes problems in trace-level sample enrichment and recovery corrections encountered earlier. An amount of 5 g of naphtha or fuel oil is diluted to 10 ml with dichloromethane and spiked with a small quantity (ca. 0.25 micrograms) of 14C-labeled BaP tracer. A BaP-enriched fraction is obtained from a 1-ml aliquot of this sample by semipreparative chromatography on a Partisil PAC 10 column with dichloromethane-hexane (10:90) as the eluent, and concentrated to exactly 0.3, 0.5, or 1.0 ml in acetonitrile. Quantitation is performed using a reversed-phase Vydac 201 TP 5415 column with acetonitrile-water (75:25) as eluent and a Waters Model 420 E/420 AC fluorescence detector, employing an excitation/emission filter pair of 360/425 nm. The recovery of the radiolabeled tracer is evaluated by combustion of 50 microliter of the final isolate in pure oxygen, collection of the liberated 14CO2 in an alkaline desorber, and liquid scintillation counting. The recovery of BaP normally exceeded 90%, but values as low as ca. 50% were occasionally observed. Potential matrix interferences in the recovery determination were eliminated by sample combustion. The nominal precision of the overall method is approximately +/- 30% relative standard deviation at a BaP concentration of 30 ppb. The nominal analysis time for a single sample is approximately 4 h.

Benzo(a)pyrene↗

Biodegradation of petroleum hydrocarbons at low temperature in the presence of the dispersant Corexit 9500.

Our study examined the effects of Corexit 9500 and sediment on microbial mineralization of specific aliphatic and aromatic hydrocarbons found in crude oil. We also measured gross mineralization of crude oil, dispersed crude oil and dispersant by a marine microbial consortium in the absence of sediment. When provided as carbon sources, our consortium mineralized Corexit 9500 the most rapidly, followed by fresh oil, and finally weathered oil or dispersed oil. However, mineralization in short term assays favored particular components of crude oil (2-methyl-naphthalene > dodecane > phenanthrene > hexadecane > pyrene) and was not affected by addition of nutrients or sediment (high sand, low organic carbon). Adding dispersant inhibited hexadecane and phenanthrene mineralization but did not affect dodecane and 2-methyl-naphthalene mineralization. Thus, the effect of dispersant on biodegradation of a specific hydrocarbon was not predictable by class. The results were consistent for both high and low oiling experiments and for both fresh and weathered oil. Overall, our results indicate that environmental use of Corexit 9500 could result in either increases or decreases in the toxicity of residual oil through selective microbial mineralization of hydrocarbons.

Bacteria↗

Study on the fate of petroleum-derived polycyclic aromatic hydrocarbons (PAHs) and the effect of chemical dispersant using an enclosed ecosystem, mesocosm.

Polycyclic Aromatic Hydrocarbons (PAHs) are one of the components found in oil and are of interest because some are toxic. We studied the environmental fate of PAHs and the effects of chemical dispersants using experimental 500 l mesocosm tanks that mimic natural ecosystems. The tanks were filled with seawater spiked with the water-soluble fraction of heavy residual oil. Water samples and settling particles in the tanks were collected periodically and 38 PAH compounds were analyzed by gas chromatography-mass spectrometry (GC-MS). Low molecular weight (LMW) PAHs with less than three benzene rings disappeared rapidly, mostly within 2 days. On the other hand, high molecular weight (HMW) PAHs with more than four benzene rings remained in the water column for a longer time, up to 9 days. Also, significant portions (10-94%) of HMW PAHs settled to the bottom and were caught in the sediment trap. The addition of chemical dispersant accelerated dissolution and biodegradation of PAHs, especially HMW PAHs. The dispersant amplified the amounts of PAHs found in the water column. The amplification was the greater for the more hydrophobic PAHs, with an enrichment factor of up to six times. The increased PAHs resulting from dispersant use overwhelmed the normal degradation and, as a result, higher concentrations of PAHs were observed in water column throughout the experimental period. We conclude that the addition of the dispersant could increase the concentration of water column PAHs and thus increase the exposure and potential toxicity for organisms in the natural environment. By making more hydrocarbon material available to the water column, the application of dispersant reduced the settling of PAHs. For the tank with dispersant, only 6% of chrysene initially introduced was detected in the sediment trap whereas 70% was found in the trap in the tank without dispersant.

Accidents↗

Persistence of petroleum hydrocarbon contamination in sediments of the canals in Venice, Italy: 1995 and 1998.

Total hydrocarbon and selected polycyclic aromatic hydrocarbon (PAH) levels were examined in sediments collected from known problematic areas in the canals of Venice, Italy, in 1995 and 1998. Hydrocarbon concentrations were greatest in the interior canals, moderate in the partially enclosed locations and lowest in the open-water sites. Total hydrocarbon and PAH concentrations declined from 1995 to 1998. Ancillary data suggest that this decline may have been in response to the elimination of many industrial activities in the lagoon and to initiating an aggressive canal dredging program. The distributions of individual components were generally similar both years regardless of the total PAH concentration or the location of sample collected. PAH alkyl homolog distributions suggest that atmospheric deposition of petrochemical combustion products is the main source of PAHs to Venice's sediments. In some cases however, the presence of low levels of the two-ring naphthalene homologous series indicate additional low-level inputs of fresh oil.

Cities↗

Influence of n-alkanes and petroleum on fatty acid composition of a hydrocarbonoclastic bacterium: Marinobacter hydrocarbonoclasticus strain 617.

This study concerns the effects of various long-chain n-alkanes, n-alkane mixtures and Arabian Light crude oil on the fatty acid (FA) composition of a sedimentary marine bacteria (Marinobacter hydrocarbonoclasticus strain 617), growing under aerobic conditions. The cultures with n-alkanes, as compared with soluble carbon sources, led to greater amounts of saturated and methyl branched FA (mainly belonging to a delta10 series). We observed the appearance or increase of saturated and unsaturated FA with the same carbon chain length (CCL) as the n-alkane carbon source (maximum for n-alkane CCL corresponding to the 'range' of the de novo synthesized fatty acids). We also observed a strong control of the oddness/evenness of the CCL of the FA by the oddness/evenness of the n-alkane. A n-alkane utilization index, (saturated + branched)/monounsaturated fatty acids (SAFA + BFA/MUFA) enabled discriminating between soluble carbon sources and hydrocarbons.

Alkanes↗