Young man with severe metabolic acidosis after transformer oil ingestion: a case report.

BACKGROUND: Transformer oil is used in oil-filled transformers for its insulating as well as coolant properties. Transformer oil ingestion for attempted suicide is seldom heard of. Our patient's case presented us with a major diagnostic as well as treatment challenge because we encountered such a case for the first time and were totally unaware of the fact that methanol might make up the main component of an aged transformer oil. CASE PRESENTATION: A 19-year-old Pakistani/Asian man was brought to our hospital with altered sensorium. He was found to have elevated anion gap acidosis, increased osmolal gap, and acute kidney injury. He had no evidence of rhabdomyolysis or hemolysis. Computed tomography of his head showed cerebral edema. He was resuscitated with intravenous fluids and bicarbonate. Three days later, he confessed taking transformer oil with suicidal intention. His clinical picture mimicked acute methanol intoxication. With an initial improvement in his neurological status, he started complaining of constant headache with episodes of agitation and delirium. His renal function continued worsening despite an adequate urine output. He showed a remarkable improvement in his neurological state after just one session of hemodialysis. CONCLUSIONS: There is evidence that aged transformer oil contains methanol, and a patient who consumes it can present with features mimicking acute methanol intoxication.

Development and Evaluation of Surfactant Nanocapsules for Chemical Enhanced Oil Recovery (EOR) Applications.

The primary objective of this study is the synthesis of nanocapsules (NC) that allow the reduction of the adsorption process of surfactant over the porous media in enhanced oil recovery processes. Nanocapsules were synthesized through the nanoprecipitation method by encapsulating commercial surfactants Span 20 and Petro 50, and using type II resins isolated from vacuum residue as a shell. The NC were characterized using dynamic light scattering, transmission electron microscopy, Fourier transform infrared, solvency tests, softening point measurements and entrapment efficiency. The obtained NC showed spherical geometry with sizes of 71 and 120 nm for encapsulated Span 20 (NCS20), and Petro 50 surfactant (NCP50), respectively. Also, the NCS20 is composed of 90% of surfactant and 10% of type II resins, while the NCP50 material is 94% of surfactant and 6% of the shell. Nanofluids of nanocapsules dispersed in deionized water were prepared for evaluating the nanofluid­sandstone interaction from adsorption phenomena using a batch-mode method, contact angle measurements, and FTIR analysis. The results showed that NC adsorption was null at the different conditions of temperatures evaluated of 25, 50, and 70 °C, and stirring velocities up to 10,000 rpm. IFT measurements showed a reduction from 18 to 1.62 and 0.15 mN/m for the nanofluids with 10 mg/L of NCS20, and NCP50 materials, respectively. Displacements tests were conducted using a 20 °API crude oil in a quarter five-spot pattern micromodel and showed an additional oil recovery of 23% in comparison with that of waterflooding, with fewer pore volumes injected than when using a dissolved surfactant.

Genome annotation and comparative genomic analysis of Bacillus subtilis MJ01, a new bio-degradation strain isolated from oil-contaminated soil.

One of the main challenges in elimination of oil contamination from polluted environments is improvement of biodegradation by highly efficient microorganisms. Bacillus subtilis MJ01 has been evaluated as a new resource for producing biosurfactant compounds. This bacterium, which produces surfactin, is able to enhance bio-accessibility to oil hydrocarbons in contaminated soils. The genome of B. subtilis MJ01 was sequenced and assembled by PacBio RS sequencing technology. One big contig with a length of 4,108,293 bp without any gap was assembled. Genome annotation and prediction of gene showed that MJ01 genome is very similar to B. subtilis spizizenii TU-B-10 (95% similarity). The comparison and analysis of orthologous genes carried out between B. subtilis MJ01, reference strain B. subtilis subsp. subtilis str. 168, and close relative spizizenii TU-B-10 by microscope platform and various bioinformatics tools. More than 88% of 4269 predicted coding sequences in MJ01 had at least one similar sequence in genome of reference strain and spizizenii TU-B-10. Despite this high similarity, some differences were detected among encoding sequences of non-ribosome protein and bacteriocins in MJ01 and spizizenii TU-B-10. MJ01 has unique nucleotide sequences and a novel predicted lasso-peptide bacteriocin; it also has not any similar nucleotide sequence in non-redundant nucleotide data base.

Functional assessment of plant and microalgal lipid pathway genes in yeast to enhance microbial industrial oil production.

As promising alternatives to fossil-derived oils, microbial lipids are important as industrial feedstocks for biofuels and oleochemicals. Our broad aim is to increase lipid content in oleaginous yeast through expression of lipid accumulation genes and use Saccharomyces cerevisiae to functionally assess genes obtained from oil-producing plants and microalgae. Lipid accumulation genes DGAT (diacylglycerol acyltransferase), PDAT (phospholipid: diacylglycerol acyltransferase), and ROD1 (phosphatidylcholine: diacylglycerol choline-phosphotransferase) were separately expressed in yeast and lipid production measured by fluorescence, solvent extraction, thin layer chromatography, and gas chromatography (GC) of fatty acid methyl esters. Expression of DGAT1 from Arabidopsis thaliana effectively increased total fatty acids by 1.81-fold above control, and ROD1 led to increased unsaturated fatty acid content of yeast lipid. The functional assessment approach enabled the fast selection of candidate genes for metabolic engineering of yeast for production of lipid feedstocks.

Biodegradation of dispersed oil in seawater is not inhibited by a commercial oil spill dispersant.

Chemical dispersants are well-established as oil spill response tools. Several studies have emphasized their positive effects on oil biodegradation, but recent studies have claimed that dispersants may actually inhibit the oil biodegradation process. In this study, biodegradation of oil dispersions in natural seawater at low temperature (5°C) was compared, using oil without dispersant, and oil premixed with different concentrations of Slickgone NS, a widely used oil spill dispersant in Europe. Saturates (nC10-nC36 alkanes), naphthalenes and 2- to 5-ring polycyclic aromatic hydrocarbons (PAH) were biotransformed at comparable rates in all dispersions, both with and without dispersant. Microbial communities differed primarily between samples with or without oil, and they were not significantly affected by increasing dispersant concentrations. Our data therefore showed that a common oil spill dispersant did not inhibit biodegradation of oil at dispersant concentrations relevant for response operations.

Offline Solid-phase Extraction Large-volume Injection-Gas chromatography for the Analysis of Mineral Oil-saturated Hydrocarbons in Commercial Vegetable Oils.

An offline solid-phase extraction (SPE) approach combined with a large-volume injection (LVI)-gas chromatography-flame ionization detector (LVI-GC-FID) is improved for routine analysis of mineral oil saturated hydrocarbons (MOSH) in vegetable oils. The key procedure of the method consists in using offline SPE columns for MOSH purification. The SPE column packed with 1% Ag-activated silica gel was used to separate MOSH from triglycerides and olefins in variety of vegetable oils. The eluent of MOSH fraction was only 3 mL and the concentration step was quick with little evaporation loss. The limit of quantification (LOQ) of the method was 2.5 mg/kg and the linearity ranged from 2 to 300 mg/kg. The accuracy was assessed by measuring the recoveries from spiked oil samples and was higher than 90%. Twenty-seven commercial vegetable oils were analyzed, and different levels of MOSH contamination were detected with the highest being 259.4 mg/kg. The results suggested that it is necessary to routinely detect mineral oil contamination in vegetable oils for food safety.

A new nanocomposite forward osmosis membrane custom-designed for treating shale gas wastewater.

Managing the wastewater discharged from oil and shale gas fields is a big challenge, because this kind of wastewater is normally polluted by high contents of both oils and salts. Conventional pressure-driven membranes experience little success for treating this wastewater because of either severe membrane fouling or incapability of desalination. In this study, we designed a new nanocomposite forward osmosis (FO) membrane for accomplishing simultaneous oil/water separation and desalination. This nanocomposite FO membrane is composed of an oil-repelling and salt-rejecting hydrogel selective layer on top of a graphene oxide (GO) nanosheets infused polymeric support layer. The hydrogel selective layer demonstrates strong underwater oleophobicity that leads to superior anti-fouling capability under various oil/water emulsions, and the infused GO in support layer can significantly mitigate internal concentration polarization (ICP) through reducing FO membrane structural parameter by as much as 20%. Compared with commercial FO membrane, this new FO membrane demonstrates more than three times higher water flux, higher removals for oil and salts (>99.9% for oil and >99.7% for multivalent ions) and significantly lower fouling tendency when investigated with simulated shale gas wastewater. These combined merits will endorse this new FO membrane with wide applications in treating highly saline and oily wastewaters.

Effect of oil droplet size on activation energy for coalescence of oil droplets in an O/W emulsion.

The activation energy of a reasonable order of magnitude was estimated for the coalescence of oil droplets in an O/W emulsion by formulating the balance of forces acting on a droplet that crosses over the potential barrier to coalesce with another droplet by the DLVO theory and Stokes' law. An emulsion with smaller oil droplets was shown to be more stable.

[MICROBIAL DESTRUCTION MINERAL (OIL) MOTOR OIL].

In a review information is presented about composition of mineral motor oils and their negative impact on the environment and the ability of microorganisms, in particular actinobacteria, to assimilate hydrocarbon oil components. The role of bacteria is described in the process of cleaning up polluted environments motor oils and the prospect of their use in biotechnology, environmental clean-up of these pollutants.

Agent orange herbicides, organophosphate and triazinic pesticides analysis in olive oil and industrial oil mill waste effluents using new organic phase immunosensors.

New immunosensors working in organic solvent mixtures (OPIEs) for the analysis of traces of different pesticides (triazinic, organophosphates and chlorurates) present in hydrophobic matrices such as olive oil were developed and tested. A Clark electrode was used as transducer and peroxidase enzyme as marker. The competitive process took place in a chloroform-hexane 50% (V/V) mixture, while the subsequent enzymatic final measurement was performed in decane and using tert-butylhydroperoxide as substrate of the enzymatic reaction. A linear response of between about 10nM and 5.0µM was usually obtained in the presence of olive oil. Recovery tests were carried out in commercial or artisanal extra virgin olive oil. Traces of pesticides were also checked in the oily matrix, in pomace and mill wastewaters from an industrial oil mill. Immunosensors show good selectivity and satisfactory precision and recovery tests performed in olive oil gave excellent results.

Estimation of the probability of exposure to machining fluids in a population-based case-control study.

We describe an approach for estimating the probability that study subjects were exposed to metalworking fluids (MWFs) in a population-based case-control study of bladder cancer. Study subject reports on the frequency of machining and use of specific MWFs (straight, soluble, and synthetic/semi-synthetic) were used to estimate exposure probability when available. Those reports also were used to develop estimates for job groups, which were then applied to jobs without MWF reports. Estimates using both cases and controls and controls only were developed. The prevalence of machining varied substantially across job groups (0.1->0.9%), with the greatest percentage of jobs that machined being reported by machinists and tool and die workers. Reports of straight and soluble MWF use were fairly consistent across job groups (generally 50-70%). Synthetic MWF use was lower (13-45%). There was little difference in reports by cases and controls vs. controls only. Approximately, 1% of the entire study population was assessed as definitely exposed to straight or soluble fluids in contrast to 0.2% definitely exposed to synthetic/semi-synthetics. A comparison between the reported use of the MWFs and U.S. production levels found high correlations (r generally >0.7). Overall, the method described here is likely to have provided a systematic and reliable ranking that better reflects the variability of exposure to three types of MWFs than approaches applied in the past. [Supplementary materials are available for this article. Go to the publisher's online edition of Journal of Occupational and Environmental Hygiene for the following free supplemental resources: a list of keywords in the occupational histories that were used to link study subjects to the metalworking fluids (MWFs) modules; recommendations from the literature on selection of MWFs based on type of machining operation, the metal being machined and decade; popular additives to MWFs; the number and proportion of controls who reported various MWF responses by job group; the number and proportion of controls assigned to the MWF types by job group and exposure category; and the distribution of cases and controls assigned various levels of probability by MWF type.].

Validation and comparison of two sampling methods to assess dermal exposure to drilling fluids and crude oil.

Dermal exposure to drilling fluids and crude oil is an exposure route of concern. However, there have been no published studies describing sampling methods or reporting dermal exposure measurements. We describe a study that aimed to evaluate a wipe sampling method to assess dermal exposure to an oil-based drilling fluid and crude oil, as well as to investigate the feasibility of using an interception cotton glove sampler for exposure on the hands/wrists. A direct comparison of the wipe and interception methods was also completed using pigs' trotters as a surrogate for human skin and a direct surface contact exposure scenario. Overall, acceptable recovery and sampling efficiencies were reported for both methods, and both methods had satisfactory storage stability at 1 and 7 days, although there appeared to be some loss over 14 days. The methods' comparison study revealed significantly higher removal of both fluids from the metal surface with the glove samples compared with the wipe samples (on average 2.5 times higher). Both evaluated sampling methods were found to be suitable for assessing dermal exposure to oil-based drilling fluids and crude oil; however, the comparison study clearly illustrates that glove samplers may overestimate the amount of fluid transferred to the skin. Further comparison of the two dermal sampling methods using additional exposure situations such as immersion or deposition, as well as a field evaluation, is warranted to confirm their appropriateness and suitability in the working environment.

Waste oil derived biofuels in China bring brightness for global GHG mitigation.

This study proposed a novel way for global greenhouse gas reduction through reusing China's waste oil to produce biofuels. Life cycle greenhouse gas mitigation potential of aviation bio-kerosene and biodiesel derived from China's waste oil in 2010 was equivalent to approximately 28.8% and 14.7% of mitigation achievements on fossil-based CO2 emissions by Annex B countries of the Kyoto Protocol in the period of 1990-2008, respectively. China's potential of producing biodiesel from waste oil in 2010 was equivalent to approximately 7.4% of China's fossil-based diesel usage in terms of energy. Potential of aviation bio-kerosene derived from waste oil could provide about 43.5% of China's aviation fuel demand in terms of energy. Sectors key to waste oil generation are identified from both production and consumption perspectives. Measures such as technology innovation, government supervision for waste oil collection and financial subsidies should be introduced to solve bottlenecks.

Phytoassessment of a waste engine oil-polluted soil exposed to two different intervals of monitored natural attenuation using African yam bean (Sphenostylis stenocarpa).

The present study comparatively investigated the phytotoxic effects of waste engine oil (WEO)-polluted soil exposed to monitored natural attenuation up to 5 and 14 months respectively. Soil was previously polluted with WEO at 0, 1, 2.5, 5 and 10% w/w oil in soil. Although, there was significant reduction in heavy metal concentration of soil as well as total hydrocarbon contents, performance of Sphenostylis stenocarpa was greatly retarded when sown at 5 months after pollution (MAP), with death of all seedlings except in the control. However, growth and yield performances were significantly (p > 0.05) enhanced at 14 MAP. Computation of hazard quotient showed that ecological risk factor initially posed by the presence of heavy metals in the soil at 5 MAP was significantly (p > 0.05) reduced to safe levels at 14 MAP.

Occupational exposure of air crews to tricresyl phosphate isomers and organophosphate flame retardants after fume events.

Aircraft cabin air can possibly be contaminated by tricresyl phosphates (TCP) from jet engine oils during fume events. o-TCP, a known neurotoxin, has been addressed to be an agent that might cause the symptoms reported by cabin crews after fume events. A total of 332 urine samples of pilots and cabin crew members in common passenger airplanes, who reported fume/odour during their last flight, were analysed for three isomers of tricresyl phosphate metabolites as well as dialkyl and diaryl phosphate metabolites of four flame retardants. None of the samples contained o-TCP metabolites above the limit of detection (LOD 0.5 µg/l). Only one sample contained metabolites of m- and p-tricresyl phosphates with levels near the LOD. Median metabolite levels of tributyl phosphate (TBP), tris-(2-chloroethyl) phosphate (TCEP) and triphenyl phosphate (TPP) (DBP 0.28 µg/l; BCEP 0.33 µg/l; DPP 1.1 µg/l) were found to be significantly higher than in unexposed persons from the general population. Median tris-(2-chloropropyl) phosphate (TCPP) metabolite levels were significantly not higher in air crews than in controls. Health complaints reported by air crews can hardly be addressed to o-TCP exposure in cabin air. Elevated metabolite levels for TBP, TCEP and TPP in air crews might occur due to traces of hydraulic fluid in cabin air (TBP, TPP) or due to release of commonly used flame retardants from the highly flame protected environment in the airplane. A slight occupational exposure of air crews to organophosphates was shown.

Identification of lubrication oil in the particulate matter emissions from engine exhaust of in-service commercial aircraft.

Lubrication oil was identified in the organic particulate matter (PM) emissions of engine exhaust plumes from in-service commercial aircraft at Chicago Midway Airport (MDW) and O'Hare International Airport (ORD). This is the first field study focused on aircraft lubrication oil emissions, and all of the observed plumes described in this work were due to near-idle engine operations. The identification was carried out with an Aerodyne high-resolution time-of-flight aerosol mass spectrometer (HR-ToF AMS) via a collaborative laboratory and field investigation. A characteristic mass marker of lubrication oil, I(85)/I(71), the ratio of ion fragment intensity between m/z = 85 and 71, was used to distinguish lubrication oil from jet engine combustion products. This AMS marker was based on ion fragmentation patterns measured using electron impact ionization for two brands of widely used lubrication oil in a laboratory study. The AMS measurements of exhaust plumes from commercial aircraft in this airport field study reveal that lubrication oil is commonly present in organic PM emissions that are associated with emitted soot particles, unlike the purely oil droplets observed at the lubrication system vent. The characteristic oil marker, I(85)/I(71), was applied to quantitatively determine the contribution from lubrication oil in measured aircraft plumes, which ranges from 5% to 100%.

Development of ultra-high erucic acid oil in the industrial oil crop Crambe abyssinica.

Erucic acid (22 : 1) is a major feedstock for the oleochemical industry. In this study, a gene stacking strategy was employed to develop transgenic Crambe abyssinica lines with increased 22 : 1 levels. Through integration of the LdLPAAT, BnFAE1 and CaFAD2-RNAi genes into the crambe genome, confirmed by Southern blot and qRT-PCR, the average levels of 18 : 1, 18 : 2 and 18 : 3 were markedly decreased and that of 22 : 1 was increased from 60% in the wild type to 73% in the best transgenic line of T4 generation. In single seeds of the same line, the 22 : 1 level could reach 76.9%, an increase of 28.0% over the wild type. The trierucin amount was positively correlated to 22 : 1 in the transgenic lines. Unlike high erucic rapeseed, the wild-type crambe contains 22 : 1 in the seed phosphatidylcholine and in the sn-2 position of triacylglycerols (5% and 8%, respectively). The transgenic line with high 22 : 1 had decreased 22 : 1 level in phosphatidylcholine, and this was negatively correlated with the 22 : 1 level at the sn-2 position of TAG. The significances of this study include (i) achieving an unprecedented level of 22 : 1 in an oil crop; (ii) disclosing mechanisms in the channelling of a triacylglycerol-specific unusual fatty acid in oil seeds; (iii) indicating potential limiting factors involved in the erucic acid biosynthesis and paving the way for further increase of this acid and (iv) development of an added value genetically modified oil crop having no risk of gene flow into feed and food crops.

Differentiation of two industrial oil sands process-affected waters by two-dimensional gas chromatography/mass spectrometry of diamondoid acid profiles.

RATIONALE: Processing of the oil sands of Canada has produced large amounts of process-affected water (OSPW). Concerns have been raised over the possible environmental impacts of any leakage of OSPW from storage lagoons which contain toxicants, including organic acids. Natural weathering of oil sands deposits may also produce the toxicants, including the acids. Therefore, there is a need for differentiation of the possible natural and industrial sources of such toxicants and also for methods suitable for monitoring changes in the composition of OSPW during long-term storage. METHODS: Here we show in a simple preliminary study of the two samples currently available to us, by use of comprehensive two-dimensional gas chromatography/time-of-flight mass spectrometry (GCxGC/ToF-MS), the distributions of methyl esters of individual isomeric diamondoid acids in OSPW from lagoons with different histories and from different industrial operators. RESULTS: We show that the distributions of methyl esters of individual isomeric diamondoid acids, including methyladamantane carboxylic and ethanoic acids, identified by comparison with data for reference compounds, can be differentiated readily. The use of acids with known structures, each verified by authentic acids, known toxicities and known and/or predictable physicochemical properties, to distinguish the different sources is advantageous, since factors likely to control the fate and dispersion of the acids can then more easily be predicted. It is postulated that the differences observed in the relative amounts of some of the acids result from variable extents of bacterial transformation of the organic matter in OSPW. CONCLUSIONS: The differences in distributions of diamondoid acids clearly vary between the two samples of OSPW and may prove very useful for monitoring the fate of different sources of OSPW both in storage and in the wider environment, once a wider collection of representative samples is available for study.

Oil mist and vapour concentrations from drilling fluids: inter- and intra-laboratory comparison of chemical analyses.

OBJECTIVES: There are no recognized analytical methods for measuring oil mist and vapours arising from drilling fluids used in offshore petroleum drilling industry. To inform the future development of improved methods of analysis for oil mist and vapours this study assessed the inter- and intra-laboratory variability in oil mist and vapour analysis. In addition, sample losses during transportation and storage were assessed. METHODS: Replicate samples for oil mist and vapour were collected using the 37-mm Millipore closed cassette and charcoal tube assembly. Sampling was conducted in a simulated shale shaker room, similar to that found offshore for processing drilling fluids. Samples were analysed at two different laboratories, one in Norway and one in the UK. Oil mist samples were analysed using Fourier transform infrared spectroscopy (FTIR), while oil vapour samples were analysed by gas chromatography (GC). RESULTS: The comparison of replicate samples showed substantial within- and between-laboratory variability in reported oil mist concentrations. The variability in oil vapour results was considerably reduced compared to oil mist, provided that a common method of calibration and quantification was adopted. The study also showed that losses can occur during transportation and storage of samples. CONCLUSIONS: There is a need to develop a harmonized method for the quantification of oil mist on filter and oil vapour on charcoal supported by a suitable proficiency testing scheme for laboratories involved in the analysis of occupational hygiene samples for the petroleum industry. The uncertainties in oil mist and vapour measurement have substantial implications in relation to compliance with occupational exposure limits and also in the reliability of any exposure-response information reported in epidemiological studies.