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At least 55 records · Page 3Linked to original sources
PubMed2001

Unique case of fatal carbon monoxide poisoning in the absence of a combustible fossil fuel.

A 37-year-old man died as a result of exposure to carbon monoxide within an apartment. An investigation of the apartment showed no gas appliances or gas supply to the apartment and no evidence of any combustion event to any part of the apartment or roof space. Inhalation of dichloromethane was excluded. Heating to the apartment was found to be via an electrical storage heater, the examination of which revealed that the cast-iron core and insulating material showed evidence of heat damage with significant areas devoid of carbon. This electric storage heater is hypothesized to be the source of carbon for the fatal production of carbon monoxide within the apartment.

Adult↗
PubMed1986

Epidermal carcinogenesis studies of synthetic fossil fuel materials in mice.

Skin tumor response in mice to solvent fractions of heavy distillate (HD) from a solvent-refined coal (SRC-II) process indicated that the basic tar and neutral tar were the most carcinogenically potent fractions. Assays of another SRC-II coal liquid that had been fractionally distilled indicated that the carcinogenicity of this material for mouse skin is due to that portion boiling above 371 degrees C (700 degrees F), and that the carcinogenic potency of the material increased with boiling point. Samples of the 399-427 degrees C (750-800 degrees F) distillate were nitrosated to destroy primary aromatic amines and were chemically fractionated to assess the carcinogenicity of chemical class fractions of these complex mixtures. Data from these assays indicated that neutral polycyclic aromatic hydrocarbons (PAH) and nitrogen-containing polycyclic aromatic compounds (NPAC) both contribute to the carcinogenicity of this distillate.

Animals↗
PubMed1983

Metallic elements in fossil fuel combustion products: amounts and form of emissions and evaluation of carcinogenicity and mutagenicity.

Metallic elements contained in coal, oil and gasoline are mobilized by combustion processes and may be emitted into the atmosphere, mainly as components of submicron particles. The information about the amounts, composition and form of metal compounds is reviewed for some fuels and combustion processes. Since metal compounds are always contained in urban air pollutants, they have to be considered whenever an evaluation of biological impact of air pollutants is made. The value of currently used bioassays for the evaluation of the role of trace metal compounds, either as major biologically active components or as modifiers of biological effects of organic compounds is assessed. The whole animal bioassays for carcinogenicity do not seem to be an appropriate approach. They are costly, time-consuming and not easily amenable to the testing of complex mixtures. Some problems related to the application and interpretation of short-term bioassays are considered, and the usefulness of such bioassays for the evaluation of trace metal components contained in complex air pollution mixtures is examined.

Air Pollutants↗
PubMed2000

Methane ice worms: Hesiocaeca methanicola colonizing fossil fuel reserves.

During a research cruise in July 1997 in the Gulf of Mexico we discovered a gas hydrate approximately 1 m thick and over 2 m in diameter which had recently breached the sea floor at a depth of 540 m. The hydrate surface visible from the submarine was considerably greater than that of any other reported hydrate. Two distinct color bands of hydrate were present in the same mound, and the entire exposed surface of the hydrate was infested (2500 individuals/m2) with 2 to 4 cm-long worms, since described as a new species, Hesiocaeca methanicola, in the polychaete family Hesionidae (Desbruyères and Toulmond 1998). H. methanicola tissue stable isotope values are consistent with a chemo-autotrophic food source. No evidence of chemo-autotrophic symbionts was detected, but geochemical data support the presence of abundant free living bacteria on the hydrate. The activities of the polychaetes, grazing on the hydrate bacteria and supplying oxygen to their habitats, appears to contribute to the dissolution of hydrates in surface sediments.

Animals↗
PubMed1996

Molecular mechanisms of biocatalytic desulfurization of fossil fuels.

The development of biocatalytic desulfurization of petroleum fractions may allow its use in place of conventional hydrodesulfurization (HDS). Dibenzothiophene (DBT) is representative of a broad range of sulfur heterocycles found in petroleum that are recalcitrant to desulfurization via HDS. Rhodococcus sp. strain IGTS8 has the ability to convert DBT to 2-hydroxybiphenyl (HBP) with the release of inorganic sulfur. The conversion of DBT to HBP is catalyzed by a multienzyme pathway consisting of two monooxygenases and a desulfinase. The final reaction catalyzed by the desulfinase appears to be the rate limiting step in the pathway. Each of the enzymes has been purified to homogeneity and their kinetic and physical properties studied. Neither monooxygenase has a tightly bound cofactor and each requires an NADH-FMN oxidoreductase for activity. An NADH-FMN oxidoreductase has been purified from Rhodococcus and is a protein of approximately 25,000 molecular weight with no apparent sequence homology to any other protein in the databases. We describe a unique sulfur acquisition system that Rhodococcus uses to obtain sulfur from very stable heterocyclic molecules.

Biodegradation, Environmental↗
PubMed1981

Comparison of the mutagenicities of fossil fuels.

Chemical fractions from 4 shale oils including one produced in an above-ground retort (Paraho), 2 produced below ground by in situ method (Occidental and Geokinetics), and 1 produced by a simulated modified in situ process (Livermore), were tested for mutagenicity against Salmonella typhimurium TA98 in the Ames assay system. Their mutagenic activities were compared with 2 other complex materials: a high-boiling coal distillate (The Solvent Refined Coal Process I (SRC II) heavy distillate), and a crude petroleum (Prudhoe Bay). Each material was fractionated by Sephadex LH-20 partition chromatography and by acid-base solvent extraction to provide chemical fractions for bioassay. Mutagenic activity was detected in the coal liquid (and their fractions), but not in the natural crude oil nor in any of its fractions. The basic and tar fractions derived by solvent extraction, and the LH-20 methanol fractions contained most of the mutagenic activity recovered from the unfractionated material. The heavy distillate was approx. 10 times more active in the Ames assay than the most mutagenically active shale oil. The most mutagenically active of the shale oils was about 10 times more active than the least active shale oil.

Fossil Fuels↗
PubMed2002

Fossil fuel and wood combustion as recorded by carbon particles in Lake Erie sediments 1850-1998.

Carbon particle analysis was performed on a dated sediment core from Lake Erie in order to explore the inputs of pollution from incomplete combustion of coal, oil, and wood. Carbon particles were isolated from the sediment by chemical digestion, and elemental carbon content was determined by CHN analysis. The type of carbon particle (from burning coal, oil, and wood) and particle size and relative abundance were determined using scanning electron microscopy on 100 particles from each core section. The elemental carbon content in the Lake Erie core ranges from 2.5 to 7.4 mg of carbon/g of sediment (1850-1998), and the maximum carbon content in the sediment occurs in the late 1960s to early 1970s. It is shown that particle mass is a better predictor than particle number of historical energy consumption records. This is especially clear for wood where variable particle volumes play a significant role in determining the record of elemental carbon mass from wood burning. Lake Erie core's content of total carbon and carbon particle type is in agreement with U.S. energy consumption records, except that a wood maximum occurs during 1905-1917, about 36 yr after the U.S. consumption maximum from 1870 to 1880.

Air Pollutants↗
PubMed2006

Dispersion modeling of polycyclic aromatic hydrocarbons from combustion of biomass and fossil fuels and production of coke in Tianjin, China.

A USEPA, procedure, ISCLT3 (Industrial Source Complex Long-Term), was applied to model the spatial distribution of polycyclic aromatic hydrocarbons (PAHs) emitted from various sources including coal, petroleum, natural gas, and biomass into the atmosphere of Tianjin, China. Benzo[a]pyrene equivalent concentrations (BaPeq) were calculated for risk assessment. Model results were provisionally validated for concentrations and profiles based on the observed data at two monitoring stations. The dominant emission sources in the area were domestic coal combustion, coke production, and biomass burning. Mainly because of the difference in the emission heights, the contributions of various sources to the average concentrations at receptors differ from proportions emitted. The shares of domestic coal increased from approximately 43% at the sources to 56% at the receptors, while the contributions of coking industry decreased from approximately 23% at the sources to 7% at the receptors. The spatial distributions of gaseous and particulate PAHs were similar, with higher concentrations occurring within urban districts because of domestic coal combustion. With relatively smaller contributions, the other minor sources had limited influences on the overall spatial distribution. The calculated average BaPeq value in air was 2.54 +/- 2.87 ng/m3 on an annual basis. Although only 2.3% of the area in Tianjin exceeded the national standard of 10 ng/m3, 41% of the entire population lives within this area.

Air Movements↗
PubMed2006

Community mercury levels in the vicinity of peri-urban waste disposal sites and fossil fuel burning operations.

INTRODUCTION: A study was conducted as a result of concern about mercury absorption amongst residents of a peri-urban area in Cape Town, South Africa, in close proximity to waste disposal sites and an industrial area. STUDY METHODS: The study compared urine mercury concentrations in a random sample of adult residents and children in both the formal and informal housing settlements of the "exposure" area (n = 90) and a control area (n = 90). A short questionnaire elicited demographic, lifestyle and medical details and possible occupational, household and environmental mercury exposures. RESULTS: The two samples were comparable with respect to background and potential confounding variables. The prevalence of urinary mercury levels>or=the WHO reference range in the exposure area was also higher than that in the control area (13% vs. 0%). The median urinary mercury concentrations in both study areas were below the World Health Organisation (WHO) reference level of 5.0 microg/g creatinine. The median level in the exposure area was slightly, but statistically significantly, higher than in the control area (1.1 vs. 0.25 microg/g creatinine), and the excess persisted after controlling for known possible mercury exposures. CONCLUSIONS: This is to our knowledge the first study of community inorganic mercury absorption in a developing country setting, and where airborne mercury was the exposure of concern. It was concluded that the health risk associated with the urinary mercury levels of residents in the exposure area was very low. However, low level environmental exposure in the area of concern could not be excluded.

Adolescent↗
PubMed1998

Use of 13C nuclear magnetic resonance to assess fossil fuel biodegradation: fate of [1-13C]acenaphthene in creosote polycyclic aromatic compound mixtures degraded by bacteria.

[1-13C]acenaphthene, a tracer compound with a nuclear magnetic resonance (NMR)-active nucleus at the C-1 position, has been employed in conjunction with a standard broad-band-decoupled 13C-NMR spectroscopy technique to study the biodegradation of acenaphthene by various bacterial cultures degrading aromatic hydrocarbons of creosote. Site-specific labeling at the benzylic position of acenaphthene allows 13C-NMR detection of chemical changes due to initial oxidations catalyzed by bacterial enzymes of aromatic hydrocarbon catabolism. Biodegradation of [1-13C]acenaphthene in the presence of naphthalene or creosote polycyclic aromatic compounds (PACs) was examined with an undefined mixed bacterial culture (established by enrichment on creosote PACs) and with isolates of individual naphthalene- and phenanthrene-degrading strains from this culture. From 13C-NMR spectra of extractable materials obtained in time course biodegradation experiments under optimized conditions, a number of signals were assigned to accumulated products such as 1-acenaphthenol, 1-acenaphthenone, acenaphthene-1,2-diol and naphthalene 1,8-dicarboxylic acid, formed by benzylic oxidation of acenaphthene and subsequent reactions. Limited degradation of acenaphthene could be attributed to its oxidation by naphthalene 1,2-dioxygenase or related dioxygenases, indicative of certain limitations of the undefined mixed culture with respect to acenaphthene catabolism. Coinoculation of the mixed culture with cells of acenaphthene-grown strain Pseudomonas sp. strain A2279 mitigated the accumulation of partial transformation products and resulted in more complete degradation of acenaphthene. This study demonstrates the value of the stable isotope labeling approach and its ability to reveal incomplete mineralization even when as little as 2 to 3% of the substrate is incompletely oxidized, yielding products of partial transformation. The approach outlined may prove useful in assessing bioremediation performance.

Acenaphthenes↗