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1.
Aarif H. El-Mubarak Ahmed I. Rushdi Khalid F. Al-Mutlaq Abdulqader Y. Bazeyad Staci L. M. Simonich Bernd R. T. Simoneit 《Environmental science and pollution research international》2014,21(1):558-567
In an effort to assess the occurrence and sources of polycyclic aromatic hydrocarbons (PAHs) in the ambient air of Riyadh, Saudi Arabia, PM10 samples were collected during December 2010. Diagnostic PAH concentration ratios were used as a tool to identify and characterize the PAH sources. The results reflect high PM10 and PAH concentrations (particulate matter (PM)?=?270–1,270 μg/m3). The corresponding average PAH concentrations were in the range of 18?±?8 to 1,003?±?597 ng/m3 and the total concentrations (total PAHs (TPAHs) of 17 compounds) varied from 1,383 to 13,470 ng/m3 with an average of 5,871?±?2,830 ng/m3. The detection and quantification limits were 1–3 and 1–10 ng/ml, respectively, with a recovery range of 42–80 %. The ratio of the sum of the concentrations of the nine major non-alkylated compounds to the total (CPAHs/TPAHs) was 0.87?±?0.10, and other ratios were determined to apportion the PM sources. The PAHs found are characteristic for emissions from traffic with diesel being a predominant source. 相似文献
2.
Bernd R. T. Simoneit M. A. Mazurek T. A. Cahill 《Journal of the Air & Waste Management Association (1995)》2013,63(4):387-390
The atmosphere of the Lake Tahoe air basin is contaminated with high molecular weight (> C12) petroleum hydrocarbons. Aerosol samples were collected by high-volume filtration and the solvent-soluble organic matter was analyzed. The relative concentrations of petroleum residues found were as follows: winter > summer and day > night. This contamination is primarily due to the poorer combustion of diesel and home heating fuels at that altitude and during periods of colder climate. 相似文献
3.
An overview of the application of organic geochemistry to the analysis of organic matter on aerosol particles is presented
here. This organic matter is analyzed as solvent extractable bitumen/ lipids by gas chromatography-mass spectrometry. The
organic geochemical approach assesses the origin, the environmental history and the nature of secondary products of organic
matter by using the data derived from specific molecular analyses. Evaluations of production and fluxes, with cross-correlations
can thus be made by the application of the same separation and analytical procedures to samples from point source emissions
and the ambient atmosphere. This will be illustrated here with typical examples from the ambient atmosphere (aerosol particles)
and from emissions of biomass burning (smoke).
Organic matter in aerosols is derived from two major sources and is admixed depending on the geographic relief of the air
shed. These sources are biogenic detritus (e.g., plant wax, microbes, etc.) and anthropogenic particle emissions (e.g., oils,
soot, synthetics, etc.). Both biogenic detritus and some of the anthropogenic particle emissions contain organic materials
which have unique and distinguishable compound distribution patterns (C14-C40). Microbial and vascular plant lipids are the dominant biogenic residues and petroleum hydrocarbons, with lesser amounts
of the pyrogenic polynuclear aromatic hydrocarbons (PAH) and synthetics (e.g., chlorinated compounds), are the major anthropogenic
residues.
Biomass combustion is another important primary source of particles injected into the global atmosphere. It contributes many
trace substances which are reactants in atmospheric chemistry and soot paniculate matter with adsorbed biomarker compounds,
most of which are unknown chemical structures. The injection of natural product organic compounds into smoke occurs primarily
by direct volatilization/steam stripping and by thermal alteration based on combustion temperature. Although the molecular
composition of organic matter in smoke particles is highly variable, the molecular tracers are generally still source specific.
Retene has been utilized as a tracer for conifer smoke in urban aerosols, but is not always detectable. Dehydroabietic acid
is generally more concentrated in the atmosphere from the same emission sources. Degradation products from biopolymers (e.g.,
levoglucosan from cellulose) are also excellent tracers. An overview of the biomarker compositions of biomass smoke types
is presented here. Defining additional tracers of thermally-altered and directly-emitted natural products in smoke aids the
assessment of the organic matter type and input from biomass combustion to aerosols. The precursor to product approach of
compound characterization by organic geochemistry can be applied successfully to provide tracers for studying the chemistry
and dispersion of ambient aerosols and smoke plumes.
Presented at the 6th FECS Conference on Chemistry and the Environment, Atmospheric Chemistry and Air Pollution, August 26–28,
1998, Copenhagen. 相似文献
4.
Jeon SJ Meuzelaar HL Sheya SA Lighty JS Jarman WM Kasteler C Sarofim AF Simoneit BR 《Journal of the Air & Waste Management Association (1995)》2001,51(5):766-784
For a recent exploratory study of particulate matter (PM) compositions, origins, and impacts in the El Paso/Juarez (Paso del Norte) airshed, the authors relied on solvent extraction (SX)-gas chromatography/mass spectrometry (GC/MS) procedures to characterize 24-hr quartz fiber (QF) filter samples obtained from nine spatially distributed high-volume (Hi-Vol) PM10 samplers as well as on thermal desorption (TD)-GC/MS methods to characterize 45 time-resolved (2-hr) filter samples obtained with modified 1-m3/hr PM10 samplers. Principal component analysis and related chemometric techniques were used for data reduction and data fusion as well as for multiway data correlation. A high degree of correspondence (R2 = 0.821) was found between the rapid TD-GC/MS method (which can be carried out on 2-hr filter slices containing only microgram amounts of sample) and conventional SX-GC/MS procedures. The four main source patterns of organic PM components observed in GC/MS profiles of both temporally and spatially resolved receptor samples obtained in the El Paso/Juarez border airshed during the study period are interpreted to represent (1) vehicular emissions plus resuspended urban dust; (2) biomass combustion; (3) native vegetation detritus and resuspended agricultural dust; and (4) waste burning. Moreover, principal component analysis of combined, variance-weighted, temporally resolved TD-GC/MS data and spatially resolved SX-GC/MS data was used to determine approximate source locations for specific PM components identified in time-resolved receptor sample profiles. The same approach can be used to determine approximate circadian concentration profiles of specific PM components identified in spatially resolved receptor sample profiles. 相似文献
5.
Biomass burning as the main source of organic aerosol particulate matter in Malaysia during haze episodes 总被引:7,自引:0,他引:7
The haze episodes that occurred in Malaysia in September-October 1991, August-October 1994 and September-October 1997 have been attributed to suspended smoke particulate matter from biomass burning in southern Sumatra and Kalimantan, Indonesia. In the present study, polar organic compounds in aerosol particulate matter from Malaysia are converted to their trimethylsilyl derivatives and analyzed by gas chromatography-mass spectrometry in order to better assess the contribution of the biomass burning component during the haze episodes. On the basis of this analysis, levoglucosan was found to be the most abundant organic compound detected in almost all samples. The monosaccharides, alpha- and beta-mannose, the lignin breakdown products, vanillic and syringic acids and the minor steroids, cholesterol and beta-sitosterol were also present in some samples. The presence of the tracers from smoke overwhelmed the typical signatures of emissions from traffic and other anthropogenic activities in the urban areas. 相似文献
6.
Distributions and sources of polycyclic aromatic hydrocarbons in surface sediments from the Cross River estuary,S.E. Niger Delta,Nigeria 总被引:1,自引:0,他引:1
Ekpo BO Oyo-Ita OE Oros DR Simoneit BR 《Environmental monitoring and assessment》2012,184(2):1037-1047
Polycyclic aromatic hydrocarbon (PAH) analyses of surface sediments from the Cross River estuary by gas chromatography–mass
spectrometry indicated natural diagenetically derived PAHs in the upper estuary, with minor and variable amounts of petrogenic
and combustion-derived PAHs from human activities (lower estuary). The occurrence of significant amounts of perylene (average
23% of all PAHs) with the diagenetic natural PAHs in the middle estuary bordered by mangrove forests supports its origin from
terrestrial organic matter. The natural PAHs represent the highest percentage (average 76%) of the total PAHs in this tropical
environment. The traditional geochemical parameters, including the petrogenic PAHs, confirmed trace petroleum contamination
in the estuary. Specific PAH ratios such as Fl/Py and Fl/(Fl+Py) also support this source contribution. 相似文献
7.
Biomarkers are widely known to occur in the fossil record, but the unaltered biomolecules are rarely reported from sediments
older than Paleogene. Polar terpenoids, the natural products most resistant to degradation processes, were reported mainly
from the Tertiary conifers, and the oldest known are Cretaceous in age. In this paper, we report the occurrence of relatively
high concentrations of ferruginol derivatives and other polar diterpenoids, as well as their diagenetic products, in a conifer
wood Protopodocarpoxylon from the Middle Jurassic of Poland. Thus, the natural product terpenoids reported in this paper are definitely the oldest
polar biomolecules detected in geological samples. The extracted phenolic abietanes like ferruginol and its derivatives (6,7-dehydroferruginol,
sugiol, 11,14-dioxopisiferic acid) are produced only by distinct conifer families (Cupressaceae s. l., Podocarpaceae and Araucariaceae),
to which Protopodocarpoxylon could belong based on anatomical characteristics. Therefore, the natural product terpenoids are of great advantage in systematics
of fossil plant remains older than Paleogene and lacking suitable anatomical preservation. 相似文献
8.
Pang Swee Yun Suratman Suhaimi Latif Mohd Talib Khan Md Firoz Simoneit Bernd R. T. Mohd Tahir Norhayati 《Environmental science and pollution research international》2022,29(11):15849-15862
Environmental Science and Pollution Research - Surface sediments along the Southern Terengganu coast (≤7 km from the coast) were analyzed for polycyclic aromatic hydrocarbons (PAHs). The... 相似文献
9.
The relationship among sugar concentrations, microbial community and physical variables (precipitation and soil temperature) was investigated in a ryegrass soil from January 2004 to January 2005. Mono- and disaccharide sugars were extracted using a mixture of dichloromethane and methanol and analyzed as their TMS derivatives by GC-MS. Changes in microbial community were assessed using phospholipid and neutral lipid fatty acids (PLFA and NLFA, respectively) analysis. The results of a one-year study showed that the seasonal variability of sugar contents found in the soil samples is mainly related to biomass or nutritional status of the fungal community. The increase in sucrose and fructose exudation by plant roots in the beginning of the growing season (early spring) may be responsible for the highest fungal biomass amount (PLFAs) observed in this study. Fungal storage lipid abundances (NLFAs) peaked in summer, during the same period that the highest concentrations of mannitol and trehalose were detected. This is consistent with these two sugars being stress-induced fungal metabolites, produced due to the low soil moisture observed during this season. In contrast, bacterial community growth seems to be more dependent on plant substrate than on physical variables, since the strongest decrease in bacterial biomass amounts (PLFAs) was found after cutting of the ryegrass field in early July. 相似文献
10.
Daniele Fabbri Cristian Torri Bernd R.T. Simoneit Leszek Marynowski Ahmed I. Rushdi Monika J. Fabiańska 《Atmospheric environment (Oxford, England : 1994)》2009,43(14):2286-2295
Levoglucosan (L), mannosan (M), galactosan (G) and other cellulose and lignin markers from burn tests of Miocene lignites of Poland were determined by gas chromatography–mass spectrometry (GC–MS) to assess their distributions and concentrations in the smoke. Their distributions were compared to those in the pyrolysis products of the lignites. Levoglucosan and other anhydrosaccharides are products from the thermal degradation of cellulose and hemicellulose and are commonly used as tracers for wood smoke in the atmosphere. Here we report emission factors of levoglucosan in smoke particulate matter from burning of lignite varying from 713 to 2154 mg kg?1, which are similar to those from burning of extant plant biomass. Solvent extracts of the lignites revealed trace concentrations of native levoglucosan (0.52–3.7 mg kg?1), while pyrolysis yielded much higher levels (1.6–3.5 × 104 mg kg?1), indicating that essentially all levoglucosan in particulate matter of lignite smoke is derived from cellulose degradation. The results demonstrate that burning of lignites is an additional input of levoglucosan to the atmosphere in regions where brown coal is utilized as a domestic fuel. Interestingly, galactosan, another tracer from biomass burning, is not emitted in lignite smoke and mannosan is emitted at relatively low concentrations, ranging from 7.8 to 70.5 mg kg?1. Thus, we propose L/M and L/(M + G) ratios as discriminators between products from combustion of lignites and extant biomass. In addition, other compounds, such as shonanin, belonging to lignans, and some saccharides, e.g., α- and β-glucose and cellobiose, are reported for the first time in extracts of bulk lignites and of smoke particulate matter from burning these lignites. 相似文献