Assessment of hydrocarbon emissions from diesel invert mud residues treated in a bioreactor

Hydrocarbon emissions from a diesel invert mud residue (DIMR) were monitored while the hydrocarbons were being biodegraded in a solid‐phase bioreactor. Five to twenty percent of the reduction in diesel hydrocarbons was attributed to evaporation depending on the treatment, i.e. homogenization, cultivation, and aeration. Most of these volatile hydrocarbons were linear C₈ — C₁₂ alkanes and one‐ring aromatics. Of the treatments aeration had the largest effect on emissions; forced air through the bottom of the bioreactor cells increased emissions by three times over that of the non‐aerated cells. Cultivation increased hydrocarbon emission concentration as much as twofold over the pre‐cultivation value, however, emissions returned to the original levels within 12 hours. Homogenization had the least effect of all treatments. Diurnally, the emission rate was 40% higher in late afternoon than at midnight; the cause of which was probably atmospheric fluctuations such as temperature and solar radiation. The effects of daily atmospheric fluctuations were empirically modeled and taken into account for determining the total volume of emissions.     

Polynuclear aromatic compounds in kerosene,diesel and unmodified sunflower oil and in respective engine exhaust particulate emissions

Polynuclear aromatic compounds (PAC) were characterized in diesel fuel, kerosene fuel and unmodified sunflower oil as well as in their respective engine exhaust particulates. Diesel fuel was found to contain high amounts of different PAC, up to a total concentration of 14,740?ppm, including carbazole and dibenzothiophene, which are known carcinogens. Kerosene fuel was also found to contain high amounts of different PAC, up to a total concentration of 10,930?ppm, consisting mainly of lower molecular weight (MW) naphthalene and its alkyl derivatives, but no PAC component peaks were detected in the unmodified sunflower oil. Engine exhaust particulates sampled from a modified one-cylinder diesel engine running on diesel, kerosene and unmodified sunflower oil, respectively, were found to contain significantly high concentrations of different PAC, including many of the carcinogenic ones, in the soluble organic fraction (SOF). PAC concentrations detected at the exhaust outlet indicated that most of the PAC that were present in diesel and kerosene fuels before the test runs got completely burnt out during combustion in the engine whereas some new ones were also formed. The difference between the character and composition of PAC present in the fuels and those emitted in the exhaust particulates indicated that exhaust PAC were predominantly combustion generated. High amounts of PAC, up to totals of 52,900 and 4830?µg?m^?3 of burnt fuel, in diesel and kerosene exhaust particulates, respectively, were detected in the dilution tunnel when the exhaust emissions were mixed with atmospheric air. Significant amounts of PAC were also emitted when the engine was run on unmodified sunflower oil with a total concentration of 17,070?µg?m^?3 of burnt fuel detected in the dilution tunnel. High proportions of the combustion-generated PAC determined when the engine was run on diesel, kerosene and unmodified sunflower, respectively, consisted of nitrogen-containing PAC (PANH) and sulphur-containing PAC (PASH).     

Chemical speciation and anthropogenic sources of ambient volatile organic compounds (VOCs) during summer in Beijing, 2004

Volatile organic compounds (VOCs) were measured at six sites in Beijing in August, 2004. Up to 148 VOC species, including C₃ to C₁₂ alkanes, C₃ to C₁₁ alkenes, C₆ to C₁₂ aromatics, and halogenated hydrocarbons, were quantified. Although the concentrations differed at the sites, the chemical compositions were similar, except for the Tongzhou site where aromatics were significantly high in the air. Based on the source profiles measured from previous studies, the source apportionment of ambient VOCs was preformed by deploying the chemical mass balance (CMB) model. The results show that urban VOCs are predominant from mobile source emissions, which contribute more than 50% of the VOCs (in mass concentrations) to ambient air at most sites. Other important sources are gasoline evaporation, painting, and solvents. The exception is at the Tongzhou site where vehicle exhaust, painting, and solvents have about equal contribution, around 35% of the ambient VOC concentration. As the receptor model is not valid for deriving the sources of reactive species, such as isoprene and 1,3-butadiene, other methodologies need to be further explored.     

Investigation of the sources of aliphatic hydrocarbons in the mussel Mytilus edulis from north sea oil production platforms by Capillary glc and CGCMS†

Aliphatic hydrocarbons isolated from mussels collected over a 20 month period from three North Sea Forties field oil production platforms have been examined by capillary gas chromatography and gas chromatography‐mass spectrometry.

The biological hydrocarbons consist predominantly (300–700 μh g^‐1 lipid) of C₃₁ and C₃₃ n‐alkenes with 2, 3 and 4 double bonds probably derived from a dietary intake of Emiliania huxleyi, a microscopic coccolithophorid alga. In some of the mussels C₁₈, C₂₀ and C₂₂ n‐alkanes are present in unusually high abundance compared to their odd carbon number homologues. Possible reasons for this distribution are discussed.

The concentrations of fossil fuel hydrocarbons (mainly unresolved complex mixtures) in the mussels ranged from 330 to 5,298 μg g^‐1 of lipid. No significant increase in values was detected two months after the start of discharge of treated Forties production water from the Forties D platform.

To determine the pollutant hydrocarbon sources, the sterane and terpane distributions of hydrocarbon fractions isolated from the mussels and from a number of fossil fuels, including Forties crude oil, were examined by mass fragmentography. The steranes in the mussels from the Forties C and D platforms contained higher proportions of regular 14α(H), 17α(H) components than Forties oil in which the steranes were mainly 13ß(H), 17α(H) diasteranes. In addition, the terpane distributions of the mussel fractions differed markedly from that of Forties crude oil, particularly in the relative abundance of diterpanes to triterpanes, which was higher in the mussel fractions than in the oil, and in the absence of 17α(H), 18α(H), 21ß(H)‐18, 30‐bisnorhopane, a known component of Forties crude. Furthermore, the ratio of C₂₉ to C₃₀ triterpanes was greater than unity in the mussels but much less than unity in the Forties oil. These data preclude Forties or other similar North Sea crudes as the major source of pollutant aliphatic hydrocarbons in the mussels. The relative concentrations and distributions of steranes and triterpanes suggest that the most likely source of pollutants is a Middle Eastern based oil derived either from rig activities, or from background pollution in the North Sea. The low concentration of ≥ C₂₇ steranes in the more polluted mussels (e.g. Forties B; UCM > 200 ppm dry wt.) suggests that gas oils used on the platforms may be the major source of petrogenic hydrocarbons in these samples.     

Planning for the monitoring of pollutants from non‐stationary combustion sources†

The most important constituents of traffic exhaust are carbon monoxide, nitrogen oxides, volatile organic compounds, polycyclic hydrocarbons and lead. Satisfactory analytical methods are available for measuring these compounds, but the required expenditure in their application to air pollution studies is quite different. Due to correlations between the concentrations of several exhaust components in road air conclusions regarding the expected level of some substances can be drawn by measurement of another emitted compound. But the selection of indicator compounds must be made under the aspect of the source‐specific relationship of emitted substances. The temporal and spatial distribution of air pollutants in street air is affected by traffic emissions more than by meteorological conditions. “Fingerprints”; of typical organic gaseous components of traffic exhaust also were found in residential areas.     

Investigating the potential for different scooter and car exhaust emissions to cause cytotoxic and (pro-)inflammatory responses to a 3D in vitro model of the human epithelial airway

The aim of this study was to compare the cytotoxicity and the (pro-)inflammatory responses of two-stroke (direct injection and carburetor technology) and four-stroke scooter and diesel car exhaust emissions on lung cells in vitro. This was analyzed by exposing a 3D in vitro model of the epithelial airway (consisting of human bronchial epithelial cells (cell line 16HBE14o^?) combined with human whole blood monocyte-derived macrophages and dendritic cells) to physically characterized exhaust emissions. Biological endpoints of cytotoxicity (lactate dehydrogenase release), as well as pro-inflammatory cytokine (tumor necrosis factor (TNF)-α) and inflammatory chemokine (interleukin(IL)-8) stimulation were examined. Two-stroke direct injection scooter exhaust contained the highest particle number concentration and nitrogen oxides (NO _x ) concentrations and the emissions from the two-stroke carburetor scooter contained the highest hydrocarbon and lowest NO _x concentrations. The four-stroke scooter emitted the highest carbon monoxide concentration whereas the cars emitted the lowest. The combination of various technical optimizations for the two-stroke direct injection scooter (particle filter, oxidative catalyst, better oil and fuel) reduced the total emissions strongly and the TNF-α concentration significantly (p?相似文献   

Emission factors of gaseous carbonaceous species from residential combustion of coal and crop residue briquettes

Experiments were performed to measure the emission factors (EFs) of gaseous carbonaceous species, such as CO₂, CO, CH₄, and non-methane volatile organic compounds (NMVOCs), from the combustion of five types of coal of varying organic maturity and two types of biomass briquettes under residential burning conditions. Samples were collected in stainless steel canisters and 2,4-dinitrophenylhydrazine (DNPH) cartridges and were analyzed by GC-FID/MS and HPLC, respectively. The EFs from crop residue briquette burning were generally higher than those from coals, with the exception of CO₂. The dominant NMVOC species identified in coal smoke were carbonyls (41.7%), followed by C2 unsaturated hydrocarbons (29.1%) and aromatics (12.1%), while C2 unsaturated hydrocarbons were the dominant species (68.9%) emitted from the combustion of crop residue briquettes, followed by aromatics (14.4%). A comparison of burning normal crop residues in stoves and the open field indicated that briquettes emitted a larger proportion of ethene and acetylene. Both combustion efficiency and coal organic maturity had a significant impact on NMVOC EFs from burning coal: NMVOC emissions increased with increasing coal organic maturity but decreased as the combustion efficiency improved. Emissions from the combustion of crop residue briquettes from stoves occurred mainly during the smoldering process, with low combustion efficiency. Therefore, an improved stove design to allow higher combustion efficiency would be beneficial for reducing emissions of carbonaceous air pollutants.     

PM2.5: global progress in controlling the motor vehicle contribution

It is well established that ambient particles in the size range of 2.5 microns or less case a wide variety of adverse health effects. According to a recent study from the World Health Organization, in 2010 these effects resulted in approximately 3.2million premature deaths with vehicles being one of the significant contributors. Diesel vehicle particulate emissions which are virtually all smaller than 2.5 microns raise additional special concerns due to their carcinogenicity and high ratio of black carbon （BC） to organic carbon; black carbon has recently been found to be the second most important contributor to climate change after carbon dioxide. Other pollutants emitted by diesels and other vehicles such as the oxides of nitrogen and volatile organic compounds also contribute to ambient particulate matter smaller than 2.5 microns in size （PM2.5） after undergoing secondary transformations in the atrno- sphere. Technologies have dramatically reduce vehicle been developed that can emissions when clean, low sulfur fuels are available and these technologies are being phased in throughout the industrialized world resulting in a global decrease in particulate matter （PM） and BC emissions from vehicles. However the vehicle population is growing rapidly in the developing world, leading to increases in emissions in many countries. Unless these rapidly industrializing countries move to state of the art vehicles and clean fuels, global PM, BC and NOx emissions from road vehicles will start to turn up over the next 10 to 15 years.     

Hydrocarbons in benthic algae from the eastern Gulf of Mexico

Thirty-six samples of benthic algae were collected from the continental shelf along the eastern Gulf of Mexico. The algae contain 82.8±143 ppm aliphatic hydrocarbons by dry weight and 11.8±22.7 ppm aromatic and polyolefinic hydrocarbons. The aliphatic constituents of red algae are composed almost entirely of n-C₁₇ (70 to 95% of aliphatic weight); green algae have varying amounts of n-alkanes in the range of n-C₁₅ to n-C₁₉, with homologous series of odd carbon number n-alkenes. Phytadienes occur as high as 740 ppm dry weight in the green algae and do not appear to be related to time or place of collection or to presence of any petroleum pollutants. The single brown algal species contains predominantly n-C₁₅. About 30% of the samples have hydrocarbons resembling degraded petroleum residues, but no petroleum pollution of recent origin was detected in any specimen.     

Organic composition in the dry season rainwater of Guangzhou, China

This paper reports the results from a study of the organic composition of rainwater collected at Tianhe district of Guangzhou city, P.R. China, during the dry season. Several special setups of a pyrex bottle with a glass funnel were used for the collection of the rainwater. Three fractions (aliphatics, PAHs and fatty acids) were separated from the total extracted organic compounds and identified with GC-MS. The molecular diagnostic ratios were utilized for the source reconciliation. The aliphatic hydrocarbon and the biomarkers (triterpanes and steranes) distribution show a characteristic of the petrochemical source in the rainwater samples. The PAHs diagnostic ratios [e.g. MP/P, MPI, Fl/ (Fl + Py)] indicated vehicular emissions. The fatty acids ratios (e.g. C_18:1/C_18:0 and C_18:2/C_18:0) reflect the contribution of cooking emissions, while the higher plant waxes play little part. Moreover, the values of MP/P, MPI, BaA/(BaA + CT) and BeP/(BeP + BaP) reflected the origin of the long-distance transportation to some extent. On the whole, for the dry season rainwater, all molecular diagnostic ratios indicated the complexity of the organic composition of the rain, which have the characteristics of both a local emission contribution and a long-distance transportation contribution.     

Very long-chain aliphatic hydrocarbons in lipids of mussels (Mytilus edulis) suspended in the water column near petroleum operations off Sable Island,Nova Scotia,Canada

Mussels (Mytilus edulis) suspended in the water column in 1994 and 1995 for the monitoring of oil drilling operations off Sable Island, Nova Scotia were examined for hydrocarbon profiles, particularly aliphatic hydrocarbons. A spring bloom of phytoplankton occurred during the 90-d suspension period in 1995. Hydrocarbons isolated from the 1995 suspended mussels showed very high concentrations of both biogenic hydrocarbons and very long-chain n-alkanes from C₂₀ to C₃₂, initially thought to be petrogenic. Both types of hydrocarbons were either not detected or were only present in trace amounts in the mussels suspended in 1994 at similar sites. The biogenic hydrocarbons in the 1995 mussels were apparently of planktonic origin, from the spring bloom, and were dominated by heneicosahexaene (21:6), followed by pristance, heptadecane, and varions monounsaturated and polyunsaturated phytenes, heptadecenes, nonadecenes and heneicosenes. They could be readily hydrogenated to yield the basic alkanes. The 1995 mussels suspended within 1 km from the oil well platform were probably slightly tainted by petrogenic hydrocarbons, as evidenced by the detection of phytane and high concentrations of total aliphatic hydrocarbons, whereas the mussels suspended 10 km from the platform showed only high concentrations of biogenic hydrocarbons and the novel long-chain n-alkanes. The occurrence of an unusual phytoplankton bloom during the suspension period severely interfered with the petroleum monitoring role of mussels by altering the mussel hydrocrbon profiles through the accumulation into and probably selective depuration of xenobiotic hydrocarbons from the mussel, tissues.J. Parsons (deceased)     

Stimulation and inhibition of phytoplankton growth by low molecular weight hydrocarbons

Experiments on 4 phylogenetically different phytoplankton exposed in culture to a range of concentrations of benzene, toluene and xylene showed a variety of growth responses for marine microalgae. The degree of influence of these aromatic hydrocarbons, all components of fuel oils and crude oils, varied with concentration, compound and species. Stimulation of growth in Dunaliella tertiolecta resulted from low μg/l concentrations of all three compounds, Skeletonema costatum showed no growth enhancement, while Cricosphaera carterae and Amphidinium carterae were intermediate in their reactions. Closed culture vessels were found to be necessary to retain these volatile hydrocarbons. Many of the previous laboratory studies on oil using standard methods — cotton plugs, screw caps or beakers — have overlooked the important influence of the volatile fraction. The species-specific stimulation of low concentrations was further shown in experiments with mixtures of No. 2 fuel oil. The volatile fraction was most biologically reactive, being the source of growth enhancement at low levels and a major growth inhibitor at high concentrations. Thus, a significant environmental effect of oil on marine primary production could be the growth stimulation of particular species by low molecular weight aromatic compounds resulting in an alteration of the natural phytoplankton community structure and its trophic relationships.     

Form-specific fragances fromOphrys insectifera L. (Orchidaceae) attract species of different pollinator genera. Evidence of sympatric speciation?

Two closely related forms ofOphrys insectifera were observed in the field to attract different pollinator species selectively.O. i. ssp.insectifera attracted males of two species ofArgogorytes (Sphecidae, Hymenoptera Aculeata) andO. i. ssp.aymoninii attractedAndrena combinata males (Andrenidae, Apoidea, Hymenoptera Aculeata). A third form,O. aff.i. ssp.insectifera, attracted none of these three species. Volatile compounds from flowers and inflorescences of the three forms (originating from Öland, Sweden, and Aveyron, France) were collected, using entrainment, enfleurage, and solvent extraction techniques, and identified by gas chromatography — mass spectrometry. Scent differences between the three forms were confirmed in the amounts of aliphatic hydrocarbons (C₁₁–C₁₉), methyl esters (C₁₄–C₁₈), short chain aliphatic 1-alcohols (C₆–C₁₂), and monoterpene alcohols (C₁₀).     

Biogeochemistry of aromatic hydrocarbons in the benthos of microcosms†

Investigations into the fate of petroleum compounds in the marine environment were carried out using experimental microcosms of two sizes and designs. Aromatic hydrocarbons or No. 2 fuel oil were spiked to the water of a 13 m³ continuous flow system and to a 2281 recycled flow system. The transport and alteration of this oil was traced in the sediment and benthic organisms (Glycera americana, Crepidula sp., and Nephtys incisa) of these microcosms. Measurable contamination was found in both sample types. The aromatic hydrocarbon distribution, including relative isomeric distribution (e.g., C₂‐phenanthrenes) was found to be different in sediment and in organisms from that which was originally introduced to the experimental microcosm. Differences in isomer distribution between Glycera and Crepidula were also detected. Based on the experimental data: molecular weight and specific isomeric form, biochemical processes, solubility, and particle adsorption/desorption influence the fate of petroleum compounds in benthic ecosystems.     

Dependency of polycyclic aromatic hydrocarbon concentrations on particle size distribution in Tehran atmosphere

In this work, the airborne particulate matter with an aerodynamic diameter less than 10 µm (PM₁₀) was fractionated in a six-stage high-volume cascade impactor to identify particulate size distribution in Tehran atmosphere. The study was conducted at 15 sites located in the north, south, east, west, and central parts of Tehran in 2005. Air samples were analyzed for 16 polycyclic aromatic hydrocarbons (PAHs) by HPLC. The daily PM₁₀ concentrations at the peak of traffic in roadside areas were found to be 106–560 µg m^?3. The cumulated concentration sum of PAHs, based on 16 species, was found to have an average concentration of 380 ng m^?3. Furthermore, it was found that more than 60% of PAHs belonged to the small particulate size range, having sizes of less than 0.49 µm, some containing benzo(ghi)perylene and indeno(123cd)pyrene (high molecular weight) with average concentrations of 8 and 6 ng m^?3 and fluorene, phenanthrene, and fluoranthene (low molecular weight) with average concentrations of 14, 13, and 19 ng m^?3, respectively. In addition, the results revealed that the lighter three- and four-ring PAH compounds were the most abundant pollutants in the air collected at all the sampling sites.     

Air quality and micro-meterological monitoring of gaseous pollutants/flame emissions from burning crude petroleum in poultry house

Air quality of gaseous emissions from crude petroleum flames and fumes were monitored in a poultry house at 10 min intervals; from 10.10am–11.10am daily for 14 days. The crude petroleum burning was simulated in a metal burner, 22.86 cm high with a diameter of 17.80 cm and a thickness of 1.27 cm designed for the purpose. The micro-climate (ambient temperature, relative humidity and light intensity) of the experimental environment (poultry houses) was recorded. Results showed that the mean gaseous pollutants emitted before and during the experiments varied within the poultry house. Gases such as sulphur dioxide (SO₂), hydrogen sulphide (H₂S), methane(CH₄) and carbon monoxide (CO) were higher in the brooding than finishing phase, while volatile organic carbon (VOC) and suspended particulate matter (SPM) levels were lower at the brooding than finishing phase. The values obtained in this study for 60 min (at 10 min intervals) are far higher than the values elucidated by the Federal Environmental Protection Agency, which are outdoor air quality measurements as compared to those in this study measured indoors.     

High seasonal variation of atmospheric C and particle concentrations in Delhi,India

The highly populated Indian regions are currently in a phase of rapid economic growth resulting in high emissions of carbonaceous aerosols. This leads to poor air quality and impact on climate. The chemical composition of carbonaceous aerosols has rarely been studied in industrial areas of India. Here, we investigated carbonaceous aerosols in particulate matter (PM) monthly in the industrial area of Delhi in 2011. The concentrations of organic C and elemental C in PM₁₀ fraction were analyzed. Results show a clear seasonal variability of organic and elemental C. PM₁₀ ranged 95.9–453.5 μg m^?3, organic C ranged 28.8–159.4 μg m^?3, and elemental C ranged 7.5–44.0 μg m^?3; those values were higher than reported values. Organic and elemental C were correlated with each other in pre-monsoon and winter seasons, implying the existence of similar emission sources such as coal combustion, biomass burning and vehicular exhaust. The annual average contribution of total carbonaceous aerosols in PM₁₀ was estimated as 62 %.     

Impact of gasoline engine deposits on light duty vehicle emissions: in-use case study in Beijing, China

Tailpipe emissions from light-duty gasoline vehicles usually deteriorate over time. The accumulation of engine deposits due to inadequate gasoline detergency is considered to be one of the major causes of such emission deterioration. Six in-use light-duty gasoline vehicles in Beijing were tested to investigate the impact of engine deposits on emissions of hydrocarbons (HC), carbon monoxide (CO) and nitrogen oxides (NO _x ). Emissions under cold start and hot running test conditions from the six light duty vehicles were measured before and after engine deposits were removed. Results show that although individual vehicles reacted differently for each of the pollutants, elimination of engine deposits on average reduced HC emissions under hot running conditions by 29.4%, CO emissions under cold start conditions by 23.0% and CO emissions under hot running conditions by 35.5% (t < 0.05 in all cases). No pollutant emissions increased with statistical significance (t < 0.05) after the removal of engine deposits. Variations of emission changes upon removal of engine deposits were observed. Such variations are in line with previous studies, implying that the impact patterns of engine deposits on vehicle emissions may be subject to many influencing factors that are not fully understood and difficult to control under all conditions. A statistical view of the impact of engine deposits on vehicle emissions may be appropriate for evaluation of emissions reductions across a city or a country. It is necessary to maintain sufficient and effective gasoline fuel detergency in practice to keep the engines clean and in turn reduce vehicle emissions.     

Impacts of methanol fuel on vehicular emissions: A review

● Methanol effectively reduces CO, HC, CO₂, PM, and PN emissions of gasoline vehicles. ● Elemental composition of methanol directly affects the reduction of emissions. ● Several physicochemical properties of methanol help reduce vehicle emissions. The transport sector is a significant energy consumer and a major contributor to urban air pollution. At present, the substitution of cleaner fuel is one feasible way to deal with the growing energy demand and environmental pollution. Methanol has been recognized as a good alternative to gasoline due to its good combustion performance. In the past decades, many studies have investigated exhaust emissions using methanol-gasoline blends. However, the conclusions derived from different studies vary significantly, and the explanations for the effects of methanol blending on exhaust emissions are also inconsistent. This review summarizes the characteristics of CO, HC, NO_x, CO₂, and particulate emissions from methanol-gasoline blended fuels and pure methanol fuel. CO, HC, CO₂, particle mass (PM), and particle number (PN) emissions decrease when methanol-blended fuel is used in place of gasoline fuel. NO_x emission either decreases or increases depending on the test conditions, i.e., methanol content. Furthermore, this review synthesizes the mechanisms by which methanol-blended fuel influences pollutant emissions. This review provides insight into the pollutant emissions from methanol-blended fuel, which will aid policymakers in making energy strategy decisions that take urban air pollution, climate change, and energy security into account.     

Chemical characteristics of fine particulate matter emitted from commercial cooking

The chemical characteristics of fine particulate matter (PM_2.5) emitted from commercial cooking were explored in this study. Three typical commercial restaurants in Shanghai, i.e., a Shanghai-style one (SHS), a Sichuan-style one (SCS) and an Italian-style one (ITS), were selected to conduct PM_2.5 sampling. Particulate organic matter (POM) was found to be the predominant contributor to cooking-related PM_2.5 mass in all the tested restaurants, with a proportion of 69.1% to 77.1%. Specifically, 80 trace organic compounds were identified and quantified by gas chromatography/mass spectrometry (GC/MS), which accounted for 3.8%–6.5% of the total PM_2.5 mass. Among the quantified organic compounds, unsaturated fatty acids had the highest concentration, followed by saturated fatty acids. Comparatively, the impacts of other kinds of organic compounds were much smaller. Oleic acid was the most abundant single species in both SCS and ITS. However, in the case of SHS, linoleic acid was the richest one. ITS produced a much larger mass fraction of most organic species in POM than the two Chinese cooking styles except for monosaccharide anhydrides and sterols. The results of this study could be utilized to explore the contribution of cooking emissions to PM_2.5 pollution and to develop the emission inventory of PM_2.5 from cooking, which could then help the policymakers design efficient treatment measures and control strategies on cooking emissions in the future.