Article

Seasonal size-segregated PM10 and PAH concentrations in a rural area of sugarcane agriculture versus a coastal urban area in Southeastern Florida, USA

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Abstract

Airborne particulate matter (PM) is of health and environmental concern not only in highly urbanized areas, but also in rural areas that are used for intensive agricultural purposes. In this study, PM size-segregated samples were collected simultaneously for 12 months in a small town (Belle Glade, Florida), which is the center of a vast sugarcane growing area and at Delray Beach, a coastal city in Palm Beach County, Florida. During the winter sampling period, when sugarcane foliage is burned just before harvesting to reduce the amount of plant matter to be handled, PM10 levels were 50% or higher than otherwise measured, indicating that sugarcane harvesting and processing is a major local source for PM10. For the rest of the year, PM10 levels at both sites are similar, suggesting that ambient PM levels at both sites are impacted by the major urban centers in Southern Florida. During late July and early August, the PM10 levels at both sites were substantially elevated and revealed the typical red-brownish color of Saharan dust. This has been reported to occur frequently with suitable meteorological conditions over the Atlantic Ocean coupled with a Sahara dust storm event. During the sugarcane harvesting season at Belle Glade, the concentrations of PAHs associated with PM10 were up to 15 times higher than those measured during the summer growing season, indicating a substantially higher exposure of the rural population to these often mutagenic and carcinogenic compounds.

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... The present study observed that the high concentration levels of Phe, Flu and Pyr were recorded at LT and three to four times greater than that of other locations. Higher factor loading of BaP, Chr and BbF is a good factor for wood and coal combustion from stationary emission sources (Sevimoglua and Rogge 2016). For LT, remarkable elevations were recorded in the concentration level of Chr and BaP among the PAHs which were three to eight times than SS, HS and DB. ...
... Higher concentration level of Chr, BaP and BbF may be the indicators of vehicular emission, paved/unpaved road emission sources. High concentration level of BaP at LT indicates the burning of wood and mine fire emissions on the earth's surface (Sevimoglua and Rogge 2016). ...
... So, it can be concluded that coal combustion, mine fire and its associated activities are the dominating source of particle-bound PAHs at JCF, Dhanbad City during the study period (2012)(2013). Pre-harvested burning of foliage and coal combustion can be the sources of PAHs in this area (Sevimoglua and Rogge 2016;Zhang et al. 2017). Moreover, diesel, gasoline and fueled vehicles along with natural gas combustions can be another source of PAHs (Hazarika et al. 2017). ...
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... In rural areas, burning of biomass is a regular part of agricultural practices, including burning of grassland and crop residues. A few studies have determined these practices have a major impact on local ambient PAH concentrations (Noth et al., 2011;Sevimoglu and Rogge, 2016). On the other hand, very few studies have commented on the role that the use of heavy agricultural or grain drying machinery plays in rural PAH concentrations, even though agriculture has been reported as a major source of particulate matter PAHs in Europe (Lelieveld et al., 2015). ...
... The use of heavy machinery affects the emission levels and thus the PAH concentrations throughout the whole year as they generally are used continuously for different purposes during the year. Additionally, other agricultural practices, such as burning of biomass, contribute to the PAH emissions; burning of twigs, tree branches or stumps is a common practice in Finland just like in other countries (Afshar-Mohajer et al., 2016;Noth et al., 2011;Ravindra et al., 2008;Sevimoglu and Rogge, 2016). The use of wood for heating is also common in Finland. ...
... The use of wood as a main heating source can result in major emissions, and it can significantly worsen the local air quality. Many studies demonstrate well that atmospheric PAHs are dependent on seasons, precipitation, temperature as well as spatial factors, i.e. geography and topography, of sampling sites (Jedynska et al., 2014;Li et al., 2014b;Liu et al., 2014;Sevimoglu and Rogge, 2016;Viippola et al., 2016). The results of this 28-day study give a reasonable snapshot of amounts of PAHs in measured locations, but they do not allow definite conclusions to be drawn for the annual or average concentrations at any of the sampling sites. ...
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... Consequently, air masses moving in from the Atlantic over this highly populated coastline carry a wide range of urban pollutants further inland towards Lake Okeechobee, the agricultural land south of the Lake (sugarcane growing area) and even further into the Everglades National Park, Florida's West Coast and beyond, depending on wind direction. Occasionally, Saharan dust is carried into the study region (Sevimoglu & Rogge, 2016;Trapp, Millero, & Prospero, 2010). Because of the vicinity to the Atlantic Ocean, marine sea salt aerosol matter (Holmes & Miller, 2004;Pancras, Ondov, Poor, Landis, & Stevens, 2006) is carried with the airflow from the Atlantic Ocean into our study region. ...
... The size-segregated PM 10 information for the complete study year can be found in Sevimoglu and Rogge (2015) and details relating to the SBS and SGS and more organic compound compositional information is given in Sevimoglu and Rogge (2016). The monthly average concentrations of the 39 trace elements are reported in Table 1. ...
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To investigate the potential cancer risk resulting from biomass burning, polycyclic aromatic hydrocarbons (PAHs) bound to fine particles (PM2.5) were assessed in nine administrative northern provinces (NNP) of Thailand, before (N-I) and after (N-II) a haze episode. The average values of Σ3,4-ring PAHs and B[a]PEquivalent concentrations in world urban cities were significantly (p<0.05) much higher than those in samples collected from northern provinces during both sampling periods. Application of diagnostic binary ratios of PAHs underlined the predominant contribution of vehicular exhaust to PM2.5-bound PAH levels in NNP areas, even in the middle of the agricultural waste burning period. The proximity of N-I and N-II values in three-dimensional (3D) principal component analysis (PCA) plots also supports this conclusion. Although the excess cancer risk in NNP areas is much lower than those of other urban area and industrialized cities, there are nevertheless some concerns relating to adverse health impacts on preschool children due to non-dietary exposure to PAHs in home environments. Copyright © 2014 Elsevier B.V. All rights reserved.
Article
A sampling campaign was conducted to assess on-road particulate matter (PM) composition for three size fractions (PM10–2.5, PM2.5–0.25, and PM0.25) on three representative roadways in Los Angeles: 1) the I-110, a high-traffic freeway composed mostly of light-duty vehicles (LDVs), 2) the I-710, a major freeway for heavy-duty vehicles (HDVs) traveling to and from the Ports of Los Angeles and Long Beach, and 3) Wilshire/Sunset Blvd, two major surface streets. Concurrent sampling was conducted at the University of Southern California (USC), which was used as an urban background site. Two sets of PM samples were collected for each roadway, with a sampling duration of approximately 50 h for each set. The samples were analyzed for inorganic ions, elemental carbon (EC), organic carbon (OC), water-soluble OC (WSOC), and trace elements and metals. Results showed that the PM0.25 fraction is heavily influenced by on-road vehicular emissions, as indicated by average roadway PM concentrations that were 48.0 ± 9.4% higher than those observed at USC (p < 0.05), while the PM10–2.5 fraction is mostly influenced by resuspension of road dust and the PM2.5–0.25 fraction is mainly composed of secondary species. Overall, the composition of inorganic ions (%) was relatively consistent across the three roadway environments. With very low EC levels in PM10–2.5, the most notable difference among the three roadway environments was the PM2.5 EC levels observed on the I-710, which are 2.0 ± 0.2 μg m−3 and 4.1 times greater than USC, while levels on the I-110 and Wilshire/Sunset were 1.0 ± 0.2 μg m−3 and 0.6 ± 0.01 μg m−3 and 2.1 and 1.2 times greater, respectively. PM2.5 OC and WSOC concentrations were observed to be 1.6, 2.0, and 1.7 times greater on the I-110, I-710, and Wilshire/Sunset than corresponding levels at USC, respectively. Results from this study may have major public health implications for passengers who commute frequently on high-traffic roadways. Finally, a comparison of EC levels to previous studies conducted at fixed sites near the I-110 and I-710 showed substantial decreases in EC concentrations over the past years, which may be a result of the recent Port of Los Angeles Clean Truck Program.
Article
Anthropogenic semivolatile organic compounds (SOCs) that persist in the environment, bioaccumulate, are toxic at low concentrations, and undergo long-range atmospheric transport (LRT) were identified and quantified in the atmosphere of a Saharan dust source region (Mali) and during Saharan dust incursions at downwind sites in the eastern Caribbean (U.S. Virgin Islands, Trinidad and Tobago) and Cape Verde. More organochlorine and organophosphate pesticides (OCPPs), polycyclic aromatic hydrocarbons (PAHs), and polychlorinated biphenyl (PCB) congeners were detected in the Saharan dust region than at downwind sites. Seven of the 13 OCPPs detected occurred at all sites: chlordanes, chlorpyrifos, dacthal, dieldrin, endosulfans, hexachlorobenzene (HCB), and trifluralin. Total SOCs ranged from 1.9-126ng/m(3) (mean=25±34) at source and 0.05-0.71ng/m(3) (mean=0.24±0.18) at downwind sites during dust conditions. Most SOC concentrations were 1-3 orders of magnitude higher in source than downwind sites. A Saharan source was confirmed for sampled air masses at downwind sites based on dust particle elemental composition and rare earth ratios, atmospheric back trajectory models, and field observations. SOC concentrations were considerably below existing occupational and/or regulatory limits; however, few regulatory limits exist for these persistent organic compounds. Long-term effects of chronic exposure to low concentrations of SOCs are unknown, as are possible additive or synergistic effects of mixtures of SOCs, biologically active trace metals, and mineral dust particles transported together in Saharan dust air masses.
Article
Gasoline- and diesel-powered vehicles are known to contribute appreciable amounts of inhalable fine particulate matter to the atmosphere in urban areas. Internal combustion engines burning gasoline and diesel fuel contribute more than 21% of the primary fine particulate organic carbon emitted to the Los Angeles atmosphere. In the present study, particulate (d[sub p] [le] 2 [mu]m) exhaust emissions from six noncatalyst automobiles, seven catalyst-equipped automobiles, and two heavy-duty diesel trucks are examined by gas chromatography/mass spectrometry. The purposes of this study are as follows: (a) to search for conservative marker compounds suitable for tracing the presence of vehicular particulate exhaust emissions in the urban atmosphere, (b) to compile quantitative source profiles, and (c) to study the contributions of fine organic particulate vehicular exhaust to the Los Angeles atmosphere. More than 100 organic compounds are quantified, including n-alkanes, n-alkanoic acids, benzoic acids, benzaldehydes, PAH, oxy-PAH, steranes, pentacyclic triterpanes, azanaphthalenes, and others. Although fossil fuel markers such as steranes and pentacyclic triterpanes can be emitted from other sources, it can be shown that their ambient concentrations measured in the Los Angeles atmosphere are attributable mainly to vehicular exhaust emissions. 102 refs., 9 figs., 6 tabs.
Article
Meat cooking operations are a major source of organic aerosol emissions to the urban atmosphere, comprising up to 21% of the primary fine organic carbon particle emissions in the Los Angeles area. In the present study, the chemical composition of meat smoke aerosol is examined by high-resolution gas chromatography and gas chromatography/mass spectrometry. The objective is to search for molecular markers that will confirm the presence of meat smoke aerosol in urban atmospheric samples. More than 75 organic compounds are quantified, including the series of the n-alkanes, n-alkanoic acids, n-alkenoic acids, dicarboxylic acids, n-alkanals, n-alkenals, n-alkanones, n-alkanols, furans, lactones, amides, nitriles, polycyclic aromatic hydrocarbons, steroids, and pesticide residues. Prominent among the compounds emitted are n-hexadecanoic acid (i.e., palmitic acid), n-octadecanoic acid (i.e., stearic acid), cis-9-octadecenoic acid (i.e., oleic acid), nonanal, 2-octadecanal, 2-octadecanol, and cholesterol. Al-nanal, 2-octadecanal, 2-octadecanol, and cholesterol. Although cholesterol can be emitted from other sources, cholesterol concentrations measured in the West Los Angeles atmospheric aerosol are consistent with the cholesterol mass emission rates determined from meat cooking source tests.
Article
The major organic components of smoke particles from biomass burning are monosaccharide derivatives from the breakdown of cellulose, accompanied by generally lesser amounts of straight-chain, aliphatic and oxygenated compounds and terpenoids from vegetation waxes, resins/gums, and other biopolymers. Levoglucosan and the related degradation products from cellulose can be utilized as specific and general indicator compounds for the presence of emissions from biomass burning in samples of atmospheric fine particulate matter. This enables the potential tracking of such emissions on a global basis. There are other compounds (e.g. amyrones, friedelin, dehydroabietic acid, and thermal derivatives from terpenoids and from lignin—syringaldehyde, vanillin, syringic acid, vanillic acid), which are additional key indicators in smoke from burning of biomass specific to the type of biomass fuel. The monosaccharide derivatives (e.g. levoglucosan) are proposed as specific indicators for cellulose in biomass burning emissions. Levoglucosan is emitted at such high concentrations that it can be detected at considerable distances from the original combustion source.
Article
Very little is currently known about the relationship between exposure to different sources of ambient ultrafine particles (PM0.1) and human health effects. If human health effects are enhanced by PM0.1’s ability to cross cell membranes, then more information is needed describing the sources of ultrafine particles that are deposited in the human respiratory system. The current study presents results for the source apportionment of airborne particulate matter in six size fractions smaller than 1.8 μm particle diameter including ultrafine particles (PM0.1) in one of the most polluted air basins in the United States. Size-resolved source apportionment results are presented at an urban site and rural site in central California’s heavily polluted San Joaquin Valley during the winter and summer months using a molecular marker chemical mass balance (MM–CMB) method. Respiratory deposition calculations for the size-resolved source apportionment results are carried out with the Multiple Path Particle Dosimetry Model (MPPD v 2.0), including calculations for ultrafine (PM0.1) source deposition.
Article
The long-range transport of North African dust to the Middle East, Europe, South America, and the Caribbean has been well documented during the past 25 years. With the advent of routine collection and analysis of fine aerosols at national parks, monuments, and wilderness areas in the continental United States, these North African dust incursions can now be tracked, characterized, and quantified across much of the eastern half of the United States. Identification of the North African source of these dust episodes is confirmed by mass distribution measure- ments, a characteristic A1/Ca ratio, isentropic backward air mass trajectories, and sequential plots of the spatial distribution of the dust plumes. North African dust incursions into the continental United States persist for-10 days and occurred, on average, 3 times per year from 1992 to 1995. Fine soil mass usually exceeds 10 tg m -3 during these dust episodes and dominates local fine soil dust by an order of magnitude or more, even in the so-called "dust bowl" states of the central United States. Size-resolved measurements of elemental composition taken during July 1995 in- dicate that the mass mean diameter of the transported North African dust is < 1 tm. The high mass scattering efficiency and abundant particle surface area associated with these submicron soil aerosols could have important consequences for both the radiative balance of the region and the chemistry of the local aerosols during summer when the long-range transport of North African dust to the United States is most common.
Article
Size-segregated measurements of aerosol mass and composition are used to determine the composition and seasonal variations of natural and anthropogenic aerosols at Mauna Loa Observatory (MLO) from 1993 through 1996. Although the springtime transport of Asian dust to MLO is a well-documented phenomenon, this study shows that fine anthropogenic aerosols, including sulfur, black carbon, and enriched trace metals such as As, Cu, Pb, and Zn, are also routinely transported to MLO each spring. It is estimated that at least one third of the sulfate measured at MLO during the spring is anthropogenic. In addition, indirect measurements indicate that the organic aerosol concentrations are often comparable to the sulfate concentrations. This study also combines size- and time-resolved aerosol composition measurements with isentropic, backward air-mass trajectories and gas measurements of 222Rn, CH4, CO, and CO2 to identify some potential source regions of the anthropogenic aerosols. Three types of long-range transport episodes are identified: (1) anthropogenic aerosols mixed with Asian dust, (2) Asian pollution with relatively small amounts of soil dust, and (3) biomass burning emissions from North America. This study shows that anthropogenic aerosols and gases can be efficiently transported to MLO from both Asia and North America during the spring.
Article
The long-range transport of North African dust to the Middle East, Europe, South America, and the Caribbean has been well documented during the past 25 years. With the advent of routine collection and analysis of fine aerosols at national parks, monuments, and wilderness areas in the continental United States, these North African dust incursions can now be tracked, characterized, and quantified across much of the eastern half of the United States. Identification of the North African source of these dust episodes is confirmed by mass distribution measurements, a characteristic Al/Ca ratio, isentropic backward air mass trajectories, and sequential plots of the spatial distribution of the dust plumes. North African dust incursions into the continental United States persist for ∼10 days and occurred, on average, 3 times per year from 1992 to 1995. Fine soil mass usually exceeds 10 μg m−3 during these dust episodes and dominates local fine soil dust by an order of magnitude or more, even in the so-called “dust bowl” states of the central United States. Size-resolved measurements of elemental composition taken during July 1995 indicate that the mass mean diameter of the transported North African dust is
Article
Molecular marker compounds that can be used to trace cigarette smoke particles in the outdoor urban atmosphere are identified. While the most abundant resolved organic compounds present are nitrogen-containing heterocyclics (e.g., nicotine), other potential tracers that will be more stable in the outdoor urban atmosphere also are found. Iso- and anteisoalkanes (C[sub 29]-C[sub 34]) are enriched in cigarette smoke particles and show a concentration pattern characteristic of tobacco leaf surface waxes that is distinctly different from leaf surface abrasion products shed from plant leaves that grow in the Los Angeles area. Relative to major leaf surface wax n-alkanes, these iso- and anteisoalkanes are enriched by a factor of more than 40 in tobacco and tobacco smoke particles as compared to leaf surface waxes from Los Angeles area plants. It is found that the iso- and anteisoalkanes concentration pattern generated by cigarette smoke is preserved in the urban atmosphere and is measured at levels that are comparable to emissions estimates based on daily cigarette consumption. 109 refs., 5 figs., 2 tabs.
Article
On the basis of dust-loadings, haze distribution, and the mineralogical, chemical and biological compositions of soil-sized particulates, the region over which transport by the Atlantic northeast trades dominates the supply of land-derived materials to the equatorial North Atlantic has been demonstrated.Within this “dust envelope” the input of the elements Al, Fe, Mn, Cr, Co, Ni, Cu, Zn and Pb to the sea surface via the deposition of soil-sized particulates from the northeast trades has been compared to their output via deep-sea sedimentation. The comparison has been made in terms of the total sediments and of their detrital and authigenic fractions, and the deposits have been divided into marginal and intermediate types on the evidence of their depositional environments.In the equatorial eastern North Atlantic underlying the northeast trades, soil-sized atmospheric particulates are a significant source of all the elements to the deep-sea sediments. In marginal regions the contribution of the total atmospheric input to the total sediment output ranges from 37% to 95%, and in the intermediate regions from 25% to ∼ 100%.The soil-sized particulates make their highest contribution to the detrital fractions of the sediments, and the detrital particulate input of Al, Fe, Cr, Mn, Co, Ni, Cu, and Zn constitutes an average of ∼ 85% of the detrital sediment output in both marginal and intermediate regions.However, the particulates make a much smaller contribution to the authigenic fractions of the sediments. For example, in both marginal and intermediate regions the authigenic atmospheric inputs of Mn, Co, Ni and Cu constitute 25% of the authigenic output required by the sediments.
Article
To investigate the size resolved physico-chemical properties of aerosols transported from the eastern Asian Continent following the winter monsoons, an intensive field experiment was conducted in Taipei, Taiwan in January 2003. Mass concentration and the abundance of major functional groups in size-segregated aerosol samples were measured. The size distribution parameters of the aerosol mass and the associated functional groups were analyzed. The results of the infrared spectroscopic analysis showed that the contents of sulfate and ammonium in Taipei's sub-micron aerosols were significantly increased due to continental pollution. In addition, the Asian outflow aerosols contained higher levels of silicate and nitrate in the super-micron size range. The size-resolved functionalities of the aerosol samples collected during Asian outflow episodes were compared with those of local pollution samples. This comparison revealed that ammonium and sulfate generally coexisted in sub-micron aerosols, suggesting that there are substantial emissions of ammonia to neutralize the acidity of sulfate in the region from eastern China to northern Taiwan. The nitrate had a bimodal distribution over the size range between 0.1 and 10 μm. A significant enhancement was found in coarse nitrate during the Asian outflow episodes, implying heterogeneous reactions of nitric acid on the surface of dust and sea salt particles during the transport processes. High concentrations of sub-micron ammonium nitrate aerosols were observed prior to the frontal passage and served as an important indicator of local photochemical pollution. The aliphatic and carbonyl carbon in the aerosols were suggested as being mostly due to local pollution in Taipei. Nevertheless, our analysis found that the aerosols of Asian outflows had a higher infrared absorbance ratio of carbonyl to aliphatic carbon than those of the local pollution. The enrichment of carbonyl carbon in the Asian outflow aerosols is most likely due to the emissions of biomass burning aerosols in the eastern China.
Article
Conventional risk assessment studies provide no detailed information about the role of specific sources determining the total carcinogenic and mutagenic potencies of PAH mixtures on humans health. In this study, the main emission sources of 11 particle-phase PAHs listed as carcinogenic and mutagenic agents by the IARC were identified by a risk apportionment method. The contribution of sources to the total concentration of PAHs in the study area was also quantified. A receptor model based on factor and multiple linear regression analyses was applied to estimate the source-specific risk associated to PAH inhalation in an urban background area of a large city (Venice-Mestre, Northern Italy). The proposed approach has discriminated the sources of mutagenic and carcinogenic congeners and their role in determining a serious hazard for human health. Results, interpreted on the basis of seasonal variations and atmospheric conditions, have shown that even though domestic heating is the main source of total PAHs
Article
An air quality model that follows the evolution of single particles in the atmosphere has been combined with new emissions measurements and then used to predict the size distribution and chemical composition of the airborne fine particle mixture observed at Long Beach, Fullerton, and Riverside, CA, during September 1996. Model predictions show good agreement with ambient measurements of particle size and chemical composition at all three air monitoring sites. The air quality model is used to separately track individual particles released from different sources as they evolve over time. Four major classes of particles are observed:  (1) large mineral dust and road dust particles that accumulate only small amounts of secondary aerosol products; (2) primary combustion particles (released initially from diesel vehicles, noncatalyst gasoline-powered vehicles, and food processing) that grow by accumulation of secondary reaction products; (3) sea salt particles that are almost completely transformed by conversion from NaCl to NaNO3 during transport across the air basin; and (4) sulfate-containing nonsea salt background particles advected into the air basin from upwind over the ocean. The sulfate-containing nonsea salt background particles have an initial PM2.5 concentration of only 8 μg m-3, but they accumulate significant secondary aerosol reaction products to produce a largely nitrate-containing aerosol having a PM2.5 concentration of 40 μg m-3 by the time that the air masses studied here reach Riverside, CA.
Article
Fine organic particulate matter emitted from an industrial-scale boiler burning no. 2 distillate fuel oil has been characterized on a molecular basis using GC/MS techniques. Most of the identified compound mass consists of n-alkanoic acids (42.0−51.5%), aromatic acids (5.8−22.6%), and n-alkanes (6.7−25.0%). Polycyclic aromatic hydrocarbons (PAH) and oxygenated PAH (oxy-PAH) together comprise 3.1−8.6% of the identifiable mass and together with chlorinated compounds (5.8−16.4%) show the largest variations in emission rates between the two experiments reported here. An increase in chlorinated compound emissions between tests is accompanied by a similar increase in elemental carbon (i.e., soot) and PAH emissions, which may follow the results of laboratory experiments that suggest that the presence of chlorinated compounds can enhance both soot and PAH formation. Differences between the hopanes distribution in the boiler exhaust versus that found in both vehicle exhaust and in the southern California atmosphere suggest that the oil-fired boiler exhaust is at most a minor contributor to the atmospheric aerosol, which is consistent with inferences drawn from local emission inventories.
Article
Green and dead leaves from 62 plant species characteristic of the Los Angeles area were harvested and composited according to the actual leaf mass distribution for that area. To simulate leaf surface abrasion by the wind, the leaf composites were agitated in clean Teflon bags while a purified airstream flowed through. Fine particles (d_p ≤ 2 µm) shed from the leaf surfaces were extracted and analyzed using gas chromatography/mass spectrometry. Organic constituents including n-alkanes, n-alkanoic and n-alkenoic acids, n-alkanols, n-alkanals, terpenoid compounds, and trace amounts of PAH were identified and quantified. n-Alkanes showed similar concentrations in both dead and green leaf surface matter; mono-, sesqui-, and triterpenoids were depleted in dead leaf material while n-alkanoic acids were enriched in dead leaf abrasion products. It is shown that the higher molecular weight n-alkanes (C_(27)-C_(33)), with their pronounced odd/even carbon number predominance, provide a suitable marker compound assemblage for tracing vegetative detritus in the urban atmosphere.
Article
More than 100 organic compounds are quantified in these samples, including n-alkanes, n-alkanoic acids, n-alkenoic acids, n-alkanals, n-alkanols, benozoic acids, benzaldehydes, polyalkylene glycol ethers, PAH, oxy-PAH, steranes, hopanes, natural resins and other compound classes. Paved road dust acts as a repository for vehicle-related particles, which can then be resuspended by the passing traffic. To evaluate the contributions from major urban sources to the road dust complex, source profiles representing different types of vehicle exhaust, brake dust, tire debris, and vegetative detritus are compared, and their fractional contributions are estimated using several groups of organic tracer compounds. -from Authors
Article
Fugitive dust from the erosion of arid and fallow land, after harvest and during agricultural activities, can at times be the dominant source of airborne particulate matter. In order to assess the source contributions to a given site, chemical mass balance (CMB) modeling is typically used together with source-specific profiles for organic and inorganic constituents. Yet, the mass balance closure can be achieved only if emission profiles for all major sources are considered. While a higher degree of mass balance closure has been achieved by adding individual organic marker compounds to elements, ions, EC, and organic carbon (OC), major source profiles for fugitive dust are not available. Consequently, neither the exposure of the population living near fugitive dust sources from farm land, nor its chemical composition is known. Surface soils from crop fields are enriched in plant detritus from both above and below ground plant parts; therefore, surface soil dust contains natural organic compounds from the crops and soil microbiota. Here, surface soils derived from fields growing cotton, safflower, tomato, almonds, and grapes have been analyzed for more than 180 organic compounds, including natural lipids, saccharides, pesticides, herbicides, and polycyclic aromatic hydrocarbon (PAH). The major result of this study is that selective biogenically derived organic compounds are suitable markers of fugitive dust from major agricultural crop fields in the San Joaquin Valley. Aliphatic homologs exhibit the typical biogenic signatures of epicuticular plant waxes and are therefore indicative of fugitive dust emissions and mechanical abrasion of wax protrusions from leaf surfaces. Saccharides, among which α- and β-glucose, sucrose, and mycose show the highest concentrations in surface soils, have been proposed to be generic markers for fugitive dust from cultivated land. Similarly, steroids are strongly indicative of fugitive dust. Yet, triterpenoids reveal the most pronounced distribution differences for all types of cultivated soils examined here and are by themselves powerful markers for fugitive dust that allow differentiation between the types of crops cultivated. PAHs are also found in some surface soils, as well as persistent pesticides, e.g., DDE, Fosfall, and others.
Article
We present the physical and chemical characterization of particulate matter (PM2.5) emissions from simulated agricultural fires (AFs) of surface residuals of two major grain crops, rice (Oryza sativa) and wheat (Triticum aestivum L.). The O2 levels and CO/CO2 ratios of the open burn simulations are typical of the field fires of agricultural residues. In the AF plumes, we observe predominantly accumulation mode (100–1000 nm) aerosols. The mean PM2.5 mass emission factors from replicate burns of the wheat and rice residuals are 4.7±0.04 and 13.0±0.3 g kg−1 of dry biomass, respectively. The combustion-derived PM emissions from wheat are enriched in K (31% weight/weight, w/w) and Cl (36% w/w), whereas the PM emissions from rice are largely carbonaceous (84% w/w). Molecular level gas chromatography/mass spectrometry analysis of PM2.5 solvent extracts identifies organic matter that accounts for as much as 18% of the PM mass emissions. A scarcity of detailed PM-phase chemical emissions data from AFs required that comparisons among other biomass combustion groups (wildfire, woodstove, and fireplace) be made. Statistical tests for equal variance among these groups indicate that the degree to which molecular emissions vary is compound dependent. Analysis of variance testing shows significant differences in the mean values of certain n-alkane, polycyclic aromatic hydrocarbon (PAH), oxy-PAH, and sugar marker compounds common to the biomass combustion types. Individual pairwise comparisons of means at the combustion group level confirm this result but suggest that apportioning airborne PM to these sources may require a more comprehensive use of the chemical emissions fingerprints. Hierarchical clustering of source test observations using molecular markers indicates agricultural fuels as distinct from other types of biomass combustion or biomass species. Rough approximations of the total potential PM2.5 emissions outputs from the combustion of the wheat and rice surface residues are given. This agricultural activity could significantly contribute to emissions inventories at regional, national, and global geographic levels.
Article
Wind-borne dust collections have been made on the island of Barbados; and the day by day amounts have been recorded for several months, commencing August 1965. From mineralogical and biological examinations, this dust is most likely to be derived from the European-African continents.The fungus and magnetic contents of the dust show a marked seasonal variation in accordance with the shift in wind patterns off the African coast. The average concentration of this dust is about 5 × 10−12 cm3 per cm3 of air and making plausible estimates for the fallout rate, its contribution to the deep sea sedimentation of the western tropical Atlantic is about 0·6 mm/1000 yr, suggesting that a goodly fraction of the deep sea clay is indeed wind transported.The size distribution of the Barbados dust, which is mainly below 20 μ, can be argued into agreement with the distribution in the Atlantic sediments. Both the dusts and the deep-sea sediments have similar mineral compositions. The finding of dolomite in the Barbados dusts has led to an explanation of its occurrence in the Atlantic deposits and to a discovery of a dolomite gradient across the ocean.Along with various marine organisms and a great number of fungus hyphae, fresh water diatoms, in particular Melosira granulata, occur in all the Barbados dusts. This diatom is found in Atlantic sediments; and previous studies indicated that in certain core sections it is present in abundance. Occasionally Denticula elegans is also found and, since this fresh water diatom only inhabits cold running waters, there is strong indication that the dusts arriving at Barbados could have come, in part and at various times, from a mountainous region.
Article
Fugitive dust emissions from cattle feedlots and open lot dairies are substantial. In order to determine the contribution of intensive cattle operations on ambient PM levels, more knowledge besides the elemental composition is necessary in order to distinguish between airborne PM from nearby agricultural fields, barren lands, or dirt roads. Here, as part of the San Joaquin Valley Fugitive Dust Characterization Study, surface soil samples collected from feedlots and open lot dairy farms are investigated for potential source specific molecular marker compounds. More than 100 organic compounds were quantified including: n-alkanes, n-alkanoic acids, n-alkenoic acids, n-alkanols, n-alkanals, n-alkan-2-ones, steroids, triterpenoids, isoprenoids, and tocopherols (vitamin E) and metabolites. Biohydrogenation of plant lipids and sterols in the rumen results in distinctive alteration products. Animal and plant derived steroids are most abundant. Here, it is shown that 5β-stigmastanol and epi-5β-stigmastanol, two biohydrogenation products of sitosterol and stigmasterol, are the most distinctive molecular marker compounds. While stearic (C18) and palmitic (C16) acids are as individual compounds not source specific, biohydrogenation of the more abundant C18 unsaturated fatty acids, causes the ratio of C18/C16 fatty acids to shift from below 0.5 for vegetation to an average of 3.0±0.7. Consequently, the C18/C16 fatty acid ratio is unique and can be used as well in source apportionment studies.
Article
This study targets understanding the secondary sources of organic aerosol in Mexico City during the Megacities Impact on Regional and Global Environment (MIRAGE) 2006 field campaign. Ambient PM2.5 was collected daily at urban and peripheral locations. Particle-phase secondary organic aerosol (SOA) products of anthropogenic and biogenic precursor gases were measured by gas chromatography mass spectrometry. Ambient concentrations of SOA tracers were used to estimate organic carbon (OC) from secondary origins (SOC). Anthropogenic SOC was estimated as 20–25% of ambient OC at both sites, while biogenic SOC was less abundant, but was relatively twice as important at the peripheral site. The OC that was not attributed secondary sources or to primary sources in a previous study showed temporal consistency with biomass-burning events, suggesting the importance of secondary processing of biomass-burning emissions in the region. The best estimate of biomass-burning-related SOC was in the range of 20–30% of ambient OC during peak biomass burning events. Low-molecular weight (MW) alkanoic and alkenoic dicarboxylic acids (C2–C5) were also measured, of which oxalic acid was the most abundant. The spatial and temporal trends of oxalic acid differed from tracers for primary and secondary sources, suggesting that it had different and/or multiple sources in the atmosphere.
Article
Protection of public health from the effects of air particulate matter (PM) requires measurements and methods that assess the PM chemical constituents, physical properties, and their sources. Sampling was conducted at three sites in the Baltimore area: a source-oriented (industrial) area in south Baltimore (FMC site), and two receptor area sites (Clifton Park and Ponca Street). FMC measurements were made for the initial 1-month of the project; Clifton measurements lasted for about 2 months, while measurements at Ponca Street lasted for about 9.5 months. Pollutant samples were collected at intervals ranging from 5 min to 1 h using semi-continuous monitors for PM2.5 mass, sulfate, nitrate, elemental and organic carbon, particle number size distributions (10–20,000 nm), CO, NOx, O3, 11 metals, and mass spectra of individual particles, throughout the project. In addition to standard meteorological measurements, a 3D-sonic anemometer and a LIDAR system were operated during selected periods as were a rotating drum impactor with 3- to 6-h resolution and a filter/PUF sampler for 3-h measurements of organic compounds. Standard speciation and FRM mass measurements were also made. This report describes the types of measurements that were made at the various sites of the Baltimore Supersite program as well as presents the summary statistics for some of the PM measurements that have been made. The measurements of aerosol mass, major components, and size distribution data for the three sites are compared. Results show comparable PM concentrations at Ponca Street and Clifton Park. Increased variability was observed at Ponca Street.
Article
Mounting evidence suggests that air pollution contributes to the large global burden of respiratory and allergic diseases, including asthma, chronic obstructive pulmonary disease, pneumonia, and possibly tuberculosis. Although associations between air pollution and respiratory disease are complex, recent epidemiologic studies have led to an increased recognition of the emerging importance of traffic-related air pollution in both developed and less-developed countries, as well as the continued importance of emissions from domestic fires burning biomass fuels, primarily in the less-developed world. Emissions from these sources lead to personal exposures to complex mixtures of air pollutants that change rapidly in space and time because of varying emission rates, distances from source, ventilation rates, and other factors. Although the high degree of variability in personal exposure to pollutants from these sources remains a challenge, newer methods for measuring and modeling these exposures are beginning to unravel complex associations with asthma and other respiratory tract diseases. These studies indicate that air pollution from these sources is a major preventable cause of increased incidence and exacerbation of respiratory disease. Physicians can help to reduce the risk of adverse respiratory effects of exposure to biomass and traffic air pollutants by promoting awareness and supporting individual and community-level interventions.
Article
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.
Article
The size distributed composition of ambient aerosols is used to explore seasonal differences in particle chemistry and to show that dry deposition fluxes of soluble species, including important plant nutrients, increase during periods of biomass (sugar cane trash) burning in São Paulo State, Brazil. Measurements were made at a single site centrally located in the State's sugar cane growing region but away from the immediate vicinity of burns, so that the airsampled was representative of the regional background. Calculation of ion equivalent balances showed that during burning periods smaller particles (Aitken and accumulation modes) were more acidic, containing higher concentrations of SO4(2-), oxalate, NO3-, HCOO-, CH3COO-, and CI-, but insufficient NH4+ and K+ to achieve neutrality. Larger particles showed an anion deficit due to the presence of unmeasured ions and comprised resuspended dusts modified by accumulation of nitrate, chloride, and organic anions. Increases of resuspended particles during the burning season were attributed to release of earlier deposits from the surfaces of burning vegetation as well as increased vehicle movement on unsurfaced roads. During winter months the relative contribution of combined emissions from road transport and industry diminished due to increased emissions from biomass combustion and other activities specifically associated with the harvest period. Positive increments in annual particulate dry deposition fluxes due to higher fluxes during the sugar cane harvest were 44.3% (NH4+), 42.1% (K+), 31.8% (Mg2+), 30.4% (HCOO-), 12.8% (CI-), 6.6% (CH3COO-), 5.2% (Ca2+), 3.8% (SO4(2-)), and 2.3% (NO3-). Na+ and oxalate fluxes were seasonally invariant. Annual aerosol dry deposition fluxes (kg ha(-1)) were 0.5 (Na+), 0.25 (NH4+), 0.39 (K+), 0.51 (Mg2+), 3.19 (Ca2+), 1.34 (Cl-), 4.47 (NO3-), 3.59 (SO4(2-)), 0.58 (oxalate), 0.71 (HCOO-), and 1.38 (CH3COO-). Contributions of this mechanism to combined aerosol dry deposition and precipitation scavenging (inorganic species, excluding gaseous dry deposition) were 31% (Na+), 8% (NH4+), 26% (K+), 63% (Mg2+), 66% (Ca2+), 32% (Cl-), 33% (NO3-), and 36% (SO4(2-)).
Article
The goal of the regional haze mitigation program in the United States is to attain "natural conditions" in national parks and wilderness areas by 2064. Results of research investigations on background concentrations of sea salt and biogenic organic matter, of episodic Saharan and Asian dust, and of carbon from natural fires were reviewed to provide a basis for making site-specific estimates of what the concentrations of atmospheric fine particulate matter components might be under natural conditions in the Southeastern United States. Based on this review, rough estimates were made of potential contributions of these aerosol components to natural background visibility. Natural organic particles were the dominant influence on the rate of visibility improvement required to reach natural conditions at an inland, mountainous location, and organic particles and sea salt were the dominant influences on the rate at a coastal location. African dust also had a large episodic effect, but the current regulatory approach is not designed to address episodic background variations. Insufficient data exist to quantify the contributions of wildfires with any detail, although global air pollution modeling provides insight, and their emissions can be locally dominant. Conservative regional refinements to the default natural background estimates do not greatly alter the region-wide rates of reduction of ambient particulate matter concentrations that will be needed to accomplish the first phase of the regional haze program. However, refinements at specific Class I areas may have considerable influence on defining the nature (magnitude and spatial and temporal distribution) of local emission reduction efforts there.
  • J C Chow
  • J G Watson
  • D H Lowenthal
  • P A Solomon
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Chow, J. C., Watson, J. G., Lowenthal, D. H., Solomon, P. A., Magliano, K. L., Ziman, S. D., et al. (1993). PM10 and PM2.5 compositions in California San Joaquin Valley. Aerosol Science and Technology, 18(2), 105–128.
The Florida sugar industry – Its evolution and prospects
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Buzzanell, P., Lord, R., & Brown, N. B., Jr. (1992). The Florida sugar industry – Its evolution and prospects. Sugar and Sweetener, (June), 11–34.
Comparison of burning vs. non-burning of Cane
  • L G Nickell
Nickell, L. G. (1970, November). Comparison of burning vs. non-burning of Cane. In Hawaiian Sugar Technology Reports, 29th Annual Conference (pp. 101–110).
The climate and weather of Florida
  • J A Henry
  • K M Portier
  • J Coyne
Henry, J. A., Portier, K. M., & Coyne, J. (1994). The climate and weather of Florida. Sarasota, FL: Pineapple Press Inc.