Environ. Sci. Technol. 2011, 45, 930–936

ambient PM (8-10). To characterize the contributions from Characterization of Saccharides in these biologically derived sources, saccharides have recently Size-fractionated Ambient been proposed as molecular tracers because of the unique association between specific saccharide compounds and Particulate Matter and Aerosol these sources (2). For example, the anhydrous saccharide levoglucosan was a well-established marker for burning of Sources: The Contribution of biomass (11, 12), although recent study had indicated the possibility of levoglucosan oxidation in the atmosphere (13); Primary Biological Aerosol Particles glucose, sucrose, and trehalose have also been proposed as marker compounds for fugitive dust from biologically active (PBAPs) and Soil to Ambient surface soils (4); mannitol and arabitol have been proposed Particulate Matter as tracers for airborne fungal spores (7, 14). Among the categories of biologically derived PM sources, less is known about the contribution of soil dust and PBAPs † ,‡ YULING JIA AND MATTHEW FRASER* to ambient PM compared to biomass combustion, particu- Department of Environmental Molecular and Toxicology, larly on a regional scale. Using saccharides as source-specific Oregon State University, Corvallis, Oregon, United States, and markers, Bauer et al. (15) estimated between 3% and 7% of Global Institute of Sustainability, Arizona State University, the PM10 mass at a suburban sampling location in Vienna, Tempe, Arizona, United States Austria is derived from fungal contribution. Jia et al. (16) estimated that primary biologically derived carbon sources Received September 21, 2010. Revised manuscript received (including soil and PBAP) contributed between 5% and 16% November 30, 2010. Accepted December 9, 2010. to the measured PM2.5 at three sites in the southwest U.S. and around 21% to PM10 at a suburban site in Arizona. Despite the limited number of studies on quantifying the contributions of soils and PBAPs to ambient aerosol, there Size-fractionated (equivalent to ambient PM2.5 and PM10) is an overwhelming need to characterize biologically derived local soil, plant, and spore samples were collected in the Sonoran PM sources, especially in regions where the role of agricultural Desert near Phoenix, AZ and measured for saccharide and natural sources is greater than more traditional urban content with the goal of characterizing ambient particulate sources such as mobile sources. matter sources including soil and primary biological aerosol One way to advance the characterization of soil and PBAP particles (PBAPs) from plants and fungi. Different saccharide as PM sources is to study and compare their molecular marker compositions were observed among soil, plant, and spore samples composition with ambient aerosols on a size-fractionated level. Previous studies have reported the major saccharide and between PM2.5 and PM10 fractions. The total measured content in various bulk soils (2, 4, 17) and PBAPs including nonlevoglucosan saccharide content relative to PM mass yeasts, fungal spores, and pollens (18-20). However, no in ambient aerosols collected in a Phoenix suburb (Higley) was studies have been done to characterize the saccharide much higher compared to the local soil samples but much source profiles on size levels equivalent to those used for lower compared to the PBAP. The enrichment of saccharides sampling ambient PM. To this end, local soil, plant, and from two saccharide-dominated PM source factors resolved spore samples were collected to augment the data set of by a positive matrix factorization model is also higher than the ambient PM2.5 and PM10 from the suburban sampling saccharide content in the size-fractionated local soil samples, site in Higley, AZ reported by Jia et al. (16). These soil, but lower than that measured in the size-segregated PBAP plant, and spore samples were resuspended and size- samples. This indicates that ambient concentration of particulate segregated to represent material entrained as PM2.5 and PM10, which was then analyzed for saccharide composi- saccharides at Higley was dominated by contributions from tion. The saccharide contents in these potential PM sources PBAPs directly injected into the atmosphere from plants and were compared with those in ambient PM and the source spores rather than from soil and associated biota. Our results also factors isolated using a receptor modeling technique for suggest the contribution to the fine size fraction of ambient both PM2.5 and PM10 levels. The goal of this study was PM from the primary biologically derived sources may be greater to characterize and compare two important biologically than previously acknowledged. derived PM sources (soil and PBAP) and their contributions to different size fractions of ambient PM in an arid Introduction environment. To the best of our knowledge, this study is the first of its kind to compare the saccharide content Sources of ambient particulate matter (PM) are numerous. between the fine and coarse fraction of soil and PBAP types Apart from the better-known anthropogenic sources, the and to relate their relative contributions to ambient PM emissions from biologically derived sources, including bio- using saccharides as molecular markers. mass burning (1), the atmospheric entrainment of soil and - dust (2 4), and primary biological aerosol particles (PBAPs) Experimental Section such as spores, pollens, fungi, algae, bacteria, virus, and Ambient PM Sampling. The sampling of ambient PM was fragments of plants and animals (5-7), also contribute conducted from January to April 2008 near Higley, AZ (33°18′ significantly to both the national and global loadings of N, 111°43′ W), a suburb of Phoenix. Both PM2.5 and PM10 samples were collected simultaneously using high-volume * Corresponding author phone: 1-480-965-3489; e-mail: air sampler and low-volume air sampler. A total of 45 sets [email protected]; address: Global Institute of Sustainability, Arizona State University, PO Box 875402, Tempe, AZ 85287. of PM2.5 and 46 sets of PM10 samples were obtained. A † Oregon State University. detailed description of the sampling and results of aerosol ‡ Arizona State University. analysis can be found in Jia et al. (16).

930 9 ENVIRONMENTAL SCIENCE & TECHNOLOGY / VOL. 45, NO. 3, 2011 10.1021/es103104e  2011 American Chemical Society Published on Web 01/07/2011 Soil Sampling. During the ambient PM sampling program, cosan and levoglucosan was not detected in soil and PBAP soil samples were taken in the vicinity of the Higley sampling samples in current study. The average total measured site in January and April 2008. Samples were taken from the saccharides ranged from 17 µgg-1 (in PM2.5 fraction of road surface (0-5 cm depth) in uncultivated areas (no current dust samples in January) to 284 µgg-1 (in PM10 fraction of agricultural practice), fields under current agricultural cul- road dust samples in April) for all soil samples. The measured tivation, and alongside major roads. A total of 28 soil samples organic carbon ranged from 2252 to 43900 µgg-1 (Table S3) was obtained (half in January and half in April), which and the carbon content of measured saccharides for all soil included 14 agricultural soil samples, 6 uncultivated soil samples represented from 0.05% (in both PM2.5 and PM10 samples, and 8 road dust samples. Table S1 in the Supporting fraction of road dust samples in January) to 1.4% (in PM2.5 Information lists the date, the sample type, a brief description, fraction of currently uncultivated soil samples in April) of and taxonomy of the soil samples taken in this study. Each the measured organic carbon (Table S4). There have been sample was collected in prebaked glass jars (250 mL) sealed several prior literature reports on the saccharide content of with Teflon-lined lids and Teflon tape and stored in a freezer soils at different locations, and results from these studies are at -20 °C after collection. Prior to analysis, each sample was summarized in Table S5. Note that all of these literature dried at 110 °C for 24 h and then resuspended in a 1-L heavy reports were based on analysis of bulk soil samples with wall filtering flask. As atmospheric entrainment of crustal particle diameter less than 0.6 mm, and not for size-selected material is a complicated process, size-segregated samples soil samples representative of soil resuspended as either approximating fractions equivalent to PM10 and PM2.5 PM2.5 or PM10. For comparison with literature reports, soil were collected using a simplistic approach using cyclone samples from this current study were used to collect particles separators (URG models 2000-30EA and 2000-30EC). Three with diameter less than 0.6 mm and analyzed following the 47-mm filters were collected in parallel for each resus- procedure described by Medeiros et al. (17). Characterization pension including one Teflon (Whatman) and two quartz of these larger particles showed less enrichment of saccha- (Whatman) filters. Figure S1 shows the experimental setup rides compared to size-selective soil representing resuspen- of the resuspension and sampling. sion of dust as PM2.5 or PM10 by a factor of 2-8 (unpublished Plant and Spore Sampling. A total of 9 plant and spore data). If this increased enrichment is incorporated into the samples was obtained representing vegetation and fungi data interpretation, the total saccharide levels measured in common to the Sonoran Desert of the southwestern US (Table Higley soil PM2.5 and PM10 samples were within the range S2). Plant samples included five species (Prosopis juliflora, of those reported in different soil types at various locations Simmondsia chinensis, Atriplex lentiformis, Baccharis saro- elsewhere (2, 4, 17, 23). throides, and Justicia californica) and spore samples included In general, saccharide concentrations measured in both three species (Podaxis pistillaris, Battarrea phalloides, and the PM2.5 and PM10 fraction of the resuspended soil collected Aspergillus niger). After collection, plant samples were air- in January were not statistically different from those collected dried for a week and oven-dried at 110 °C for 24 h prior to in April (Mann-Whitney Rank Sum test, P ) 0.21 for PM2.5 grinding into powders to represent the milling process of and P ) 0.37 for PM10), likely due to a relative small sample plant vegetation as material is deposited on roads and other size. Similarly, no statistically significant difference was found surfaces and resuspended as dust. The spore samples were between the total measured saccharide to organic carbon gently shaken upside down for the spore particles (2-10 µm ratios in the resuspended soil collected in January and in in diameter) to be released and collected onto precleaned April (Mann-Whitney Rank Sum test, P ) 0.18 for PM2.5 aluminum foil. Particles from these pretreated samples were and P ) 0.29 for PM10). then placed in the filtering flask for resuspension as described The disaccharide trehalose has been previously reported above and shown in Figure S1. As with the soil sampling, one in many studies as the most abundant sugar in soil (2, 3, 17), 47-mm Teflon filter and two 47-mm quartz filters were and trehalose comprised on average about 40-70% of the collected in parallel for each resuspension. total measured saccharides in Higley soil samples, with the Sample Analysis. All samples obtained in this study were greatest levels found in those that were not under active analyzed for PM mass, elemental and organic carbon content cultivation. Trehalose, known to be a fungal metabolite as (EC and OC), and organic speciation. Specifically, Teflon filter well as a stress protectant for the soil microbial community samples were weighed before and after sampling for mass (24), was in general more enriched in the fine fraction (PM2.5) determination using a microbalance under controlled tem- of soil samples compared to the coarse portion (PM - )of - ° - 2.5 10 perature (22 24 C) and humidity conditions (45 55%); a the soils (no statistically significant difference between PM2.5 × 1cm 1.5 cm punch was removed from each quartz filter and PM10, Mann-Whitney Rank Sum test, P > 0.05). This sample and analyzed for EC and OC content using a Sunset implies that the re-entrainment of trehalose occurs prefer- Laboratory thermo-optical carbon analyzer following the entially in the fine size range and might explain the difference method described by Birch and Cary (21), accuracy of this between total saccharide measures of size selected PM (i.e., method had been tested by several method intercomparison PM2.5 and PM10) compared to bulk soil characterization. - studies and was within 5 10% (22); the remainder of the The second most abundant saccharide in soils was glycerol, quartz filter from each source sample was extracted and which contributed on average between 15% and 32% of the analyzed for saccharide composition. Detailed procedures total measured saccharides. Glycerol in soils was found to for sample extraction and analysis can be found elsewhere comprise a higher percentage of the total measured sac- (16). charides in the fine fraction of soils than in the coarse fraction (no statistically significant difference between PM2.5 and Results and Discussions PM10, Mann-Whitney Rank Sum test, P > 0.05). This is Saccharides in Size-fractionated Soil Samples. Table S3 consistent with the association of glycerol with biomass summarizes the range and average concentrations of the burning, and in the area near the Higley sampling site, this measured saccharide compounds in size separated samples may represent the burning of crops and vegetation residue equivalent to PM2.5 and PM10 for each of the three types of in the fields (25). Glucose was the third most dominant soil collected in January and April near the Higley sampling saccharide, followed by sucrose, and each contributed on site. It should be noted that an important anhydrous average from 9% to 23% and from 4% to 12% to the total saccharide levoglucosan that is often measured in ambient measured saccharides, respectively. No uniform enrichment PM samples is excluded from discussions in this manuscript pattern of glucose or sucrose was found in either the PM2.5 as soil and PBAPs are not considered as sources of levoglu- or PM10 fraction of soils, but glucose and sucrose did appear

VOL. 45, NO. 3, 2011 / ENVIRONMENTAL SCIENCE & TECHNOLOGY 9 931 TABLE 1. Total Saccharide Content (Excluding Levoglucosan) Relative to PM Mass and Total Carbon Content of Saccharide (Excluding Levoglucosan) Relative to OC in Higley Ambient Aerosols Compared to Local Soil, Plant, and Spore Samples

total saccharide content total carbon content of saccharide (excluding levoglucosan) relative to PM mass (%) (excluding levoglucosan) relative to OC (%) PM2.5 PM10 PM2.5 PM10 ambient PM 0.20 ( 0.25 0.11 ( 0.09 0.26 ( 0.27 0.37 ( 0.37 agricultural soil 0.004 ( 0.007 0.009 ( 0.010 0.32 ( 0.27 0.37 ( 0.43 currently uncultivated soil 0.008 ( 0.014 0.009 ( 0.013 0.97 ( 1.70 0.36 ( 0.51 road dust 0.012 ( 0.020 0.019 ( 0.018 0.47 ( 0.93 0.09 ( 0.05 PBAP - plant 2 ( 23( 2 PBAP - spore 16 ( 722( 8 to be enriched in road dust samples in April as opposed to both mannitol and trehalose in plants has also been attributed agricultural soil and currently uncultivated soil samples to the presence of fungi (34). Apart from mannitol, other (Mann-Whitney Rank Sum test, P < 0.05). Given glucose saccharide polyols were also detected, including glycerol, and sucrose are known as the main components of pollen arabitol, and sorbitol. However, the concentrations of these grains which are used to maintain water content and pollen species were small compared to the four major saccharide viability (26), this observation may be attributable to enrich- species discussed above. ment of pollen grains and fragments in road dust particles. The size-separated spore samples contained higher sac- Sugar polyols (excluding glycerol) were minor saccharide charide contents than the size-separated plant samples, with components in Higley soils, contributing from less than 1% total measured saccharide concentration ranging from 93 to up to 16% of the total measured saccharides, with sorbitol, 268 mg g-1. This measured saccharide content represents arabitol, and mannitol being the dominant polyol species. between 9% and 27% of collected mass. In the spore samples, Sorbitol, a sugar polyol occurring in higher woody plants but trehalose and mannitol were the most dominant saccharide not commonly found in lower plants (27), was mostly compounds, comprising more than 97% of the total measured measured in agricultural soils. By comparison, mannitol, a saccharides. Trehalose and mannitol are well-known fungal sugar polyol that has previously been reported to originate metabolites (35, 36), functioning mainly as storage carbo- from fungal spores (28), was found in slightly higher hydrates and as membrane stabilizers (28, 33). Mandels et concentrations in road dust samples. al. (18) reported that trehalose and mannitol account for Saccharides in Size-fractionated PBAP Samples. The 19% and 2% of the dry weight in spores of the fungus saccharide contents of the locally representative size- Myrothecium verrucaria, respectively. Other literature reports fractionated PBAP samples, i.e., plant and spore samples, suggest mannitol represents between 10% and 15% of the are reported in Table S6. In general, there was no statistically dry weight in spores of the filamentous fungus (Aspergillus significant difference in saccharide profiles between the niger)(20). If the samples analyzed in the present work are PM2.5 and PM10 fraction of the collected samples (Welch’s assumed to contain ∼50% water by weight (37), then the t test, two-tailed, P-values ranging 0.7-0.9). However, the present analysis is consistent with these earlier literature plant and spore samples displayed different patterns in total reports. Other saccharide compounds (such as sucrose and measured saccharide concentration and relative abundance glucose) were also measured in the spore samples, although of saccharides between the two sample categories. at much lower concentrations, a characteristic consistent The six plant samples contained a total measured sac- with higher fungi (Ascomycota and Basidiomycota) (38). charide concentration ranging from 6 to 71 mg g-1, compris- Comparison of Saccharide Composition in Size-frac- ing from 1% to 7% of the measured sample mass, and the tionated Soil and PBAP Samples with Ambient PM Samples. carbon content of measured saccharides also comprising As a way to assess the contribution to ambient PM from the from 1% to 7% of the measured OC. The total measured two major biologically derived sourcesssoil and PBAPsthe saccharide contents (% wet mass) are within the ranges marker composition in these sources can be related to and reported in woody plant samples (29). The most abundant compared with its equivalent in ambient PM. To do so, the saccharide compounds in the collected plant samples were ambient aerosol saccharide concentration at Higley was first sucrose and glucose, with one plant species (Prosopis divided by the corresponding measured PM mass, and then juliflora) particularly enriched in sucrose and another compared on a mass to mass basis with the saccharide (Atriplex lentiformis) enriched in glucose. This is consistent content in the size-fractionated soil, plant, and spore samples with prior knowledge because sucrose and glucose are the collected in this study. Because soil, plant, and spore are not most abundant storage and photosynthetic carbohydrates regarded as potential sources for levoglucosan in aerosols in plants (30). The elevated level of sucrose measured in and very little levoglucosan was quantified in soil, plant, and Prosopis juliflora was likely due to the presence of flowers spore samples in this study, the comparison in the following in the sample, as sucrose is an important sugar in developing discussion will exclude this compound. flower buds (31) and a major component in pollen grains The total saccharide content (excluding levoglucosan) (26). The one exception to the enrichment of sucrose and relative to PM mass in ambient aerosol samples is 0.20% for glucose in plant samples was the dead branches of Prosopis PM2.5 and 0.11% for PM10 (Table 1). When compared to a juliflora, which contained a slightly higher concentration of ratio of saccharide to soil PM mass of 0.01% and 0.02% for trehalose than sucrose and glucose. This particular sample the PM2.5 and PM10 fraction of road dust (which was the also contained approximately an order of magnitude greater highest saccharide content level found in all three types of concentration of mannitol compared to the other plant soil and dust samples in current study), it is clear that the samples. Trehalose and mannitol have been labeled as overall saccharide content was much higher in ambient PM “fungus-specific” saccharides as they are rarely found in than in the resuspended and size-segregated soil samples. plants (28). The presence of trehalose and mannitol in plant This was unexpected because fugitive dust sources including tissues is often associated with desiccation conditions, under agricultural fields, roads, and soil erosion from the sur- which they are produced as protectants against osmotic stress rounding desert locations are believed to be the major and to stabilize dry membranes (32, 33). The detection of contributor to the ambient PM concentrations in the Phoenix

932 9 ENVIRONMENTAL SCIENCE & TECHNOLOGY / VOL. 45, NO. 3, 2011 FIGURE 1. Comparison of the two PMF modeled PM source factors with the saccharide composition in the PM2.5 and PM10 fraction of three soil types at Higley: Modeled Source 1 - Sucrose and trehalose rich bioaerosol; Modeled Source 2 - Glucose and sugar polyol rich bioaerosol. desert area (39, 40). Prior literature reports also propose that sucrose enriched in plant samples and trehalose enriched soils and associated microbiota are a major source contrib- in fungal samples. uting to sugars and polyols in ambient PM (2). If the same Further investigating the PM2.5 and PM10 fraction of comparison is based on saccharide content in OC (based on ambient aerosol and size-fractionated soil and PBAP source carbon content), the saccharide to OC ratio found for soil samples, the data show a higher saccharide percentage samples is still not much higher than the corresponding value relative to PM mass in ambient PM2.5 than PM10 for the for ambient PM samples (Table 1). This indicates there are total measured nonlevoglucosan saccharide content (Table likely other dominant sources contributing to sugars and 1) (Mann-Whitney Rank Sum test, P ) 0.04). However, in polyols in aerosols at Higley in addition to soils and dust soil and PBAP samples, there was no significant difference during the current study period. On the other hand, the in the corresponding ratio of saccharides to PM mass between size-fractionated PBAP samples analyzed in the current the PM2.5 and PM10 fraction (P > 0.05, Mann-Whitney Rank study had total measured nonlevoglucosan saccharide Sum test for soil samples and Welch’s t test for PBAP samples). content ranging from 1% to 27% relative to PM mass and It was previously acknowledged that the contribution of soil from 1% to 36% relative to measured OC (based on carbon particles and PBAPs are mainly associated with coarse fraction content) in the PM2.5 and PM10 fraction of plant and spore of ambient PM (5, 7, 41). However, our data here suggest samples. These values are 1-2 orders of magnitude greater these sources may undergo a series of physical processes than equivalent ratios measured in ambient PM samples, (i.e., resuspension, wetting, drying) which decompose coarse which indicates PBAPssalthough not having been widely particles into finer particles that then become airborne (42), acknowledgedsmay be another important source of or sources with smaller sizes, such as bacteria, may be the ambient aerosol saccharides in addition to soil in the main carrier of saccharides (mainly trehalose) to the fine PM Phoenix desert area. The major nonlevoglucosan saccha- (43). Separately there may be a significant contribution that ride species measured in Higley ambient PM, namely may have been previously underestimated from fine material sucrose, glucose, and trehalose, were also found in in soils or PBAPs that are of microbiological origin (10, 44). significant amount in PBAP samples, with glucose and In a relevant comparison, Puxbaum and Tenze-Kunit (45)

VOL. 45, NO. 3, 2011 / ENVIRONMENTAL SCIENCE & TECHNOLOGY 9 933 FIGURE 2. Comparison of the two PMF modeled PM source factors at Higley (left Y-axis) with the local PBAP sample source profiles (values were averaged from concentrations in particles equivalent to PM2.5 and PM10) (right Y-axis): Modeled Source 1 - Sucrose and trehalose rich bioaerosol; Modeled Source 2 - Glucose and sugar polyol rich bioaerosol. Abbreviations of the PBAP samples: PJ - Prosopis juliflora,SC-Simmondsia chinensis,AL-Atriplex lentiformis,BS-Baccharis sarothroides,JC-Justicia californica,PP-Podaxis pistillaris,BP-Battarrea phalloides,AN-Aspergillus niger. unexpectedly measured a large fraction of atmospheric Comparison of Saccharide Composition in Soil and cellulose in fine aerosol fractions (<1.6 µm AD) at a downtown PBAP Sample with Modeled PMF Source Factors. Another site in Vienna. The origin of this cellulose was proposed to way to verify and compare the role of soil and PBAP as two be leaf litter generating fine particles from the biological separate sources of biologically derived PM is to compare decomposition process involving microorganisms and other the saccharide composition of source samples with the decomposers. Although atmospheric cellulose is not equiva- profiles representing locally important sources resolved by lent to atmospheric saccharides, the same process could receptor modeling based on ambient PM data matrix. The explain the enrichment of saccharides in fine aerosols. profiles derived from ambient PM data used for comparison Alternatively, unfavorable weather conditions (i.e., lower in this study are the nonlevoglucosan saccharide rich factors temperatures, air stagnation, low relative humidity) between resolved by a PMF model using the ambient PM speciation January and April may have prevented the fragmentation of data at Higley (16). These two source factors are labeled here coarse soil and PBAP particles and subsequent resuspension as “sucrose and trehalose rich bio-aerosol” and “glucose and into the atmosphere. Size distribution of saccharides in sugar polyol rich bio-aerosol”, respectively. aerosols has been previously reported to vary by season Initial comparison between the two ambient PM derived (46, 47). In short, a larger fraction of nonlevoglucosan source factors and the saccharide composition of the size- saccharides in ambient PM2.5 compared to PM10 at Higley fractionated soil samples (Figure 1) shows moderate con- was not expected, and could not be explained by a com- sistency. However, a major discrepancy is found in the relative parison with the size-fractionated local soil and PBAP samples abundance of sucrose, and to a lesser extent glucose. and the current knowledge of these source particles being Specifically, the sucrose content in the ambient PM derived associated primarily with coarse fraction of ambient PM. “sucrose and trehalose rich bio-aerosol” factor is greater than This suggests the contributions in the fine size fraction from 600 ng mg-1 for both PM10 and PM2.5, compared to less the biologically derived PM sources may be greater than than 20 ng mg-1 in the measured size-fractionated Higley previously acknowledged (10), and more research is needed soil samples. Similarly, the glucose content in the ambient to understand the atmospheric processing of particles from PM derived “glucose and sugar polyol rich bio-aerosol” factor primary biologic sources after they are released into the is around 140 ng mg-1 for PM2.5, and this is to compare with atmosphere and contribute to different size fractions of less than 25 ng mg-1 in the PM2.5 fraction of Higley soil ambient PM. samples. This discrepancy, consistent with the earlier

934 9 ENVIRONMENTAL SCIENCE & TECHNOLOGY / VOL. 45, NO. 3, 2011 conclusion based on the comparison between the saccharide of saccharide compounds in soil, plant, and spore samples. composition of Higley soil and the ambient PM samples, This material is available free of charge via the Internet at implies that resuspension of local soil was not solely http://pubs.acs.org. responsible for the measured saccharide rich source factors resolved by PMF for ambient PM collected at Higley. Literature Cited Alternatively, an equivalent comparison between the two ambient PM derived source factors and the saccharide (1) Simoneit, B. R. T. Biomass burning - A review of organic tracers composition of the size-fractionated plant and spore samples for smoke from incomplete combustion. Appl. Geochem. 2002, (Figure 2) shows the measured saccharide composition of 17 (3), 129–162. - (2) Simoneit, B. R. T.; Elias, V. O.; Kobayashi, M.; Kawamura, K.; these PBAP samples as 2 3 orders of magnitude higher when Rushdi, A. I.; Medeiros, P. M.; Rogge, W. F.; Didyk, B. M. Sugars compared to the ambient PM derived source factors. - Dominant water-soluble organic compounds in soils and However, the relative abundance of each saccharide species characterization as tracers in atmospheric particulate matter. in the plant samples is fairly consistent with the ambient PM Environ. Sci. Technol. 2004, 38 (22), 5939–5949. derived “sucrose and trehalose rich bio-aerosol” source factor. (3) Rogge, W. F.; Medeiros, P. M.; Simoneit, B. R. T. Organic marker In particular, Prosopis juliflora has a similar distribution of compounds for surface soil and fugitive dust from open lot dairies and cattle feedlots. Atmos. Environ. 2006, 40 (1), 27–49. nonlevoglucosan saccharides as the ambient PM derived (4) Rogge, W. F.; Medeiros, P. M.; Simoneit, B. R. T. Organic marker source factor. On the other hand, the saccharide profiles of compounds in surface soils of crop fields from the San Joaquin the collected spore samples are not consistent with the Valley fugitive dust characterization study. Atmos. Environ. 2007, ambient PM derived “glucose and sugar polyol rich bio- 41 (37), 8183–8204. aerosol” factor when comparing the relative abundance of (5) Graham, B.; Guyon, P.; Taylor, P. E.; Artaxo, P.; Maenhaut, W.; major saccharide compounds. This may be due to the small Glovsky, M. M.; Flagan, R. C.; Andreae, M. O. Organic com- pounds present in the natural Amazonian aerosol: Character- number of spore samples analyzed, and mature spores of ization by gas chromatography-mass spectrometry. J. Geophys. other common fungal species may significantly differ from Res.-Atmos. 2003, 108, D24. those analyzed in terms of their saccharide composition. For (6) Caseiro, A.; Marr, I. L.; Claeys, M.; Kasper-Giebl, A.; Puxbaum, example, S. rugosaannulata and L. edodes are enriched in H.; Pio, C. A. Determination of saccharides in atmospheric arabitol (23% and 28% of total saccharides) and P. ostreatus aerosol using anion-exchange high-performance liquid chro- spores are rich in sucrose (10% of total saccharides) when matography and pulsed-amperometric detection. J. Chromatogr. A 2007, 1171 (1-2), 37–45. compared to the composition of other fungal spore species (7) Elbert, W.; Taylor, P. E.; Andreae, M. O.; Poschl, U. Contribution (48). Nevertheless, all saccharide species in the ambient PM of fungi to primary biogenic aerosols in the atmosphere: wet derived “glucose and sugar polyol rich bio-aerosol” factor and dry discharged spores, carbohydrates, and inorganic ions. are present at significantly higher concentrations in the Atmos. Chem. Phys. 2007, 7 (17), 4569–4588. measured spore samples, supporting the likelihood that (8) NARSTO. Particulate Matter Science for Policy Makers - A entrainment of spores is one potential source influencing NARSTO Assessment; Cambridge University Press: Cambridge, UK, 2004; p 510. the chemical composition of this ambient PM derived source (9) Penner, J. E.; Andreae, M. O.; Annegarn, H.; Barrie, L.; et al. factor. Aerosols, their direct and indirect effects. In Climate Change In summary, the saccharide levels in two ambient PM 2001: The Scientific Basis. Contribution of Working Group I to derived source factors dominated by nonlevoglucosan sac- the Third Assessment Report of the Intergovernmental Panel on charides for Higley PM2.5 and PM10 were greater than those Climate Change; Houghton, J. T., et al., Eds.; Cambridge - in the measured size-segregated local soil samples, but less University Press: Cambridge, UK, 2001; pp 289 348. (10) Jaenicke, R. Abundance of cellular material and proteins in the than the measured saccharides in size-segregated PBAP atmosphere. Science 2005, 308 (5718), 73–73. samples. This indicates the ambient PM derived source (11) Simoneit, B. R. T.; Schauer, J. J.; Nolte, C. G.; Oros, D. R.; Elias, factors could only be explained as representing a combination V. O.; Fraser, M. P.; Rogge, W. F.; Cass, G. R. Levoglucosan, a of both PBAPs which were measured to have higher levels tracer for cellulose in biomass burning and atmospheric of saccharides and soil and associated biota which were particles. Atmos. Environ. 1999, 33 (2), 173–182. measured to have lower levels of saccharides. Alternatively, (12) Fraser, M. P.; Lakshmanan, K. Using levoglucosan as a molecular marker for the long-range transport of biomass combustion the saccharide-enriched PBAPs may have undergone some aerosols. Environ. Sci. Technol. 2000, 34 (21), 4560–4564. physical transformation (i.e., resuspension, wetting, drying) (13) Hoffmann, D.; Tilgner, A.; Iinuma, Y.; Herrmann, H. 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