Health Effects and Energy Choices

ABSTRACT

Day- and nighttime total suspended particulate matter was collected inside and outside Emperor Qin's Terra-Cotta Museum in winter and summer 2008. The purpose was to characterize the winter and summer differences of indoor airborne particles in two display halls with different architectural and ventilation conditions, namely the Exhibition Hall and Pit No. 1. The morphology and elemental composition of two season samples were investigated using scanning electron microscopy and energy dispersive X-ray spectrometry. It is found that the particle size, particle mass concentration, and particle type were associated with the visitor numbers in the Exhibition Hall and with the natural ventilation in Pit No. 1 in both winter and summer. Evident winter and summer changes in the composition and physicochemical properties of the indoor suspended particulate matters were related to the source emission and the meteorological conditions. Particle mass concentrations in both halls were higher in winter than in summer. In winter, the size of the most abundant particles at the three sites were all between 0.5 and 1.0 μm, whereas in summer the peaks were all located at less than 0.5 μm. The fraction of sulfur-containing particles was 2–7 times higher in winter than in summer. In addition to the potential soiling hazard, the formation and deposition of sulfur-containing particles in winter may lead to the chemical and physical weathering of the surfaces of the terra-cotta statues.

IMPLICATIONS Relatively few microanalyses of indoor airborne particles inside museums in China have been performed. The mass concentrations of winter and summer indoor total suspended particulate (TSP) are presented for the Emperor Qin's Terra-Cotta Museum along with the characterization of individual particles via computerized scanning electron microscopy and an energy dispersive X-ray spectrometry. The results indicate that both the high level of particle mass concentrations in winter and the predominant fine particles in summer were responsible for the soiling of the statues over a long period of time. The irreplaceable statues were also facing with weathering hazards posed by abundant sulfur-containing particles, especially in winter. Data provided in this study suggested that mechanical ventilation, air filtration, and air conditioning systems should be installed in Pit No. 1 display hall and proper display strategy should be adopted in Exhibition Hall.     

Winter and summer characteristics of airborne particles inside emperor Qin's Terra-Cotta Museum, China: a study by scanning electron microscopy-energy dispersive X-ray spectrometry

Day- and nighttime total suspended particulate matter was collected inside and outside Emperor Qin's Terra-Cotta Museum in winter and summer 2008. The purpose was to characterize the winter and summer differences of indoor airborne particles in two display halls with different architectural and ventilation conditions, namely the Exhibition Hall and Pit No. 1. The morphology and elemental composition of two season samples were investigated using scanning electron microscopy and energy dispersive X-ray spectrometry. It is found that the particle size, particle mass concentration, and particle type were associated with the visitor numbers in the Exhibition Hall and with the natural ventilation in Pit No. 1 in both winter and summer. Evident winter and summer changes in the composition and physicochemical properties of the indoor suspended particulate matters were related to the source emission and the meteorological conditions. Particle mass concentrations in both halls were higher in winter than in summer. In winter, the size of the most abundant particles at the three sites were all between 0.5 and 1.0 microm, whereas in summer the peaks were all located at less than 0.5 microm. The fraction of sulfur-containing particles was 2-7 times higher in winter than in summer. In addition to the potential soiling hazard, the formation and deposition of sulfur-containing particles in winter may lead to the chemical and physical weathering of the surfaces of the terra-cotta statues.     

Qualitative evaluation of the mineralogical and chemical composition of dry deposition in the central and southern highlands of Jordan

The chemical and mineralogical composition of dry deposition in the western highlands of central and south Jordan at the end of the summer season 2000, reflect the composition of soils in addition to anthropogenic activities at these areas. Calcite predominated in the central region whereas calcite and quartz are the dominant minerals in south Jordan. The concentrations of Hg, Cr, Ni, Cu, Pb and Zn were higher in central Jordan, which might be attributed to higher anthropogenic activities than south. On the other hand, Fe, Mn, Ti, Ba, Sr, Y and Rb were higher in the south of Jordan reflecting the composition of soil at these sites. At Aqaba city, the only port of Jordan, where Cr, Cd, As and S were higher than other areas. This variation might be attributed to the contribution of phosphate dust in the atmosphere through handling processes.     

Seasonal and spatial differences in mass concentration levels and particle size distribution of aerosols over an urban area

Data on mass concentration levels and particle size distribution based on samples simultaneously collected at three different areas of a city in winter and in summer were analysed and compared. In summer concentrations were consistent at all three sites, while in winter significantly higher concentrations were recorded in a densely populated city centre with traditional space heating. The investigated correlations and regression equations indicate that the city centre acts as a major source of particulate pollution in the winter time and that it influences air pollution in other parts of the town, especially in the south in the direction of prevalent NE winds. All concentration levels were within the limits established by Whitby and Liu in American cities.The particle size distribution was bimodal and very consistent for the three sites but there was a significant shift towards smaller particles in winter.     

Influence of atmospheric dispersion and new particle formation events on ambient particle number concentration in Rochester, United States, and Toronto, Canada

Continuous measurements of particle number concentrations were performed in Rochester, NY, and Toronto, Ontario, Canada during the 2003 calendar year. Strong seasonal dependency in particle number concentration was observed at two sites. The average number concentration of ambient particles was 9670 +/- 6960 cm(-3) in Rochester, whereas in Toronto the average number of particles was 28,010 +/- 13,350 cm(-3). The particle number concentrations were higher in winter months than in summer months by a factor of 1.5 in Rochester and 1.6 in Toronto. In general, there were also distinct diurnal variations of aerosol number concentration. The highest weekdays/weekends ratio of number concentration was typically observed during the rush-hour period in winter months with a ratio of 2.1 in Rochester and 2.0 in Toronto. The correlation in the total particle number concentrations between the two urban sites was stronger in winter because of the common urban traffic patterns, but weaker in summer because of local sulfur dioxide (SO2)-related particle formation events in Rochester in the summer. Strong morning particle formation events were frequently observed during colder winter months. Good correlations between particle number and carbon monoxide (CO) as well as temperature suggested that motorvehicle emissions lead to the formation of new particles as the exhaust mixes with the cold air. Regional nucleation and growth events frequently occurred in April. Local SO2-related particle formation events most frequently occurred in August. SO2 and UV-B were highly correlated with particle concentration, suggesting a high association of photochemical processes with these local events. A high directionality in a northerly direction was observed for particle number and SO2, indicating the influence of point sources located north of Rochester.     

Chemical composition and complex refractive index of Saharan Mineral Dust at Izaña,Tenerife (Spain) derived by electron microscopy

Samples from two strong homogeneous dust plumes from the Saharan desert reaching Izaña (Tenerife, Spain) in July and August 2005 were taken with a miniature impactor system and filter samplers. Size, aspect ratio and chemical composition of more than 22,000 individual particles were studied by scanning electron microscopy. The mineralogical phase composition of about 200 particles was investigated by transmission electron microscopy. In addition, the aerosol size distribution was measured with an optical particle spectrometer. In all samples, the aerosol was dominated by mineral dust with an average composition (by volume) of 64% silicates, 6% quartz, 5% calcium-rich particles, 14% sulfates, 1% hematite, 1% soot and 9% other carbonaceous material. Sulfate was found predominantly as coating on other particles with an average thickness of approximately 60 nm. The aerosol calcium content is correlated with the calcite concentrations of soils in the source region, highest values were observed for northern and central Algeria and Morocco. The average aspect ratio of the particles was 1.64. The distributions of the aspect ratios are parameterized by log-normal functions for modeling purpose. Single-scattering albedo (0.95) and asymmetry factor (0.74–0.81) was measured by polar aerosol photometry on filter samples using a light source resembling the solar spectrum. The apparent soot content of the sample (1 vol%) was determined by the same technique. From the mineralogical data, an average complex refractive index of 1.59–9×10⁻³i for visible light was derived. The imaginary part of the complex refractive index decreases with increasing particle size from −2.5×10⁻²i to <−10⁻³i, reflecting the decreasing hematite and soot contents. The imaginary part derived from optical measurements was −7×10⁻³i.     

Estimates of Particle Hygroscopicity during the Southeastern Aerosol and Visibility Study

ABSTRACT

Aerosol water content was determined from relative humidity controlled optical particle counter (ASASP-X) size distribution measurements made during the Southeastern Aerosol and Visibility Study (SEAVS) in the Great Smoky Mountains National Park during summer 1995. Since the scattering response function of the ASASP-X is sensitive to particle refractive index, a technique for calibrating the ASASP-X for any real refractive index was developed. A new iterative process was employed to calculate water mass concentration and wet refractive index as functions of relative humidity. Experimental water mass concentrations were compared to theoretically predicted values assuming only ammonium sulfate compounds were hygroscopic. These comparisons agreed within experimental uncertainty. Estimates of particle hygroscopicity using a rural aerosol model of refractive index as a function of relative humidity demonstrated no significant differences from those made with daily varying refractive index estimates. Although aerosol size parameters were affected by the assumed chemical composition, forming ratios of these parameters nearly canceled these effects.     

Atmospheric particle size distributions of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and polycyclic aromatic hydrocarbons (PAHs) and their implications for wet and dry deposition

Concurrent measurements of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and polycyclic aromatic hydrocarbons (PAHs) in different size fractions of atmospheric particulate matter are presented for a winter and a summer sampling period. The PCDD/Fs and PAHs were primarily associated with particles of <1.35 μm aerodynamic diameter. The particle size distributions were similar for the compounds within each substance group and, surprisingly, also between the PCDD/Fs and PAHs. Changes in the particle size distribution of particle mass were reflected in the particle size distributions of the PCDD/Fs and PAHs.The data were employed to identify those particle size fractions dominating the wet and dry particle bound deposition of PCDD/Fs and PAHs and, furthermore, to assess the relative contributions of wet and dry deposition to the total particle bound deposition fluxes. The calculations indicate that coarse particles contribute most to the dry deposition while, in contrast, the wet deposition of the PCDD/Fs and PAHs is dominated by fine particles. Furthermore, it is estimated that in Bayreuth wet deposition dominates the total particle bound deposition of PCDD/Fs and PAHs.     

Mineralogical and chemical characterization of suspended atmospheric particles over the east Mediterranean based on synoptic-scale circulation patterns

Suspended atmospheric particles were collected in Israel in order to identify their nature and relationships with the major synoptic-scale circulation patterns. The particles were analyzed for their major and trace element concentrations and mineralogical composition. Samples were collected during three synoptic systems associated with desert dust storms: Red Sea trough, Sharav cyclone and cold depression, and during deep and shallow modes of Persian Gulf trough, which prevails in the summer months and is not associated with dust storms.All samples mostly contain particles smaller than 2 μm. The suspended desert dust is composed primarily of illite–smectite and calcite. Some indicative secondary minerals were found for each of the dust transporting synoptic systems (e.g., palygorskite for Red Sea trough). The bulk chemistry data support the mineralogical observations and reveal additional chemical signatures of each dust transporting system. For instance, Red Sea trough samples have significantly higher Ca/Al and Ca/Mg in the carbonate and Mg/Al in Al-silicate fraction than cold depression samples. Nevertheless, Sharav cyclone samples have intermediate values in spite of the fact that the source of the dust during these conditions is similar to cold depression (i.e., North Africa). Even though differences in the chemical and the mineralogical composition of desert dust do exist, this study reveals their overall chemical and mineralogical similarities.In contrast to the synoptic systems that carry desert dust, the inorganic fraction of the Persian Gulf trough samples contains significant amount (up to 50%) of non-mineral material that has a pronounced chemical signature in terms of major element concentrations (e.g., Al, Ca, Mg, Na, S) implying their anthropogenic nature, probably from countries around the Black Sea. This striking finding is indicative for atmospheric pollution in the Eastern Mediterranean region during the summer.     

Enrichment of trace elements in the clay size fraction of mining soils

Reactive waste dumps with sulfide minerals promote acid mine drainage (AMD), which results in water and soil contamination by metals and metalloids. In these systems, contamination is regulated by many factors, such as mineralogical composition of soil and the presence of sorption sites on specific mineral phases. So, the present study dedicates itself to understanding the distribution of trace elements in different size fractions (<2-mm and <2-μm fractions) of mining soils and to evaluate the relationship between chemical and mineralogical composition. Cerdeirinha and Penedono, located in Portugal, were the waste dumps under study. The results revealed that the two waste dumps have high degree of contamination by metals and arsenic and that these elements are concentrated in the clay size fraction. Hence, the higher degree of contamination by toxic elements, especially arsenic in Penedono as well as the role of clay minerals, jarosite, and goethite in retaining trace elements has management implications. Such information must be carefully thought in the rehabilitation projects to be planned for both waste dumps.     

Size distribution and diurnal and seasonal trends of ultrafine particles in source and receptor sites of the Los Angeles basin

This paper presents results from a study conducted in two urban areas of southern California, Downey and Riverside, to examine the effect of different sources and formation mechanisms on the size distribution and temporal trends of ultrafine particles. Near-continuous data were collected for 5 months at each location. Our data clearly identified Downey as a source site, primarily affected by vehicular emissions from nearby freeways, and Riverside as a receptor site, where photochemical secondary reactions form a substantial fraction of particles, along with local vehicular emissions. In Downey, the diurnal trends of total particle number concentration and elemental carbon (EC) appear to be almost identical throughout the day and irrespective of season, thereby corroborating the role of primary emissions in the formation of these particles. This agreement between EC and particle number was not observed in Riverside during the warmer months of the year, while very similar trends to Downey were observed during the winter months in that area. Similarly, the size distribution of ultrafine particles in Downey was generally unimodal with a mode diameter of 30-40 nm and without significant monthly variations. The number-based particle size distributions obtained in Riverside were bimodal, with a significant increase in accumulation mode as the season progressed from winter to summer. During the warmer months, there was also an increase in sub-100-nm particles in the afternoon hours, between 2:00 p.m. and 4:00 p.m., that also increased with the temperature. The differences observed in the ultrafine particle distribution and temporal trends clearly demonstrated that mechanisms other than direct emissions play an important role in the formation of ultrafine particles in receptor sites of the Los Angeles Basin.     

Aircraft measurements of air pollution in the norwegian arctic

Physical properties, particle size distribution and chemical composition of the Arctic aerosol aloft have been studied to assess the origin of polluted layers of the Arctic air. Four measurement campaigns were made with the NILU aircraft during the period March 1983–JuIy 1984. Evidence of very long range transport of air masses to the Arctic is presented for summer and winter conditions. These polluted air masses are observed at higher altitudes (> 1.5 km). The layers of polluted air at lower altitudes are believed to be due to episodes of air mass transport from emission areas with a temperature similar to that in the Arctic in winter, and from local sources in summer. However, further aircraft measurements are needed to support these preliminary results.     

Mineral particles content in recent snow at Summit (Greenland)

The mineral insoluble fraction of snowpit samples collected at Summit is investigated, representing deposition from summer 1987 to summer 1991. We attempt to describe the particles which are observed in the series, with very large seasonal variations. Elemental, mineralogical and size distribution studies are carried out on four samples selected according to the chemical profile of the snowpit (two samples from spring and two from winter) using X-ray fluorescence spectrometry and analytical transmission electron microscopy. Results indicate a large predominance of the soil-derived particles originating from arid or semi-arid regions of the Northern Hemisphere. The mineralogy clearly indicates a high contribution for the muscovite-illite associated with a low kaolinite/chlorite ratio, together with the rather lack of smectite. This supports the hypothesis of an Asian source. Several other factors are consistent with this Asian source, like the recent climatology and the good timing between the Asian dust storms period and the peak of dust concentration in the ice. The mineralogy of the insoluble particles in the snow is similar between winter and spring, suggesting that the change of concentration between the seasons is more strongly linked to changes of atmospheric parameters than changes of the source regions.     

Comparative assessment of air quality in two health resorts using carbon isotopes and palynological analyses

This paper describes results of applying the palynological and carbon isotopic analysis of the organic fraction of Total Suspended Particles (TSP) to discriminate distinct pollution sources and assess the anthropogenic impact for the investigated areas. The samples of atmospheric particles were collected in Czerniawa and Cieplice (two health resorts in Lower Silesia, SW Poland) twice a year in summer and winter season (from July 2006 to February 2008). The palynological spectra represent in the vast majority local plant communities without a noticeable contribution of long-transported plant particles. Palynological analysis revealed also differences in the specificity of the two sampling areas, i.e. the higher contribution of identified organic material in Czerniawa stands for more natural character of this site, but is also responsible for the higher allergic pressure when compared to Cieplice. The carbon isotopic composition of TSP varied seasonally (δ¹³C value from ?27.09‰ in summer to ?25.47‰ in winter). The increased δ¹³C value in winter (heating period) is most probably caused by uncontrolled contribution of coal soot. On the basis of isotopic mass balance the calculated contribution of anthropogenic organic particles in the atmosphere reached in winter season 72% in Czerniawa and 79% in Cieplice.     

Influence of seasons,air mass origin and day of the week on size-segregated chemical composition of aerosol particles at a kerbside

The size-segregated chemical composition of atmospheric aerosol particles (aerodynamic diameter Dp_aer = 0.05–10 μm) was studied to reveal differences between seasons (winter/summer), air mass origins (East/West/North), and days of the week (weekday/Sunday). The goal was to identify the different particle emission sources for the first time at a kerbside in the city of Dresden, Germany.Ultra-fine particles (Dp_aer = 0.05–0.14 μm, 12% of PM₁₀) consisted of approximately 80% OM (organic matter) and EC (elemental carbon), while fine particles (Dp_aer = 0.14–1.2 μm) comprised about 55% ionic compounds with 44% OM and EC. The coarse fraction (Dp_aer = 1.2–10 μm) consisted of approximately 65% ions/OM/EC and 20% metal oxides.Pb, Zn, and Cu showed crustal enrichment factors (CEF_Si) > 100 for all particle sizes indicating strong anthropogenic influence. The Zn source was coal burning rather than traffic emissions. Doubled concentrations in winter were likely caused by coal combustion (Pb) and biomass burning (K), but also by a lower mixing layer height. Air masses from the East caused higher Pb and K concentrations. The origin of air masses had almost no influence on Cu, Cr, Fe, Mn, Zn and Ca, Si, Ti, indicating local sources such as traffic and heating. Possible actions against particle emissions are discussed.     

Analysis of organic and inorganic species on the surface of atmospheric aerosol using time-of-flight secondary ion mass spectrometry (TOF-SIMS)

This work explores the utility of time-of-flight static secondary-ion mass spectrometry (TOF-SIMS) for the analysis of the surface organic layer on individual atmospheric aerosol particles. The surface sensitivity and minimal fragmentation available with TOF-SIMS suggest that it can be a powerful tool for the examination of the organic and inorganic species on the surface of individual particles. Cascade impactors were used to collect aerosol from summer 2000 Montana forest fires, winter snowmobile samples in Yellowstone National Park, Hawaiian lava and sea salt, from an Asian Dust event reaching Salt Lake City, Utah in April 2001 and from Salt Lake Valley summer urban aerosol. TOF-SIMS analysis and multivariate statistical techniques combined gave chemical and morphological information about the particles. Surfaces of the aerosol from forest fires, snowmobile exhaust, and sea salt were all dominated by aliphatic hydrocarbons and their amphiphilic derivatives. Each source showed a different organic chemical signature. The extent and composition of the organics layer which typically covers the surface of atmospheric particles are expected to effect all of the surface related aerosol properties such as health effects, the ability of the particle to activate and form cloud droplets, and the aggregation of particles as well as reactions between the particle and gas phase species.     

Source characterization of fine and coarse particles at the East Mediterranean coast

Fine and coarse atmospheric particles were collected in Ashdod—a midsize industrial city on the southeastern Mediterranean coast, and in Gedera—a rural site, to characterize ambient particles and to determine their long-range transport during two major seasons—winter and summer. Manual PM2.5 and PM10 samplers, dichotomous samplers, continuous automated PM10 samplers, and denuders were used to sample particulate and gaseous pollutants.Fine and coarse concentrations in Ashdod were 21.2 and 39.6 μg m⁻³, and 23.9 and 30.5 μg m⁻³ in the fall–winter and summer campaigns, respectively. Crustal material, as calcites or dolomites mixed with silicates, dominated the coarse fraction and also the fine fraction on dusty days. In the fall–winter, S, P, and Ni were coupled with minerals. Coarse Ni was associated with crustal material during dust storms, while P originated from shipping and deposition of phosphates in the urban area around.Sulfates dominated the fine fractions in the summer season averaging 12 μg m⁻³. Multivariate analysis indicated that S was associated with As and Se, V and Ni, both associated with heavy fuel combustion, and Zn and Pb. In winter, those mixed sources were local, but in summer they were part of long-range transport. In the fall–winter, Zn and Pb were strongly associated with Mn, Ga, and Cu—elements emitted from either traffic or metal processing plants.Although the influence of crustal material on both size fractions was significant, most heavy metals were associated with PM2.5. Higher concentrations were linked to a larger number of particles in this fraction, to a larger surface area available for biochemical reaction [Harrison, R., Shi, J., Xi, S., Khan, A., Mark, D., Kinnersley, R., Yin, J., Philos, T., 2000. Measurement of number, mass and size distribution of particles in the atmosphere. Philosophical Transactions of the Royal Society 358, 2567–2579], and finally to a larger concern in regards to health effects.     

Elk River Completes Second Year With Zero Bag Failures Reported

Abstract

This paper presents results from a study conducted in two urban areas of southern California, Downey and Riverside, to examine the effect of different sources and formation mechanisms on the size distribution and temporal trends of ultrafine particles. Near-continuous data were collected for 5 months at each location. Our data clearly identified Downey as a source site, primarily affected by vehicular emissions from nearby freeways, and Riverside as a receptor site, where photochemical secondary reactions form a substantial fraction of particles, along with local vehicular emissions. In Downey, the diurnal trends of total particle number concentration and elemental carbon (EC) appear to be almost identical throughout the day and irrespective of season, thereby corroborating the role of primary emissions in the formation of these particles. This agreement between EC and particle number was not observed in Riverside during the warmer months of the year, while very similar trends to Downey were observed during the winter months in that area. Similarly, the size distribution of ultrafine particles in Downey was generally unimodal with a mode diameter of 30–40 nm and without significant monthly variations. The number-based particle size distributions obtained in Riverside were bimodal, with a significant increase in accumulation mode as the season progressed from winter to summer. During the warmer months, there was also an increase in sub-100-nm particles in the afternoon hours, between 2:00 p.m. and 4:00 p.m., that also increased with the temperature. The differences observed in the ultrafine particle distribution and temporal trends clearly demonstrated that mechanisms other than direct emissions play an important role in the formation of ultrafine particles in receptor sites of the Los Angeles Basin.     

Characterization of polychlorinated dibenzo-p-dioxins and dibenzofurans in different particle size fractions of marine sediments

The distribution of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) was examined according to particle size in marine sediments, with a particular focus on fine particulates. Samples from different coastal sites were fractionated into five size groups (<2, 2-5, 5-10, 10-20, and 20-63 microm diameter) by gravitational split-flow thin fractionation. Despite the different size profiles and PCDD/F contents of the sediments at each site, PCDD/F levels in fractionations tended to increase as the particle size decreased; the PCDD/F levels in the finest particles were up to 16 times higher than in the coarsest particles, which was associated with their organic carbon contents. Log normalization showed high levels of PCDD/Fs in the fine silt particles (2-10 microm), which are consumable by aquatic biota. Because of the different toxicity and bioavailability of PCDD/Fs in different sediment particle sizes, it is important to study particle actions to understand their effects on the aquatic ecosystem.     

Simultaneous measurement of light-scattering properties and particle size distribution for aerosols: Application to ammonium sulfate and quartz aerosol particles

An apparatus for measuring the scattering phase function and linear polarization of aerosol particles has been developed. The apparatus uses an elliptical mirror and CCD camera to image the full angular scattering range simultaneously. An in-line aerodynamic particle sizer (APS) in the particle flow stream provides for the simultaneous measurement of the aerosol particle size distribution. This apparatus allows for a comparison of measured optical properties with theoretical model calculations based on the measured aerosol size distribution. The system was calibrated and tested using monodisperse polystyrene latex (PSL) spheres and with ammonium sulfate (AS) aerosol. We have also used the apparatus for measuring the scattering phase function and linear polarization for light scattering from irregular quartz aerosol particles. Our results show that Mie theory substantially overestimates the backscattering cross-section for quartz particles in the size parameter range X∼2–4, in agreement with previous experimental work and theoretical modeling studies. We also present a normalized synthetic phase function for quartz dust aerosol in the accumulation mode size range (0.1–2.0 μm).