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PubMed2005

An assessment on variation of sulphur dioxide and particulate matter in Erzurum (Turkey).

Sulphur dioxide and PM10 levels are investigated in Erzurum during the periods of 1990-2000 heating season to assess air pollution level. For that reason, emissions of sulphur dioxide and particulate matter were calculated by using consumption of fuels and Turkish emission factors. These emission values were evaluated together with air pollution levels, which were measured at six stations in Erzurum atmosphere during 1990-2000 winter periods. Results reveal that in 1990-1994 heating period, there is an increasing trend in the emissions and air pollution levels over Erzurum, and the air quality limits were not met. The daily 24 h limit (short-term limit) was exceeded 127 days in 1992-1993 winter period. The reason for this increase was found to be the switching to use of low-quality fossil fuels instead of cleaner ones. Results also indicated that there was a considerable decrease in emissions of air pollutants and air pollution levels after 1995. This can be explained by the consumption of more high-quality fossil fuels. The correlation coefficient of SO2 with PM10 is obtained as r2 = 0.85, which is a high value supporting the idea that both pollutants are emitted from the same source.

Air Pollutants↗

PubMed2004

Inflammatory effects of coarse and fine particulate matter in relation to chemical and biological constituents.

There is conflicting evidence in the literature as to the predominant mechanism and also the compositional element(s) that drives the pulmonary inflammatory response of ambient particulate matter (PM). We have investigated the inflammogenic potential of coarse (2.5-10 microm) and fine (<2.5 microm) PM from both a rural and an industrial location in Germany, using bronchoalveolar lavage (BAL) of rat lungs 18 h post intratracheal instillation with PM. Irrespective of the sampling location, the coarse fraction of PM(10) but not its fine counterpart caused neutrophilic inflammation in rat lungs, in the absence of any severe pulmonary toxicity as indicated by the lack of an increase in lavage protein and lactate dehydrogenase levels. The rural sample of coarse PM also caused a significant increase in the tumor necrosis factor alpha (TNFalpha) content as well as glutathione depletion in the BAL fluid. The contrasting inflammatory responses of the different samples could not be explained by differences in the concentrations of soluble Fe, Cu, V, Ni, Cr, or Al or by the.OH generating capacities of the PM suspensions. However, the effects of the different PM samples were clearly associated with their endotoxin content, as well as their ability to induce interleukin (IL)-8 and TNFalpha from whole blood in vitro. In conclusion, on an equal mass basis, coarse but not fine PM samples from our sampling campaign induced an inflammatory reaction in the lung in the absence of gross cellular lung damage, following intratracheal instillation. Our data also indicate, in accordance with previous independent in vitro observations, that endotoxin or related contaminants may play a role in these in vivo effects.

Air Pollutants↗

PubMed2000

Particulate matter modeling in the Los Angeles basin using SAQM-AERO.

The SARMAP air quality model, enhanced with aerosol modeling capability, and its associated components were developed to understand causes of ozone (O3) and particulate matter exceedances in the San Joaquin Valley of California. In order for this modeling system to gain increasing acceptance and use in guiding air quality management, it is important to assess how transportable this modeling system is across geographic domains. We describe the first application of the modeling system outside the "home" domain for which it was developed and evaluated. We have chosen the August 27-28, 1987, intensive monitoring period of the Southern California Air Quality Study to evaluate the performance of the modeling system and to assess its sensitivity to emission control options. The predicted surface concentrations of O3 and other gas-phase species were spatially and temporally correlated with measured data. The fractional normalized absolute error was 0.32 to 0.36 for O3, and somewhat larger for other species. The fractional normalized bias for O3 on August 27 and 28, 1987, was 0.02 to 0.04. The simulated PM2.5 mass and constituent species concentrations reproduced the magnitude and variability of the observed daytime concentrations at most locations; however, nighttime PM2.5 concentrations were overpredicted by the model. The model's response to emission control options was consistent with other models of the same genre.

Air Pollutants↗

PubMed2005

Evaluation of multisectional and two-section particulate matter photochemical grid models in the Western United States.

Version 4.10s of the comprehensive air-quality model with extensions (CAMx) photochemical grid model has been developed, which includes two options for representing particulate matter (PM) size distribution: (1) a two-section representation that consists of fine (PM2.5) and coarse (PM2.5-10) modes that has no interactions between the sections and assumes all of the secondary PM is fine; and (2) a multisectional representation that divides the PM size distribution into N sections (e.g., N = 10) and simulates the mass transfer between sections because of coagulation, accumulation, evaporation, and other processes. The model was applied to Southern California using the two-section and multisection representation of PM size distribution, and we found that allowing secondary PM to grow into the coarse mode had a substantial effect on PM concentration estimates. CAMx was then applied to the Western United States for the 1996 annual period with a 36-km grid resolution using both the two-section and multisection PM representation. The Community Multiscale Air Quality (CMAQ) and Regional Modeling for Aerosol and Deposition (REMSAD) models were also applied to the 1996 annual period. Similar model performance was exhibited by the four models across the Interagency Monitoring of Protected Visual Environments (IMPROVE) and Clean Air Status and Trends Network monitoring networks. All four of the models exhibited fairly low annual bias for secondary PM sulfate and nitrate but with a winter overestimation and summer underestimation bias. The CAMx multisectional model estimated that coarse mode secondary sulfate and nitrate typically contribute <10% of the total sulfate and nitrate when averaged across the more rural IMPROVE monitoring network.

Air Pollutants, Occupational↗

PubMed2006

Estimating the frequency distributions of particulate matter and their metal elements in a temple.

Air quality inside Asian temples is typically poor because of the burning of incense. This study measured and analyzed concentrations of fine (PM2.5) and coarse (PM2.5-10) particulate matter and their metal elements inside a temple in central Taiwan. Experimental results showed that the concentrations of metals Cd, Ni, Pb, and Cr inside the temple were higher than those at rural, suburban, urban, and industrial areas in other studies. Three theoretical parent distributions (lognormal, Weibull, and gamma) were used to fit the measured data. The lognormal distribution was the most appropriate distribution for representing frequency distributions of PM10, PM2.5, and their metal elements. Furthermore, the central limit theorem, H-statistic-based scheme, and parametric and nonparametric bootstrap methods were used to estimate confidence intervals for mean pollutant concentrations. The estimated upper confidence limits (UCLs) of means between different methods were very consistent, because the sample coefficient of variation (CV) was < 1. When the sample CV was > 1, the UCL based on H-statistical method tended to overestimate the UCLs when compared with other methods. Confidence intervals for pollutant concentrations at different percentiles were evaluated using parametric and nonparametric bootstrap methods. The probabilities of pollutants exceeding a critical concentration were also calculated.

Air Pollutants↗

PubMed2006

Transport and dispersion during wintertime particulate matter episodes in the San Joaquin Valley, California.

Data analysis and modeling were performed to characterize the spatial and temporal variability of wintertime transport and dispersion processes and the impact of these processes on particulate matter (PM) concentrations in the California San Joaquin Valley (SJV). Radar wind profiler (RWP) and radio acoustic sounding system (RASS) data collected from 18 sites throughout Central California were used to estimate hourly mixing heights for a 3-month period and to create case studies of high-resolution diagnostic wind fields, which were used for trajectory and dispersion analyses. Data analyses show that PM episodes were characterized by an upper-level ridge of high pressure that generally produced light winds through the entire depth of the atmospheric boundary layer and low mixing heights compared with nonepisode days. Peak daytime mixing heights during episodes were -400 m above ground level (agl) compared with -800 m agl during nonepisodes. These episode/nonepisode differences were observed throughout the SJV. Dispersion modeling indicates that the range of influence of primary PM emitted in major population centers within the SJV ranged from -15 to 50 km. Trajectory analyses revealed that little intrabasin pollutant transport occurred among major population centers in the SJV; however, interbasin transport from the northern SJV and Sacramento regions into the San Francisco Bay Area (SFBA) was often observed. In addition, this analysis demonstrates the usefulness of integrating RWP/RASS measurements into data analyses and modeling to improve the understanding of meteorological processes that impact pollution, such as aloft transport and boundary layer evolution.

Air Pollutants↗

PubMed2005

Inhalation of concentrated particulate matter produces pulmonary inflammation and systemic biological effects in compromised rats.

Although significant progress has been made over the past few years, there is still debate on the causal fractions that are responsible for particulate matter (PM)-associated adverse health effects. A series of 1-d inhalation exposures to concentrated ambient particles (CAPs) were performed in compromised rats, focusing on pulmonary inflammation and changes in blood factors as biological outcomes. Studies were carried out in The Netherlands at an urban background location in Bilthoven, an industrialized location in the city of Utrecht, as well as at a location that is heavily dominated by freeway emissions. It was hypothesized that exposure to CAPs resulted in oxidative stress in the lung, producing a release of inflammatory mediators, which in turn can result in cardiovascular effects. Both spontaneously hypertensive rats and rats preexposed to ozone were studied. The effects were studied at 2d postexposure, focusing on pathology and cell proliferation, bronchoalveolar lavage fluid (BALF) analysis (including cytokines, biochemistry, cell differentials, cell viability and proliferation, and Clara-cell 16 protein), and blood analyses (fibrinogen, Clara-cell 16 protein, Von Willebrand factor, and cell differentials). Using CAPs exposures as a binary term, mild inflammation (increased numbers of neutrophils) and increased lung permeability (protein and albumin leakage in BALF) were evident. In addition, CAPs also produced increased fibrinogen concentrations in blood of spontaneously hypertensive rats. In conclusion, inhalation up to 3700 microg/m3 CAPs in the size range of 0.15-2.5 microm did induce statistically significant effects in the lung and blood, but the effects observed may not potentially be very biologically relevant. PM mass concentrations and lung permeability were weakly associated. This suggests that other PM metrics might be more appropriate.

Air Pollutants↗

PubMed2006

A case-crossover study of fine particulate matter air pollution and onset of congestive heart failure symptom exacerbation leading to hospitalization.

Persons with congestive heart failure may be susceptible to ambient air pollution. The authors evaluated the association between exposure to particulate matter with an aerodynamic diameter of <2.5 microm (PM2.5) and onset of symptom exacerbation leading to hospital admission in Baltimore, Maryland. They used a case-crossover design for 135 case events occurring among 125 persons with prevalent congestive heart failure who were admitted to a single hospital through the emergency department during 2002. The case period was assigned using three index times: 8-hour and 24-hour periods of symptom onset and date of hospital admission. Controlling for weather, the authors detected a modest relative increase in risk for cases defined by 8-hour symptom onset for an interquartile-range increase in PM2.5 at a 2-day lag (odds ratio=1.09, 95% confidence interval: 0.91, 1.30). A corresponding increase in risk was not observed when admission date was used to define the case period. A series of simulations based on study data indicated that the study had adequate statistical power to detect odds ratios of 1.2 or higher. Although overall findings were not statistically significant, the identification of case events defined by an 8-hour onset period may be more relevant than either a 24-hour onset period or the admission date for estimating harmful effects of air pollutant exposure on cardiovascular health.

Aged↗

PubMed2005

Acute cardiopulmonary alterations induced by fine particulate matter of São Paulo, Brazil.

The mechanisms involved in the association between air pollution and increased cardiovascular morbidity are not fully understood. The objective of this study was to test the hypothesis that fine particulate matter (PM(2.5)) induces systemic inflammation and vasoconstriction of small arteries in the lung and heart of rats. Thirty-eight healthy Wistar rats were anesthetized, intubated, and submitted to the instillation of 1 ml of distilled water diluted in the following solution: blank filter, 100 microg and 500 microg of PM(2.5). PM(2.5) was collected in glass fiber filters with a high-volume sampler. The animals were sacrificed 24 h after instillation when blood, heart, and lung samples were collected for morphological and wet-to-dry weight ratio analysis. PM(2.5) consisted of the following elements: sulphur, arsenic, bromine, chlorine, cobalt, iron, lanthanum, manganese, antimony, scandium, and thorium. Total reticulocytes significantly increased at both PM(2.5) doses (p < 0.05) while hematocrit levels increased in the 500 microg group (p < 0.05). Quantification of segmented neutrophils and fibrinogen levels showed a significant decrease, while lymphocytes counting increased with 100 microg of PM(2.5) (p < 0.05). A significant dose-dependent decrease of intra-acinar pulmonary arteriole lumen/wall ratio (L/W) was observed in PM groups (p < 0.001). Peribronchiolar arterioles L/W showed a significant decrease in the 500 microg group (p < 0.001). A significant increase in heart wet-to-dry weight ratio was observed in the 500 microg group (p < 0.001). In conclusion, fine environment particles in the city of São Paulo promote pulmonary and cardiac histological alterations. Pulmonary vasculature was markedly affected by particle instillation, resulting in significant vasoconstriction in healthy rats.

Administration, Inhalation↗

PubMed2000

Particulate matter in urban areas: health-based economic assessment.

The interest in the association between human health and air pollution has grown substantially in recent years. Based on epidemiological studies in several countries, there is conclusive evidence of a link between particulate air pollution and adverse health effects. Considering that particulate matter may be the most serious pollutant in urban areas and that pollution-related illness results in financial and non-financial welfare losses, the main objective of this study is to assess the economic benefits of reducing particulate air pollution in Lebanese urban areas. Accordingly, the extent and value of health benefits due to decreasing levels of particulate in the air are predicted. Health impacts are expressed in both physical and monetary terms for saved statistical lives, and productivity due to different types of morbidity endpoints. Finally, the study concludes with a range of policy options available to mitigate particulate air pollution in urban areas.

Air Pollution↗

PubMed2001

Particulate matter and daily mortality and hospital admissions in the west midlands conurbation of the United Kingdom: associations with fine and coarse particles, black smoke and sulphate.

OBJECTIVES: There is considerable evidence linking ambient particles measured as particulate matter with aerodynamic diameter <10 microm (PM(10)) to daily mortality and hospital admissions but it is not clear which physical or chemical components of the particle mixture are responsible. The relative effects of fine particles (PM(2.5)), coarse particles (PM(2.5-10)), black smoke (mainly fine particles of primary origin) and sulphate (mainly fine particles of secondary origin) were investigated, together with ozone, SO(2), NO(2), and CO, on daily mortality and hospital admissions in the west Midlands conurbation of the United Kingdom. METHODS: Time series of health outcome and environmental data were obtained for the period 1994-6. The relative risk of death or hospital admission was estimated with regression techniques, controlling for long term time trends, seasonal patterns, influenza epidemics, effects of day of the week, and temperature and humidity. Models were adjusted for any remaining residual serial correlation and overdispersion. The sensitivities of the estimates for the effects of pollution to the inclusion of a second pollutant and seasonal interactions (warm or cool) were also examined. RESULTS: Daily all cause mortality was not associated with any gaseous or particulate air pollutant in the all year analysis, although all measures of particles apart from PM(2.5-10) showed significant positive effects of the warm season. Neither respiratory nor cardiovascular admissions (all ages) were associated with any air pollutant, and there were no important seasonal interactions. However, analysis of admissions by age found evidence for various associations-notably between PM(10), PM(2.5), black smoke, SO(2,) and ozone (negative) and respiratory admissions in the 0-14 age group. The coarse fraction, PM(2.5-10) differed from PM(2.5) in having smaller and less consistent associations (including several large significant negative associations) and a different lag distribution. The results for black smoke, an indicator of fine primary carbonaceous particles, were very similar to those for PM(2.5), and tended to be more robust in two pollutant models. The effects of sulphate, an indicator of secondary particles, also showed some similarities to those of PM(2.5). CONCLUSIONS: Clear effects of air pollution on mortality and hospital admissions were difficult to discern except in certain age or diagnostic subgroups and seasonal analyses. It was also difficult to distinguish between different measures of particles. Within these limitations the results suggest that the active component of PM(10) resides mostly in the fine fraction and that this is due mainly to primary particles from combustion (mainly vehicle) sources with a contribution from secondary particles. Effects of the coarse fraction cannot be excluded.

Adolescent↗

PubMed2003

Pulmonary antioxidants exert differential protective effects against urban and industrial particulate matter.

This investigation focuses on the application of an in vitro assay in elucidating the role of lung lining fluid antioxidants in the protection against inhaled particles, and to compare the toxicities of different airborne particulate matter (PM), PM10, collections from South Wales, UK. PM collections from both urban and industrial sites caused 50% oxidative degradation of DNA in vitro at concentrations as low as 12.9 +/- 2.1 microg ml(-1) and 4.9 0.9 mg ml-1 respectively. The primary source of this bioreactivity was found to be the soluble fraction of both particle collections. The coarser PM(10-2.5) fraction also showed greater oxidative bioreactivity than the PM(2.5-0.1) in both cases. When repeated in the presence of a low molecular weight fraction of fresh pulmonary lavage fluid, as well as in artificial lung lining fluid (200 microM urate, glutathione and ascorbate), the DNA damage was significantly reduced in all cases (P < 0.05). The antioxidants exerted a greater effect on the industrial samples than on the urban samples, and on the PM(10-2.5) fractions than on the PM(2.5-0.1) fractions, supporting the previous findings that respirable PM and urban samples contain fewer free radical sources than inhalable PM and industrial samples.

Air Pollutants↗

PubMed2002

Sources of atmospheric carbonaceous particulate matter in Pittsburgh, Pennsylvania.

The organic carbon (OC)/elemental carbon (EC) tracer method is applied to the Pittsburgh, PA, area to estimate the contribution of secondary organic aerosol (SOA) to the monthly average concentration of organic particulate matter (PM) during 1995. An emissions inventory is constructed for the primary emissions of OC and EC in the area of interest. The ratio of primary emissions of OC to those of EC ranges between 2.4 in the winter months and 1.0 in the summer months. A mass balance model and ambient measurements were used to assess the accuracy of the emissions inventory. It is estimated to be accurate to within 50%. The results from this analysis show a strong monthly dependence of the SOA contribution to the total organic PM concentration, varying from near zero during winter months to as much as 50% of the total OC concentration in the summer.

Aerosols↗

PubMed2003

The impact of a building implosion on airborne particulate matter in an urban community.

In response to community concerns, the air quality impact of imploding a 22-story building in east Baltimore, MD, was studied. Time- and space-resolved concentrations of indoor and outdoor particulate matter (PM) (nominally 0.5-10 microm) were measured using a portable nephelometer at seven and four locations, respectively. PM10 levels varied in time and space; there was no measurable effect observed upwind of the implosion. The downwind peak PM10 levels varied with distance (54,000-589 microg/m3) exceeding pre-implosion levels for sites 100 and 1130 m 3000- and 20-fold, respectively. Estimated outdoor 24-hr integrated mass concentrations varied from 15 to 72 microg/m3. The implosion did not result in the U.S. Environmental Protection Agency (EPA) National Ambient Air Quality Standard (NAAQS) for PM10 being exceeded. X-ray fluorescence analysis indicated that the elemental composition was dominated by crustal elements: calcium (57%), silicon (23%), aluminum (7.6%), and iron (6.1%). Lead was above background but at a low level (0.17 microg/m3). Peak PM10 concentrations were short-lived; most sites returned to background within 15 min. No increase in indoor PM10 was observed even at the most proximate 250 m location. These results demonstrate that a building implosion can have a severe but short-lived impact on community air quality. Effective protection is offered by being indoors or upwind.

Air Pollutants↗

PubMed1975

Particulate matter in reconstituted amphotericin B and assay of filtered solutions of amphotericin B.

Amphotericin B colloidal solutions were prepared according to the manufacturer's directions and filtered with membrane filters of different porosity to test for particulate matter; and the concentration and in vitro microbiological activity of filtered and nonfiltered solutions were determined. The amphotericin B solutions contained numerous particles. Filtration through 0.85- and 0.45-mum filters did not reduce the in vitro antimicrobial activity, and filtration through 5-, 0.45-, and 0.22-mum filters did not alter the concentration of the drug when assayed spectrophotometrically.

Amphotericin B↗

PubMedDate not supplied

Liquid chromatographic determination of benzo[a]pyrene in total particulate matter of cigarette smoke.

The benzo[a]pyrene (BaP) delivery of reference and commercially available tobacco cigarettes, as well as reference and placebo marijuana cigarettes, is determined using a sequential liquid chromatographic/liquid chromatographic procedure. The total particulate matter of sample cigarette smoke is collected using a Cambridge filter pad, which is ultrasonically extracted with acetone. The resulting extract is filtered, then fractionated using semipreparative-scale normal phase liquid chromatography (LC). Quantitative determination is achieved using analytical-scale reverse phase LC equipped with a fluorescence detector. The method is precise (+/- 10-15% relative standard deviation) and yields 85% or better BaP recovery at the ng/cig. level. A single pad may be analyzed in 8 person-hours, while a more typical lot of 12 pads (6 pads each for 2 cigarette brands) may be analyzed in 10 person-days.

Benzo(a)pyrene↗

PubMed1972

The size of suspended particulate matter in air.

By means of the NASN cascade impactor the particle sizes of ambient aerosols can be measured by fractionating the particles according to their aerodynamic dimensions, and the fractions can be quantified gravimetrically. Data obtained with this instrument show that particulate matter suspended in urban air in the United States and Great Britain is remarkably uniform in distribution and that the particles are predominantly less than 1 microm in diameter. In Ankara, Turkey, the high proportion of particles larger than 1 microm in diameter are associated with the incomplete combustion of lignite; particulate concentrations in Ankara, however, are considerably higher than those measured elsewhere. The growth of particles in air during temperature inversions occurs in Cincinnati; the greater proportion of large particles found there during inversion periods can account for the reduction in visibility. Aerosols in the vicinity of highways are composed of particles larger than those found some distance away because of the reentrainment of debris by the traffic-induced turbulence. On the other hand, highway configuration and traffic volume have little effect on the size distribution of aerosols in samples collected away from the turbulence area of the roadway. Aerosols measured inside buildings are predominantly smaller in size and exhibit a narrower range of sizes than aerosols outside buildings.

Aerosols↗

PubMed2004

Pulmonary retention of particulate matter is associated with airway inflammation in allergic rats exposed to air pollution in urban Detroit.

A collaborative research study was conducted in order to improve our understanding of the source-to-receptor pathway for ambient fine particulate matter (aerodynamic diameter < or = 2.5 mu m; PM2.5) and subsequently to investigate the identity and sources of toxic components in PM2.5 responsible for adverse health effects in allergic humans. This research used a Harvard fine particle concentrator to expose Brown Norway rats, with and without ovalbumin-induced allergic airway disease, to concentrated air particles (CAPs) generated from ambient air in an urban Detroit community where the pediatric asthma rate was three times higher than the national average. Rats were exposed to CAPs during the exposure periods in July (mean = 676 microg/m3) and September (313 microg/m3) of 2000. Twenty-four hours after exposures lung lobes were either lavaged with saline to determine cellularity and protein in bronchoalveolar lavage fluid (BALF), or removed for analysis by inductively coupled plasma-mass spectrometry (ICP-MS) to detect ambient PM2.5-derived trace element retention. PM2.5 trace elements of anthropogenic origin, lanthanum (La), vanadium (V), manganese (Mn), and sulfur (S), were recovered from the lung tissues of CAPs-exposed rats. Recovery of those pulmonary anthropogenic particles was further increased in rats with allergic airways. In addition, eosinophils and protein in BALF were increased only in allergic animals exposed to CAPs. These results demonstrate preferential retention in allergic airways of air particulates derived from identified local combustion sources after a short-term exposure. Our findings suggest that the enhancement of allergic airway responses by exposure to PM2.5 is mediated in part by increased pulmonary deposition and localization of potentially toxic elements in urban air.

Air Pollutants↗