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PubMed2005

Impact of the 2002 Canadian forest fires on particulate matter air quality in Baltimore city.

With increasing evidence of adverse health effects associated with particulate matter (PM), the exposure impact of natural sources, such as forest fires, has substantial public health relevance. In addition to the threat to nearby communities, pollutants released from forest fires can travel thousands of kilometers to heavily populated urban areas. There was a dramatic increase in forest fire activity in the province of Quebec, Canada, during July 2002. The transport of PM released from these forest fires was examined using a combination of a moderate-resolution imaging spectroradiometer satellite image, back-trajectories using a hybrid single-particle Lagrangian integrated trajectory, and local light detection and ranging measurements. Time- and size-resolved PM was evaluated at three ambient and four indoor measurement sites using a combination of direct reading instruments (laser, time-of-flight aerosol spectrometer, nephelometer, and an oscillating microbalance). The transport and monitoring results consistently identified a forest fire related PM episode in Baltimore that occurred the first weekend of July 2002 and resulted in as much as a 30-fold increase in ambientfine PM. On the basis of tapered element oscillating microbalance measurements, the 24 h PM25 concentration reached 86 microg/m3 on July 7, 2002, exceeding the 24 h national ambient air quality standard. The episode was primarily comprised of particles less than 2.5 microm in aerodynamic diameter, highlighting the preferential transport of the fraction of PM that is of greatest health concern. Penetration of the ambient episode indoors was efficient (median indoor-to-outdoor ratio 0.91) such that the high ambient levels were similarly experienced indoors. These results are significant in demonstrating the impact of a natural source thousands of kilometers away on ambient levels of and potential exposures to air pollution within an urban center. This research highlights the significance of transboundary air pollution and the need for studies that assess the public health impacts associated with such sources and transport processes.

Air Movements↗

PubMed2006

Distributions of PM2.5 source strengths for cooking from the Research Triangle Park particulate matter panel study.

Emission rates, decay rates, and cooking durations are reported from continuous PM2.5 (particulate matter less than 2.5 microm) concentrations measured using personal DataRam nephelometers (1-min time resolution) from the Research Triangle Park (RTP) PM panel study. The study (n = 37 participants) included monitoring for 7 consecutive days in each of four consecutive seasons (summer 2000 through spring 2001). Cooking episodes (n = 411) were selected using time-activity diaries and criteria for cooking event duration, peak concentration level, and decay curve quality. Averaged across all cooking events, mean source strengths were 36 mg/min (median = 12 mg/min), mean decay rates were 0.27 h(-1) (0.17 h(-1)), and mean cooking durations were 11 min (7 min). Cooking events were further separated into one of seven categories representing cooking method: burned food (oven cooking, toaster, or stovetop cooking), grilling, microwave, toaster oven, frying, oven cooking, and stovetop cooking. The highest mean source strengths were identified from burned food (mean = 470 mg/min), grilling (173 mg/min), and frying (60 mg/ min); differences between both burned food and grilling compared with all remaining cooking methods were statistically significant. Source strengths, decay rates, and cooking durations were also compared by season and typical meal times (8:00 a.m., 12:00 p.m., and 6:00 p.m.); differences were generally not statistically significant for these cases. Mean source strengths using electric appliances were typically a factor of 2 greater than those using gas appliances for identical cooking methods (frying, oven cooking, or stovetop cooking), although in all cases the difference was not statistically significant. Distributions of source strengths and decay rates for cooking events were also compared among study subjects to assess both within- and between-subject variability. Each subject's distribution of source strengths during the study tended to be either lower than the overall study average (and with lower variability) or higher than the overall study average (and with higher variability). No relationships could be found between source strength and either subject characteristics (age, gender, employment status) or home characteristic (daily air exchange rate). The large number of cooking events and the broad range of cooking activities included in this analysis makes the reported distributions of PM2.5 source strengths useful for probabilistic exposure modeling even though the study population was limited.

Air Pollutants↗

PubMedDate not supplied

A population exposure model for particulate matter: case study results for PM(2.5) in Philadelphia, PA.

A population exposure model for particulate matter (PM), called the Stochastic Human Exposure and Dose Simulation (SHEDS-PM) model, has been developed and applied in a case study of daily PM(2.5) exposures for the population living in Philadelphia, PA. SHEDS-PM is a probabilistic model that estimates the population distribution of total PM exposures by randomly sampling from various input distributions. A mass balance equation is used to calculate indoor PM concentrations for the residential microenvironment from ambient outdoor PM concentrations and physical factor data (e.g., air exchange, penetration, deposition), as well as emission strengths for indoor PM sources (e.g., smoking, cooking). PM concentrations in nonresidential microenvironments are calculated using equations developed from regression analysis of available indoor and outdoor measurement data for vehicles, offices, schools, stores, and restaurants/bars. Additional model inputs include demographic data for the population being modeled and human activity pattern data from EPA's Consolidated Human Activity Database (CHAD). Model outputs include distributions of daily total PM exposures in various microenvironments (indoors, in vehicles, outdoors), and the contribution from PM of ambient origin to daily total PM exposures in these microenvironments. SHEDS-PM has been applied to the population of Philadelphia using spatially and temporally interpolated ambient PM(2.5) measurements from 1992-1993 and 1990 US Census data for each census tract in Philadelphia. The resulting distributions showed substantial variability in daily total PM(2.5) exposures for the population of Philadelphia (median=20 microg/m(3); 90th percentile=59 microg/m(3)). Variability in human activities, and the presence of indoor-residential sources in particular, contributed to the observed variability in total PM(2.5) exposures. The uncertainty in the estimated population distribution for total PM(2.5) exposures was highest at the upper end of the distribution and revealed the importance of including estimates of input uncertainty in population exposure models. The distributions of daily microenvironmental PM(2.5) exposures (exposures due to time spent in various microenvironments) indicated that indoor-residential PM(2.5) exposures (median=13 microg/m(3)) had the greatest influence on total PM(2.5) exposures compared to the other microenvironments. The distribution of daily exposures to PM(2.5) of ambient origin was less variable across the population than the distribution of daily total PM(2.5) exposures (median=7 microg/m(3); 90th percentile=18 microg/m(3)) and similar to the distribution of ambient outdoor PM(2.5) concentrations. This result suggests that human activity patterns did not have as strong an influence on ambient PM(2.5) exposures as was observed for exposure to other PM(2.5) sources. For most of the simulated population, exposure to PM(2.5) of ambient origin contributed a significant percent of the daily total PM(2.5) exposures (median=37.5%), especially for the segment of the population without exposure to environmental tobacco smoke in the residence (median=46.4%). Development of the SHEDS-PM model using the Philadelphia PM(2.5) case study also provided useful insights into the limitations of currently available data for use in population exposure models. In addition, data needs for improving inputs to the SHEDS-PM model, reducing uncertainty and further refinement of the model structure, were identified.

Activities of Daily Living↗

PubMed2005

Particulate matter characterization at a coastal site in south-eastern Italy.

Several samples of airborne particulate matter (PM), collected from 6th November to 6th December 2003 at a coastal site in the south-east of Italy, have been analyzed by different techniques to characterize elemental composition and morphological properties of the inorganic PM fraction and obtain preliminary results on anthropogenic contributions. Al, Cr, Cu, Fe, Mn, V, Pb, Ti, Ca and Zn mass concentrations, evaluated by an inductively coupled plasma atomic emission spectrometer, account for up to l% of the bulk PM mass in the investigated samples. According to geochemical calculations, Ca, Al, Fe and Mn are predominantly of crustal origin, while Cr, Cu, Pb, V, Ti and Zn heavy metals are of anthropogenic origin. Ion chromatography analyses have identified sulfate (SO(4)(2-)) nitrate (NO(3)(-)), sodium (Na(+)), and ammonium (NH(4)(+)) as the main ionic components accounting for up to 38% of the total PM mass and up to 90% of the total ionic mass. Besides ion chromatography, X-ray energy dispersive (EDX) microanalyses have revealed the high variability of Cl: its weight concentration varies from about 24% to below the detection limit (>or=0.5%) in the investigated samples. The marked anti-correlation between the excess of S and the Cl/Na ratio has allowed inferring that reactions between sea salt particles and acidic sulfates, which liberate HCl gas to the atmosphere leaving particles enriched in non-sea-salt sulfates, have significantly contributed to chloride depletion. Morphological analyses by scanning electron microscopy have shown that about 90% of the total sampled particles have a diameter <or=5 microm.

Air Pollutants↗

PubMed2005

Dose dependency of adjuvant activity of particulate matter from five European sites in three seasons in an ovalbumin-mouse model.

Various particulate matter (PM) samples were tested for their adjuvant potency in an animal model of allergy (ovalbumin) in the European Union study entitled Respiratory Allergy and Inflammation Due to Ambient Particles. Coarse and fine ambient particles were collected during spring, summer, and winter in Rome, Oslo, Lodz, Amsterdam, and De Zilk. De Zilk, at the Dutch seaside, has mainly westerly winds and served as a negative pollution control. EHC-93 (Ottawa dust) was used as a positive control. We studied the adjuvant potency of the particle antibody responses to ovalbumin and histopathological changes in the lung. After a sensitization phase by coexposure to EHC-93 and ovalbumin, the antibody response to ovalbumin and inflammatory responses in the lung were huge. There was more adjuvant activity in reaction to 9-mg/ml samples than to 3-mg/ml samples. A best-fit analysis of these samples shows that the ambient coarse and fine particles at these sites, in combination with allergens, have severe to mild adjuvant activity in the order Lodz, Rome, Oslo, and Amsterdam. A high dose of the fine fraction was more potent than a high dose of the coarse fraction, except at De Zilk, where the reverse was true. Spring and winter PM was more potent than summer PM. Depending on the site, either a water-soluble or a water-insoluble fraction was responsible for the adjuvant activity. A concentration of 3 mg/ml is effective for screening high-activity samples, as is a concentration of 9 mg/ml for screening low-activity samples in the ovalbumin-mouse model.

Adjuvants, Immunologic↗

PubMed2004

Evaluation of DNA damage in mice topically exposed to total particulate matter from mainstream and sidestream smoke from cigarettes and bidis.

The genotoxic potential of total particulate matter (TPM) from mainstream smoke (MS) and sidestream smoke (SS) of Indian smoking products, namely cigarettes and bidis, as well as a brand of US cigarettes, was studied by determining the levels of bulky aromatic DNA adducts in mouse tissues. TPM from MS or SS of various smoking products [equal weights (2.5 mg) or the amount derived from equal (0.25) cigarette/bidi] was applied topically to mouse skin once a day for four consecutive days and adduct levels were determined in DNA from skin and lung by (32)P-post-labelling analysis. Relatively higher levels of bulky aromatic DNA adducts were noted in mouse skin treated with MS from a single Indian non-filter (INF) cigarette when compared with MS of a single bidi (with about half the product weight and one-quarter the tobacco compared with a cigarette), while comparable adduct levels were noted with SS from these two products. Considering the differences in the yields of constituents of tobacco smoke from the different products analyzed, the genotoxic potential of INF, Indian filter king (IFK) and American filter (AF) cigarettes as well as bidis was determined by topically applying an equal amount of TPM (rather than equal product-derived TPM). SS-derived TPM from all the products showed relatively higher levels of total polycyclic aromatic hydrocarbons and induced relatively higher levels of bulky aromatic DNA adducts than those derived from MS. The data indicate that TPM (MS + SS) from cigarettes appears to be more genotoxic than that from bidis and the contribution of tendu leaf (a non-tobacco bidi wrapper) to the generation of bulky aromatic DNA adducts appears to be significant, particularly in SS of bidis. Topical pretreatment with curcumin decreased the levels of TPM-derived adducts while pretreatment with dietary turmeric failed to show such protection.

Acetone↗

PubMed2001

Estimates of the health risk reductions associated with attainment of alternative particulate matter standards in two U.S. cities.

As part of its periodic re-evaluation of particulate matter (PM) standards, the U.S. Environmental Protection Agency estimated the health risk reductions associated with attainment of alternative PM standards in two locations in the United States with relatively complete air quality data: Philadelphia and Los Angeles. PM standards at the time of the analysis were defined for particles of aerodynamic diameter less than or equal to 10 microm, denoted as PM-10. The risk analyses estimated the risk reductions that would be associated with changing from attainment of the PM-10 standards then in place to attainment of alternative standards using an indicator measuring fine particles, defined as those particles of aerodynamic diameter less than or equal to 2.5 microm and denoted as PM-2.5. Annual average PM-2.5 standards of 12.5, 15, and 20 microg/m3 were considered in various combinations with daily PM-2.5 standards of 50 and 65 microg/m3. Attainment of a standard or set of standards was simulated by a proportional rollback of "as is" daily PM concentrations to daily PM concentrations that would just meet the standard(s). The predicted reductions in the incidence of health effects varied from zero, for those alternative standards already being met, to substantial reductions of over 88% of all PM-associated incidence (e.g., in mortality associated with long-term exposures in Los Angeles, under attainment of an annual standard of 12.5 microg/m3). Sensitivity analyses and integrated uncertainty analyses assessed the multiple-source uncertainty surrounding estimates of risk reduction.

Air Pollutants↗

PubMed2006

Fractionation of eleven elements by chemical bonding from airborne particulate matter collected in an industrial city in Argentina.

A four-step chemical sequential extraction procedure was used to evaluate the distribution of Al, As, Cr, Cu, Fe, Mn, Ni, Pb, Ti, V and Zn in airborne particulate matter collected on glass fibre filters using a high-volume sampler. Two sets of samples were collected in 2001 (winter and summer campaigns) in representative zones of an industrial city of Argentina. The leaching scheme was applied to PM-10 particles and consisted in extracting the elements in four fractions, namely soluble and exchangeable elements; carbonates, oxides and reducible elements; bound to organic matter and sulfidic metals; and residual elements. Metals and metalloids at microg g(-1) level were determined in each fraction by inductively coupled plasma optical emission spectrometry (ICP OES). Analyte concentration varied from 14 microg g(-1) (equivalent to 1.0 ng m(-3)) for As to 11.8 mg g(-1) (equivalent to 2,089 ng m(-3)) for Al. Seven elements, namely Al, Cr, Fe, Mn, Pb, Ti and Zn showed similar distributions in both seasons while As was distributed in a significantly different manner in each season. The results exhibited low As contents in the first and second fractions that could be associated with routine coal combustion and a high content in the third and fourth fractions of the summer samples that could be linked to the use of pesticides. Aluminium, As, Cu, Mn, Ni, Ti, V and Zn were found in different percentages in the more bioavailable aqueous fraction with As, Mn, V and Zn exhibiting solubilities greater than 1% while Cr and Pb being insoluble. The content of Al, Cr, Cu, Fe, Ni, Pb, and Zn in the residual fraction was, in average, higher than 50%. A comparative assessment of the use of the underlying information available from fractionation studies compared to that obtained from total element content was done for Fe and Mn. It showed that the results obtained using chemical sequential extraction procedures allowed further discrimination of the potential air pollution sources.

Air Pollutants↗

PubMed2006

The health relevance of ambient particulate matter characteristics: coherence of toxicological and epidemiological inferences.

The aim of this article is to review progress toward integration of toxicological and epidemiological research results concerning the role of specific physicochemical properties, and associated sources, in the adverse impact of ambient particulate matter (PM) on public health. Contemporary knowledge about atmospheric aerosols indicates their complex and variable nature. This knowledge has influenced toxicological assessments, pointing to several possible properties of concern, including particle size and specific inorganic and organic chemical constituents. However, results from controlled exposure laboratory studies are difficult to relate to actual community health results because of ambiguities in simulated PM mixtures, inconsistent concentration measurements, and the wide range of different biological endpoints. The use of concentrated ambient particulates (CAPs) coupled with factor analysis has provided an improved understanding of biological effects from more realistic laboratory-based exposure studies. Epidemiological studies have provided information concerning sources of potentially toxic particles or components, adding insight into the significance of exposure to secondary particles, such as sulfate, compared with primary emissions, such as elemental and organic carbon from transportation sources. Recent epidemiological approaches incorporate experimental designs that take advantage of broadened speciation monitoring, multiple monitoring stations, source proximity designs, and emission intervention. However, there continue to be major gaps in knowledge about the relative toxicity of particles from various sources, and the relationship between toxicity and particle physicochemical properties. Advancing knowledge could be facilitated with cooperative toxicological and epidemiological study designs, with the support of findings from atmospheric chemistry.

Carbon↗

PubMed2007

Impairment of mitochondrial function by particulate matter (PM) and their toxic components: implications for PM-induced cardiovascular and lung disease.

Increasing evidence suggests that reactive oxygen species (ROS) and oxidative stress are involved in PM-mediated lung and cardiovascular injury. The physical characteristics and the chemical composition of particulate matter (PM) play a key role in ROS generation in vitro and in vivo. The mitochondria are major subcellular targets for PM as well as a source of ROS production. ROS production is due to interference in mitochondrial electron transfer and PT pore opening by pro-oxidative PM components. Another possible mechanism is direct physical targeting by ambient ultrafine particles that lodge in and destroy mitochondrial structure. An understanding of the mitochondrial effects of PM is key in understanding the mechanisms of PM-induced adverse health effects.

Air Pollutants↗

PubMed1991

Inhibition of intercellular communication by airborne particulate matter.

To investigate the inhibition of gap junction mediated intercellular communication (IC) by extracts of airborne particulate matter (APM), V79 cells were incubated with extracts of APM and subsequently microinjected with the fluorescent dye Lucifer Yellow, after which the number of fluorescent (= communicating) cells was determined. To compare inhibitory effects on IC with mutagenicity, APM was also tested in the Salmonella microsome assay. Six different extracts were tested, two outdoor extracts representing a heavily polluted and a relatively clean sample, and four indoor extracts, taken either in livingrooms with or without wood combustion in an open fire place, or in a room with or without cigarette smoking. Non-cytotoxic doses of outdoor and indoor APM inhibited IC in V79 cells in a dose- and time-dependent manner. Mutagenicity data and IC data were correlated. These results suggest that APM has tumor promoter activity in addition to mutagenic activity.

Air Pollutants↗

PubMed2005

Redox activity of airborne particulate matter at different sites in the Los Angeles Basin.

Epidemiologic studies have shown associations between ambient particulate matter (PM) and adverse health outcomes including increased mortality, emergency room visits, and time lost from school and work. The mechanisms of PM-related health effects are still incompletely understood, but a hypothesis under investigation is that many of the adverse health effects may derive from oxidative stress, initiated by the formation of reactive oxygen species (ROS) within affected cells. While the adverse effects from PM have historically been associated with the airborne concentration of PM and more recently fine-particle PM, we considered it relevant to develop an assay to quantitatively measure the ability of PM to catalyze ROS generation as the initial step in the induction of oxidative stress. This ability of PM could then be related to different sources, chemical composition, and physical and spatial/temporal characteristics in the ambient environment. The measurement of ROS-forming ability in relation to sources and other factors will have potential relevance to control of redox-active PM. If oxidative stress represents a relevant mechanism of toxicity from PM, the measurement of redox activity represents a first step in the elucidation of the subsequent downstream processes. We have developed an assay for PM redox activity, utilizing the reduction of oxygen by dithiothreitol which serves as an electron source. We have found that PM will catalyze the reduction of oxygen and have examined the distribution and chemical characteristics of the redox activity of PM fractions collected in different sites in the Los Angeles Basin. Samples of concentrated coarse, fine, and ultrafine PM, obtained with aerosol concentrators, were studied with regard to their chemical properties and redox activity. Redox activity was highest in the ultrafine fraction, in agreement with results indicating ultrafines were the most potent toward inducing that heme oxygenase expression and depleting intracellular glutathione, which has relevance to induction of oxidative stress. Comparison of the redox activity with chemical composition showed a reasonable correlation of redox activity with elemental carbon (r(2)=0.79), organic carbon (r(2)=0.53), and with benzo[ghi]perylene (r(2)=0.82), consistent with species typically found in mobile emission sources.

Air Pollutants↗

PubMed2006

Biological material on inhaled coarse fraction particulate matter activates airway phagocytes in vivo in healthy volunteers.

BACKGROUND: In vitro, endotoxin on coarse fraction particulate matter (PM2.5-10) accounts for the majority of the ability of PM2.5-10 to induce cytokine responses from alveolar macrophages. OBJECTIVE: We examined in vivo whether inhaled PM2.5-10 from local ambient air induce inflammatory and immune responses in the airways of healthy human beings and whether biologic material on PM2.5-10 accounts for these effects. METHODS: On 3 separate visits, 9 healthy subjects inhaled nebulized saline (0.9%, control), PM2.5-10 collected from local ambient air that was heated to inactivate biological material (PM2.5-10-), or nonheated PM (PM2.5-10+). PM2.5-10 deposition (approximately 0.65 mg/subject) targeted the bronchial airways (confirmed by using radiolabeled aerosol), and induced sputum was obtained 2 to 3 hours postinhalation for analysis of cellular and biochemical markers of inflammation and innate immune function. RESULTS: Inhaled PM2.5-10+ induced elevated inflammation (% PMNs, macrophage mRNA TNF-alpha), increased eotaxin, upregulated immune surface phenotypes on macrophages (mCD14, CD11b, HLA-DR), and increased phagocytosis (monocytes) versus saline (P < .05). Biological inactivation of PM2.5-10 (PM2.5-10-) had no effect on neutrophilia but significantly (P < .05) attenuated mRNA TNF-alpha, eotaxin levels, cell surface marker responses, and phagocytosis. CONCLUSION: Biological components of PM2.5-10 are not necessary to induce neutrophil responses but are essential in mediating macrophage responses. The ability of PM2.5-10 to activate monocytic cells and potentially skew the airways toward an allergic phenotype by enhancing eotaxin levels may enhance responses to allergens or bacteria in individuals with allergy. CLINICAL IMPLICATIONS: PM2.5-10 might enhance the response of individuals with allergy to airborne bacteria.

Adolescent↗

PubMed2004

In vitro alveolar cytotoxicity of soluble components of airborne particulate matter: effects of serum on toxicity of transition metals.

Respiration of fossil fuel-derived airborne particulate matter (PM) has been linked to various pulmonary disorders. Transition metals contained in such PM, such as zinc, iron and vanadium, have been suggested as the primary culprits in PM-induced pulmonary distress by rat instillation studies. In this study, the cytotoxicity of zinc, iron, and vanadium on confluent monolayers of rat alveolar epithelial cells was evaluated as the inhibition of cellular succinate dehydrogenase metabolic activity as quantified via the MTT assay. In addition, the effect of culture medium serum concentration on the toxicities of these three metals was investigated. Of the three metals tested, zinc was the most toxic, with an EC50 of 0.6 mM in culture medium with 10% serum; vanadium and iron had EC50's of 3 and 4 mM, respectively. Serum in culture medium was found to substantially reduce the apparent toxicity of zinc: EC50's for zinc ranged from 0.6 mM in 10% serum to 0.1 mM in serum-free medium. Zinc toxicity analyses in various culture medium conditions demonstrated that the toxicity-reducing effect of serum was due largely and perhaps entirely, to serum albumin. Some, but not all of the effect of serum and albumin on zinc toxicity is apparently due to zinc-albumin binding.

Air Pollutants↗

PubMed2003

Recovery of semivolatile organic compounds during sample preparation: implications for characterization of airborne particulate matter.

Semivolatile compounds present special analytical challenges not met by conventional methods for analysis of ambient particulate matter (PM). Accurate quantification of PM-associated organic compounds requires validation of the laboratory procedures for recovery over a wide volatility and polarity range. To meet these challenges, solutions of n-alkanes (nC12-nC40) and polycyclic aromatic hydrocarbons PAHs (naphthalene to benzo[ghi]perylene) were reduced in volume from a solvent mixture (equal volumes of hexane, dichloromethane and methanol), to examine recovery after reduction in volume. When the extract solution volume reached 0.5 mL the solvent was entirely methanol, and the recovery averaged 60% for n-alkanes nC12-nC25 and PAHs from naphthalene to chrysene. Recovery of higher MW compounds decreased with MW, because of their insolubility in methanol. When the walls of the flasks were washed with 1 mL of equal parts hexane and dichloromethane (to reconstruct the original solvent composition), the recovery of nC18 and higher MW compounds increased dramatically, up to 100% for nC22-nC32 and then slowly decreasing with MW due to insolubility. To examine recovery during extraction of the components of the High Capacity Integrated Gas and Particle Sampler, the same standards were used to spike its denuders and filters. For XAD-4 coated denuders and filters, normalized recovery was >95% after two extractions. Recovery from spiked quartz filters matched the recovery from the coated surfaces for alkanes nC18 and larger and for fluoranthene and larger PAHs. Lower MW compounds evaporated from the quartz filter with the spiking solvent. This careful approach allowed quantification of organics by correcting for volatility- and solubility-related sample preparation losses. This method is illustrated for an ambient sample collected with this sampler during the Texas Air Quality Study 2000.

Air Pollutants↗

PubMed2004

Rapid evaluation of risk of white particulate matter in blood components by a statewide survey of transfusion reactions.

BACKGROUND: In January 2003, white particulate matter (WPM) was detected in blood components. Because the composition and cause of WPM was not understood at that time, there was uncertainty about whether WPM could endanger patient safety. To investigate possible adverse patient events associated with WPM, transfusion reaction rates were examined. STUDY DESIGN AND METHODS: A questionnaire was distributed to Georgia medical centers. Data collected included the number of components transfused and reported adverse reactions by component type from January 2002 through January 2003, and date, reaction type, and blood supplier for events in January 2003. RESULTS: Of 124 transfusion services contacted, 108 (87%) responded. During the survey period, there were 1213 reported transfusion reactions and 528,412 units transfused, or 2.3 reactions per 1000 units transfused; for RBCs, 2.4 (range, 1.8-3.1); plasma, 1.5 (range, 0.6-3.5); and PLTs, 3.4 (2.1-5.4) per 1000 units. Transfusion reaction rates by component for January 2003 did not differ significantly from the rate for January 2002 or for the calendar year. The 86 reported reactions that occurred in January 2003 were attributed to bacterial contamination (n = 2, 2.3%), other febrile nonhemolytic (n = 49, 57.0%), allergic (n = 14, 16.3%), and "other" reactions (n = 21, 24.4%); the proportions of reaction types did not differ significantly during the month. CONCLUSION: No overall changes in reported adverse reaction rates occurred over the survey period or in the proportion of reaction types during January 2003 when WPM was detected. Statewide surveillance of transfusion reactions could be useful to evaluate potential threats to blood safety.

Blood Specimen Collection↗

PubMed2006

Applying a moving total mortality count to the cities in the NMMAPS database to estimate the mortality effects of particulate matter air pollution.

OBJECTIVES: To apply a new method for estimating the association between daily ambient particulate matter air pollution (PM) and daily mortality to data from over 100 United States cities contained in the National Morbidity, Mortality, and Air Pollution Study (NMMAPS) database and to see whether the results from the 90 cities NMMAPS analysis are robust to this different modelling approach. This new method has recently been shown to provide improved estimates for the association between PM and daily mortality when every-day PM data are unavailable. It avoids the need for selecting a lag of PM at which the mortality effects of PM are to be investigated. METHODS: With the aid of analytical methods and databases developed for NMMAPS, Poisson log linear models controlling for long term trends and weather effects were used to estimate the association between PM and mortality for cities in the NMMAPS database using the new method. A two stage Bayesian hierarchical model was then used to combine city specific estimates to form a national average PM mortality effect estimate. RESULTS: A 10 microg/m3 increase in PM was associated with a 0.12% increment in total mortality and a 0.17% increment in cardiovascular and respiratory mortality. These results are consistent with those found in the NMMAPS analysis. CONCLUSIONS: There is a statistically significant association between short term changes in PM and mortality on average for the cities contained in the NMMAPS database. These findings are further evidence that this widespread pollutant adversely affects public health.

Adult↗

PubMed2004

Street-level concentrations of suspended particulate matter (SPM), nitrogen dioxide (NO2) and sulphur dioxide (SO2) in Pune City.

The concentration of suspended particulate matter (SPM), nitrogen dioxide (NO,) and sulphur dioxide (SO2) were measured at 13 important traffic intersections in Pune city. In order to study the contribution of these pollutants from motor vehicles, attention was focused on the roadside, street-level concentration. The statistical analysis of the sampling results indicates that there is not only high correlation between SPM and NO2 but the levels of these pollutants are above the National Ambient Air Quality Standards (NAAQS) laid down by the Central Pollution Control Board (CPCB), India. The SO, concentrations are found to be well below the NAAQS.

Air Pollutants↗