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PubMed2004

Particulate matter phenomenon: adverse event data and the effect of leukofiltration.

BACKGROUND: In February 2002, a multiorganizational task force investigated blood center reports of unusual particulate matter (PM) visible in packed red blood cells (RBC). A cohort study assessed increase in adverse events (AEs) related to this phenomenon, as well as the effect of post-leukofiltration (LF) on PM. METHODS: Two blood centers assessed AEs in patients transfused with RBCs having visible PM (classified as normal by-products of RBC preparation), PM RBCs subsequently LF, or RBCs without visible PM, and the effect of LF on PM removal. RESULTS: There was no difference in AEs in patients transfused with PM RBCs with or without LF compared to patients transfused with RBCs without visible PM. Subsequently filtered PM RBCs had acceptable residual WBC counts and median platelet removal of 92%. CONCLUSION: Transfusion of RBCs with visible PM or RBCs subsequently LF does not appear to increase the risk of an AE. LF use on PM RBCs results in the PM removal without adversely affecting filter performance. The lack of evidence of an increase in AE reports does not mean that there is no effect, and there may be a baseline AE rate attributable to PM which has not been thoroughly researched.

Blood Component Removal↗

PubMedDate not supplied

Determination of metals in thoracic fraction of ambient air particulate matter.

The present work deals with the optimization and validation of a method for the quantitative simultaneous ICP determination of metals in ambient air particulate matter. The attention has been focused on the thoracic fraction (PM10) and twelve different metals were chosen on the basis of their toxicity and of their possible use as chemical tracers. The microwave acidic digestion of the samples has been performed in the presence of different reagents and under different conditions and particular attention has been paid to the optimization of the whole analytical procedure and to the evaluation of accuracy and precision related to the single operative steps. The interferences due to the reagents and to the sampling supports have also been evaluated. In addition, the analytical procedure has been checked by examining the equivalence of results related to parallel sampled filters pairs.

Air Pollutants↗

PubMed2004

Particulate matter from tobacco versus diesel car exhaust: an educational perspective.

BACKGROUND: Air pollution is a common alibi used by adolescents taking up smoking and by smokers uncertain about quitting. However, environmental tobacco smoke (ETS) causes fine particulate matter (PM) indoor pollution exceeding outdoor limits, while new engines and fuels have reduced particulate emissions by cars. Data comparing PM emission from ETS and a recently released diesel car are presented. METHODS: A 60 m3 garage was chosen to assess PM emission from three smouldering cigarettes (lit sequentially for 30 minutes) and from a TDCi 2000cc, idling for 30 minutes. RESULTS: Particulate was measured with a portable analyser with readings every two minutes. Background PM10, PM2.5, and PM1 levels (mean (SD)) were 15 (1), 13 (0.7), and 7 (0.6) microg/m3 in the car experiment and 36 (2), 28 (1), and 14 (0.8) microg/m3 in the ETS experiment, respectively. Mean (SD) PM recorded in the first hour after starting the engine were 44 (9), 31 (5), and 13 (1) microg/m3, while mean PM in the first hour after lighting cigarettes were 343 (192), 319 (178), and 168 (92) microg/m3 for PM(10), PM2.5, and PM1, respectively (p < 0.001, background corrected). CONCLUSIONS: ETS is a major source of PM pollution, contributing to indoor PM concentrations up to 10-fold those emitted from an idling ecodiesel engine. Besides its educational usefulness, this knowledge should also be considered from an ecological perspective.

Air Pollutants↗

PubMed2004

On-road vehicle particulate matter and gaseous emission distributions in Las Vegas, Nevada, compared with other areas.

During the spring and summer of 2000, 2001, and 2002, gaseous and particulate matter (PM) fuel-based emission factors for approximately 150,000 low-tailpipe, individual vehicles in the Las Vegas, NV, area were measured via on-road remote sensing. For the gaseous pollutants (carbon monoxide, hydrocarbons, and nitrogen oxide), a commercial vehicle emissions remote sensing system (VERSS) was used. The PM emissions were determined using a Lidar-based VERSS. Emission distributions and their shapes were analyzed and compared with previous studies. The large skewness of the distributions is evident for both gaseous pollutants and PM and has important implications for emission reduction policies, because the majority of emissions are attributed to a small fraction of vehicles. Results of this Las Vegas study and studies at other geographical locations were compared. The gaseous pollutants were found to be close to those measured by VERSS in other U.S. cities. The PM emission factors for spark ignition and diesel vehicles are in the range of previous tunnel and dynamometer studies.

Air Pollutants↗

PubMedDate not supplied

Diesel particulate matter exposure to railroad train crews.

Exposure assessments were conducted aboard diesel locomotives. Results were evaluated to determine variables that affect exposure to DPM (diesel particulate matter) and to assess use of EC (elemental carbon) and OC (organic carbon) as surrogates for DPM. National Institute for Occupational Safety and Health Method 5040 was used for collection and analysis of samples in locomotives and in nonrailroad settings. The level of EC, but not OC, in locomotives was found to be significantly affected by position of exhaust stacks and windows. EC ranged from < 1 to 45 micrograms/m3 with a geometric mean (GM) of 3.7 micrograms/m3 and OC ranged from 4 to 4570 micrograms/m3 with a GM of 36.3 micrograms/m3. Background measurements of EC ranged from < 1 to 8 micrograms/m3 and OC levels were 4 to 84 micrograms/m3. This study confirms that train crew exposure to DPM is much lower than exposures for miners, is comparable to background urban exposures, and is lower than but comparable to exposures for truck drivers. It also indicates that EC levels are highly predictive of diesel exhaust exposure whereas OC levels are not, and that open windows and exhaust stack(s) in front of the locomotive cab have a significant effect on EC.

Air Pollutants, Occupational↗

PubMed2003

National maps of the effects of particulate matter on mortality: exploring geographical variation.

In this paper, we present national maps of relative rates of mortality associated with short-term exposure to particulate matter < 10 micro m in aerodynamic diameter (PM(10)). We report results for 88 of the largest metropolitan areas in the United States from 1987 to 1994 for all-cause mortality, combined cardiovascular and respiratory deaths, and other causes of mortality. Maximum likelihood estimates of the relative rate of mortality associated with PM(10)and the degree of statistical uncertainty were obtained for each of the 88 cities by fitting a separate log-linear regression of the daily mortality rate on air pollution level and potential confounders. We obtained Bayesian estimates of the relative rates by fitting a hierarchical model that takes into account spatial correlation among the true city-specific relative rates. We found that daily variations of PM(10) are positively associated with daily variations of mortality. In particular, the relative rate estimates of cardiovascular and respiratory mortality associated with PM(10) are larger on average than the relative rate estimates of all-cause and other-cause mortality. The estimated increase in the relative rate of death from cardiovascular and respiratory mortality, all-cause mortality, and other-cause mortality were 0.31% (95% posterior interval, 0.15-0.5), 0.22% (95% posterior interval, 0.1-0.38), and 0.13% (95% posterior interval, -0.05 to 0.29), respectively. Bayesian estimates of the city-specific relative rates ranged from 0.23% to 0.35% for cardiovascular and respiratory mortality, from 0.18% to 0.27% for all causes, and from 0.10% to 0.20% for other causes of mortality. The spatial characterization of effects across cities offers the potential to identify factors that could influence the effect of PM(10) on health, including particle characteristics, offering insights into mechanisms by which PM(10) causes adverse health effects.

Air Pollutants↗

PubMed1975

Peritoneal reactions to particulate matter in peritoneal dialysis solutions.

Peritoneal dialysis solutions were chemically injected into the peritoneal cavity of mice. A high percentage of the injected animals showed particulate matter in the peritoneal membranes associated with an inflammatory reaction. This was prevented by final filtration of the solutions through 0.22 and 0.45 mu filters. It is recommended that all chronic peritoneal dialysis be performed through a final filter.

Animals↗

PubMed2004

Characterization of fine organic particulate matter from Chinese cooking.

PM2.5 samples were collected by a three-stage cascade impactor at two kinds of Chinese restaurants to characterize fine organic particulate matter from Chinese cooking sources. Major individual organic compounds have been quantified by GC/MS, including series of alkanes, n-alkanoic acids, n-alkanals, alkan-2-ones and PAHs. Alkanes and ketones make up a significant fraction of particle-phase organic compounds, ranging from C11 to C26, and C9 to C19, respectively. In addition, other organic compound classes have been identified, such as alkanols, esters, furans, lactones, amides, and nitriles. The mass concentrations of fine particles, alkanes, n-alkanoic acids and PAHs in air emitted from the Uigur style cooking are hundreds times higher than ambient PM2.5 in Beijing.

Air Pollution, Indoor↗

PubMedDate not supplied

Real-time measurement of particulate matter deposition in the lung.

Air pollution and cigarette smoke are recognized health risks. A method was developed for the measurement of the deposition fraction (DF) of polydisperse particulate matter (PM) in human airways. Ten normal volunteers [three females, age range 18-67 years, mean age (SD) 43.9 (14)] made single breath exhalations after inhalation to total lung capacity. The exhaled breath was diverted to a multichannel laser diffraction chamber where the particulate profiler measured 0.3 - 1.0-microm particles. DF was inversely related to expiration flow-rate, 0.69 (0.02) at 4 l min-1 and 0.5 (0.01) at 13 l min-1, respectively (p<0.05), and was influenced by the inhalation flow-rate [0.70 (0.02) at 3 l min-1 and 0.59 (0.02) at 13 l min-1, respectively (p<0.05)], while no differences were found between nasal and oral inhalation (0.68 (0.05) versus 0.67 (0.06), p>0.05). Higher breath holding times were associated with elevated DF [0.74 (0.02) at 20 s, and 0.62 (0.05) without breath holding (p<0.01)]. When the expiratory flow was controlled and the breath hold time standardized, DF was reproducible (CV = 4.85%). PM can be measured in the exhaled breath and its DF can be quantified using a portable device. These methods may be useful in studies investigating the health effects of air pollution and tobacco smoke.

Adolescent↗

PubMed2003

Indoor environment quality in dental clinics: potential concerns from particulate matter.

PURPOSE: To provide a comprehensive assessment of the indoor environment of a representative dental office. METHODS: Health and comfort parameters, including carbon dioxide (CO2), respirable particulate matter (PM2.5), volatile organic compounds (VOCs), temperature, relative humidity, light and sound level, were measured at three sites over a 1-week period. Both real-time and integrated sampling methods were used, and clinic activities were recorded. Measurements were compared to guidelines and standards, and interactions between pollutant levels, emissions, and clinic activities were investigated using correlations, trend analyses, and a ventilation assessment. RESULTS: Comfort parameters were found to be within recommended values, with the exception of relative humidity, which was low but not unusual for the winter season investigated. Ventilation rates were within accepted guidelines. Integrated sampling showed that concentrations of VOCs were well below guidelines. However, PM2.5 levels exceeded ambient standards (by a factor of 2 to 6) throughout the building. Continuous trending allowed identification of peak levels, but correlations of clinic activities with measured concentrations were inconclusive. The results suggested that levels of air contaminants in dental clinics (with the exception of PM) are within guideline levels. With the recirculating ventilation systems found in most clinics and offices, particulate contaminants may rapidly disperse throughout a building. Improved capture, exhaust and filtration would decrease indoor PM concentrations. If contaminants are pathologic, the ramifications for practitioners may be considerable, and some specialists may be particularly at risk.

Acrylates↗

PubMed2000

The effect of physical form of orchardgrass hay on the passage of particulate matter through the rumen of sheep.

Four Texel wethers (60 to 64 kg) fitted with ruminal and duodenal cannulas were used to study the kinetics of particulate matter in the rumen and the series of processes involved in their selection and passage. They were fed, in eight equal meals, 1,200 g of a mixture of a chopped orchardgrass hay and ground (8-mm screen) and pelleted orchardgrass hay in 90/10, 50/50, 30/70, or 10/90 ratios, according to a 4 x 4 Latin square design. The particle size distributions in feed, chewed feed, and ruminal, reticular, and duodenal digesta were determined by a wet-sieving procedure. Indigestible lignin was used as an internal marker to trace the passage of particles through the rumen. Digesta flow measurement was performed using the double-marker technique. We used a three-pool model, which partitions particles through the large, medium, and small particle pools, to determine the passage of lignin through those pools. Particle pool sizes and rumen and pool mean retention times (MRT) of lignin and of the rumen MRT of an ideal marker introduced separately in each pool were corrected for the "filter bed" effect. Grinding and pelleting of hay decreased the MRT of the indigestible lignin pool in the rumen. Particle MRT decreased and then reached a plateau with increased proportion of ground/pelleted hay in the diet. The diet with a ratio of 50/50 of chopped and ground/pelleted hay was the most favorable for the exit of particles from the rumen because of both a higher outflow rate from the rumen of particles eligible to exit and a sufficient comminution rate of larger particles to supply particles that were able to pass. For all diets, the large-particle comminution rate was always higher than the small-particle outflow rate, indicating that comminution was not the limiting step for passage. These results were the consequence of the curvilinear and opposite evolutions of both the particulate lignin pool in, and outflow from, the rumen. Those results contribute to an improved explanation of the mechanisms involved in the outflow of particles from the rumen.

Animal Feed↗

PubMedDate not supplied

Characterization of organic extracts from standard reference materials 1649, 'urban dust/organics,' and 1650, 'diesel particulate matter', using a microsuspension assay. A WHO/IPCS/CSCM study.

Mutagenicity associated with replicate organic extracts from standard reference materials 1649 'urban dust/organics' (air particles), and 1650, 'diesel particulate matter' (diesel particles), was determined using a Salmonella microsuspension assay. The results indicate that the mutagenicity of samples such as these can readily be determined using the microsuspension assay with only 5% of the mass required for the standard plate incorporation assay. In general, 80% of the variation in mutagenic activity was due to the bioassay procedure and 20% to the extraction process. Extracts from both samples had primarily direct-acting mutagenicity as there were no significant differences in responses with and without metabolic activation (S9). The TA98-S9 mean air particles mutagenic activities (C.V., %) based on mass of extractable organics or particles were 4.4 (4.7%) and 0.29 (3.6%) revertants/micrograms, respectively, and for the diesel particles were 66 (44%) and 12 (29%) revertants/microgram, respectively. More of the observed direct-acting mutagenicity in the diesel particles extracts was due to nitro-substituted compounds because there were significant reductions in activity with TA98NR (45% of TA98 -S9) and TA98-1,8-DNP6 (21% of TA98 -S9). In the air particles extracts, the TA98NR activities were not significantly different from TA98 -S9 but the TA98-1,8-DNP6 levels were.

Air Pollutants↗

PubMed2002

Field testing of particulate matter continuous emission monitors at the DOE Oak Ridge TSCA incinerator. Toxic Substances Control Act.

A field study to evaluate the performance of three commercially available particulate matter (PM) continuous emission monitors (CEMs) was conducted in 1999-2000 at the US Department of Energy (DOE) Toxic Substances Control Act (TSCA) Incinerator. This study offers unique features that are believed to enhance the collective US experience with PM CEMs. The TSCA Incinerator is permitted to treat PCB-contaminated RCRA hazardous low-level radioactive wastes. The air pollution control system utilizes MACT control technology and is comprised of a rapid quench, venturi scrubber, packed bed scrubber, and two ionizing wet scrubbers in series, which create a saturated flue gas that must be conditioned by the CEMs prior to measurement. The incinerator routinely treats a wide variety of wastes including high and low BTU organic liquids, aqueous, and solid wastes. The various possible combinations for treating liquid and solid wastes may present a challenge in establishing a single, acceptable correlation relationship for individual CEMs. The effect of low-level radioactive material present in the waste is a unique site-specific factor not evaluated in previous tests. The three systems chosen for evaluation were two beta gauge devices and a light scattering device. The performance of the CEMs was evaluated using the requirements in draft Environmental Protection Agency (EPA) Performance Specification 11 (PS11) and Procedure 2. The results of Reference Method 5i stack tests for establishing statistical correlations between the reference method data and the CEMs responses are discussed.

Environmental Monitoring↗

PubMed2004

Development and application of a mobile laboratory for measuring emissions from diesel engines. 2. Sampling for toxics and particulate matter.

Limited data are available on the emission rates of speciated volatile and semivolatile organic compounds, as well as the physical and chemical characteristics of fine particulate matter (PM) from mobile, in-use diesel engines operated on the road. A design for the sampling of these fractions and the first data from in-use diesel sources are presented in this paper. Emission rates for carbonyls, 1,3-butadiene, benzene, toluene, xylene, PM, and elemental and organic carbon (EC and OC) are reported for a vehicle driven while following the California Air Resources Board (ARB) four-mode heavy heavy-duty diesel truck (HHDDT) cycle and while transiting through a major transportation corridor. Results show that distance specific emission rates are substantially greater in congested traffic as compared with highway cruise conditions. Specifically, emissions of toxic compounds are 3-15 times greater, and PM is 7 times greater under these conditions. The dependence of these species on driving mode suggests that health and source apportionment studies will need to account for driving patterns in addition to emission factors. Comparison of the PM/NOx ratios obtained for the above tests provides insight into the presence and importance of "off-cycle" emissions during on-road driving. Measurements from a stationary source (operated and tested at constant engine speed) equipped with an engine similar to that in the HHDDT yielded a greater understanding of the relative dependence of emissions on load versus engine transients. These data are indicative of the type of investigations made possible by the development of this novel laboratory.

Air Pollutants↗

PubMed2004

Elevated personal exposure to particulate matter from human activities in a residence.

Continuous laser particle counters collocated with time-integrated filter samplers were used to measure personal, indoor, and outdoor particulate matter (PM) concentrations for a variety of prescribed human activities during a 5-day experimental period in a home in Redwood City, CA, USA. The mean daytime personal exposures to PM(2.5) and PM(5) during prescribed activities were 6 and 17 times, respectively, as high as the pre-activity indoor background concentration. Activities that resulted in the highest exposures of PM(2.5), PM(5), and PM(10) were those that disturbed dust reservoirs on furniture and textiles, such as dry dusting, folding clothes and blankets, and making a bed. The vigor of activity and type of flooring were also important factors for dust resuspension. Personal exposures to PM(2.5) and PM(5) were 1.4 and 1.6 times, respectively, as high as the indoor concentration as measured by a stationary monitor. The ratio of personal exposure to the indoor concentration was a function of both particle size and the distance of the human activity from the stationary indoor monitor. The results demonstrate that a wide variety of indoor human resuspension activities increase human exposure to PM and contribute to the "personal cloud" effect.

Activities of Daily Living↗

PubMed2003

Effects of inhaled ambient particulate matter on pulmonary antimicrobial immune defense.

Respiratory-tract infection, specifically pneumonia, contributes substantially to the increased morbidity and mortality among elderly individuals exposed to airborne particulate matter of <10 microm diameter (PM(10)). These epidemiological findings suggest that PM(10) may act as an immunosuppressive factor that can undermine normal pulmonary antimicrobial defense mechanisms. To investigate whether, and how, compromised pulmonary immunocompetence might contribute to increased mortality, two sets of laboratory studies were performed. The first examined the effects of a single inhalation exposure to concentrated ambient PM(2.5) (CAPS) from New York City air on pulmonary/systemic immunity and on the susceptibility of exposed aged rats to subsequent infection with Streptococcus pneumoniae. The second set of studies determined whether CAPS exposure, at a concentration approximating or somewhat greater than the promulgated 24-h NAAQS of 65 microg/m(3), could exacerbate an ongoing infection. Taken together, results demonstrated that a single exposure of healthy animals to CAPS had little effect on pulmonary immune function or bacterial clearance during subsequent challenge with S. pneumoniae. Alternatively, CAPS exposure of previously infected rats significantly increased bacterial burdens and decreased percentages of lavageable neutrophils and proinflammatory cytokine levels compared to those in infected filtered-air-exposed controls. These studies demonstrate that a single exposure to ambient PM(2.5) compromises a host's ability to handle ongoing pneumococcal infections and support the epidemiological findings of increased pneumonia-related deaths in ambient PM-exposed elderly individuals.

Aging↗

PubMed2003

Particulate matter in California: part 2--Spatial, temporal, and compositional patterns of PM2.5, PM10-2.5, and PM10.

Geographic and temporal variations in the concentration and composition of particulate matter (PM) provide important insights into particle sources, atmospheric processes that influence particle formation, and PM management strategies. In the nonurban areas of California, annual-average PM2.5 and PM10 concentrations range from 3 to 10 microg/m3 and from 5 to 18 microg/m3, respectively. In the urban areas of California, annual-averages for PM2.5 range from 7 to 30 microg/m3, with observed 24-hr peaks reaching levels as high as 160 microg/m3. Within each air basin, exceedances are a mixture of isolated events as well as periods of elevated PM2.5 concentrations that are more prolonged and regional in nature. PM2.5 concentrations are generally highest during the winter months. The exception is the South Coast Air Basin, where fairly high values occur throughout the year. Annual-average PM2.5 mass, as well as the concentrations of major components, declined from 1988 to 2000. The declines are especially pronounced for the sulfate (SO4(2-)) and nitrate (NO3-) components of PM2.5 and PM10) and correlate with reductions in ambient levels of oxides of sulfur (SOx) and oxides of nitrogen (NOx). Annual averages for PM10-2.5 and PM10 exhibited similar downwind trends from 1994 to 1999, with a slightly less pronounced decrease in the coarse fraction.

Aerosols↗

PubMed2003

Particulate matter in California: part 1--Intercomparison of several PM2.5, PM10-2.5, and PM10 monitoring networks.

It will be many years before the recently deployed network of fine particulate matter with an aerodynamic diameter less than 2.5 microm (PM2.5) Federal Reference Method (FRM) samplers produces information on nonattainment areas, trends, and source impacts. However, data on PM2.5 and its major constituents have been routinely collected in California for the past 20 years. The California Air Resources Board operated as many as 20 dichotomous (dichot) samplers for PM2.5 and coarse PM (PM10-2.5). The California Acid Deposition Monitoring Program (CADMP) collected 12-h-average PM2.5 and PM10 from 1988 to 1995 at ten urban and rural sites and 24-h-average PM2.5 at five urban sites since 1995. Beginning in 1994, the Children's Health Study collected 2-week averages of PM2.5 in 12 communities in southern California using the Two-Week Sampler (TWS). Comparisons of collocated samples establish relationships between the dichot, CADMP, and TWS samplers and the 82-site network of PM2.5 FRM samplers deployed since 1999 in California. PM mass data from the different monitoring programs have modest to high correlation to FRM mass data, fairly small systematic biases and negative proportional biases ranging from 7 to 22%. If the biases are taken into account, all of the programs should be considered comparable with the FRM program. Thus, historical data can be used to develop long-term PM trends in California.

Air Pollutants↗