SEARCH · PubMed Health

Results for “Particulate Matter”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 73 records · Page 4Linked to original sources

PubMed2006

Identification and chemical characterization of industrial particulate matter sources in southwest Spain.

A detailed physical and chemical characterization of coarse particulate matter (PM10) and fine particulate matter (PM2.5) in the city of Huelva (in Southwestern Spain) was carried out during 2001 and 2002. To identify the major emission sources with a significant influence on PM10 and PM2.5, a methodology was developed based on the combination of: (1) real-time measurements of levels of PM10, PM2.5, and very fine particulate matter (PM1); (2) chemical characterization and source apportionment analysis of PM10 and PM2.5; and (3) intensive measurements in field campaigns to characterize the emission plumes of several point sources. Annual means of 37, 19, and 16 microg/m3 were obtained for the study period for PM10, PM2.5, and PM1, respectively. High PM episodes, characterized by a very fine grain size distribution, are frequently detected in Huelva mainly in the winter as the result of the impact of the industrial emission plumes on the city. Chemical analysis showed that PM at Huelva is characterized by high PO4(3-) and As levels, as expected from the industrial activities. Source apportionment analyses identified a crustal source (36% of PM10 and 31% of PM2.5); a traffic-related source (33% of PM10 and 29% of PM2.5), and a marine aerosol contribution (only in PM10, 4%). In addition, two industrial emission sources were identified in PM10 and PM2.5: (1) a petrochemical source, 13% in PM10 and 8% in PM2.5; and (2) a mixed metallurgical-phosphate source, which accounts for 11-12% of PM10 and PM2.5. In PM2.5 a secondary source has been also identified, which contributed to 17% of the mass. A complete characterization of industrial emission plumes during their impact on the ground allowed for the identification of tracer species for specific point sources, such as petrochemical, metallurgic, and fertilizer and phosphate production industries.

Air Pollutants↗

PubMed1981

Effects of particulate matter from carbenicillin disodium solution on human macrophages in vitro.

The effects of particulate matter from reconstituted carbenicillin disodium on cultures of human macrophages was studied. Particulate matter from commercially available carbenicillin disodium was collected on 0.1 micrometer membrane filters. Monocytes/macrophages obtained from human peripheral blood were cultivated on the particle bearing surface of the filter in culture medium. The cells were incubated in tissue cultures dishes at a concentration of 2 x 10(6) cells per dish. Experimental and control cultures were observed over six days for changes in morphology, cell membrane integrity, phagocytic capacity, and viability. Exposure of the cells to the particles was not cytotoxic. Cell membrane integrity remained intact as shown by no increase of LDH in the extracellular fluid. The phagocytic capacity of the cell system was not impaired as assessed by observing the intracellular levels of glucose-6-phosphate dehydrogenase. Morphological changes as monitored by phase contrast and bright field microscopy were consistent with increased cellular activity. Particulate matter from carbenicillin disodium may not be toxic to human macrophages in vitro for up to six days. At the concentrations used in this study, particulate matter did not lower the phagocytic capacity of human macrophages in vitro.

Carbenicillin↗

PubMed2006

Seasonal variations and mass closure analysis of particulate matter in Hong Kong.

The chemical characteristics of ambient particulate matters in urban and rural areas of Hong Kong were determined in this study. A monitoring program starting from November 2000 to February 2001 (winter) and June 2001 to August 2001 (summer) for PM10 and PM2.5 was performed at three monitoring stations in Hong Kong. Twenty-four-hour PM10 and PM2.5 samples were collected once every 6 days at two urban sites, PolyU and KT, and every 12 days at a background site, HT, with Hi-Vol samplers. High concentrations of OC, EC (except in PolyU), water-soluble ions and elements were observed in winter among the three sampling sites for PM10 and PM2.5 fractions. Seasonal variations were significant in background HT. Dilution effect due to the increase in mixing depth and precipitation in summer reduced the concentrations of particulate matters. Long-range transport could contribute to the higher concentrations of particulate matter in the winter. Chemical mass closure calculations were performed for PM10 and PM2.5 observed. Mass closure improved when separate factors (1.4 and 1.9 respectively) were used to convert water-soluble organic carbon (WSOC) and water-insoluble organic carbon (WINSOC) into corresponding organic masses. The urban sites showed high percentages of water-soluble ions in winter and high percentages of carbonaceous species in summer. Better results were obtained for the chemical mass closure analysis in winter than in summer. High temperature and solar radiation in summer increased the rate of the complex photochemical reaction in the atmosphere. Therefore the chemical mass closure analysis would underestimate the volatized species and secondary aerosols during summer.

Air Pollutants↗

PubMedDate not supplied

Multipollutant exposures and health responses to particulate matter.

Epidemiological methods provide opportunities to study interactions of pollutants in complex environments. During the study of health and the environment and the evaluation of particulate matter in Tucson, we found that type, location, and temporality of particulate matter exposures were critical with respect to the various interactions that related to health effects. Indoor particulate matter interacted with other components of particulate matter found in tobacco smoke, as evidenced by lung function. The interaction of environmental tobacco smoke with indoor formaldehyde caused various symptoms. Other interactions occurred between indoor and outdoor forms of particulate matter, which caused symptoms in some of the subjects.

Air Pollutants↗

PubMed2002

What's wrong with the National Ambient Air Quality Standard (NAAQS) for fine particulate matter (PM(2.5))?

Associations between airborne concentrations of fine particulate matter (PM(2.5)) and mortality rates have been investigated primarily by ecologic or semiecologic epidemiology studies. Many investigators and regulatory agencies have inferred that the weak, positive association often observed is causal, that it applies to all forms of airborne PM(2.5), and that current ambient levels of PM(2.5) require reduction. Before implementing stringent regulations of ambient PM(2.5), analysts should pause to consider whether the accumulated evidence is sufficient, and sufficiently detailed, to support the PM(2.5) National Ambient Air Quality Standard. We take two tacks. First, we analyze the toxicologic evidence, finding it inconsistent with the notion that current ambient concentrations of all forms of fine particulate matter should affect pulmonary, cardiac, or all-cause mortality rates. More generally, we note that the thousands of forms of PM(2.5) are remarkably diverse, yet the PM(2.5) NAAQS presumes them to be identical toxicologically, and presumes that reducing ambient concentrations of any form of PM(2.5) will improve public health. Second, we examine the epidemiologic evidence in light of two related examples of semiecologic associations, examples that both inform the PM-mortality association and have been called into question by individual-level data. Taken together, the toxicologic evidence and lessons learned from analogous epidemiologic associations should encourage further investigation of the association between particulate matter and mortality rates before additional regulation is implemented, and certainly before the association is characterized as causal and applicable to all PM(2.5).

Air Pollutants↗

PubMed2002

Impact of long-term exposure to air particulate matter on life expectancy and survival rate of Shanghai residents.

OBJECTIVE: To evaluate the impact of long-term air particulate matter exposure on the life expectancy and survival rate of Shanghai residents. METHODS: Epidemiology--based exposure-response function was used for the calculation of attributable deaths to air particulate matter in Shanghai, and the effect of long-term exposure to particulate matter on life expectancy and survival rate was estimated using the life table of Shanghai residents in 1999. RESULTS: It was shown that in 1999, the long-term air particulate matter exposure caused 1.34-1.69 years reduction of life expectancy and a decrease of survival rate for each age group of Shanghai residents. CONCLUSION: The effect of long-term exposure to air particulate matter on life expectancy is substantial in Shanghai.

Adolescent↗

PubMed1993

Pulmonary function changes in children associated with fine particulate matter.

During winter months many neighborhoods in the Seattle metropolitan area are heavily affected by particulate matter from residential wood burning. A study was conducted to investigate the relationship between fine particulate matter and pulmonary function in young children. The subjects were 326 elementary school children, including 24 asthmatics, who lived in an area with high particulate concentrations predominantly from residential wood burning. FEV1 and FVC were measured before, during and after the 1988-1989 and 1989-1990 winter heating seasons. Fine particulate matter was assessed using a light-scattering instrument. Analysis of the relationship between light scattering and lung function indicated that an increase in particulate air pollution was associated with a decline in asthmatic children's pulmonary function. FEV1 and FVC in the asthmatic children dropped an average of 34 and 37 ml respectively for each 10(-4) m-1 increase in sigma sp. This sigma sp increase corresponds to an increase in PM2.5 of 20 micrograms/m3. It is concluded that fine particulate matter from wood burning is significantly associated with acute respiratory irritation in young asthmatic children.

Air Pollutants↗

PubMed2001

A case-crossover analysis of particulate matter air pollution and out-of-hospital primary cardiac arrest.

Numerous epidemiologic studies have reported increases in the daily incidence of cardiovascular mortality and morbidity associated with increases in daily levels of particulate matter air pollution. We studied the association between the incidence of primary cardiac arrest and two daily measures of particulate matter using a case-crossover study of 362 cases of out-of-hospital cardiac arrest. All cases were attended by paramedics and had no history of clinically recognized heart disease or life-threatening comorbidities. We compared particulate matter levels at index times with particulate matter levels from referent days matched on day of week within strata defined by month and year. The estimated relative risk at a lag of 1 day for an interquartile range (IQR) change in nephelometry (0.51 x 10(-1) km(-1)) was 0.893 (95% CI = 0.779-1.024). The estimated relative risk at a lag of 1 day for an IQR change in PM10 (19.3 microg m(-3)) was 0.868 (95% CI = 0.744-1.012). Other lag periods gave similar results. We did not find evidence of confounding by carbon monoxide or sulfur dioxide. Analysis of effect modification by individual-level variables did not reveal any susceptible subgroups. These findings do no support an association between particulate matter and increased risk of primary cardiac arrest among persons without clinically recognized heart disease. The null results of this study may result from several factors, including the highly selected nature of this case series and the relatively low particulate matter levels in the Seattle metropolitan area.

Adult↗

PubMed2001

Environmental occurrence of nitrotriphenylene observed in airborne particulate matter.

1- and 2-Nitrotriphenylenes were found in the airborne particulate matter extracts collected in central Tokyo between the winter of 1998 and the winter of 1999. In particular, we have identified and quantified nitrotriphenylenes in the airborne particulate matter extracts collected over four consecutive 6-h periods on 2 December 1999. The concentrations of 1- and 2-nitrotriphenylene ranged from 0.04 to 0.44 and from 0.02 to 0.47 ng/m3, respectively, and the concentrations in the airborne particulate matter extracts collected during the 18:00-24:00 h time period were the highest of the four collection periods. 1-Nitropyrene and 2-nitrofluoranthene were also identified and quantified in the four 6-h samples. Although the concentrations of 1- and 2-nitrotriphenylenes were not higher than that of 2-nitrofluoranthene except during the 18:00-24:00 h time period, the concentrations were much higher than that of 1-nitropyrene during the four collection periods. The higher concentrations of 1- and 2-nitrotriphenylenes during the 18:00-24:00 h time period are presumably responsible for the high reactivity of parent triphenylene with NO2/NO3/N2O5, and high stability of 1- and 2-nitrotriphenylenes toward O3 + O2. In addition, the observed isomer distribution of nitrotriphenylenes suggested that direct emission of nitrotriphenylenes is also a source as well as their atmospheric formation.

Air Pollutants↗

PubMed2005

Ultrasound-assisted extraction and on-line LC-GC-MS for determination of polycyclic aromatic hydrocarbons (PAH) in urban dust and diesel particulate matter.

A method has been developed for determination of polycyclic aromatic hydrocarbons (PAH) in particulate matter from ambient air and diesel exhaust emissions. It is reproducible and accurate and, compared with similar methods for analysis of individual PAH components in complex matrices, it is relatively fast and simple. Single PAH components can be determined in samples of particulate matter from ambient air and diesel exhaust emissions with LOD of approximately 1 pg/sample. Further, sample throughput is high, because more than 20 samples can be extracted and prepared for analysis in one working (8-h) day. The particulate matter is subjected to ultrasound-assisted extraction, a technique that is shown to extract PAH from particulate material with efficiencies fully comparable with those of Soxhlet extraction. An aliphatic/PAH-enriched fraction is obtained by solid-phase extraction before isolation, separation, and identification/quantification of PAH by on-line liquid chromatography-gas chromatography-mass spectrometry. The method was validated by analysis of US National Institute of Standards and Technology (NIST) Standard Reference Materials (SRM) 1649a, Urban Dust, and 2975, Diesel Particulate Matter. Results from the method are in good agreement with the NIST-certified PAH concentrations and with NIST reference PAH concentrations.

Air Pollutants↗

PubMed2003

An automatic method for the determination of carcinogenic 1-nitropyrene in extracts from automobile exhaust particulate matter.

An automatic method for the determination of carcinogenic 1-nitropyrene in extracts from automobile exhaust particulate matter has been developed. Organic matter was extracted from particulate matter and the extract was concentrated. Then the extract was injected into a two-dimensional (2D) high-performance liquid chromatograph (HPLC) with a fluorescence detection system. To improve the sensitivity a large sample volume (300 microl) was applied to the HPLC system using the double on-column focusing technique. To achieve full automation and high selectivity a reduction column packed with platinum black was introduced after the 2D HPLC system using a C18 column as the primary column and a pentabromobenzyl column as the secondary column. This HPLC system could determine 0.01-3,000 ng ml(-1) of 1-nitropyrene in an extract from diesel and gasoline exhaust particulate matter at 40 min intervals.

Carcinogens↗

PubMedDate not supplied

Description of the carbonaceous particulate matter evolution in an urban area.

The ground concentrations of particulate matter, total carbon, elemental carbon and organic carbon were measured in a monitoring station located inner a park in downtown Rome. The description of the evolution of the boundary layer is given by radon concentration measurements. The results show that the particulate matter of Rome contains about 30% of carbonaceous matter. The elemental and organic carbon behaviours show that elemental carbon is essentially a primary pollutant emitted directly from vehicular traffic and organic carbon behaviour instead can be primary (combustion and biogenic emission) and secondary. A chemical fine particulate matter mass balance is given; an organic carbon investigation has been carried out in order to determine n-alkanes, n-alkanoic acids and polycyclic aromatic hydrocarbons.

Air Pollutants↗

PubMed2006

Genotoxicity induced by fine urban air particulate matter in the macrophages cell line RAW 264.7.

Recent studies support a participation of fine airborne particulate matter (PM) with an aerodynamic diameter less than 2.5 microm in the effects of air pollutants on health. Particulate matter was collected in an urban area of L'Aquila during the winter 2004. Fine particulate samples were analyzed by X-ray photoelectron spectroscopy (XPS) to determine the chemical inventory of the aerosol particle surfaces and to evaluate the weight of characteristic functional groups of the most frequent carbon-containing organic pollutant compounds (C-C/C-H, C-O/C-N, C=O, COOH). The most important contributor to the mass of fine particulate matter was carbon. The overall purpose of this work was to determine the in vitro toxicity and genotoxicity of fine PM in cultured macrophages (RAW 264.7 cells) since the biological target of inhaled PM are the pulmonary epithelium and resident macrophages. In parallel in vitro toxicity assays were used including cell viability and apoptosis. Genotoxicity was evaluated by the micronucleus (MN) assay. The viability of macrophages was assessed by the MTT method; apoptosis by an ELISA test for programmed cell death (PCD) was determined after RAW 264.7 cells treatment. Concentration of 1, 3 and 10 microg/cm2 of fine particles induced micronuclei in a dose-dependent manner. We also compared the effects of fine PM with those of fine carbon black particles (CB) in similar doses. Fine carbon black particles were consistently less genotoxic than the fine atmospheric particles, suggesting that the contaminants adsorbed on them (i.e. carbon-containing organic compounds in addition to metal oxides and metal salts) are involved in genotoxicity. Fine PM reduced cellular proliferation. Overall, the results presented here demonstrate the utility of in vitro tests in mouse cells for testing genotoxicity of urban air particulate matter.

Air Pollutants↗

PubMed2002

The influence of ambient coarse particulate matter on asthma hospitalization in children: case-crossover and time-series analyses.

In this study, we used both case-crossover and time-series analyses to assess the associations between size-fractionated particulate matter and asthma hospitalization among children 6-12 years old living in Toronto between 1981 and 1993. Specifically, we used exposures averaged over periods varying from 1 to 7 days to assess the effects of particulate matter on asthma hospitalization. We calculated estimates of the relative risk of asthma hospitalization adjusted for daily weather conditions (maximum and minimum temperatures, and average relative humidity) for an incremental exposure corresponding to the interquartile range in particulate matter. Both bidirectional case-crossover and time-series analyses revealed that coarse particulate matter (PM10-2.5) averaged over 5-6 days was significantly associated with asthma hospitalization in both males and females. The magnitude of this effect appeared to increase with increasing number of days of exposure averaging for most models, with the relative risk estimates stabilizing at about 6 days. Using a bidirectional case-crossover analysis, the estimated relative risks were 1.14 [95% confidence interval (CI), 1.02, 1.28] for males and 1.18 (95% CI, 1.02, 1.36) for females, for an increment of 8.4 microg/m(3) in 6-day averages of PM10-2.5. The corresponding relative risk estimates were 1.10 and 1.18, respectively, when we used time-series analysis. The effect of PM10-2.5 remained positive after adjustment for the effects of the gaseous pollutants carbon monoxide (CO), nitrogen dioxide (NO2), sulfur dioxide (SO2), and ozone (O3). We did not find significant effects of fine particulate matter (PM2.5) or of thoracic particulate matter (PM10) on asthma hospitalizations using either of these two analytic approaches. For the most part, relative risk estimates from the unidirectional case-crossover analysis were more pronounced compared with both bidirectional case-crossover and time-series analyses.

Air Pollutants↗

PubMed2005

Differential regulation of the lung endothelin system by urban particulate matter and ozone.

Periodic elevation of ambient particulate matter and ozone levels is linked to acute cardiac morbidity and mortality. Increased plasma levels of the potent vasoconstrictor endothelin (ET)-1, a prognostic indicator of cardiac mortality, have been detected in both animal models and humans after exposure to air pollutants. The lungs are the primary source of circulating ET-1, but the direct effects of individual air pollutants and their interaction in modulating the pulmonary endothelin system are unknown. Fischer-344 rats were exposed to particles (0, 5, 50 mg/m3 EHC-93), ozone (0, 0.4, 0.8 ppm), or combinations of particles and ozone for 4 h. Changes in gene expression were measured using real-time reverse transcription polymerase chain reaction immediately after exposure and following 24 h recovery in clean air. Both pollutants individually increased preproET-1, endothelin converting enzyme-1, and endothelial nitric oxide synthase mRNA levels in the lungs shortly after exposure, consistent with the concomitant increase in plasma of the 21 amino acid ET-1[1-21] peptide measured by HPLC-fluorescence. PreproET-1 mRNA remained elevated 24 h after exposure to particles but not after ozone, in line with previously documented changes of the peptide in plasma. Both pollutants transiently increased endothelin-B receptor mRNA expression, while ozone decreased endothelin-A receptor mRNA levels. Coexposure to particles plus ozone increased lung preproET-1 mRNA but not plasma ET-1[1-21], suggesting alternative processing or degradation of endothelins. This coincided with an increase in the lungs of matrix metalloproteinase-2 (MMP-2), an enzyme that cleaves bigET-1 to ET-1[1-32]. Taken together, our data indicate that ozone and particulate matter independently regulate the expression of lung endothelin system genes, but show complex toxicological interaction with respect to plasma ET-1.

Air Pollutants↗

PubMed1990

Associations between morbidity and alternative measures of particulate matter.

This paper explores the association between acute respiratory morbidity and different measures of exposure to airborne particulate matter, including sulfates, total suspended particulates, and fine and inhalable particulates. Regression analysis was used to test for the impacts of these alternative measures of particulate matter on respiratory morbidity using the 1979-1981 annual Health Interview Surveys and EPA's Inhalable Particle Monitoring Network. The general results indicate that, of the surrogate measures for particulate matter, sulfates appear to have the greatest association with morbidity. To the extent that sulfuric acid aerosols are correlated with airborne sulfates, the results suggest that respiratory impairment sufficient to lead to days of reduced activity may be related to the existence of acidity in the air. These findings are consistent with the results of ecological studies reporting an association between mortality and exposures to fine particles and sulfates.

Adult↗

PubMed2006

Characterisation of PM(10), PM(2.5) and benzene soluble organic fraction of particulate matter in an urban area of Kolkata, India.

In this study, the relationship between inhalable particulate (PM(10)), fine particulate (PM(2.5)), coarse particles (PM(2.5 - 10)) and meteorological parameters such as temperature, relative humidity, solar radiation, wind speed were statistically analyzed and modelled for urban area of Kolkata during winter months of 2003-2004. Ambient air quality was monitored with a sampling frequency of twenty-four hours at three monitoring sites located near traffic intersections and in an industrial area. The monitoring sites were located 3-5 m above ground near highly trafficked and congested areas. The 24 h average PM(10) and PM(2.5) samples were collected using Thermo-Andersen high volume samplers and exposed filter papers were extracted and analysed for benzene soluble organic fraction. The ratios between PM(2.5) and PM(10) were found to be in the range of 0.6 to 0.92 and the highest ratio was found in the most polluted urban site. Statistical analysis has shown a strong positive correlation between PM(10) and PM(2.5) and inverse correlation was observed between particulate matter (PM(10) and PM(2.5)) and wind speed. Statistical analysis of air quality data shows that PM(10) and PM(2.5) are showing poor correlation with temperature, relative humidity and solar radiation. Regression equations for PM(10) and PM(2.5) and meteorological parameters were developed. The organic fraction of particulate matter soluble in benzene is an indication of poly aromatic hydrocarbon (PAH) concentration present in particulate matter. The relationship between the benzene soluble organic fraction (BSOF) of inhalable particulate (PM(10)) and fine particulate (PM(2.5)) were analysed for urban area of Kolkata. Significant positive correlation was observed between benzene soluble organic fraction of PM(10) (BSM10) and benzene soluble organic fraction of PM(2.5) (BSM2.5). Regression equations for BSM10 and BSM2.5 were developed.

Air↗

PubMedDate not supplied

The spatial and temporal variation of particulate matter within the home.

Numerous epidemiological studies have found associations between ambient particulate matter and adverse health outcomes. The importance of indoor particles has also been recognised since people spend an average of 90% of their time indoors. In order to better understand exposure to particles this study was carried out to provide data on the characteristics of airborne particulate matter found inside homes in the UK. Forty-eight-h measurements were taken at 10 houses during the summer of 1999. Particulate matter with a 50% cut-off efficiency at an aerodynamic diameter of 2.5 microm (PM2.5) and total suspended particulate (TSP) mass concentrations were measured gravimetrically in the kitchen and living room of each home. Concurrent continuous measurements of particle number concentrations over eight different aerodynamic diameter size ranges were made with an optical particle counter. Occupants were asked to complete a time-activity diary and a short questionnaire relating to various housing characteristics for the 48-h period. The volunteers spent approximately 60% of their time at home indoors. The geometric mean concentration of TSP over the 48 h was 32 microg/m3 in the kitchen and 41 microg/m3 in the living room. The geometric mean concentration of PM2.5 was 13 microg/m3 in the kitchen (integrated over the entire 48-h period) and 12 microg/m3 in the living room (integrated over the time the volunteer was present in the house) with a range of 5 to 77 microg/m3. The continuous measurements showed large variability over the day as a result of activities such as cooking and smoking and the patterns were similar in the kitchen and the living room. A good correlation of both mass and mean number concentration between rooms indicated a high degree of spatial uniformity.

Air Pollution, Indoor↗