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PubMed2004

Determination of levoglucosan in atmospheric fine particulate matter.

A microanalytical method suitable for the quantitative determination of the sugar anhydride levoglucosan in low-volume samples of atmospheric fine particulate matter (PM) has been developed and validated. The method incorporates two sugar anhydrides as quality control standards. The recovery standard sedoheptulosan (2,7-anhydro-beta-D-altro-heptulopyranose) in 20 microL solvent is added onto samples of the atmospheric fine PM and aged for 1 hr before ultrasonic extraction with ethylacetate/ triethylamine. The extract is reduced in volume, an internal standard is added (1,5-anhydro-D-mannitol), and a portion of the extract is derivatized with 10% by volume N-trimethylsilylimidazole. The derivatized extract is analyzed by gas chromatography/mass spectrometry (GC/MS). The recovery of levoglucosan using this procedure was 69 +/- 6% from five filters amended with 2 microg levoglucosan, and the reproducibility of the assay is 9%. The limit of detection is approximately 0.1 microg/mL, which is equivalent to approximately 3.5 ng/m3 for a 10 L/min sampler or approximately 8.7 ng/m3 for a 4 L/min personal sampler (assuming 24-hr integrated samples). We demonstrated that levoglucosan concentrations in collocated samples (expressed as ng/m3) were identical irrespective of whether samples were collected by PM with aerodynamic diameter < or = 2.5 microm or PM with aerodynamic diameter < or = 10 microm impactors. It was also demonstrated that X-ray fluorescence analysis of samples of atmospheric PM, before levoglucosan determinations, did not alter the levels of levoglucosan.

Aerosols↗
PubMed2006

Relation between concentration of air pollution and cause-specific mortality: four-year exposures to nitrogen dioxide and particulate matter pollutants in 470 neighborhoods in Oslo, Norway.

This study investigated the concentration-response relation between air pollution (nitrogen dioxide and particulate matter pollutants PM(10) and PM(2.5)) and cause-specific mortality. The population included all inhabitants of Oslo, Norway, aged 51-90 years on January 1, 1992 (n = 143,842) with follow-up of deaths from 1992 to 1998. An air dispersion model (AirQUIS; Norwegian Institute for Air Research (NILU), Oslo, Norway) was used to estimate levels of exposure in 1992-1995 in all 470 administrative neighborhoods. These data were linked to census, education, and death registries. A consistent effect on all causes of death was found for both sexes and age groups by all indicators of air pollution. The effects appeared to increase at nitrogen dioxide levels higher than 40 micro g/m(3) in the youngest age group and with a linear effect in the interval 20-60 micro g/m(3) for the oldest. An effect of all indicators on cardiovascular causes, lung cancer, and chronic obstructive pulmonary disease was also found in both age groups and sexes. The effects were particularly strong for chronic obstructive pulmonary disease, which appeared to have linear effects, whereas cardiovascular causes and lung cancer seemed to have threshold effects. Results show that vulnerable persons with chronic obstructive pulmonary disease and the elderly seem to be susceptible to air pollution at lower levels than the general population.

Aged↗
PubMed2003

Temporal variation of hydroxyl radical generation and 8-hydroxy-2'-deoxyguanosine formation by coarse and fine particulate matter.

AIMS: To determine the induction of 8-hydroxy-2'-deoxyguanosine (8-OHdG) by fine (<2.5 microm) and coarse (10-2.5 microm) particulate matter (PM) sampled over time at one sampling location, and to relate the observed effects to the hydroxyl radical (*OH) generating activities and transition metal content of these samples, and to meteorological parameters. METHODS: Weekly samples of coarse and fine PM were analysed for H(2)O(2) dependent *OH formation using electron spin resonance (ESR) and formation of 8-OHdG in calf thymus DNA using an immuno-dotblot assay. Immunocytochemistry was used to determine 8-OHdG formation in A549 human epithelial lung cells. To determine temporal effects, samples from six weeks in summer and six weeks in autumn/winter were compared using ESR and the dotblot assay. Concentrations of leachable V, Cr, Fe, Ni, and Cu were determined by inductively coupled plasma mass spectrometry. RESULTS: Both PM fractions elicited *OH generation as well as 8-OHdG formation in calf thymus DNA and in A549 cells. 8-OHdG formation in the naked DNA was significantly related to *OH generation, but not to metal concentrations except for copper. A significantly higher *OH generation was observed for coarse PM, but not fine PM collected during the autumn/winter season; this was not due to differences in sampled mass or metal content. Specific weather conditions under which increased *OH formation in the coarse mode was observed suggest that other, as yet unknown, anthropogenic components might affect the radical generating capacity of PM. CONCLUSIONS: Both coarse and fine PM are able to generate *OH, and induce formation of 8-OHdG. When considered at equal mass, *OH formation shows considerable variability with regard to the fraction of PM, as well as the sampling season. The toxicological implications of this heterogeneity in *OH formation by PM, as can be easily determined by ESR, need further investigation.

Animals↗
PubMed1990

[The suspended particulate matter (SPM) and polycyclic aromatic hydrocarbons (PAHs) in indoor and outdoor air along a main road].

The change in concentration of suspended particulate matter (SPM) in indoor and outdoor air in the Tokyo metropolitan area was studied using a new portable sampler (SPMP-sampler). The relationship between the airborne particle concentration in indoor and outdoor air varied with the aerodynamic diameters of the particles. The concentration of the SPM in indoor air increased in proportion to that in outdoor air. The polycyclic aromatic hydrocarbon (PAH) concentration in SPM also varied with the aerodynamic diameters of the particles. Fine particles with diameters of less than 2 microns contained high concentrations of PAH. The PAH concentration in indoor air increased in proportion to that in outdoor air. There were significant correlations between the concentrations of B(k)F, B(a)P, and B(ghi)P in indoor air. The mutagenic activities in the airborne particles also varied with the aerodynamic diameters of the particles. Fine particles with diameters of less than 2 microns had high mutagenic activities.

Air Pollutants↗
PubMed2006

Lung toxicity of ambient particulate matter from southeastern U.S. sites with different contributing sources: relationships between composition and effects.

BACKGROUND: Exposure to air pollution and, more specifically, particulate matter (PM) is associated with adverse health effects. However, the specific PM characteristics responsible for biological effects have not been defined. OBJECTIVES: In this project we examined the composition, sources, and relative toxicity of samples of PM with aerodynamic diameter </= 2.5 microm (PM2.5) collected from sites within the Southeastern Aerosol Research and Characterization (SEARCH) air monitoring network during two seasons. These sites represent four areas with differing sources of PM2.5, including local urban versus regional sources, urban areas with different contributions of transportation and industrial sources, and a site influenced by Gulf of Mexico weather patterns. METHODS: We collected samples from each site during the winter and summer of 2004 for toxicity testing and for chemical analysis and chemical mass balance-based source apportionment. We also collected PM2.5 downwind of a series of prescribed forest burns. We assessed the toxicity of the samples by instillation into rat lungs and assessed general toxicity, acute cytotoxicity, and inflammation. Statistical dose-response modeling techniques were used to rank the relative toxicity and compare the seasonal differences at each site. Projection-to-latent-surfaces (PLS) techniques examined the relationships among sources, chemical composition, and toxicologic end points. RESULTS AND CONCLUSIONS: Urban sites with high contributions from vehicles and industry were most toxic.

Air Movements↗
PubMed2005

Continuous determination of fine particulate matter mass in the Salt Lake City Environmental Monitoring project: a comparison of real-time and conventional TEOM monitor results.

Fine particulate matter (PM2.5) mass was determined on a continuous basis at the Salt Lake City Environmental Protection Agency Environmental Monitoring for Public Awareness and Community Tracking monitoring site in Salt Lake City, UT, using three different monitoring techniques. Hourly averaged PM2.5 mass data were collected during two sampling periods (summer 2000 and winter 2002) using a real-time total ambient mass sampler (RAMS), sample equilibration system (SES)-tapered element oscillating microbalance (TEOM), and conventional TEOM monitor. This paper compares the results obtained from the various monitoring systems, which differ in their treatment of semivolatile material (SVM; particle-bound water, semivolatile ammonium nitrate, and semivolatile organic compounds). PM2.5 mass results obtained by the RAMS were consistently higher than those obtained by the SES-TEOM and conventional TEOM monitors because of the RAMS ability to measure semivolatile ammonium nitrate and semivolatile organic material but not particle-bound water. The SES-TEOM monitoring system was able to account for an average of 28% of the SVM, whereas the conventional TEOM monitor loses essentially all of the SVM from the single filter during sampling. Occasional mass readings by the various TEOM monitors that are higher than RAMS results may reflect particle-bound water, which, under some conditions, is measured by the TEOM but not the RAMS.

Air Pollutants↗
PubMed2004

The role of nitric oxide in the particulate matter (PM2.5)-induced NFkappaB activation in lung epithelial cells.

NFkappaB is one of key transcription factors that are involved in the inflammatory responses to the particulate matter (PM) in the lungs. In order to further understand the molecular mechanism, the effects of antioxidants and an inducible nitric oxide synthase (iNOS) inhibitor on PM-induced NFkappaB activation were examined in A549 lung epithelial cells. NFkappaB activation by 2.5 microm particulates (PM2.5) was evident from the degradation of an NFkappaB inhibitory protein, IkappaBalpha, and a luciferase reporter assay for NFkappaB activity. In these experiments, a pre-treatment of the cells with antioxidants N-acetyl-l-cysteine (NAC) and dimethylthiourea (DMTU) or an iNOS inhibitor l-N6-1-iminoethyl-lysine (L-NIL) clearly inhibited the NFkappaB activation by PM2.5. The inhibitory effect of L-NIL was also observed on the PM2.5-induced interleukin-8 (IL-8) gene expression both at the transcriptional and protein levels. These results suggest that PM2.5 induces NFkappaB activity via the pathways involving ROS and/or RNS generation. Considering the fact that NFkappaB also induces NO generation via iNOS expression, they might make a positive feedback loop that amplifies the downstream responses.

Air Pollutants↗
PubMed2002

PAH levels and profiles in the suspended particulate matter in Zagreb through four seasons.

This paper presents the analysis of polycyclic aromatic hydrocarbons (PAHs) measured in all four seasons in suspended particulate matter (SPM) collected with a high-volume sampler on one measuring site in the northern part of Zagreb. About 30 samples of SPM were analysed for each season, including workdays and weekends and there were no differences amongst them. The concentrations of all PAHs were highest in winter and lowest in summer. The spring PAH concentrations were lower than the autumn ones, as the spring had more sunny and warm days. The profiles of PAH/BaP at the measurement sites showed that the main source of PAHs in spring and summer was traffic while a substantial amount of autumn and winter PAHs, besides traffic, came from heating.

Air Pollutants↗
PubMed1985

Partition and determination of cadmium, copper, lead and zinc in marine suspended particulate matter.

A method for the determination of Cd, Cu, Pb, and Zn in the total and acetic acid (25%) soluble fraction of suspended particulate matter collected on Nuclepore membranes is described. The acetic acid leaching was carried out in a modified Millipore vacuum filtration apparatus. The total sample and the acetic insoluble fraction were decomposed in teflon bombs with HF/aqua regia. Flame or graphite furnace AAS was used for metal determinations. Sequential acetic acid extractions (3) show that on the average 76.4-92.0% of the metals are removed with the first extraction. Cadmium is potentially most easily available to biota with 90.4% of the total metal concentration located in the acetic acid soluble fraction.

Cadmium↗
PubMed2005

Effects of airborne fine particulate matter on antioxidant capacity and lipid peroxidation in multiple organs of rats.

The purpose of this research was to determine whether airborne fine particulate matter (PM(2.5)) could increase levels of lipid peroxidation and alter intracellular redox status in multiple organs of rats. Thirty-two male Wistar rats were randomly divided into the treated groups using PM(2.5) at different dosages (1.5, 7.5, 37.5 mg/kg) and with a control group using saline. Rats were sacrificed 24 h after one-time intratracheal instillation. Then we investigated the activities of Cu, Zn-superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), and the levels of glutathione (GSH) and thiobarbituric acid-reactive substances (TBARS) in hearts, livers, spleens, lungs, kidneys, brains, and testicles. It was found that PM(2.5) at dosages of 7.5 and 37.5 mg/kg significantly increased lipid peroxidation levels in the hearts, livers, lungs, and testicles, decreased SOD, CAT, and GPx activities in the lungs, livers, kidneys, and brains, and depleted GSH levels in all the measured organs compared to the control. There were also differences in the changes of antioxidative enzymes activities and lipid peroxidation levels in seven organs. These results led to a conclusion that airborne PM(2.5) was a systemic toxic agent, not only to respiratory and cardiovascular systems. Its toxic effects might be attributed to oxidative damage mediated by prooxidant/antioxidant imbalance or excess free radicals. Further work is required to explain the toxicity role of PM(2.5) on multiple organs of mammals.

Administration, Inhalation↗
PubMed2003

Exposure assessment of particulate matter for susceptible populations in Seattle.

In this article we present results from a 2-year comprehensive exposure assessment study that examined the particulate matter (PM) exposures and health effects in 108 individuals with and without chronic obstructive pulmonary disease (COPD), coronary heart disease (CHD), and asthma. The average personal exposures to PM with aerodynamic diameters < 2.5 microm (PM2.5) were similar to the average outdoor PM2.5 concentrations but significantly higher than the average indoor concentrations. Personal PM2.5 exposures in our study groups were lower than those reported in other panel studies of susceptible populations. Indoor and outdoor PM2.5, PM10 (PM with aerodynamic diameters < 10 microm), and the ratio of PM2.5 to PM10 were significantly higher during the heating season. The increase in outdoor PM10 in winter was primarily due to an increase in the PM2.5 fraction. A similar seasonal variation was found for personal PM2.5. The high-risk subjects in our study engaged in an equal amount of dust-generating activities compared with the healthy elderly subjects. The children in the study experienced the highest indoor PM2.5 and PM10 concentrations. Personal PM2.5 exposures varied by study group, with elderly healthy and CHD subjects having the lowest exposures and asthmatic children having the highest exposures. Within study groups, the PM2.5 exposure varied depending on residence because of different particle infiltration efficiencies. Although we found a wide range of longitudinal correlations between central-site and personal PM2.5 measurements, the longitudinal r is closely related to the particle infiltration efficiency. PM2.5 exposures among the COPD and CHD subjects can be predicted with relatively good power with a microenvironmental model composed of three microenvironments. The prediction power is the lowest for the asthmatic children.

Age Factors↗
PubMed2002

Elevation of serum endothelins and cardiotoxicity induced by particulate matter (PM2.5) in rats with acute myocardial infarction.

Epidemiological studies have defined a significant positive association of acute exposure to ambient concentrations of particulate matter (PM) with increased daily mortality and hospital admission for cardiovascular diseases. Experimental studies have shown that animals with pre-existing cardiovascular diseases are more susceptible to the cardiac effect of PM exposure. The present study was undertaken to investigate possible involvement of upregulation of the endothelin system in PM exposure-induced cardiotoxicity in rats with acute myocardial infarction (MI). Adult male Sprague Dawley rats were subjected to occlusion of the left coronary artery and displayed myocardial infarction 12 h after the surgery. The heart rate significantly decreased and premature ventricular complexes of the electrocardiogram occurred in the myocardial infarct animals. Exposure to PM(2.5) via intratracheal instillation with 2.0 mg in 0.3 mL normal saline significantly worsened the ventricular arrhythmia along with a further decrease in heart rate. The same PM exposure only caused slight cardiac changes in the sham-operated animals. Serum total endothelin concentrations were significantly elevated in both myocardial infarct rats and shamoperated controls in response to PM exposure. However, increased numbers of the endothelin receptor type A on the cardiomyocytes were observed only in the infarct myocardium. This study thus suggests that upregulation of the endothelin system in rats with MI is likely involved in the PM exposure-induced cardiotoxicity.

Administration, Inhalation↗
PubMed2006

Demolition of high-rise public housing increases particulate matter air pollution in communities of high-risk asthmatics.

Public housing developments across the United States are being demolished, potentially increasing local concentrations of particulate matter (PM) in communities with high burdens of severe asthma. Little is known about the impact of demolition on local air quality. At three public housing developments in Chicago, IL, PM with an aerodynamic diameter < 10 microm (PM10) and < 2.5 microm were measured before and during high-rise demolition. Additionally, size-selective sampling and real-time monitoring were concurrently performed upwind and downwind of one demolition site. The concentration of particulates attributable to demolition was estimated after accounting for background urban air pollution. Particle microscopy was performed on a small number of samples. Substantial increases of PM10 occurred during demolition, with the magnitude of that increase varying based on sampler distance, wind direction, and averaging time. During structural demolition, local concentrations of PM10 42 m downwind of a demolition site increased 4- to 9-fold above upwind concentrations (6-hr averaging time). After adjusting for background PM10, the presence of dusty conditions was associated with a 74% increase in PM10 100 m downwind of demolition sites (24-hr averaging times). During structural demolition, short-term peaks in real-time PM10 (30-sec averaging time) occasionally exceeded 500 microg/m(3). The median particle size downwind of a demolition site (17.3 microm) was significantly larger than background (3 microm). Specific activities are associated with realtime particulate measures. Microscopy did not identify asbestos or high concentrations of mold spores. In conclusion, individuals living near sites of public housing demolition are at risk for exposure to high particulate concentrations. This increase is characterized by relatively large particles and high short-term peaks in PM concentration.

Air Pollutants↗
PubMed2006

Identification of polycyclic aromatic hydrocarbons (PAHs) in suspended particulate matter by synchronous fluorescence spectroscopic technique.

The synchronous fluorescence (SF) technique has been used in the identification of polycyclic aromatic hydrocarbons (PAHs) from air particulate sample in an urban environment of Delhi, Jawaharlal Nehru University. Suspended particulate matter samples of 24h duration were collected on glass fiber filter papers. PAHs were extracted from the filter papers using dichloromethane (DCM)+hexane with ultrasonication method. Qualitative measurements of the polycyclic aromatic hydrocarbons (PAHs) were carried out using the SF technique at various wavelength intervals (Deltalambda). Due to the difference in chemical structure, each PAH gives specific characteristic spectrum for each Deltalambda. Following PAHs were detected in our measurement: benz(a)anthracene (BaA), pyrene (Pyr), chrysene (Chry), fluoranthene (Flan), phenanthrene (Phen), and benz(ghi)perylene (BghiP). This is in agreement with our earlier work for determination of these PAHs using gas chromatography (GC). The seasonal variation of the PAHs was found to be maximum in winter and minimum during the monsoon.

Air Pollutants↗
PubMed2003

Polybrominated diphenyl ethers in influents, suspended particulate matter, sediments, sewage treatment plant and effluents and biota from the Netherlands.

Polybrominated diphenyl ethers (PBDEs) have been determined in 133 samples of suspended particulate matter (SPM), sediments, sewage treatment plant (STP) influents and effluents, fish and mussels from various locations in The Netherlands, as a part of a large Dutch national study on estrogenic contaminants in the aquatic environment (LOES project). Some PBBs were also analysed but not found in any of the samples at detectable levels. PBDEs and PBBs were included in this study because indications of long term effects on the balance of endocrine systems were found in the literature. High concentrations of decaBDE (up to 4600 g/kg dry weight) were found in SPM from the Western Scheldt. These levels are possibly related to spillage during use of PBDEs in industries upstream the river Scheldt in Belgium. SPM was identified as an important carrier for higher brominated diphenyl ethers in the aquatic environment. DecaBDE was not found at detectable levels in flounder, bream and mussels. The bioaccumulation of decaBDE in these fish and shellfish samples is apparently limited. Lower brominated PBDE congeners (tetra/penta) were also found in the Western Scheldt as well as in the Rhine delta and the river Meuse, but in much lower concentrations than the decaBDE. In contrast with decaBDE, the tetra and pentaBDEs were found in biota. It was concluded that at least a small part of the PBDE can pass STPs.

Animals↗
PubMed2002

Indoor particulate matter of outdoor origin: importance of size-dependent removal mechanisms.

Adverse human health effects have been observed to correlate with levels of outdoor particulate matter (PM), even though most human exposure to PM of outdoor origin occurs indoors. In this study, we apply a model and empirical data to explore the indoor PM levels of outdoor origin for two major building types: offices and residences. Typical ventilation rates for each building type are obtained from the literature. Published data are combined with theoretical analyses to develop representative particle penetration coefficients, deposition loss rates, and ventilation-system filter efficiencies for a broad particle size range (i.e., 0.001-10 microm). We apply archetypal outdoor number, surface area, and mass PM size distributions for both urban and rural airsheds. We also use data on mass-weighted size distributions for specific chemical constituents of PM: sulfate and elemental carbon. Predictions of the size-resolved indoor proportion of outdoor particles (IPOP) for various conditions and ambient particle distributions are then computed. The IPOP depends strongly on the ambient particle size distribution, building type and operational parameters, and PM metric. We conclude that an accurate determination of exposure to particles of ambient origin requires explicit consideration of how removal processes in buildings vary with particle size.

Air Movements↗
PubMed2005

Ambient gas concentrations and personal particulate matter exposures: implications for studying the health effects of particles.

BACKGROUND: Data from a previous study conducted in Baltimore, MD, showed that ambient fine particulate matter less than 2.5 mum in diameter (PM2.5) concentrations were strongly correlated with corresponding personal PM2.5 exposures, whereas ambient O3, NO2, and SO2 concentrations were weakly correlated with their personal exposures to these gases. In contrast, many of the ambient gas concentrations were reasonable surrogates of personal PM2.5 exposures. METHODS: Personal multipollutant exposures and corresponding ambient air pollution concentrations were measured for 43 subjects living in Boston, MA. The cohort consisted of 20 healthy senior citizens and 23 schoolchildren. Simultaneous 24-hour integrated PM2.5, O3, NO2, and SO2 personal exposures and ambient concentrations were measured. All PM2.5 samples were also analyzed for SO4 (sulfate). We analyzed personal exposure and ambient concentration data using correlation and mixed model regression analyses to examine relationships among (1) ambient PM2.5 concentrations and corresponding ambient gas concentrations; (2) ambient PM2.5 and gas concentrations and their respective personal exposures; (3) ambient gas concentrations and corresponding personal PM2.5 exposures; and (4) personal PM2.5 exposures and corresponding personal gas exposures. RESULTS: We found substantial correlations between ambient PM2.5 concentrations and corresponding personal exposures over the course of time. Additionally, our results support the earlier finding that summertime gaseous pollutant concentrations may be better surrogates of personal PM2.5 exposures (especially personal exposures to PM2.5 of ambient origin) than they are surrogates of personal exposures to the gases themselves. CONCLUSIONS: Particle health effects studies that include both ambient PM2.5 and gaseous concentrations as independent variables must be analyzed carefully and interpreted cautiously, since both parameters may be serving as surrogates for PM2.5 exposures.

Aged↗