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PubMed2001

Sampling and analysis of gaseous pollutants and related particulate matter in a Mediterranean site: Antalya-Turkey.

Gas phase pollutants. nitric acid (HNO3), sulfur dioxide (SO2), ammonia (NH3) and particulate matter, were collected simultaneously for six months from the Eastern Mediterranean atmosphere (Küçük Calticak, Antalya) using a "filter pack" system developed in our laboratory. This system is a combination of chemically treated filters for the collection of gaseous ammonia and sulfur dioxide. and Teflon and nylon filters for the collection of particulate matter and gaseous nitric acid, respectively. After pre-treatment, Teflon, nylon and the treated filters were analyzed by ion chromatography (IC) for major ionic species: SO4(2-) NO3- and Cl, and by colorimetry for NH4+ ion. Comparison of the SRM (Standard Reference Material) results with measured concentrations showed a good precision for the IC analyses: 3%, 1% and 2% for Cl-, NO3 and SO4(2-) ions. respectively. Most of the measured parameters were log-normally distributed. Chloride ion had the highest (4.30 microg m(-3) and HNO3 had the lowest (0.42 microg m(-3)) concentrations. Total acidity in the Eastern Mediterranean is controlled by 47.7% HNO3 and 52.8% by H2SO4. Ammonium, nss-SO4(2-) (non-sea salt sulfate) and NO3 did not show a strong correlation, (r = 0.4), which means that ammonia is not the major neutralizing species in the Eastern Mediterranean atmosphere.

Air Pollutants↗

PubMed1985

Determination of 23 polycyclic aromatic hydrocarbons in atmospheric particulate matter of the Paris area and photolysis by sunlight.

Twenty-three polycyclic aromatic hydrocarbons (PAH) were determined in atmospheric particulate matter in 4 places of the Paris area at several times of the year. Fractionation was performed by reversed-phase high-pressure liquid chromatography. Determination was done by recording emission or excitation fluorescence spectra via a stopped-flow technique. Triphenylene was also extemporaneously determined by its phosphorescence spectrum at low temperature. Among the PAH determined dibenz(e,ghi)perylene has not been detected before in atmospheric particulate matter. The 10 more abundant PAH ranged from 0.1 to 40 ng/m3 of filtered air. Concentrations in August are from 14 to 250 times less than in January depending on the PAH. The reasons for this difference of behaviour among the PAH were investigated with regard to their photochemical and non-photochemical reactivity.

Air Pollutants↗

PubMed1977

[Determination of the acidity of particulate matter in the urban and industrial atmospheres].

A new method is described for the determination of the strong acidity of particulate matter. The method consists in the volumetric titration of an aqueous extract by means of a strong acid. The titration is performed potentiometrically using a glass electrode and the end point is obtained by extrapolation using a Gran's plot. The lowest concentration of strong acid detectable in a sample is about 0.5 microgram/ml expressed as H2SO4. The method has been applied for the determination of the strong acidity content in airborne particulate matter samples and in dusts emitted from industrial sources.

Acids↗

PubMed2005

Weight of the evidence or wait for the evidence? Protecting underground miners from diesel particulate matter.

A coalition of mine operators has used a variety of tactics to obstruct scientific inquiry and impede public health action designed to protect underground miners from diesel particulate matter. These workers are exposed to the highest level of diesel particulate matter compared with any other occupational group. This case study profiles a decade-long saga of the Methane Awareness Resource Group Diesel Coalition to impede epidemiological studies on diesel exhaust undertaken by the National Institute for Occupational Safety and Health and the National Cancer Institute, and to derail a health standard promulgated by the Mine Safety and Health Administration. The case study highlights the coalition's mastery of legislative, judicial, and executive branch operations and the reaction of policymakers.

Air Pollutants, Occupational↗

PubMed2002

A role for associated transition metals in the immunotoxicity of inhaled ambient particulate matter.

Epidemiologic studies demonstrate that infection, specifically pneumonia, contributes substantially to the increased morbidity and mortality among elderly individuals following exposure to ambient particulate matter (PM). This laboratory has previously demonstrated that a single inhalation exposure of Streptococcus pneumoniae-infected rats to concentrated ambient PM(2.5) (particulate matter with aerodynamic diameter < or =2.5 microm) from New York City (NYC) air exacerbates the infection process and alters pulmonary and systemic immunity. Although these results provide some basis for explaining the epidemiologic findings, the identity of specific PM constituents that might have been responsible for the worsening pneumonia in exposed hosts remains unclear. Thus, studies were performed to correlate the physicochemical attributes of ambient PM(2.5) with its in vivo immunotoxicity to identify and characterize the role of constitutive transition metals in exacerbating an ongoing streptococcal infection. Uninfected or previously infected rats were exposed in the laboratory to soluble divalent Fe, Mn, or Ni chloride salts. After exposure, uninfected rats were sacrificed and their lungs were lavaged. Lungs from infected hosts were used to evaluate changes in bacterial clearance and effects of exposure on the extent/severity of infection. Results demonstrated that inhalation of Fe altered innate and adaptive immunity in uninfected hosts, and both Fe and Ni reduced pulmonary bacterial clearance in previously infected rats. The effects on clearance produced in infected Fe-exposed rats were similar to those seen in infected rats exposed to ambient NYC PM. Taken together, these studies demonstrate that inhaled ambient PM can worsen the outcome of an ongoing pulmonary infection and that associated Fe may play some role in the immunotoxicity.

Animals↗

PubMed2002

Particulate matter and lung function growth in children: a 3-yr follow-up study in Austrian schoolchildren.

The effects of particulate matter <10 microm in diameter (PM10) and other air pollutants on lung function were assessed in 975 schoolchildren, from eight communities in Lower Austria between 1994-1997. In each community, air pollution data were collected. Spirometry was performed twice a year. PM10 concentration (mean concentration between two subsequent lung-function measures in spring and autumn (summer interval) or between autumn and spring (winter interval)) showed a mean value of 17.36 microg x m(-3) in the summer interval and 21.03 microg m(-3) in the winter interval. A slower increase in the forced expiratory volume in one second (FEV1) and midexpiratory flow between 25 and 75% of the forced vital capacity (MEF25-75) with age in children exposed to higher summer PM10 was observed in the 3-yr study period. After adjusting for potential confounders (sex, atopy, passive smoking, initial height, height difference, site, initial lung function) an increase of summer PM10 by 10 microg x m(-3) was associated with a decrease in FEV1 growth of 84 mL x yr(-1) and 329 mL x s(-1) x yr(-1) for MEF25-75. Nitrogen dioxide and ozone also showed a negative effect on lung-function growth, confirming previous work. The authors concluded that long-term exposure to particulate matter <10 microm in diameter had a significant negative effect on lung-function proxy for the development of large (forced expiratory volume in one second) and small (midexpiratory flow between 25 and 75% of the forced vital capacity) airways, respectively, with strong evidence for a further effect of ozone and nitrogen dioxide on the development of forced vital capacity and forced expiratory volume in one second.

Air Pollutants↗

PubMed1999

A new model rat with acute bronchiolitis and its application to research on the toxicology of inhaled particulate matter.

The aim of the present study was to establish a useful animal model that simulates humans sensitive to inhaled particulate matter (PM). We have developed a new rat model of acute bronchiolitis (Br) by exposing animals to NiCl2 (Ni) aerosols for five days. Three days following the Ni exposure, the animals developed signs of tachypnea, mucous hypersecretion, and bronchiolar inflammation which seemed to progress quickly during the fourth to fifth day. They recovered from lesions after four weeks in clean air. To assess the sensitivity of the Br rats to inhaled particles, two kinds of PM of respirable size were tested with doses similar to or a little higher to the recommended threshold limit values (TLVs) for the working environment in Japan. Titanium dioxide (TiO2 = Ti) was chosen as an inert and insoluble particles and vanadium pentoxide (V2O5 = V), as a representative soluble and toxic airborne material. The Br rats exposed to either Ti or V were compared the pathological changes in the lungs and the clearance of particles to those in normal control or Br rats kept in clean air. The following significant differences were observed in Br rats: 1. delayed recovery from pre-existing lesions or exacerbated inflammation, 2. reductions in deposition and clearance rate of inhaled particles with the progress of lesions. The present results suggest that Br rats are more susceptible to inhaled particles than control rats. Therefore, concentrations of particulate matter lower than the TLVs for Japan, which have no harmful effects on normal lungs, may not always be safe in the case of pre-existing lung inflammation.

Acute Disease↗

PubMed2006

Ambient particulate matter directs nonclassic dendritic cell activation and a mixed TH1/TH2-like cytokine response by naive CD4+ T cells.

BACKGROUND: Dendritic cells (DCs) translate environmental cues into T-cell activating signals, and are centrally involved in allergic airway inflammation. Ambient particulate matter (APM) is ubiquitous and associated with allergic diseases, but it is unknown whether APM directly activates DCs. OBJECTIVE: To study comprehensively the effects of APM on myeloid DC phenotype and function. METHODS: Development of DC was modeled using human CD34(+) progenitor cells. APM was collected from ambient outdoor air in Baltimore city. We studied the effects of APM on DC activation in vitro, compared with LPS. RESULTS: Ambient particulate matter enhanced DC expression of costimulatory receptors but suppressed the expression of both the endocytosis receptor CD206 and uptake of fluorescein isothiocyanate-conjugated dextran. The expression of the Toll-like pattern-recognition receptors Toll-like receptor 2 and Toll-like receptor 4 was also blunted. APM-exposed DCs secreted less IL-12 and IL-6 but exhibited increased secretion of IL-18 and IL-10 compared with LPS stimulation. A T(H)2-like pattern of cytokine production was seen in cocultures of APM-stimulated DCs and alloreactive naive CD4(+) T cells where the IL-13 to IFN-gamma ratio was reversed. This contrasted with the T(H)1 polarizing effects of LPS on DCs. CONCLUSION: We report for the first time that APM-exposed DCs direct a complex T(H)1/T(H)2-like pattern of T-cell activation by mechanisms that involve nonclassic activation of DCs. CLINICAL IMPLICATIONS: Inhaled APM can act directly on DCs as a danger signal to direct a proallergic pattern of innate immune activation.

Antigen Presentation↗

PubMed2005

Association between particulate matter and emergency room visits, hospital admissions and mortality in Spokane, Washington.

There is conflicting evidence regarding the association between different size fractions of particulate matter (PM) and cardiac and respiratory morbidity and mortality. We investigated the short-term associations of four size fractions of particulate matter (PM(1), PM(2.5), PM(10), and PM(10-2.5)) and carbon monoxide with hospital admissions and emergency room (ER) visits for respiratory and cardiac conditions and mortality in Spokane, Washington. We used a log-linear generalized linear model to compare daily averages of PM and carbon monoxide with daily counts of the morbidity and mortality outcomes from January 1995 to June 2001. We examined pollution lags ranging from 0 to 3 days and compared our results to a similar log-linear generalized additive model. Effect estimates tended to be smaller and have larger standard errors for the generalized linear model. Overall, we saw no association with respiratory ER visits and any size fraction of PM. However, there was a suggestion of greater respiratory effect from fine PM when compared to coarse fraction. Carbon monoxide was associated with both all respiratory ER visits and visits for asthma at the 3-day lag. We feel that carbon monoxide may be serving as a marker for combustion-derived pollutants, which is one large component of the diverse air pollutant mixture. We also found no association with any size fraction of PM or CO with cardiac hospital admissions or mortality at the 0- to 3-day lag. We found no consistent associations between any size fraction of PM and cardiac or respiratory ER visits or hospital admissions.

Air Pollutants↗

PubMedDate not supplied

Metal content in river suspended particulate matter: data on Po River.

The present study summarizes the last ten years of literature on heavy metal distribution in Suspended Particulate Matter (SPM) and dissolved phase in the Po River (Italy). The work compares different methodologies employed to collect, concentrate and fractionate the samples. The importance of metal speciation as a function of particle size is underlined and two approaches to metal speciation in the colloidal fraction of Po River SPM are presented: Sedimentation Field-Flow Fractionation (SdFFF) and pH-dependent extractions. Finally, emphasis is placed on the need for comparison with a reference "natural background level" of the metal load in Po River particulate matter in order to determine the real human contribution to river pollution. The high values of some trace transition elements, such as Cr and Ni, have been compared with clay sediments around Ferrara and with bricks in historic buildings. The highly comparable natural concentration of these metals in Po fine sedimentary rocks and in historic brick buildings of Ferrara (XII-XVI centuries) can provide information on natural geochemical anomalies.

Environmental Monitoring↗

PubMed1983

Survey of total and respirable suspended particulate matter in an iron foundry. Comparison of stationary sampling and personal monitoring.

In the workshop of an iron foundry total and respirable suspended particulate matter was collected. The performances of (1) filtration systems with 47 mm membrane filters, (2) Andersen cascade impactors, and (3) personal total or respirable monitoring, were compared at a position away from intense sources of particulate debris. Using 15 stationary samplers a survey was made of the particulate levels in the workshop, over a period of 2 weeks. Very large concentration gradients and concentration variations as a function of time were measured for total suspended particulate matter. In the three major source areas, i.e. the pouring department, the core-making department and the shake-out department, special studies were performed to compare stationary and personal monitoring. In the immediate vicinity of intense point sources of coarse particles, such as core-making or shake-out, stationary sampling cannot be used to estimate the personal exposure to total suspended particulates. For respirable particles, however, one or two well-situated stationary size-selective samplers can provide a good estimate of the personal exposure as measured with a personal respirable monitor. The differences found are in the order of 10-20%.

Air Pollutants, Occupational↗

PubMed2006

Quality-assured measurements of animal building emissions: particulate matter concentrations.

Federally funded, multistate field studies were initiated in 2002 to measure emissions of particulate matter (PM) < 10 microm (PM10) and total suspended particulate (TSP), ammonia, hydrogen sulfide, carbon dioxide, methane, nonmethane hydrocarbons, and odor from swine and poultry production buildings in the United States. This paper describes the use of a continuous PM analyzer based on the tapered element oscillating microbalance (TEOM). In these studies, the TEOM was used to measure PM emissions at identical locations in paired barns. Measuring PM concentrations in swine and poultry barns, compared with measuring PM in ambient air, required more frequent maintenance of the TEOM. External screens were used to prevent rapid plugging of the insect screen in the PM10 preseparator inlet. Minute means of mass concentrations exhibited a sinusoidal pattern that followed the variation of relative humidity, indicating that mass concentration measurements were affected by water vapor condensation onto and evaporation of moisture from the TEOM filter. Filter loading increased the humidity effect, most likely because of increased water vapor adsorption capacity of added PM. In a single layer barn study, collocated TEOMs, equipped with TSP and PM10 inlets, corresponded well when placed near the inlets of exhaust fans in a layer barn. Initial data showed that average daily mean concentrations of TSP, PM10, and PM2.5 concentrations at a layer barn were 1440 +/- 182 microg/m3 (n = 2), 553 +/- 79 microg/m3 (n = 4), and 33 +/- 75 microg/m3 (n = 1), respectively. The daily mean TSP concentration (n = 1) of a swine barn sprinkled with soybean oil was 67% lower than an untreated swine barn, which had a daily mean TSP concentration of 1143 +/- 619 microg/m3. The daily mean ambient TSP concentration (n = 1) near the swine barns was 25 +/- 8 microg/m3. Concentrations of PM inside the swine barns were correlated to pig activity.

Air Pollutants↗

PubMed2001

Monitoring of 1-min personal particulate matter exposures in relation to voice-recorded time-activity data.

Recent studies on the association between exposures to airborne particulate matter (PM) and disease have identified short-term peaks in PM exposures as posing especial health threats. Lightweight personal instruments are needed to characterize short-term exposures to PM and to identify the most important sources of high PM excursions. In this study, we measured exposure to fine PM using a small personal nephelometer (pDR; MIE, Inc) to investigate the utility of this instrument in identifying activities and microenvironments most associated with high PM exposures and the magnitude and duration of peaks in PM exposures. Ten adult volunteers wore a pDR recording PM concentrations at 1-min time intervals for 1 week each. PM concentrations were measured by the pDR in units of microg/m(3) based on light scatter. The use of a time-stamped voice recorder enabled activity and location to be continuously documented in real time. In addition, a small, inexpensive light intensity logger was affixed to the pDR to evaluate the potential of this instrument to assist in verifying wearer- recorded data. For each person, patterns of PM exposure were remarkably consistent over daily activities and showed large excursions associated with specific indoor and outdoor microenvironments and activities, such as cooking. When the magnitude and duration of excursions in PM were analyzed, we found that high PM levels occurred in relatively few of the minutes measured but comprised a substantial fraction of the total exposure to PM. Fifteen-minute averaged PM levels were found to be as much as 10 times the daily average. When the data were analyzed with a generalized estimating equation model to account for effects of autocorrelation and clustering, PM exposure was significantly higher during subject-reported events including barbeque, yard work, being near pets or construction activities, cooking, and environmental tobacco smoke exposure, as compared with periods with no pollution events. When light intensity data were explored to determine whether these loggers could be of potential use in establishing or verifying indoor vs outdoor location for future PM studies, we found that personal light intensity measurements differed among indoor, outdoor, and in-car environments (P<0.001). Overlap between measured values implies that light intensity cannot be used to absolutely predict location; however, a sudden increase or decrease in light intensity was highly associated with participant report of location change between indoors and outdoors. This study demonstrates the utility of the pDR in identifying patterns of personal exposures to particulate matter and especially in registering the magnitude and duration of excursions in PM in relation to location and activity.

Activities of Daily Living↗

PubMed2003

Lipid composition of suspended particulate matter (SPM) in a southeastern blackwater stream.

Suspended particulate matter (SPM) was collected seasonally for 1 yr at third- and fifth-order sites in a blackwater stream on the coastal plain in South Carolina. Fatty acids with carbon chain lengths from C(12)-C(32) were the most abundant component among the lipid classes examined with total concentrations varying from 8.5 to 60.2 microgL(-1). Unsaturated fatty acids predominated while significant concentrations of the even-chained saturated components C(24)-C(30) derived from cuticular plant waxes were also found. Concentrations of aliphatic alcohols, with carbon chain lengths between C(16) and C(30), ranged from 0.52 to 2.73 microgL(-1) and was dominated by the higher molecular weight compounds (C(22)-C(30)) derived primarily from cuticular plant waxes. Total hydrocarbon concentrations ranged from 0.35 to 5.66 microgL(-1) and showed no discernible trends with time or consistent difference between sites. The hydrocarbon assemblage observed indicates that these components are entirely of biogenic origin with no detectable anthropogenic contribution. The ratios of unsaturated to saturated fatty acids and cuticular to noncuticular fatty acids and alcohols at both stream locations indicate that the organic detritus associated with SPM collected during November and January is of more recent origin and less processed than that collected in the spring and summer months. Lipid concentrations at the third-order site generally had higher and more variable concentrations of the lipid classes compared with the fifth-order site. The ratio of saturated to unsaturated fatty acids was higher at the third-order site indicating that the organic fraction of SPM at this site was of more recent origin and less decomposed. The ratios of cuticular to noncuticular fatty acids and alcohols support this conclusion. These results indicate an export of particulate lipids of higher carbon resource quality from upstream to lower stream reaches.

Fatty Acids↗

PubMed1995

Bioassay-directed chemical analysis of genotoxic components in urban airborne particulate matter from Barcelona (Spain).

Organic extracts of airborne particulate matter, collected in the city of Barcelona, were subjected to three-level, bioassay-directed, chemical fractionation, including gel permeation chromatography (GPC) and normal-phase (NP) and reversed-phase (RP) liquid chromatography (LC). The chemical characterization, directed by the Salmonella microsome mutagenicity assay (TA98, TA98NR and TA98/1,8DNP6 +/- S9), was carried out by capillary GC (CGC) coupled to selective detection systems, and by GC-MS techniques. The results obtained with the nitroreductase deficient strains show the important contribution of nitroaromatic compounds. Detailed chemical analysis of the mutagenic fractions led to the identification of 82 aromatic compounds and revealed the large contribution of chemical classes that are more polar than polycyclic aromatic hydrocarbons such as aromatic ketones, quinones and aldehydes.

Air Pollutants↗

PubMed1987

The cadmium and lead content of suspended particulate matter emitted from a U.K. refuse incinerator.

Suspended particulate matter (SPM), sampled from the stack of a large refuse incinerator in the U.K., contained markedly elevated levels of Cd (approximately 1600 micrograms g-1) and Pb (approximately 3%). These values were similar to those previously reported for several other incinerators in Europe, but the Pb concentrations were lower than in the SPM from three American incinerators. Calculation of the metal concentration ratio SPM/fly ash for the U.K. incinerator revealed a three-fold enrichment of the two metals on the SPM. Similar ratios were obtained for several other European incinerators; this correspondence in metal partitioning was linked to the use of electrostatic precipitators in these facilities. The SPM metal data obtained in this study were used to estimate atmospheric emissions of 0.5 t Cd year-1 and 11 t Pb year-1 from the incinerator. Extrapolation of the Cd and Pb emission factors derived from this study to the quantity of refuse incinerated in the U.K. results in atmospheric discharges of 6 t Cd year-1 and 115 t Pb year-1. These estimates are in good agreement with those previously reported by an emissions inventory which identified incineration as the single largest source of airborne Cd in the U.K.

Air Pollutants↗

PubMed2005

Hydroxyl-radical-dependent DNA damage by ambient particulate matter from contrasting sampling locations.

Exposure to ambient particulate matter (PM) has been reported to be associated with increased respiratory, cardiovascular, and malignant lung disease. Previously we have shown that PM can induce oxidative DNA damage in A549 human lung epithelial cells. The aims of the present study were to investigate the variability of the DNA-damaging properties of PM sampled at different locations and times and to relate the observed effects to the hydroxyl-radical (OH)-generating activities of these samples. Weekly samples of coarse (10-2.5 microm) and fine (<2.5 microm) PM from four sites (Nordrheim Westfalen, Germany) were analyzed for hydrogen-peroxide-dependent OH formation using electron paramagnetic resonance and formation of 8-hydroxydeoxyguanosine (8-OHdG) in calf thymus DNA using an immuno-dot-blot assay. DNA strand breakage by fine PM in A549 human lung epithelial cells was quantified using the alkaline comet assay. Both PM size distribution fractions elicited OH generation and 8-OHdG formations in calf thymus DNA. Significantly higher OH generation was observed for PM sampled at urban/industrial locations and for coarse PM. Samples of fine PM also caused DNA strand breakage in A549 cells and this damage could be prevented using the hydroxyl-radical scavengers 5,5-dimethyl-1-pyrroline-N-oxide and dimethyl sulfoxide. The observed DNA strand breakage appeared to correlate with the hydroxyl-radical-generating capacities of the PM samples but with different profiles for rural versus urban/industrial samples. In conclusion, when considered at equal mass, OH formation of PM shows considerable variability with regard to the sampling location and time and is correlated with its ability to cause DNA damage.

8-Hydroxy-2'-Deoxyguanosine↗

PubMed2003

Use of sol-gels as solid matrixes for simultaneous multielement determination by radio frequency glow discharge optical emission spectrometry: determinations of suspended particulate matter.

A new approach for the analysis of particulate matter by radio frequency glow discharge optical emission spectrometry (rf-GD-OES) is described. Dispersion of the particles in a sol-gel sample matrix provides a convenient means of generating a thin film suitable for sputter-sampling into the discharge. Acid-catalyzed sol-gel glasses synthesized from tetramethyl orthosilicate were prepared and spun-cast on glass substrates. The resultant thin films on glass substrates were analyzed to determine the discharge operating conditions and resultant sputtering characteristics while a number of optical emission lines of the film components were monitored. Slurries of powdered standard reference materials NIST SRM 1884a (Portland Cement) and NIST SRM 2690 (Coal Fly Ash) dispersed in the sols were cast into films in the same manner. Use of the sol-gels as sample matrixes allows for background subtraction through the use of analytical blanks and may facilitate the generation of calibration curves via readily synthesized, matrix-matched analytical standards in solids analysis. Detection limits were determined for minor elements via the RSDB method to be in the range of 1-10 microg/g in Portland Cement and Coal Fly Ash samples for the elements Al, Fe, Mg, S, and Si. Values for Ca were in the range of 15-35 microg/g. This preliminary study demonstrates the possibility of incorporating various insoluble species, including ceramics and geological specimens in powder form, into a solid matrix for further analysis by either rf-GD-OES or MS.

Journal Article↗