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PubMed2005

A correlation of secondary aerosol (nitrate and sulfate) with respirable particulate matter (RPM) in ambient air at different traffic junctions of Vadodara city.

The correlation study of secondary aerosol (nitrate and sulfate) with RPM in ambient air at different traffic junctions of Vadodara city is reported. RPM was analyzed using Ion Chromatography technique and measured the level of nitrate and sulfate in ambient air. The correlation studies of these particulates with RPM have been established. The average concentration of sulfate and nitrate in ambient air was found 35.74 microg/m3 and 24.22 microg/m3, which ranged of 5.33-84.69 and 1.93-77.86 microg/m3 respectively. The correlation of RPM and SO4 (r = 0.813, P<0.01), RPM-NO3 (r = 0.5549, P<0.01) and SO4-NO3 (r = 0.6133, P<0.01) were found significant. The presence of sulfate and nitrate in RPM is 8.25% and 5.60% . The pH of water extract of RPM averaged 6.81, which ranged 6.17-7.28. Regression analysis result showed that the relationship between RPM-SO4 was significantly (R2=0.66215) correlated. This indicate that probably the secondary aerosols such as nitrate and sulfate in excess may cause irritation and increasing lung disease.

Aerosols↗
PubMedDate not supplied

Childhood respiratory symptoms, hospital admissions, and long-term exposure to airborne particulate matter.

The effects of long-term exposure to air pollution on respiratory symptoms and respiratory hospitalization (for asthma, bronchitis or pneumonia) were assessed in a cross-sectional study of children (ages 7--11 years, N=667) living in a moderately industrialized city in Central Slovakia. Individual health, residence and family history data obtained through the CESAR study were coupled, using Geographic Information System (GIS) technologies, with total suspended particulate (TSP) exposure estimates derived from dispersion modeling of almost all local stationary sources. These data were used to assess, at the intra-city level and child-specific level, the potential for TSP as a risk factor for respiratory disease in children. TSP, PM10, and PM2.5 monitored ambient concentrations are highly correlated in the study location. Modeled TSP concentrations resulting from local source emissions are dominated by a large wood processing facility, suggesting variation in exposures among children. The prevalence of respiratory non-asthmatic symptoms and hospitalizations was associated with increased TSP. No association between long-term exposure to TSP and asthma diagnosis or wheeze symptoms was found. Logistic regression modeling indicated a significant increase in hospital admissions for asthma, bronchitis or pneumonia associated with increasing air pollution (OR 2.16, CI, 1.01--4.60), doctor-diagnosed bronchitis (OR 1.53, CI, 1.02-2.30), and parent-reported chronic phlegm (OR 3.43, CI, 1.64--7.16), expressed as odds for a 15 microg/m3 increase in estimated TSP exposure, and these increases are not due to differences in socio-economic, health care or other identified factors.

Air Pollution↗
PubMedDate not supplied

Evaluation of the influence of open and closed-ampoule technologies on particulate matter in small-volume parenterals.

SVP in glass ampoules are manufactured using two main different technological production processes: the open-ampoule process (O) and the closed-ampoule process (C). In principle, the open-ampoule production technology should lead to better controlled production process. To test this hypothesis and quantify the possible qualitative differences in the manufactured ampoules, a suitable experimental design was set up. The two ampoule production processes have been compared on the basis of the visible particulate burden. Two batches of ampoules filled with water for injections were produced for each type of process, following conventional industrial procedures. Two samples of 20,000 units were taken from each batch and inspected with different automatic inspection systems: two Brevetti CEA machines (S1, S2--light scattering) and two EISAI machines (S3, S4--light absorbtion). The comparison between the processes was based on the rejection percentage. On both inspection machines the open-ampoule production samples present rejection percentages (ranging from 0.154% to 1.248% rejection percentages) which, on average, are lower than those detected in closed-ampoule production (ranging from 1.434% to 3.86% rejection percentages). The difference between the two processes is even more marked if we also consider the data obtained using inspection machines S3 and S4. The substantial differences in performance of the four inspection machines stress the need to provide for adequate validation procedures.

Drug Contamination↗
PubMed2001

Sampling and Raman confocal microspectroscopic analysis of airborne particulate matter using poly(dimethylsiloxane) solid-phase microextraction fibers.

Commercial poly(dimethylsiloxane) (PDMS) 7-microm solid-phase microextraction (SPME) fibers were used for sampling and Raman spectroscopic analysis of a tailpipe diesel exhaust, candle smoke, cigarette smoke, and asbestos dust. Samples were collected via direct exposure of the SPME fiber to contaminated air. The mass loading for SPME fibers was varied by changing the sampling time. Results indicate that PDMS-coated fibers provide a simple, fast, reusable, and cost-effective air sampling tool for airborne particulates. The PDMS coating was stable; Raman bands of the PDMS coating were observed exactly at the same wavenumber positions before and after air sampling. Raman spectroscopic analysis resulted in identification of several characteristic bands allowing chemical speciation of particulates. The advantage of the SPME fiber is the open bed geometry allowing for application of various spectroscopic methods of particulate analysis. This paper describes the first-ever combined application of SPME technology with Raman confocal microspectroscopy for sampling and analysis of airborne particulates. Advantages of the combination of solid-phase microextraction and Raman microspectroscopy for airborne particulate analysis are discussed. Challenges associated with combined SPME sampling and Raman analysis of single particles are also described.

Journal Article↗
PubMed1998

Air pollution by particulate matter in the industrialized city of Leoben, Austria.

At seven sites in Leoben, Austria, aerosol particles were sampled in two size fractions by a dichotomous sampler using virtual impaction: the fine fraction (alveolar aerosol) with an aerodynamic diameter dac < 2.5 microns (PM2.5), and the coarse fraction (tracheobronchial aerosol) with an dac between 2.5 and 10 microns. It is believed that these particles are able to reach the lower regions of the human respiratory tract, and thus be responsible for most of the adverse health effects associated with suspended particulate pollution. A second sampling procedure was made collecting the PM2.5 fraction and after leaching with nitric acid, lead, zinc, cadmium, copper, chromium and vanadium were determined with an inductively coupled plasma mass spectrometer (ICP-MS). For one sample point a third sampling was carried out and both fractions were subsequently leached with water and dilute hydrochloric acid. Pb, Zn, Mn, Fe, Cd, Ni, Cu, Rb, Sr, Mo, Cs, Ba and Tl were determined by ICP-MS.

Air Pollution↗
PubMed2002

Monitoring urban air particulate matter (fractions PM 2.5 and PM 10) genotoxicity by plant systems and human cells in vitro: a comparative analysis.

Increased incidence of mortality and sickness due to cardiopulmonary complications has been associated with elevated levels of urban air particles (UAP), with an aerodynamic diameter of 10 microm (PM 10) and 2.5 microm (PM 2.5). In the present report alternative plant systems and human cells in vitro are associated with human hazard and genotoxic risk assessment of UAP. The genotoxic activities associated with the coarse (PM 10) and the fine fraction (PM 2.5) of airborne particulates have been analyzed by evaluating micronuclei induction and/or sister-chromatid exchange (SCE) using in vitro models of Daucus carota and HS 27 human fibroblast cell suspensions and Zea mays root meristems. Results show variability in the response of the test systems and indicate that the mutagenicity trend in both plant and human cell cultures was directly correlated to the concentration of carbon-rich particles in the fraction of the PM 2.5 airborne particulates. Moreover, in plant tissues, the frequency of micronuclei and SCE was related to an enhancement of the specific activity of the stress-related enzyme peroxidase.

Air Pollutants↗
PubMed2001

Back-trajectory analyses of fine particulate matter measured at Big Bend National Park in the historical database and the 1996 scoping study.

Analyses of the sources of fine particles associated with visibility reduction at Big Bend National Park during a 10-year period from 1989-1998 and from a regional visibility scoping study conducted during September and October 1996 at 19 sites in Texas and Mexico are summarized and compared. Fine sulfate particles are the largest fraction of the fine mass, and scattering by sulfates is estimated to be nearly half of the non-Rayleigh light extinction at Big Bend. Fine particulate sulfur concentrations are seasonal, with the highest values occurring during the summer and fall when back trajectory analyses show that air masses are most likely to arrive at Big Bend from the southeast after passing over Mexico or from areas to the northeast including east Texas. Episodically, high concentrations of fine mass and high light extinction values can be due to other species such as fine organic carbon or blowing soil dust. Organic carbon concentrations are often extremely high during the spring, especially during May. A combination of back trajectory analyses and the coincidence of high organic carbon and high non-soil potassium concentrations leads to the hypothesis that these concentrations are due to fires, primarily seasonal agricultural burning in Mexico and Central America. Fine soil concentrations often reach values that are twice the annual mean during July. These concentrations also frequently have high Al/Ca ratios, indicative of Saharan dust. Back trajectories associated with these events show air masses arriving from the southeast and are consistent with the hypothesis of transport of air masses from Africa during July. There is a high frequency of transport of air masses from Mexico to Big Bend, especially during the summer when fine mass concentrations and light extinction are highest. Therefore, sources and potential sources of sulfates and other fine particles in Mexico, particularly in areas southeast of the park have a high likelihood of contributing to visibility degradation at the park. Source areas to the northeast of the park, in east Texas and farther upwind also contribute to high fine sulfate concentrations.

Air Movements↗
PubMed2002

Using sulfur as a tracer of outdoor fine particulate matter.

Six homes in the metropolitan Boston area were sampled between 6 and 12 consecutive days for indoor and outdoor particle volume and mass concentrations, particle elemental concentrations, and air exchange rates (AERs). Indoor/outdoor (I/O) ratios of nighttime (i.e., particle nonindoor source periods) sulfur, PM2.5 and the specific particle size intervals were used to provide estimates of the effective penetration efficiency. Mixed models and graphical displays were used to assess the ability of the I/O ratios for sulfur to estimate corresponding I/O ratios for PM2.5 and the various particle sizes. Results from this analysis showed that particulate sulfur compounds were primarily of outdoor origin and behaved in a manner that was representative of total PM2.5 in Boston, MA. These findings support the conclusion that sulfur can be used as a suitable tracer of outdoor PM2.5 for the homes sampled in this study. Sulfur was more representative of particles of similar size (0.06-0.5 microm), providing evidence that the size composition of total PM2.5 is an important characteristic affecting the robustness of sulfur-based estimation methods.

Air Pollution↗
PubMed1998

The conventionally ventilated operating theatre and air contamination control during cardiac surgery--bacteriological and particulate matter control garment options for low level contamination.

OBJECTIVE: The purpose of the study was to compare the usefulness of a conventional bacteriological technique with that of particle counting under lower air contamination and better aseptic conditions achieved with special staff garments and covering for the patient. Contamination levels were estimated with continuous on line air particle counting measurement, volumetric intermittent short period aerobic bacteriological cultures and wound surface contact cultures. METHODS: In a series of 66 consecutive coronary artery bypass operations performed by the same team and in the same theatre using different types of patient and staff clothing, the impact of a reduced bacteriological and particulate contamination were assessed. The volumetric air contamination of particles > or =5 microm and bacteria-carrying particles were monitored 30 cm above the sternal wound. The bacterial contamination and bacterial wound infections in the sternal and leg wounds were assessed as well. RESULTS: With the alternative garment and textile system, the air counts fell from 25 colony-forming units (CFU)/m3 to 7 CFU/m3 (P < 0.0038). The contamination of the sternal wound was reduced by 46% and that of the leg wound by >90%. In order to give continuous contamination feedback during the whole operation to the theatre staff, particle counts > or =5 microm were monitored and visualized. Air particle counts decreased rapidly from 850 particles/m3 and stabilized to approximately 50 particles/m3 when the alternative clothing system was used (P < 0.001). Low particle counts > or =5 microm should offer the possibility to indirectly estimate air bacteria carrying particle counts during the entire operation. Less than 20% of the total count in this size group carries bacteria. The low air contamination was achieved even in an ordinary ventilated theatre when individual team members used clean air suits in combination with impermeable patient drapes. When air particle level < or =50 particles/m3 is reached, the bacterial air contamination is in the order of that of orthopaedic hip operations. The staff must during the entire operation adjust their activity to air asepsis. CONCLUSIONS: The use of clean air suits and impermeable patient clothing results in a low exogenous contamination of air and wound. Continuous air particle monitoring is a good intraoperative method to monitor the air contamination longitudinally in an operating theatre.

Air Microbiology↗
PubMed2004

A comparison of asbestos and urban particulate matter in the in vitro modification of human alveolar macrophage antigen-presenting cell function.

The mechanism for how inhaled particles cause or exacerbate human diseases is not known. It is clear, however, that some particles are more bioactive than others. One possible mechanism may involve a modification of antigen-presenting cell function. In this study, 2 forms of asbestos (crocidolite and Libby amphibole) and PM(2.5) (an urban particle) were cultured with human alveolar macrophages (HAMs) to determine whether antigen-presenting cell (APC) function was altered. HAMs were exposed to the bioactive particles, asbestos and PM(2.5), for 24 hours, then isolated free of extracellular particulates and nonviable cells. Isolated HAMs were then cultured with autologous lymphocytes in an 11-day APC assay using tetanous toxoid as the antigen and the resulting culture supernatants were assayed for lymphocyte-derived cytokines. Asbestos exposure, regardless of type, up-regulated a TH1 lymphocyte-derived cytokine, interferon gamma (IFNgamma), and the TH2 lymphocyte-derived cytokines interleukin-4 (IL-4) and interleukin-13 (IL-13). PM(2.5) exposure up-regulated all 3 cytokines also. Although cytokine production levels were significantly higher for the treatment compared to control cultures as a group, there was extreme variability in the responses between subjects. In addition, there was no correlation between an individual's cells' response to asbestos verses PM, suggesting that more than one possible mechanism exists for a particle-induced APC effect and individual differential sensitivities to inhaled bioactive particles. This work supports the hypothesis that some inhaled particles can modify immune function by directly affecting APCs thus up-regulating the normal lymphocyte response to antigens in the lung.

Air Pollutants↗
PubMed2002

PCDD/Fs and PCBs in airborne particulate matter of the greater Thessaloniki area, N. Greece.

Particle-bound polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and polychlorinated biphenyls (PCBs) were monitored at two sites in northern Greece for an eight-month period in 1999. PCDD/F concentrations were close to the lower end of reported values worldwide. Excepting a few cases, the PCDD/Fs homologue profile was stable. The gaseous PCDD/F fractions calculated were found to account for a small percentage of the total concentrations (<2% for OCDD/Fs and HpCDD/Fs, while 30-35% for TCDFs). Particle-bound PCBs were also found at low concentrations which, however, were higher at the urban site. Calculations of the dry deposition of particulate PCDD/ Fs and PCBs gave mean values of 0.52 and 0.59 pg I-TEQ/m2/day of PCDD/Fs, while 242 and 74 pg/m2/day of sigmaPCBs for the urban and the semirural areas respectively. An anticorrelation of PCDD/F concentrations with ambient temperature was derived particularly for the lower chlorinated congeners. A weak association with winds of western and southern origin was also observed. Factor analysis and literature source profiles were employed to identify possible emission sources. It was appeared that the PCDD/F compositional pattern of TSP is influenced by mixed sources the most prominent being uncontrolled fires and car exhausts.

Air Movements↗
PubMed1980

S(IV) chemistry in smelter produced particulate matter.

Epidemiological and animals toxicological studies have indicated that reactions between SO2(g) and metal containing aerosols result in the formation of respiratory irritants. It had initially been suggested by EPA that sulfate per se was responsible for the observed health effects. That now appears unlikely. These studies point out the importance of understanding in detail the chemical species formed by such interactions. In the present paper procedures which have been used to study the formation of aerosol inorganic S(IV) species are described, together with the results obtained from studies in the flue line, workroom, and plume of smelters. Both atmospheric and laboratory studies indicate that very stable complexes of S(IV) with Fe(III) or Cu(?) can form in aerosols. The data suggest that the concentration of these (S(IV) complexes in primary particulate emissions from smelters will be about 10% of the sulfate concentration. In plumes the concentration of inorganic S(IV) varied from 10 to 80% of the sulfate concentration. The most important variable controlling the formation of these S(IV) complexes in a plume aerosol droplet is the aerosol acidity. The formation of aerosol inorganic S(IV) complexes in the plume is not related to the formation of sulfate. There have been no studies previously reported that would allow an unequivocal evaluation of the toxicological implications of the chemistry reviewed in this paper. If these various S(IV) species are responsible at the low concentrations reported here for the "synergistic" effects previously reported between SO2(g) and aerosols, then additional toxicological work would appear warranted.

Aerosols↗
PubMed2000

Daily mortality in the Philadelphia metropolitan area and size-classified particulate matter.

Time-series of daily mortality data from May 1992 to September 1995 for various portions of the seven-county Philadelphia, PA, metropolitan area were analyzed in relation to weather and a variety of ambient air quality parameters. The air quality data included measurements of size-classified PM, SO4(2-), and H+ that had been collected by the Harvard School of Public Health, as well as routine air pollution monitoring data. Because the various pollutants of interest were measured at different locations within the metropolitan area, it was necessary to test for spatial sensitivity by comparing results for different combinations of locations. Estimates are presented for single pollutants and for multiple-pollutant models, including gaseous pollutants and mutually exclusive components of PM (PM2.5 and coarse particles, SO4(2-) and non-SO4(2-) portions of total suspended particulate [TSP] and PM10), measured on the day of death and the previous day. We concluded that associations between air quality and mortality were not limited to data collected in the same part of the metropolitan area; that is, mortality for one part may be associated with air quality data from another, not necessarily neighboring, part. Significant associations were found for a wide variety of gaseous and particulate pollutants, especially for peak O3. Using joint regressions on peak O3 with various other pollutants, we found that the combined responses were insensitive to the specific other pollutant selected. We saw no systematic differences according to particle size or chemistry. In general, the associations between daily mortality and air pollution depended on the pollutant or the PM metric, the type of collection filter used, and the location of sampling. Although peak O3 seemed to exhibit the most consistent mortality responses, this finding should be confirmed by analyzing separate seasons and other time periods.

Adolescent↗
PubMed2000

Multi-element analysis by inductively coupled plasma optical emission spectrometry of airborne particulate matter collected with a low-pressure cascade impactor.

A method was developed for the elemental analysis of size segregated particles ranging from 0.03 to 10 microns. Sampling and analysis problems are discussed in this paper. Particles were collected with a Dekati low-pressure cascade impactor. PTFE filters coated with oleic acid were used as substrate. Particles were microwave digested in closed vessels. The optimum digestion mixture was composed of HNO3 (1 mL), HF (50 microL) and H2O (1 mL). The optimal power setting and digestion time were studied in order to achieve an efficient digestion. A ca. 35 min microwave digestion cycle at a 650 W maximum power allowed complete digestion of the samples. Special emphasis was placed on the pressure in the closed vessels to avoid sample losses. Solution samples were analysed by inductively coupled plasma optical emission spectrometry using an ultrasonic nebuliser for 18 elements (Al, Ba, Ca, Cd, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, Pb, S, Sr, Ti, V, Zn). This procedure was tested with NIST Standard Reference Material 1648 Urban Particulate. Recoveries for certified elements ranged from 95 to 105% except for Al (90%). The influence of cascade impactor materials was investigated with 44 field samples. Strong artefacts due to contamination were shown for analysis at environmental concentrations of Al, Cr, Mn and Ni.

Air Pollutants↗
PubMed2005

Application of a two-stage Syrian hamster embryo cell transformation assay to cigarette smoke particulate matter.

The induction of transformation in Syrian hamster embryo (SHE) cells is a multifactorial process, in comparison to endpoints induced in in vitro genotoxicity assays such as Ames, mouse lymphoma and cytogenetics [Y. Berwald, L. Sachs, In vitro cell transformation with chemical carcinogens, Nature (London) 200 (1963) 1182-1184]. Furthermore, a number of non-genotoxic carcinogens and promoters such as clofibrate and diethylhexylphthalate, have been positively identified in this assay, while giving false negative results in traditional genotoxicity assays [H. Yamasaki, J. Ashby, M. Bignami, W. Jongen, K. Linnainmaa, R.F. Newbold, G. Nguyen-Ba, S. Parodi, E. Rivedal, D. Schiffmann, J.W.I.M. Simons, P. Vasseur, Nongenotoxic carcinogens: development of detection methods based on mechanisms: a European project, Mutat. Res. 353 (1996) 47-63]. A high concordance between results obtained in this assay when compared with rodent carcinogenesis bioassays has also been noted [R.J. Isfort, G.A. Kerckaert, R.A. LeBoeuf, Comparison of the standard and reduced pH Syrian hamster embryo (SHE) in vitro cell transformation assays to predict the carcinogenic potential of chemicals, Mutat. Res. 356 (1996) 11-63]. Carcinogenesis is known to be a multistage process, with agents potentially acting at each stage. Specifically, mouse skin painting experiments established that tumour induction could be mechanistically divided into two distinct phases, termed initiation and promotion. Initiation, is defined as the stage at which a normal cell is converted to a latent tumour cell, followed by promotion where the latent tumour cell progresses to a tumour [W.F. Friedwald, P. Rous, The initiating and promoting elements in tumour production: analysis of the effects of tar, benzpyrene and methylcholanthrene on rabbit skin, J. Exp. Med. 80 (1944) 101-125]. A protocol for the pH 6.7 SHE transformation assay has been developed which allows separation of cell transformation process into two phases, potentially analogous to initiation and promotion in vivo. This allows chemicals found to be positive in the traditional SHE cell transformation assay to be further classified as initiators or promoters. Following validation with known initiators, benzo(a)pyrene and N-methyl-N'-nitro-N-nitrosoguanidine and promoters, 12-O-tetradecanoyl-phorbol-13-acetate and phenobarbitone, the two-stage model was applied to cigarette smoke particulates which was found to act both at the initiation and promotion stage of cell transformation.

Animals↗
PubMedDate not supplied

PM-10 and heavy metals in particulate matter of the province of Lecce (Apulia, Southern Italy).

This paper shows the results of a preliminary study of air monitoring in the province of Lecce (Apulia, Southern Italy). In particular, the attention has been focused on the determination of the PM-10 level and of the concentration of nine metals (Cd, Cr, Cu, Fe, Mn, Ni, Pb, V and Zn) present on the filters which were collected in two towns (Lecce and Campi Salentina) from 2002 until 2003. The metals have been chosen on the basis of their toxicity and of their possible use as chemical tracers. The results have proved that PM-10 values and metals concentrations did not show substantial difference between the two towns and that PM-10 level and lead concentration are below the limit established by Italian law in force. The experiments have demonstrated a high correlation between iron and manganese in both sampling sites; this could be attributed to pollution of metallurgical origin. Multivariate statistical analysis, carried out by HCA and PCA methods, has been used in order to differentiate samples in relation to sampling sites, sampling period and meteorological conditions.

Air Pollutants↗
PubMedDate not supplied

Optimization of supercritical fluid extraction by carbon dioxide with organic modifiers of polycyclic aromatic hydrocarbons from urban particulate matter.

The main advantages of using supercritical fluids for the extractions of organic pollutants from environmental matrix is that they are inexpensive, contaminant free, and less costly to dispose safely than organic solvents. In this work, a series of extraction experiments were carried out using CO2 as supercritical fluid on a certified sample of "Urban dust" (NIST S.R.M. 1649a) to optimize the analytical parameters with the aim of investigating the extraction limit of organic pollutant by using an almost "organic solvent-free" technique. The certified sample contains small concentrations of several organic pollutants, as PAH and PCB. The initial tests of extraction were carried out with only CO2 in supercritical phase, by maintaining the temperature at 50 degrees C and 80 degrees C and by making the pressure vary between 230 bar and 600 bar. The effect of three organic modifiers (methanol, n-hexane and toluene), added at 5% in volume, has been considered. The yield of recovery has been estimated for anthracene, fluoranthene, chrysene, benzo[a]pyrene, indeno[1,2,3-cd]pyrene by GC-MS according to the increasing molecular weight.

Air Pollutants↗