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PubMed2005

Induction of proinflammatory cytokines and C-reactive protein in human macrophage cell line U937 exposed to air pollution particulates.

Exposure to particulate matter air pollution causes inflammatory responses and is associated with the progression of atherosclerosis and increased cardiovascular mortality. Macrophages play a key role in atherogenesis by releasing proinflammatory cytokines and forming foam cells in subendothelial lesions. The present study quantified the inflammatory response in a human macrophage cell line (U937) after exposure to an ambient particulate sample from urban dust (UDP) and a diesel exhaust particulate (DEP). The effect of native UDP and DEP was compared with their corresponding organic extracts (OE-UDP/OE-DEP) and stripped particles (sUDP/sDEP) to clarify their respective roles. Exposure to OE-UDP, OE-DEP, UDP, DEP, and 2,3,7,8-tetrachlorodibenzo-p-dioxin led to a greater increase of interleukin (IL)-8, tumor necrosis factor-alpha, and cyclooxygenase-2 mRNA expression than did the stripped particles, whereas sUDP, sDEP, UDP, and DEP led to a greater production of C-reactive protein and IL-6 mRNA. The particles and the organic extract-induced expression of cyclooxygenase-2 and cytochrome P450 (CYP)1a1 was significantly suppressed by co-treatment with an aryl hydrocarbon receptor (AhR) antagonist, indicating that these effects are mainly mediated by the organic components, which can activate the AhR and CYP1a1. In contrast, the induction of C-reactive protein and IL-6 seems to be a particle-related effect that is AhR independent. The inflammatory response induced by particulate matter was associated with a subsequent increase of cholesterol accumulation, a hallmark of foam cells. Together, these data illustrate the interaction between particulate matter and the inflammatory response as well as the formation of cholesterol-accumulating foam cells, which are early markers of cardiovascular disease.

Air Pollutants↗

PubMedDate not supplied

Personal exposure to fine particles in children correlates closely with ambient fine particles.

To investigate the validity of ambient fine-particle concentrations as a measure of exposure in epidemiological time-series studies, we established the association between personal and ambient concentrations, within subjects, over time. We conducted repeated measurements of personal and ambient fine-particle concentrations in 13 children who lived in Wageningen, The Netherlands. For each child separately, we related personal exposures to ambient concentrations in a regression analysis. The median Pearson's correlation coefficient was 0.86. Personal fine-particle concentrations were also highly correlated with ambient particulate matter (i.e., < or = 10-microm) concentrations (median Pearson's correlation coefficient = .75). Personal fine-particle concentrations were typically approximately 11 microg/m3 higher than ambient concentrations. We excluded measurements of children who were exposed to environmental tobacco smoke, and the difference was only 5 microg/m3. The findings of high correlations between personal fine-particle concentrations and both ambient fine-particle concentrations and particulate matter (i.e., < or = 10-microm) found in this group of children provide support for investigators to use ambient particulate matter concentrations to measure exposure to fine-particle concentrations in epidemiological time-series studies.

Air Pollutants↗

PubMed1983

Rumen conditions that predispose cattle to pasture bloat.

Rumen contents from the dorsal sac were examined before alfalfa ingestion to determine factors that predispose cattle to pasture bloat. Chlorophyll concentration, buoyancy of particulate matter, and rates of gas production were significantly higher in cattle that subsequently bloated than in those that did not. Higher chlorophyll in bloat cases indicated accumulation of suspended chloroplast particles in the dorsal sac, perhaps due to increased buoyancy of the particulate matter. The higher fermentation rates (in the presence of glucose) suggested that the latent capacity for gas production was due to microbial colonization of suspended feed particles. Chlorophyll 4 h after feeding was also higher in bloated as compared to unbloated animals. In short, the microbial colonization and retention of particulate matter provided active inocula for promoting rapid legume digestion. Consequently, gas production was enhanced when feeding commenced, but the fermentation gases were trapped by the buoyant, frothy ingesta, resulting in the condition of pasture bloat.

Animals↗

PubMed1999

Exploring the clastogenic effects of air pollutants in São Paulo (Brazil) using the Tradescantia micronuclei assay.

This study was designed to determine the clastogenicity of particulate matter (aerodynamic diameter smaller than 10 microm) in the urban polluted air in the city of São Paulo. The Tradescantia-micronucleus (Trad-MCN) assay was used throughout this study to evaluate the clastogenicity of the extracts of the particulate matter. Tradescantia pallida (Rose) Hunt. cv. purpurea, an indigenous cultivar, was used in the Trad-MCN assay. The efficacy of this plant material for the Trad-MCN assay was validated with dose-response studies using formaldehyde and beta radiation. Dose-response curves were established with these known mutagens. The extracts of the PM10 particles at concentrations between 5 and 50 ppm induced a dose-related increase in MCN frequencies. The results indicate that T. pallida is equally sensitive to mutagens as the standard Tradescantia clone 4430 or 03 and the particulate matter in the urban air are clastogenic to the chromosomes of this plant. Inhalation of these particles by urban dwellers may affect their health by inducing similar genetic damage.

Air Pollutants↗

PubMed1998

Childhood asthma along the United States/Mexico border: hospitalizations and air quality in two California counties.

Since the passage of the North American Free Trade Agreement in 1993, there has been an increasing need to monitor environmental health trends that may be related to the rapid industrialization of the United States/Mexico border. We studied two counties on the California/Baja California border to obtain baseline data on trends in childhood asthma hospitalizations and two pollutants that aggravate asthma, ozone and particulate matter (less than 10 microns in diameter), from 1983 to 1994. Hospital discharge records of children 14 years and younger were analyzed, and rates by county, race, and sex were age-adjusted to the 1990 California population. Data on five ozone and particulate matter indices obtained from the California Environmental Protection Agency were used. Imperial County had the highest childhood asthma hospitalization rates in California for non-Hispanic whites and African-Americans, and the second highest for Hispanics. San Diego County had rates below the state average. Over the time period examined, rates in Imperial County increased 59%, while those in San Diego County decreased 9%. Maximum ozone levels increased 64% in Imperial County but decreased 46% in San Diego County. Particulate matter levels were four times higher in Imperial than in San Diego County. High rates of childhood asthma hospitalizations in Imperial County may be partially related to high levels of poverty and worsening air quality conditions produced by increased burdens on the local airshed. Asthma prevalence surveys and binational time-series analyses examining asthma-pollutant relationships are needed.

Adolescent↗

PubMed2005

Temporal variations and spatial distribution of ambient PM2.2 and PM10 concentrations in Dhaka, Bangladesh.

Concentrations and characteristics of airborne particulate matter (PM(10), PM(2.2) and BC) on air quality have been studied at two air quality-monitoring stations in Dhaka, the capital of Bangladesh. One site is at the Farm Gate area, a hot spot with very high pollutant concentrations because of its proximity to major roadways. The other site is at a semi-residential area located at the Atomic Energy Centre, Dhaka Campus, (AECD) with relatively less traffic. The samples were collected using a 'Gent' stacked filter unit in two fractions of 0-2.2 mum and 2.2-10 mum sizes. Samples of fine (PM(2.2)) and coarse (PM(2.2-10)) airborne particulate matter fractions collected from 2000 to 2003 were studied. It has been observed that fine particulate matter has a decreasing trend, from prior year measurements, because of Government policy interventions like phase-wise plans to take two-stroke three-wheelers off the roads in Dhaka and finally banned from January 1, 2003. Other policy interventions were banning of old buses and trucks to ply on Dhaka city promotion of the using compressed natural gas (CNG), introducing air pollution control devices in vehicles, etc. It was found that both local (mostly from vehicular emissions) and possibly some regional emission sources are responsible for high PM(2.2) and BC concentrations in Dhaka. PM(2.2), PM(2.2-10) and black carbon concentration levels depend on the season, wind direction and wind speed. Transport related emissions are the major source of BC and long-range transportation from fossil fuel related sources and biomass burning could be another substantial source of BC.

Air Pollutants↗

PubMed2001

Emissions of size-segregated aerosols from on-road vehicles in the Caldecott tunnel.

Particulate matter emissions from the California in-use vehicle fleet were measured as 37,500 vehicles traveled through two bores of the Caldecott Tunnel located in the San Francisco Bay area. Microorifice cascade impactors and filter-based samplers were used to determine the particle chemical composition as a function of particle size. Ammonia emissions from the vehicle fleet were measured as well. Concentrations of aerosol mass, organic carbon, elemental carbon, sulfate ion, nitrate ion, and ammonium ion, as well as 13 elements are reported. The particle mass distribution peaks in the particle size range 0.1-0.18 microm aerodynamic diameter (Da). Elemental carbon and organic matter were the largest components of particle mass in all the size ranges studied. The Caldecott Tunnel bores studied include one which carries light-duty vehicle traffic and one which carries a mixture of light- and heavy-duty vehicle traffic. From experiments conducted in both bores, estimates are made of the size distribution and chemical composition of particulate matter emissions extrapolated to the 100% light-duty and 100% heavy-duty vehicle fleets. The heavy-duty vehicle fleet emitted 1285 +/- 237 mg of fine particulate matter (Da < 1.9 microm)/kg of C contained in the fuel burned (corresponding to approximately 430 +/- 79 mg/km driven). Light-duty vehicles emitted less than 85 +/- 6 mg/kg of C in the fuel burned (corresponding to less than approximately 5.5 +/- 0.4 mg/km driven). Emissions of gas-phase ammonia in the Caldecott Tunnel were measured to be 194 and 267 mg/L of gasoline-equivalent fuel burned in the tunnel. The ammonia emissions are attributed to automobiles that were equipped with 3-way catalysts and operating fuel rich.

Aerosols↗

PubMed2004

An analysis of the association between respiratory symptoms in subjects with asthma and daily air pollution in Spokane, Washington.

The association between respiratory symptoms and ambient levels of particulate matter (PM) air pollution has been the focus of several panel studies. The majority of studies focused only on PM10, were conducted for relatively short periods, reported peak flow data, and involved children with asthma. The goal of our study was to evaluate the effect of particulate matter of various size fractions (PM10, PM2.5, PM1.0, and PM coarse fraction) on respiratory symptoms in both adults and children with asthma monitored over many months. Daily diary data on respiratory symptoms and medication use were collected. Air pollution data were collected by the local air agency and Washington State University. Data were collected in Spokane, WA, a semiarid city with diverse sources of particulate matter, including motor vehicles, woodstoves, agricultural burning, resuspended road dust, and dust storms. Sixteen adults and nine children living in Spokane participated in the study. The majority of adult subjects participated for over 1 yr and the children were studied for over 8 mo. In the children, we found a strong association between cough and PM10, PM2.5, PM coarse fraction, and PM1.0(p < .05). Sputum production and runny nose were associated with PM10and coarse fraction. However, no association was found between the presence of any respiratory symptom any PM metric in the adult subjects. These positive associations between various metrics of PM and respiratory symptoms in children suggest that children are more sensitive than adults to the effects of increased levels of PM air pollution or that the central site monitor was more representative for children who spend more time outdoors than adults. These findings also suggest that both larger and smaller particles can aggravate asthma symptoms.

Adolescent↗

PubMedDate not supplied

Application of a semi-automated SOS chromotest for measuring genotoxicities of complex environmental mixtures containing polycyclic aromatic hydrocarbons.

Soxhlet-extracted samples of standard reference materials (SRMs) 1649 (PAR1: urban dust/organics) and 1650 (PAR2: diesel particulate matter) from the U.S. Institute of Standards and Technology were tested for induction of SOS functions using a semi-automated version of the SOS chromotest with Escherichia coli PQ37. Concentrations of 10 polycyclic aromatic hydrocarbons in the extracts were determined using reversed-phase HPLC. Only the diesel particulate matter (PAR2) extracts expressed SOS induction activity, which decreased when metabolic activation was used. Mutagenic PAH compounds (e.g., chrysene) were found in higher concentrations in the PAR2 extracts than in the PAR1 extracts but this could not explain the genotoxicity while it was mainly exhibited without metabolic activation. The direct genotoxic activity of the diesel particulate matter sample PAR2 is probably caused by nitroaromatic compounds; this was also supported by parallel studies with the Ames/Salmonella assay.

Air Pollutants↗

PubMed1997

Unusual AMP-deaminase solubilization from teleost fish white muscle.

A previous study described an unusual influence of neutral salts on the behavior of trout muscle AMP-deaminase (AMPD) in its interactions with subcellular particulate matter (Lushchak and Storey 1994, Fish Physiol. Biochem. 13: 356-368). The present study shows that this behavior is also shared by the muscle enzyme of two other fish species, sea scorpion (Scorpaena porcus) and corb (Sciena umbra), indicating that this describes a principle for AMPD interaction with cellular particulate material. AMPD binding to particulate matter increased with increasing KCl concentration through the physiological range (100-200 mM), but at higher salt concentrations the amount of bound enzyme was reduced. The pattern of binding was not influenced by hydrophobic interactions since addition of the nonionic detergents, Triton X-100 or Tween-80, did not alter the distribution of bound versus free enzyme although both detergents, at low concentrations, enhanced enzyme maximal activity. AMPD binding to particulate matter was also influenced by pH, the amount of free enzyme rising by nearly 3-fold as pH fell within the physiological range from 7.5 to 6.5. It is concluded that neither electrostatic nor hydrophobic forces alone can account for the unusual solubilization of AMPD from fish muscle and it is possible that the effect is also related to ion-induced conformational changes in the structure of AMPD and/or of the myosin to which the enzyme binds.

AMP Deaminase↗

PubMed2000

The contributions of emissions and spatial microenvironments to exposure to indoor air pollution from biomass combustion in Kenya.

Acute and chronic respiratory diseases, which are causally linked to exposure to indoor air pollution in developing countries, are the leading cause of global morbidity and mortality. Efforts to develop effective intervention strategies and detailed quantification of the exposure-response relationship for indoor particulate matter require accurate estimates of exposure. We used continuous monitoring of indoor air pollution and individual time-activity budget data to construct detailed profiles of exposure for 345 individuals in 55 households in rural Kenya. Data for analysis were from two hundred ten 14-hour days of continuous real-time monitoring of concentrations of particulate matter [less than/equal to] 10 microm in aerodynamic diameter and the location and activities of household members. These data were supplemented by data on the spatial dispersion of pollution and from interviews. Young and adult women had not only the highest absolute exposure to particulate matter (2, 795 and 4,898 microg/m(3) average daily exposure concentrations, respectively) but also the largest exposure relative to that of males in the same age group (2.5 and 4.8 times, respectively). Exposure during brief high-intensity emission episodes accounts for 31-61% of the total exposure of household members who take part in cooking and 0-11% for those who do not. Simple models that neglect the spatial distribution of pollution within the home, intense emission episodes, and activity patterns underestimate exposure by 3-71% for different demographic subgroups, resulting in inaccurate and biased estimations. Health and intervention impact studies should therefore consider in detail the critical role of exposure patterns, including the short periods of intense emission, to avoid spurious assessments of risks and benefits.

Adolescent↗

PubMed1975

Particulate contamination and stability of three additives in 0.9% sodium chloride injection in plastic and glass large-volume containers.

The effect of particulate matter and stability of three parenteral drugs upon addition to glass and flexible polyvinyl chloride containers of 0.9% sodium chloride injection was studied. Aminophylline, lidocaine hydrochloric and metaraminol bitartrate were added to the solution in therapeutic quantities using techniques normally practiced by the hospital pharmacist. Statistical comparisons of the amount of particulate matter present were made for each solution consisting of drug added to plastic and glass bottles, drug filtered through a 0.22-mum filter and then added to the solution in plastic bags, controls for bags and bottles, and solutions with adjusted pH values to simulate the pH attained after addition of the drug to the solution. A correlation appeared to exist between the quantity of particulate matter and the amount of unfiltered drug solution added to the large-volume parenteral containers. Differences in storage and handling had an influence on the initial quantity of particles found in the plastic bags, no significant change in concentration of the drugs occurred during the 24-hour test period.

Aminophylline↗

PubMed1997

Comparison of the mutagenicity of chemical agents released during coke production.

Benzene- and acetone-extracted samples of airborne particulate matter collected in two coke plants were analysed for their content of genotoxic agents (coal tar pitch volatiles (CTPVs), polycyclic aromatic hydrocarbons (PAHs): benzo/a/pyrene, pyrene, dibenzo/a,h/anthracene, anthracene and fluoranthene) following the identification and quantification of the compounds as well as the evaluation of their mutagenic activity using in vitro reverse mutation assay. Results of determinations at the top section of coke batteries were compared. Mean concentrations of total dust, CTPVs and B/a/P were as follows: 2.06 mg/m3, 0.63 micrograms/m3 in plant A, and 2.77 mg/m3, 0.89 mg/m3 and 0.35 micrograms/m3 in plant B, respectively. All the extracts of particulate matter samples increased the induction of bacterial mutation in both +S9 and -S9 tests. The exposures to mutagenic airborne particulate matter were in the range of 98-683 rev./m3 (-S9): 714-2214 rev./m3 (+S9) in plant A, and 21-496 rev./m3 (-S9); 68-850 rev./m3 (+S9) in plant B. The correlation between mutagenic potential and concentrations of tested agents was insignificant. The coke oven emission seemed to be higher in plant A with side charging of coal.

Extraction and Processing Industry↗

PubMed1983

[Measurements of iron, lead, arsenic and selenium concentration in respirable and nonrespirable fractions of Berlin urban aerosols].

In the scope of air quality determinations in the city of Berlin, size fractioned immission concentrations of the heavy metals iron, lead and cadmium and the metalloids arsenic and selenium in suspended particulate matter in air were determined at a highly polluted urban site. The samples were gathered from Juli until December 1981 with a 6-stage-plus-backup high-volume cascade impactor, extracted with 33% HNO3 and analyzed with atomic absorption photometry (AAS) (flame: iron and lead, hydride system: arsenic and selenium) and inductively coupled plasm spectroscopy (ICP) (cadmium). The results show, that - the applied sampling and analyzing procedure proved to be suitable, - the immission concentrations of suspended particulate matter less than 10 micron in Berlin are comparatively high, with values up to 295 ng/m3, - the immission concentrations of the selected trace elements in suspended particulate matter less than 10 micron in Berlin are comparatively low for an industrialized area like this city (Fe: 1280 ng/m3, Pb: 325 ng/m3, Cd: 3.74 ng/m3, As: 11.9 ng/m3, Se: 1.6 ng/m3), but increase markedly during periods of air stagnation as they are quite common in the Berlin winter season (Fe: 2970 ng/m3, Pb: 859 ng/m3, Cd: 8.26 ng/m3, As: 67.3 ng/m3, Se: 6.68 ng/m3), - lead, cadmium, arsenic and selenium of main environmental hygienic interest were concentrated on particles smaller than 2 micron.

Air Pollutants↗

PubMed1988

The asiatic clam, Corbicula fluminea: An indicator of trace metal pollution in the Shatt al-Arab River, Iraq.

The potential of Corbicula fluminea (Müller) as an indicator for trace metal pollution was investigated. Laboratory experiments show that Corbicula has the capability to accumulate and eliminate trace metals in relation to their concentrations in ambient water. However, an effect of individual size was observed. Seasonal variations in the concentrations of Cd, Co, Cu, Fe, Mn, Ni, Pb, V and Zn in Corbicula, water and particulate matter from the upper section of the Shatt al-Arab River were studied. Sediment samples were also analysed. Metal concentrations were determined by means of flameless AAS. It was found that Corbicula is a suitable bio-indicator for monitoring of trace metal pollution. Metal concentrations in Corbicula tissues correlated better with their corresponding concentrations in particulate matter than with the dissolved form. Temporal variations in metal concentrations were attributed to several factors, including fluctuations in metal inputs, and in geochemical and hydrological characteristics of the water. The obtained levels of trace metals were comparable to those reported for control sites, with the exception of Cd, Cu and Zn whose concentrations were higher in both Corbicula and particulate matter.

Journal Article↗

PubMed1984

Phagocytosis in the spleen of the sunfish Lepomis spp.

A histological investigation of the filtering function of the spleen of the sunfish Lepomis spp. was conducted by light, scanning, and transmission electron microscopy. The parenchyma of the organ is predominantly red pulp, a system of splenic cords and sinuses. The white pulp consists of loose lymphoid tissue which forms a cuff around the pulp arteries. Filtering of particulate matter from the blood occurs in the red pulp by phagocytes of the pulp cords and ellipsoids (periarterial macrophage sheaths). The ellipsoids are pale-staining cuffs of macrophages and reticular cells in a framework of reticular fibres surrounding the arterial capillaries. Destruction of effete blood cells (especially erythrocytes) is confined to the pigment nodules; particulate matter is not taken up by the nodules. These yellow-brown bodies are dispersed throughout the red pulp and are bounded by a reticular capsule. They contain masses of phagocytes and have the appearance of a morula. They are associated with blood vessels and are surrounded by sinusoids. Prussian Blue stain shows the presence of haemosiderin within their phagocytes. The phagocytes of the pigment nodules are filled with inclusions such as residual bodies, siderosomes, and fragments of erythrocytes. The early filtering of particulate matter by the phagocytes of the pulp cords and ellipsoids may allow for a more efficient phagocytosis of erythrocytes by the pigment nodules, followed by storage and reutilization of iron-containing compounds uncontaminated by other phagocytosed material.

Animals↗

PubMed2004

Airborne environmental pollutant concentration and hospital epistaxis presentation: a 5-year review.

To investigate the hypothesized relationship between various daily atmospheric pollutant concentrations and hospital epistaxis presentation. A retrospective analysis of all presentations of non-traumatic epistaxis to our institution was performed, and the results were cross-referenced with London air quality data supplied by the National Air Quality Data Archive at the National Environmental Technology Centre (NETCEN) at the multi-centre tertiary referral ENT Department. An analysis of epistaxis presentation to St George's Hospital during the 5-year period January 1997-2002 was made from the patient administration system and accident and emergency records. The study includes 1373 emergency patients after traumatic and iatrogenic epistaxis were excluded. Factors measured were atmospheric ozone (O(3)), carbon monoxide (CO), sulphur dioxide (SO(2)), nitrogen dioxide (NO(2)) and particulate matter less than 10 mum in diameter (PM(10)). Hospital epistaxis presentation and atmospheric pollutant concentration were documented for each day of the 5-year period, weekly change in both parameters was recorded and statistical analysis was performed. The statistical methods used are linear correlation using Pearson's coefficient. Increased hospital epistaxis presentation was strongly associated with increased concentration of airborne particulate matter (r = 0.289, P < 0.001; significant if P < 0.05) and less strongly associated with increased concentrations of atmospheric O(3) (r = 0.150, P = 0.019; significant if P < 0.05). There was no association between epistaxis attendance and atmospheric concentrations of CO, NO(2) and SO(2) in this study. The concentrations of local airborne particulate matter and atmospheric O(3) in the days preceding hospital attendance for epistaxis are relevant when considering the associations of the episode. This further increases understanding of the pathophysiology of spontaneous epistaxis.

Air↗

PubMed1998

Utility of insufflation filters in laparoscopic surgery.

OBJECTIVES: To determine whether filters, regularly used as part of the insufflator tubing during laparoscopic surgery, trap microbial and particulate matter from CO2 tanks, thus preventing passage from one patient to another. METHODS: A total of 67 used filters were collected from 17 CO2 tanks and six insufflation machines at three local hospitals, and sterile unused filters were used as controls. The used filters were distributed equally and sequentially into three groups: Group I-viewed under a dissecting microscope for particulate matter; group II-examined by mass spectrometry for contamination with oils and other impurities; group III-incubated on sheep blood agar plates and evaluated for growth of microorganisms. RESULTS: Negative. Used filters were indistinguishable by all parameters from controls. CONCLUSIONS: This limited study suggests filters now used in laparoscopic surgery fail to trap microbes or particulate matter. The question remains whether tank waste is absent or these filters fail to trap waste matter.

Bacteria↗