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PubMed2004

First assessment of the PM10 and PM2.5 particulate level in the ambient air of Belgrade city.

INTENTION, GOAL, SCOPE, BACKGROUND: As the strong negative health effect of exposure to the inhalable particulate matter PM10 in the urban environment has been confirmed, the study of the mass concentrations, physico-chemical characteristics, sources, as well as spatial and temporal variation of atmospheric aerosol particles becomes very important. OBJECTIVE: This work is a pilot study to assess the concentration level of ambient suspended particulate matter, with an aerodynamic diameter of less than 10 microm, in the Belgrade central urban area. Average daily concentrations of PM10 and PM2.5 have been measured at three representative points in the city between June 2002 and December 2002. The influence of meteorological parameters on PM10 and PM2.5 concentrations was analyzed, and possible pollution sources were identified. METHODS: Suspended particles were collected on Pure Teflon filters by using a Mini-Vol low-volume air sampler (Airmetrics Co., Inc.; 5 l min(-1) flow rate). Particle mass was determined gravimetrically after 48 h of conditioning in a desiccator, in a Class 100 clean room at the temperature T = 20 degrees C and at about 50% constant relative humidity (RH). RESULTS AND DISCUSSION: Analysis of the PM10 data indicated a marked difference between season without heating--(summer; mean value 56 microg m(-3)) and heating season--(winter; mean value 96 microg m3); 62% of samples exceeded the level of 50 microg m(-3). The impact of meteorological factors on PM concentrations was not immediately apparent, but there was a significant negative correlation with the wind speed. CONCLUSIONS: The PM10 and PM2.5 mass concentrations in the Belgrade urban area had high average values (77 microg m(-3) and 61 microg m(-3)) in comparison with other European cities. The main sources of particulate matter were traffic emission, road dust resuspension, and individual heating emissions. When the air masses are coming from the SW direction, the contribution from the Obrenovac power plants is evident. During days of exceptionally severe pollution, in both summer and winter periods, high production of secondary aerosols occurred, as can be seen from an increase in PM2.5 in respect to PM10 mass concentration. RECOMMENDATION AND OUTLOOK: The results obtained gave us the first impression of the concentration level of particulate matter, with an aerodynamic diameter of less than 10 microm, in the Belgrade ambient air. Due to measured high PM mass concentrations, it is obvious that it would be very difficult to meet the EU standards (EEC 1999) by 2010. It is necessary to continue with PM10 and PM2.5 sampling; and after comprehensive analysis which includes the results of chemical and physical characterization of particles, we will be able to recommend effective control measures in order to improve air quality in Belgrade.

Aerosols↗

PubMed2003

Chronic diesel exhaust exposures of rats demonstrate concentration and time-dependent effects on pulmonary inflammation.

Long-term, repeated exposure to particles in air pollution increases the risk for chronic respiratory diseases and cardiorespiratory mortality. The biological linkages remain poorly understood in chronic exposure to particle matter. To elucidate and verify these linkages, we investigated long-term exposure to diesel emission with respect to dose dependence and the effect of components without particles from diesel emission in rats. Wistar rats were exposed to filtered air (C group), diesel exhaust at low (L group), medium (M group), and high level (H group), or at a medium concentration diesel exhaust without particulate matter (MG group), for 16 h/day, 6 days/wk, for 6, 12, 18, or 24 mo. Anesthetized animals were sacrificed and bronchoalveolar lavage (BAL) fluid from the lung and blood from the right ventricle were collected. Various biomarkers of inflammation and components of mucus and surfactant were determined. Changes in total cell counts and cell differentiation, total protein, mucus and surfactant components, and prostaglandin E(2) in BAL fluid, but not biomarkers in plasma, showed statistical differences among the C, L, M, and H groups during the experimental period. The changes in these biomarkers in the H group were greater than those in the M group, whereas those in the L group showed no significant changes compared with those in the C group during the experimental period. The onset of significant changes in inflammatory cells and these biomarkers in BAL fluid for the M and H groups was at 6 to 12 mo of exposure. The maximum level was reached at 12 to 18 mo of exposure. Although BAL prostaglandin E(2) decreased significantly at 6 mo of exposure in the M and H groups, this trend was not observed in the C and L groups. Animals exposed to a medium level of diesel exhaust without particulate matter showed significantly less inflammatory cells and various biomarkers in BAL fluid than animals exposed to the same level of diesel exhaust with particulate matter during the experimental period. These findings suggest that biological response to inhaled particles is aggravated during chronic exposure to diesel exhaust dose-dependently. Inflammation and overproduction of mucus and surfactant components reached a plateau at 12 or 18 mo of exposure during a 24-mo experimental period. No adverse effect of particles (less than 1.0 mg particles/m(3) of diesel emission) was observed in these rats. However, our data suggest that particulate matter plays an important role during development of chronic lung injury induced by diesel emission exhaust.

Animals↗

PubMed1989

Effects of changes in frequency of reticular contractions on fluid and particulate passage rates in cattle.

Four ruminally cannulated Hereford steers (531 +/- 32 kg) without weights (control; C) or with 24-kg weights (W) in the rumen were used in a double crossover design experiment to determine the effects of changes in frequency of reticular contractions at maintenance feed intakes on passage rates of particulate matter and fluid from the rumen. Duration of reticular contractions, apparent digestibilities and heat and methane productions were also determined. Weights in the rumen had no effect (P = .07) on frequency of reticular contractions before feeding; however, frequencies of reticular contractions were higher in C than in W steers during feeding (P = .03) and after feeding (P = .05). Weights in the rumen increased the average duration of contractions before feeding (P = .04), during feeding (P = .01) and after feeding (P = .05) by 12, 15 and 15%, respectively. Fractional outflow rates of ruminal and whole gastrointestinal particulate matter were 38% and 49% lower (P = .001) in C than in W steers, respectively. Weights in the rumen reduced (P = .001) methane production (liters/d) by 29%. Methane production was inversely correlated with fractional outflow rate for ruminal particulate matter (r = -.53; P = .034). Heat productions for W and C steers were 12.3 and 12.6 Mcal/d, respectively. Weights in the rumen had no effect on apparent digestibility. Duration of reticular contractions, in contrast to frequency of contractions, was the important factor influencing passage rates of both ruminal fluid and particulate matter. Methane production was decreased when passage rates were increased.(ABSTRACT TRUNCATED AT 250 WORDS)

Animal Feed↗

PubMed2002

Dose-response assessment and effect of particles in guinea pigs exposed chronically to diesel exhaust: analysis of various biological markers in pulmonary alveolar lavage fluid and circulating blood.

To elucidate dose-response and other effects of diesel particles in guinea pigs chronically exposed to diesel exhaust, various biomarkers for chronic obstructive lung diseases were studied using bronchoalveolar lavage (BAL) fluid and blood specimens. Guinea pigs were exposed 16 h/day, 6 days/wk, for 6, 12, 18, or 24 mo to filtered air (control group, n = 8-10), a low level of diesel exhaust (L group: NO(2) = 0.22 +/- 0.03 ppm; SO(2) = 0.6 +/- 0.19 ppm; particles = 0.21 +/- 0.07 mg/m(3), n = 8-10), medium level of diesel exhaust (M group; NO(2) = 1.07 +/- 0.09 ppm; SO(2) = 2.83 +/- 0.73 ppm; particles = 1.14 +/- 0.26 mg/m(3), n = 8-10), and high level of diesel exhaust (H group: NO(2) = 2.88 +/- 0.29 ppm; SO(2) = 6.49 +/- 1.75 ppm; particles = 2.94 +/- 0.69 mg/m(3), n = 8-10), or at a medium concentration of diesel exhaust without particulate matters (MG group: NO(2) = 1.01 +/- 0.09 ppm;#10; SO(2) = 2.66 +/- 0.64 ppm; particles = 0.01 +/- 0.01 mg/m(3), n = 8-10). Anesthetized animals were sacrificed and BAL fluid from the lung and blood from right ventricle were collected. Various biomarkers of inflammation, components of mucus and surfactant, bronchoconstrictors were determined. Changes of leukotriene C4 in plasma, eosinophil counts, biomarkers of inflammation and cytotoxicity, and mucus and surfactant components in BAL fluid were statistically different among the C, L, M, and H groups after adjustment for the exposure period and group-by-exposure period with respect to their interactions in two-way analysis of variance (ANOVA). The levels of these biomarkers in the H group were higher than those of the M group, whereas those of the L group showed no significant changes compared with those of the C group during experimental period. Onset of significant changes of these biomarkers for the M group was at 18 mo of exposure, whereas that for the H group was at 12 mo of exposure, which resulted in changes in the levels of biomarkers in BAL fluid. Although numbers of eosinophils in BAL fluid increased significantly in the M and H groups at 12 mo, only leukotriene C4 increased at 18 and 24 mo in blood and at 24 mo in BAL fluid. Animals exposed to the medium level of diesel exhaust without particulate matter showed significantly less increase of these biomarkers as compared with animals exposed to the same level of diesel exhaust with particulate matters. These findings indicate that chronic exposure to diesel exhaust induced continuous inflammation, overproduction of mucus, and phospholipids in the lung. Animals exposed to the high dose of diesel exhaust showed a plateau of biological responses at 12 mo of exposure. Particulate matter in diesel exhaust appears to play an important role in development of lung injury by chronic emission exhaust exposure.

Administration, Inhalation↗

PubMed2000

Associations between mortality and air pollution in central Europe.

Increased mortality has been observed in association with elevated concentrations of air pollutants in European cities and in the United States. We reassessed the effects of particulate matter in Central Europe. Mortality and air pollution data were obtained for a highly polluted region of the Czech Republic and a rural region in Germany. Poisson regression analyses were conducted considering trend, season, meteorology, and influenza epidemics as confounders in both a parametric and a nonparametric approach. The Czech Republic had a 3.8% increase in mortality [95% confidence interval (CI), 0.8-6.9%] in association with 100 microg/m(3) total suspended particles (TSP) (lagged 2 days) for the time period 1982-1994. During the last 2 years of study, 68% of the TSP consisted of particulate matter [less than/equal to] 10 microm in aerodynamic diameter (PM(10)). An increase of 100 microg/m(3) TSP (lagged 1 day) was associated with a 9.5% increase in mortality (CI, 1.2-18.5%) and 100 microg/m(3) PM(10 )(lagged 1 day) showed a 9.8% increase in mortality (CI, 0.7-19.7%). We found no evidence for an association between mortality and particulate matter in the rural area in Germany at the Czech border. Data from the coal basin in the Czech Republic suggested an increase in mortality associated with the concentration of particulate matter in a highly polluted setting in Central Europe that is consistent with the associations observed in other western European cities and in the United States.

Adolescent↗

PubMed1998

Association of marine archaea with the digestive tracts of two marine fish species.

Recent studies have shown that archaea which were always thought to live under strict anoxic or extreme environmental conditions are also present in cold, oxygenated seawater, soils, the digestive tract of a holothurian deep-sea-deposit feeder, and a marine sponge. In this study, we show, by using PCR-mediated screening in other marine eukaryotes, that marine archaea are also present in the digestive tracts of flounder and grey mullet, two fish species common in the North Sea, in fecal samples of flounder, and in suspended particulate matter of the North Sea water column. No marine archaea could be detected in the digestive tracts of mussels or the fecal pellets of a copepod species. The archaeal 16S ribosomal DNA clone libraries of feces of flounder and the contents of the digestive tracts of grey mullet and flounder were dominated by group II marine archaea. The marine archaeal clones derived from flounder and grey mullet digestive tracts and feces formed a distinct cluster within the group II marine archaea, with 76.7 to 89. 8% similarity to previously described group II clones. Fingerprinting of the archaeal community of flounder digestive tract contents and feces by terminal restriction fragment length polymorphism of archaeal 16S rRNA genes after restriction with HhaI showed a dominant fragment at 249 bp, which is likely to be derived from group II marine archaea. Clones of marine archaea that were closely related to the fish-associated marine archaea clones were obtained from suspended particulate matter of the water column at two stations in the North Sea. Terminal restriction fragment length polymorphism fingerprinting of the archaeal community present in suspended particulate matter showed the same fragment pattern as was found for the archaeal community of the flounder digestive tract contents and feces. These data demonstrate that marine archaea are present in the digestive tracts and feces of very common marine fish. It is possible that the marine archaea associated with the digestive tracts of marine fish are liberated into the water column through the feces and subsequently contribute to the marine archaeal community of suspended particulate matter.

Animals↗

PubMed1998

Acute effects of inhaled urban particles and ozone: lung morphology, macrophage activity, and plasma endothelin-1.

We studied acute responses of rat lungs to inhalation of urban particulate matter and ozone. Exposure to particles (40 mg/m3 for 4 hours; mass median aerodynamic diameter, 4 to 5 microm; Ottawa urban dust, EHC-93), followed by 20 hours in clean air, did not result in acute lung injury. Nevertheless, inhalation of particles resulted in decreased production of nitric oxide (nitrite) and elevated secretion of macrophage inflammatory protein-2 from lung lavage cells. Inhalation of ozone (0.8 parts per million for 4 hours) resulted in increased neutrophils and protein in lung lavage fluid. Ozone alone also decreased phagocytosis and nitric oxide production and stimulated endothelin-1 secretion by lung lavage cells but did not modify secretion of macrophage inflammatory protein-2. Co-exposure to particles potentiated the ozone-induced septal cellularity in the central acinus but without measurable exacerbation of the ozone-related alveolar neutrophilia and permeability to protein detected by lung lavage. The enhanced septal thickening was associated with elevated production of both macrophage inflammatory protein-2 and endothelin-1 by lung lavage cells. Interestingly, inhalation of urban particulate matter increased the plasma levels of endothelin-1, but this response was not influenced by the synergistic effects of ozone and particles on centriacinar septal tissue changes. This suggests an impact of the distally distributed particulate dose on capillary endothelial production or filtration of the vasoconstrictor. Overall, equivalent patterns of effects were observed after a single exposure or three consecutive daily exposures to the pollutants. The experimental data are consistent with epidemiological evidence for acute pulmonary effects of ozone and respirable particulate matter and suggest a possible mechanism whereby cardiovascular effects may be induced by particle exposure. In a broad sense, acute biological effects of respirable particulate matter from ambient air appear related to paracrine/endocrine disruption mechanisms.

Animals↗

PubMed2006

Air pollution and very low birth weight infants: a target population?

OBJECTIVE: The goal was to examine systematically the association between maternal exposure to particulate matter of <10 microm and very low birth weight (<1500 g) delivery for evidence of an effect on duration of gestation and/or intrauterine growth restriction. METHODS: This case-control study took place between April 1, 1986, and March 30, 1988, in Georgia Health Care District 9 and included 128 mothers of very low birth weight infants, all of whom were preterm and were classified as either small for gestational age or appropriate for gestational age, and 197 mothers of term, appropriate-for-gestational-age infants weighing > or = 2500 g. Maternal exposure to particulate matter of <10 microm was estimated with 2 exposure measures, namely, a county-level measure based on residence in a county with an industrial point source and an environmental transport model based on the geographic location of the birth home. RESULTS: Considering preterm/appropriate-for-gestational-age infants as cases and term/appropriate-for-gestational-age infants as controls, adjusted odds ratios for maternal exposure to particulate matter of <10 microm were statistically significant (adjusted odds ratio for county-level model: 4.31; adjusted odds ratio for environmental transport model: 3.68). Although elevated, no statistically significant association was found between maternal exposure and preterm/appropriate-for-gestational-age delivery when compared to preterm/small-for-gestational-age delivery. CONCLUSIONS: There are increased odds of maternal exposure to ambient particulate matter of <10 microm for very low birth weight preterm/appropriate-for-gestational-age delivery, compared with term/appropriate-for-gestational-age delivery, which suggests that the observed association between maternal exposure to air pollution and low infant birth weight (particularly <1500 g) is at least partially attributable to an effect on duration of gestation.

Air Pollutants↗

PubMedDate not supplied

GC/ITMS measurement of carbonyls and multifunctional carbonyls in PM2.5 particles emitted from motor vehicles.

A method was developed and tested to identify and quantitate carbonyls and multifunctional carbonyls in fine particulate matter (PM2.5; <2.5 microm aerodynamic diameter). The method relies on ultrasonic extraction of particulate matter on filters at -8 degrees C; derivatization with O-(2,3,4,5,6-pentafluorobenzyl) hydroxylamine (PFBHA), and PFBHA along with bis (trimethylsilyl) trifluoroacetamide (BSTFA); and detection of the derivatives by gas chromatography/ion trap mass spectrometry. Ultrasonic extraction of model compounds from enriched particles was affected by solvent polarity (water > methylene chloride > toluene-isopropanol (2 + 1, v/v). Water provided the highest recovery for dihydroxy acetone, pyruvic acid, and hydroxy acetone, compared to methylene chloride, and toluene-isopropanol. Lowering the ultrasonication bath temperature from 0 degrees to -8 degrees C improved the recoveries of the less water soluble and more volatile species-methacrolein, methyl vinyl ketone, 2,3-butanedione, and tolualdehyde. The power of the method was demonstrated by identification and quantitation of carbonyls and multifunctional carbonyls in sample extracts of fine particulate matter (PM2.5) collected in the Caldecott tunnel, CA. The identities of crotonaldehyde, 2,3-butanedione, glyoxal, 9H-fluoren-9-one, glycolaldehyde, glyoxylic acid, levulinic acid, and 3-hydroxybenzaldehyde were confirmed by comparing the relative retention time and mass spectra of the analyte in the sample extract with an authentic standard. Quantitation of crotonaldehyde, glyoxal, 2,3-butanedione, glyoxylic acid, and levulinic acid was accomplished. This is the first report of glyoxylic acid, levulinic acid, and 3-hydroxybenzaldheyde in PM2.5 particles sampled in a roadway tunnel. It is also the first report of a C10 carbonyl with the molecular formula of C10H16O2, a hydroxy carbonyl with the molecular formula of C17H21NO2, and a hydroxy or dihydroxy carbonyl with the molecular formula of C16H14O2 or C9H10O3. The high-molecular weight hydroxy carbonyls, which were found only in the heavy-duty (diesel) bore, may be tracers of diesel emissions in air.

Air Pollutants↗

PubMed2003

Determination of digesta flow entering the omasal canal of dairy cows using different marker systems.

Four studies were conducted to compare the effect of four indigestible markers (LiCoEDTA, Yb-acetate, Cr-mordanted straw and indigestible neutral-detergent fibre (INDF)) and three marker systems on the flow of digesta entering the omasal canal of lactating dairy cows. Samples of digesta aspirated from the omasal canal were pooled and separated using filtration and high-speed centrifugation into three fractions defined as the liquid phase, small particulate and large particulate matter. Co was primarily associated with the liquid phase, Yb was concentrated in small particulate matter, whilst Cr and INDF were associated with large particles. Digesta flow was calculated based on single markers or using the reconstitution system based on combinations of two (Co + Yb, Co + Cr and Co + INDF) or three markers (Co + Yb + Cr and Co + Yb + INDF). Use of single markers resulted in large differences between estimates of organic matter (OM) flow entering the omasal canal suggesting that samples were not representative of true digesta. Digesta appeared to consist of at least three phases that tended to separate during sampling. OM was concentrated in particulate matter, whilst the liquid phase consisted mainly of volatile fatty acids and inorganic matter. Yb was intimately associated with nitrogenous compounds, whereas Cr and INDF were concentrated in fibrous material. Current data indicated that marker systems based on Yb in combination with Cr or INDF are required for the accurate determination of OM, N and neutral-detergent fibre flow. In cases where the flow of water-soluble nutrients entering the omasal canal is also required, the marker system should also include Co.

Animals↗

PubMed2001

Ultrastructural nasal pathology in children chronically and sequentially exposed to air pollutants.

Southwest Metropolitan Mexico City (SWMMC) children are repeatedly exposed to a complex mixture of air pollutants, including ozone, particulate matter, and aldehydes. Nasal biopsies taken from these children exhibit a wide range of histopathologic alterations: marked changes in ciliated and goblet cell populations, basal cell hyperplasia, squamous metaplasia, and mild dysplasias. We studied the ultrastructural features of 15 nasal biopsies obtained from clinically healthy children 4 to 15 yr of age, growing up in SWMMC. The results were compared with nasal biopsies from 11 children growing up in Veracruz and exposed to low pollutant levels. Ultrathin sections of nasal biopsies revealed an unremarkable mucociliary epithelium in control children, whereas SWMMC children showed an epithelium comprised of variable numbers of basal, ciliated, goblet, and squamous metaplastic as well as intermediate cells. Nascent ciliated cells, as evidenced by the presence of migratory kinetosomes, were common, as were ciliary abnormalities, including absent central microtubules, supernumerary central and peripheral tubules, ciliary microtubular discontinuities, and compound cilia. Dyskinesia associated with these abnormal cilia was suggested by the altered orientation of the central microtubules in closely adjacent cilia. A transudate was evident between epithelial cells, suggesting potential deficiencies in epithelial junction integrity. Particulate matter was present in heterolysosomal bodies in epithelial cells and it was also deposited in intercellular spaces. The severe structural alteration of the nasal epithelium together with the prominent acquired ciliary defects are likely the result of chronic airway injury in which ozone, particulate matter, and aldehydes are thought to play a crucial role. The nasal epithelium in SWMMC children is fundamentally disordered, and their mucociliary defense mechanisms are no longer intact. A compromised nasal epithelium has less ability to protect the lower respiratory tract and may potentially leave the distal acinar airways more vulnerable to reactive gases. Impairment of mucociliary clearance has the potential to increase the contact time between deposited mutagenic particulate matter and the epithelial surface, thus increasing the risk for nasal carcinogenesis. Chronic exposures to air pollutants affect the whole respiratory tract; the nasal epithelium is an accessible and valuable sentinel to monitor exposures to toxic or carcinogenic substances.

Adolescent↗

PubMed1997

Combustion products from advanced composite materials.

Recent advances in armament and materials applications are beginning to outpace the development of adequate safety characterizations. To avoid unnecessary and restrictive regulations implemented to protect individuals from potential toxic consequences resulting from exposure to combustion products of advanced composite materials (ACM); this laboratory has begun an investigation of combustion characteristics. In this preliminary investigation we have assessed the production of particulate matter and the production of organic compounds contained in both the combustion vapor phase or associated with the particulate matter. The results of these investigations have revealed that a substantial fraction of the particulates appear to be in the respirable range and that a high number of organic compounds and potential toxicants are associated with particulate matter. These findings are the first to describe the production of potentially toxic atmospheres from the combustion of advanced composite materials and indicate the usefulness of further investigations to quantify the risk of exposure to humans. These and forthcoming data will be useful in determining proper protective equipment and precautions required to protect human health during exposures to products from the combustion of advanced composite materials.

Aniline Compounds↗

PubMed2001

[The effects of ozone and toxic air particles on airway function in mice].

We tested the hypothesis that exposures to particulate matter and ozone can produce asthma-like symptoms. Balb/c mice received a single intratracheal instillation of particulate matter and TiO2 or they were exposed to low concentration of ozone. We have established that exposure to particulate matter produces increased responsiveness to methacholine in mice. Exposure to ozone and TiO2 did not produce changes in respiratory mechanics. These data are spreading our understanding about mechanisms of environmental influence on airways.

Air Pollutants↗

PubMed1997

Identification of historical lead sources in roof dusts and recent lake sediments from an industrialized area: indications from lead isotopes.

X-ray fluorescence and stable lead (Pb) isotopic analyses have been undertaken on dusts, known from microscopic investigation to contain significant quantities of industrially- and urban-derived particulate matter, present in the roof cavities of houses in the Illawarra region (N.S.W., Australia), with the objective of examining the historic record of Pb pollution. All investigated houses contained in excess of 250 micrograms g-1 Pb, with dwellings close to a copper smelter, in a large industrial complex including a major steelworks, containing higher (> 2500 micrograms g-1) Pb concentrations. The isotopic composition in the dusts, expressed here as 206Pb/204Pb, is relatively constant at 17.0, irrespective of dwelling age or distance from the industrial complex. Contamination of the dusts by Pb sourced from paint cannot explain the isotopic uniformity of the dust samples. Isotopic modelling indicates that the dusts contain Pb derived from the copper smelter, gasoline-air Pb and a minor contribution from coal-utilising sources. Lead loading was also investigated in the adjacent lagoon, which acts as a natural sink for particulate matter in the Illawarra region. Isotopic data and modelling indicate that one natural and four anthropogenic sources contribute to the Pb burden of this lagoon. The natural source consists of Permian rocks cropping out in the catchment area which have a 206Pb/204Pb of approximately 18.7. The suggested anthropogenic sources are an old disbanded base-metal (Pb) smelter (206Pb/204Pb approximately 16.2-16.3), the copper smelter (206Pb/204Pb approximately 17.9), gasoline-air derived Pb (206Pb/204Pb approximately 16.4-16.5) and industries utilising coal, for example the recently closed thermal coal-fired power station (206Pb/204Pb approximately 18.9). The relative contributions of the base-metal (mainly lead) smelter and gasoline-air Pb in the sediment can only be partly assessed due to the isotopic similarity of these sources. Likewise the natural background and coal source (e.g. power station) contributions can only be estimated from historical data. Age estimations for sediment cores, using 137Cs, provide some control on these assessments. Near surface sediments in the lagoon have a relatively constant 206Pb/204Pb of 17.6-17.7, irrespective of sample location. Isotopic calculations, together with records of particulate matter pollution emissions, indicate a link between the Pb in roof dusts (206Pb/204Pb approximately 17.0) and Pb contamination of the near surface (upper 20 cm) lagoonal sediments via a homogeneous, non-unique source of lead whose isotopic composition closely matches that of the dusts. Over the last 5 decades, atmospheric fallout of Pb-bearing particulate matter appears to have been the dominant pathway for addition of Pb to the lagoon and dwellings in the Illawarra region.

Australia↗

PubMed1989

[Particulate contamination of infusion solutions and drug additives in the framework of long-term intensive therapy. 2. An animal model].

When IV solutions are used, particulate matter may be introduced into the patient. Using X-ray studies we could demonstrate particulate matter consisting mainly of glass from ampules, rubber from rubber stoppers of infusion bottles, and plastic material from IV sets. With a recently introduced method of back-scatter pictures in scanning electron microscopy combined with X-ray studies--Jeol 35 CF/EEDS II Ortec (REM EDX)--we analyzed this phenomenon using an animal model (rabbit). It appears that particulate matter is deposited in the interstitial lung tissue and especially the pulmonary microcirculation. Pathogenetic effects could also be demonstrated (formation of thrombi, etc.).

Animals↗

PubMed1996

Inhalation of diesel engine exhaust increases bone mineral concentrations in growing rats.

Experiments were conducted to determine whether diesel engine exhaust affects bone metabolism in growing rats. The rats were assigned to three groups: those exposed to total diesel engine exhaust with 5.63 mg/m3 particulate matter, 4.10 ppm nitrogen dioxide, 8.10 ppm nitrogen monoxide; those exposed to filtered exhaust without particulate matter; and those exposed to clean air. Dosing experiments were performed for 3 months beginning at birth (6 h/day for 5 days/week). Bone mineral content (BMC) values in lumbar vertebral bone were significantly increased in both groups exposed to diesel exhaust (P < 0.01) compared to that of rats exposed to clean air. Bone mineral density (BMD) values were also significantly increased in both exposed groups, total exhaust (P < 0.01) and filtered exhaust (P < 0.001), compared to that of rats exposed to clean air. BMD values in the mid-femur were also significantly greater in animals exposed to diesel exhaust, total exhaust (P < 0.05), and filtered exhaust (P < 0.01), compared to that of those exposed to clean air. Urinary excretion of deoxypyridinolines, a biochemical marker for bone resorption, was significantly reduced in animals exposed to total diesel exhaust and filtered exhaust (P < 0.001, P < 0.01) compared to control. There was also a significant difference between the two exposure groups of diesel exhaust (P < 0.05). Since these effects were not inhibited by filtration, the gaseous phase of the exhaust was considered more responsible than particulate matter for reducing bone resorption.

Administration, Inhalation↗

PubMed2005

Use of multi-objective air pollution monitoring sites and online air pollution monitoring system for total health risk assessment in Hyderabad, India.

A consensus has been emerging among public health experts in developing countries that air pollution, even at current ambient levels, aggravates respiratory and cardiovascular diseases and leads to premature mortality. Recent studies have also presented well-founded theories concerning the biological mechanisms involved and the groups of people that are probably more susceptible to health effects caused or exacerbated by inhalation of ambient particulate matter (PM.). On the basis of prognostic studies carried out in Center for Environment, JNT University, Hyderabad "it has been estimated that in Hyderabad some 1,700 to 3,000 people per year die prematurely as a result of inhaling PM". These figures reflect only the effects of acute exposure to air pollution. If the long-term effects of chronic exposure are taken into account, 10,000-15,000 people a year could die prematurely in Hyderabad. This estimate of the chronic effects is based on other studies, which are not completely comparable with the Hyderabad situation. While the study designs and analyses in these other studies may indeed be different or irrelevant to Hyderabad, the fact they were carried out in other countries is irrelevant. Taking into account these considerations, a model for total health risk assessment for the city of Hyderabad, and its state of Andhra Pradesh in India has been developed using a multi-objective air pollution monitoring network and online and real time air pollution monitoring stations. For the model studies a number of potential monitoring sites were screened for general and site-specific criteria in a geographic information system (GIS) environment that may, on a local basis, affect the representativeness of the data collected. Local features that may affect either the chemical or meteorological parameters are evaluated to assure a minimum of interference. Finally, for monitoring air pollution, an online and real-time monitoring system was designed using advanced electrochemical sensor systems (sulphur dioxide, oxides of nitrogen, carbon monoxide, hydrocarbons, ozone, mercaptans and hydrogen sulphide) and a particulate matter analyzer (total suspended particulate matter TSPM), PM2.5 and PM10). The sensor and data acquisition systems are programmed to monitor pollution levels at 1/2 hour durations during peak hours and at 1-hour intervals at other times. Presently, extensive statistical and numerical simulations are being carried out at our center to correlate the individuals living in the monitored areas with respiratory infections with air pollution.

Air Pollutants↗

PubMed2006

Preliminary evaluation of micro-Raman spectrometry for the characterization of individual aerosol particles.

Raman spectrometry has been used to determine the graphitic C content and to estimate particle size and disordered character of the C in aerosol particulate matter collected on filters, with sample spot sizes on the order of 100 microm being analyzed. Individual analysis of particulate matter with aerodynamic diameters less than 10 microm has therefore not been considered. In this investigation, various size fractions of aerosol particulate matter originating from both indoor and outdoor sources were collected by means of impactors or passive dry deposition on different types of substrate and analyzed by means of micro-Raman spectrometry with spot sizes ranging from 1-5 microm. The aim was to investigate the possible application of micro-Raman spectrometry to the molecular characterization of individual aerosol particles and to assess the applicability of the various substrates in such an analysis. It was demonstrated that the molecular characterization of most inorganic particles is trivial, but organic and heterogeneous conglomerates proved to be more challenging. Spectral contributions of the substrates, currently favored for individual particle analysis, were significant. Results obtained from micro Raman spectrometry can certainly add valuable molecular information on individual aerosol particles as small as 1 microm aerodynamic diameter.

Aerosols↗