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PubMed2006

[Determination of 16 PAHs from atmospheric particulate matter PM2.5 in certain ironworks district by HPLC].

The paper describes the determination of the 16 polycyclic aromatic hydrocarbons (PAHs) prescribed by Environmental Protection Agency in PM2.5 in certain ironworks district of Beijing by HPLC. A HPLC method of VWD-FLD connected in series was founded. The 16 PAHs were completely separated by the method. The earlier eluted ten PAHs were detected by VWD and the rest were detected by FLD. The minimum detection limits of the 16 PAHs vary from 0.29 microg x L(-1) (for Bkf) to 50.6microg x L(-1) (for Nap), the average recoveries range between 85.1% (for Nap) and 103.2% (for Fla) and the relative standard deviations are between 4.31% (for Flu) and 9.93% (for Ind). The detection results indicate that the pollution situation is still very serious in this district.

Air Pollutants↗
PubMed2005

Effects of sample preparation on chemistry, cytotoxicity, and inflammatory responses induced by air particulate matter.

Methanol is used for high-efficiency extraction of air particulate (PM) mass from the sampling substrate in the high-volume cascade impactor. Sonication is needed during extraction and when dissolving dried PM samples in liquids used in exposure studies. We investigated the effects of these procedures on the PM chemistry and PM-induced cytotoxic and inflammatory responses in mouse macrophages. Untreated and methanol-treated ambient air reference PM samples (SRM1649a, EHC-93) and diesel PM (SRM1650) were tested after different sonication durations (530 min). Furthermore, the time dependency of the responses to SRM1649a, EHC-93, and a fine PM sample from Helsinki was investigated. Methanol pretreatment increased on average by 24% and 21% the recovery of water-soluble metals from SRM1649a and EHC-93, but not SRM1650. It had no systematic effect on the recoveries of inorganic secondary ions (NO3-, SO4(2-), NH4+) or the sum of genotoxic PAH compounds from the three reference samples. Nitric oxide (NO) response to SRM1650 was strongly enhanced by methanol pretreatment, whereas the cytotoxic or inflammatory responses to the ambient air PM samples (EHC-93, SRM1649a) were only slightly modified. Sonication duration was a modifying factor only in connection to SRM1650. Maximal interleukin (IL)-1 production was observed earlier (8 h) than maximal tumor necrosis factor (TNF) alpha and IL-6 productions (24 h), which indicates the importance to know the optimal time points for measurement of the selected response parameters. In conclusion, methanol extraction and reasonable sonication duration are not likely to modify the cytotoxic and inflammatory potency of ambient air PM samples, but some responses to air PM, rich in organic compounds, can be modified.

Air Pollutants↗
PubMed1994

Total suspended particulate matter and daily mortality in Cincinnati, Ohio.

Recent studies have associated particulate air pollution with daily mortality in a number of U.S. communities. This study sought to replicate those analyses in Cincinnati, Ohio, and to test the strength of the association to the deletion of days with extreme weather conditions and to sensitivity analyses in the analytical approach. This study demonstrates the use of graphical diagnostic procedures to assure adequate control for season and weather and to confirm that the risk is particularly elevated in the elderly and for deaths from pneumonia and cardiovascular disease. Daily total suspended particulate (TSP) concentrations were available in Cincinnati from 1977 to 1982. They were matched to daily counts of nonaccidental deaths, temperature, and dew point temperature. Poisson regression analysis controlled for seasonal and monthly variations and potentially nonlinear relationships to temperature and humidity. TSP was associated with increased risk of mortality. The relative risk for a 100 micrograms/m3 increase in TSP was 1.06 (95% CI = 1.03-1.10). The relative risk for the elderly was higher (1.09), as was the risk for pneumonia (1.18) and cardiovascular disease (1.08). The similarity to recently reported results in Philadelphia is striking. Given the consistent findings from multiple locations, the relationship should be considered causal.

Aged↗
PubMed1983

Particulate matter in four reconstituted cephalosporin injections.

The amount and size of particulate contamination in three commercially available cephalosporin injections and a new product, anophilized cephalothin sodium injection, were studied. Particles in reconstituted cephalothin sodium (commercially available and anophilized), cephapirin sodium, and cephradine injections were counted using two methods: (1) modified USP membrane-filtration technique and (2) Elzone computerized particle analyzer. The amount of particulate contamination in the ranges of 10-24 and greater than or equal to 25 microns was determined by both methods. In the 10-24-microns range, the cephalothin, cephapirin, and cephradine products had significantly greater particle counts than the anophilized cephalothin product. The greater than or equal to 25-microns particle counts showed that the cephapirin and cephradine products had particle counts greater than the anophilized cephalothin product, while total particle counts showed the same results as the 10-24-microns particle counts. A comparison of counting methods showed that the only significant difference between the number of particulates obtained using the modified USP and Elzone computer methods was with the cephalothin product. Anophilized cephalothin sodium injection has significantly fewer particles in the size ranges studied. No conclusion could be reached as to the more accurate method for counting particles.

Cephalosporins↗
PubMed2006

Concentration and emission sources of airborne metals in particulate matter in the industrial district of Médio Paraíba, state of Rio de Janeiro, Brazil.

Total suspended particles and 12 airborne metals were determined in 4 sampling sites in the industrial region of Médio Paraíba, Brazil. The geometrical means for the four sampling locals were (in units of microg/m3): 65.9 in Barra Mansa, 57.3 in Jardim Paraíba (Volta Redonda), 41.7 in Resende, and 48.9 in Volta Grande (Volta Redonda). These values are lower than levels previously determined in urban and industrial locals of the Metropolitan Area of Rio de Janeiro. For metals, the higher concentrations were obtained for Ca, Zn, Al, Fe, and Mg. Ca, Zn, and Al levels are higher than those determined in other industrial areas. These three metals are used in steel manufacturing, the main economical activity of the region. Enrichment factors for Zn, Cu, Cd, and Pb are higher than 10, suggesting an industrial input. Statistical analysis show a high correlation among Ca, Mg, Zn, Cr, Al, Mn, and Fe, all of them used as raw materials in steel manufacturing and/or accumulated as industrial blast furnace slag and steelworks slag.

Aluminum↗
PubMed2005

Dissolution and solubility of trace metals from natural and anthropogenic aerosol particulate matter.

An open flow reactor is used to simulate the dissolution process of mineral aerosol particles in atmospheric water droplets. Data on dissolution kinetic and solubility are provided for the major trace metals from two kinds of matrix: alumino-silicated and carbonaceous sample. The results emphasise that the metals contained in the carbonaceous aerosols are easier dissolved than in the alumino-silicated particles. The released concentrations are not related to the total metal composition or the origin of particles, but are directly associated with the type of liaisons whereby the metals are bound in the solid matrix. Thus, the metals coming from carbonaceous particles are adsorbed impurities or salts and hence are very soluble and with a dissolution hardly dependent on pH, whereas the metals dissolved from alumino-silicated particles are less soluble, notably the ones constitutive of the matrix network (Fe, Mn), and with a dissolution highly influenced by pH. Consequently, in the regions with an anthropogenic influence, the dissolved concentrations of metals found in the atmospheric waters are mainly governed by the elemental carbon content. Moreover, it appears that the dissolution kinetic of metals is not constant as a function of time. The dissolution rates are very rapid in the first 20 min of leaching and then they are stabilised to lower values in comparison to initial rates. By consequence, the total dissolved metal content is provided after the first 20 min of the droplet lifetime. For this reason, the effects of trace metals on the atmospheric aqueous chemistry and as atmospheric wet input to the marine biota are maximal for "aged" droplets.

Aerosols↗
PubMed2006

Urban background particulate matter and allergic sensitization in adults of ECRHS II.

BACKGROUND: Epidemiological studies have shown weak or inconsistent associations between ambient air pollutants and allergic sensitization. The aim of this study was to evaluate whether regional urban air pollution may partly explain the large variation in the prevalence of allergic sensitization across cities of the European Community Respiratory Health Survey (ECRHS) II. METHODS: ECRHS is a cross-sectional survey initiated in 29 countries across Europe in the 1990s (ECRHS I) with a follow-up conducted 10 years later (ECRHS II). Subject characteristics were measured by questionnaires and blood tests conducted for the measurement of specific immunoglobulin E. Fine particle mass (PM(2.5), <2.5 microm) and sulphur on PM(2.5) were measured in 21 centres and annual averages of urban regional background air pollution were calculated. Results were scaled by an interquartile range increase in ambient PM(2.5) (6.03 microg/m(3)) and sulphur (1336 ng/m(3)). Generalized estimating equations were applied to compute population average effect estimates with adjustment for age, gender, smoking habit, education and number of siblings. RESULTS: A notable variation in pollution level and prevalence of allergic sensitization was observed. Moreover, exposure to urban regional background air pollution was not associated with allergic sensitization; adjusted odds ratios and 95% confidence interval were 1.02 (0.95-1.09) for PM(2.5) and 1.08 (0.86-1.31) for sulphur. These statistically non-significant associations were sensitive to model specification. CONCLUSIONS: The study suggests that regional air pollution measured at fixed sites is not associated with allergic sensitization among adults in ECRHS II.

Adult↗
PubMed2006

Arsenic speciation of atmospheric particulate matter (PM10) in an industrialised urban site in southwestern Spain.

An arsenic speciation study has been performed in PM10 samples collected on a fortnight basis in the city of Huelva (SW Spain) during 2001 and 2002. The arsenic species were extracted from the PM10 filters using a NH2OH x HCl solution and sonication, and determined by HPLC-HG-AFS. The mean bulk As concentration of the samples analyzed during 2001 and 2002 slightly exceed the mean annual 6 ng m(-3) target value proposed by the European Commission for 2013, arsenate [As(V)] being responsible for the high level of arsenic. The speciation analyses showed that As(V) was the main arsenic species found, followed by arsenite [As(III)] (mean 6.5 and 7.8 ng m(-3) for As(V), mean 1.2 and 2.1 ng m(-3) for As(III), in 2001 and 2002, respectively). The high levels of arsenic species found in PM10 in Huelva have a predominant industrial origin, such as the one from a nearby copper smelter, and do not present a seasonal pattern. The highest daily levels of arsenic species correspond to synoptic conditions in which the winds with S and SW components transport the contaminants from the main emission source. The frequent African dust outbreaks over Huelva may result in an increment of mass levels of PM10, but do not represent a significant input of arsenic in comparison to the anthropogenic source. The rural background levels of arsenic around Huelva are rather high, in comparison to other rural or urban areas in Spain, showing a relatively high atmosphere residence time of arsenic. This work shows the importance of arsenic speciation in studies of aerosol chemistry, due to the presence of arsenic species [As(III) and As(V)] with distinct toxicity.

Air Pollutants↗
PubMed2005

Concentrations, enrichment and predominant sources of Sb and other trace elements in size classified airborne particulate matter collected in Tokyo from 1995 to 2004.

APM was collected and trace elements existing in the particles were monitored since May 1995 in this study. APM sample was collected separately by size (d < 2 microm, 2-11 microm and >11 microm) on the roof of the university building (45 m above ground) in the campus of Faculty of Science and Engineering, Chuo University, Tokyo, Japan, using an Anderson low volume air sampler. The collected sample was digested by HNO3, H2O2 and HF using a microwave oven, and major elements (Na, Mg, Al, K, Ca and Fe) were measured by ICP-AES, and trace elements (Li, Be, Ti, V, Cr, Mn, Co, Ni, Cu, Zn, As, Se, Mo, Cd, Sb, Ba and Pb) were measured by ICP-MS. It was observed that the APM concentration was higher between the winter and the spring, compared to during the summer. The enrichment factor was calculated for each element in each set of APM (d < 2 microm, 2-11 microm and >11 microm). Seasonal trends of enrichment factors were examined, and the elements were classified into 3 groups according to the common seasonal behavior. It is likely that the elements in the same group have common origins. Toxic pollutant elements (Sb, Se, Cd, Pb and As) were found in small particles with d of <2 microm in concentrated levels. Antimony (Sb) had the highest enrichment factor, and the results suggested that Sb level in APM was extremely high. The origins of Sb were sought, and wastes from plastic incineration and brake pad wears of automobiles were suspected. Each set of APM (d < 2 microm, 2-11 microm and >11 microm) was classified by the shape, and the shape-dependent constituents of a single APM particle were quantitatively measured by SEM-EDX. High concentration of Sb was found in APM <2 microm and square particles. Particles less than 2 microm and square shaped particles were major particles produced by actual car braking experiments. From these experimental results it was concluded that the source of Sb in squared APM <2 microm is considered to be from brake pad wear.

Air Pollutants↗
PubMed2003

Bioavailability of the organophosphorous insecticide chlorpyrifos to the suspension-feeding bivalve, Mercenaria mercenaria, following exposure to dissolved and particulate matter.

Under estuarine conditions, hydrophobic pesticides undergo physical/chemical partitioning into dissolved and particulate fractions of sediments. Our experimental study using 14C-chlorpyrifos (14C-CHPY) showed that sorptive associations of this common insecticide with particulate (>0.2 microm) and dissolved fractions (<0.2 microm) of sediments strongly influenced uptake, tissue absorption, and elimination in the estuarine bivalve Mercenaria mercenaria. Bivalves were fed algae mixed with particulate and dissolved fractions of 14C-CHPY-contaminated estuarine sediment particles, components of estuarine sediments (silica, humic acids), and a naturally occurring food source (phytoplankton) to quantify relative uptake, tissue absorption efficiencies, and elimination of 14C-CHPY. Measurements of 14C-CHPY tissue absorption efficiencies (AE%) indicated that particle source qualities influenced much of the insecticide bioavailability. Mean tissue AE% of 14C-CHPY associated with different particulate fractions ranged from 23 to 31%, while uptake from the dissolved/colloidal forms resulted in low (7-17%) AE%. Our data indicated that 14C-CHPY is more likely to bioaccumulate through ingestion of contaminated particulate material than through filtration/ingestion of dissolved/colloidal material. The high selectivity and digestibility of algae particles by M. mercenaria, a potentially ingested food source, may play an important role in the bioavailability of chlorpyrifos in this animal.

Animals↗
PubMed2003

Assessment of lead, zinc, copper, nickel and chromium in total suspended particulate matter from the workplace in Al-Rusayl Industrial Estate, Oman.

Total suspended particulates (TSP) were collected with a high volume sampler from the indoor work environment of 23 industries in Al-Rusayl Industrial Estate in Muscat, Oman. The values measured ranged from 39 microg m(-3) to 1033 microg m(-3). TSP in the ambient air of the area was found to have an average value of 1802 microg m(-3). TSP were analyzed for Pb, Cu, Ni, Zn and Cr. Compared to other metals, Pb emission was high with values ranging from 3 to 15 109 ng m(-3) with the mean value being 1 293 ng m(-3); Cu concentration varied from 3 to 2600 ng m(-3) with a mean value of 131 ng m(-3); Ni concentration ranged from 6 to 46 ng m(-3) with a mean value of 17 ng m(-3); Cr concentration ranged from 1 to 133 ng m(-3) with a mean value of 23 ng m(-3) while that of Zn varied from 0.01 to 1 978 ng m(-3) with the mean value being 464 ng m(-3). The concentrations of Pb, Ni, Cu, Cr, and Zn in the ambient air were also measured and found to have the following values: 122, 18, 16, 5 and 0.01 ng m(-3), respectively. These values indicate that the industries in the area do not contribute significantly to heavy metal air pollution.

Air Pollution, Indoor↗
PubMed2003

Particulate emission inventory and trends in ambient particulate matter concentrations in the Czech Republic between 1993 and 1999.

Trends in total suspended particulates (TSP) emission inventories were compared with ambient TSP concentrations during the period of 1993-1999 in the Czech Republic. The TSP annual emission decreased within the period of observation from 441,300 to 67,000 of metric tonnes (by 85%). During the same period a less pronounced downward trend from 80.3 microg m(-3) to 31.5 microg m(-3) (decrease by 61%) was noted also for the ambient TSP annual average. Difference between the two air quality indicators seems to indicate that changes in TSP emission inventories from year to year are being to some extent overestimated. Monthly ambient particulate concentrations did not respond to overall drop in emissions proportionately but were closely associated with monthly mean temperatures. While in the winter the correlation between ambient TSP and temperature was negative, in summer the correlation between the two variables was positive. In spring and autumn there was no clear correlation between temperature and ambient particulate pollution. The improvement of air quality in the Czech Republic since the economical and political transformation in 1990s is substantial when demonstrated by emission figures, however, true state of particulate pollution expressed by ambient levels requires further attention.

Air Pollutants↗
PubMed2006

A predictive model for copper partitioning to suspended particulate matter in river waters.

A chemical equilibrium-based predictive model expressing Cu partitioning as a function of aqueous and solid phase characteristics was developed. The model takes into account only the most important factors that govern Cu partitioning, and therefore results in a relatively simple formulation. It assumes particulate organic carbon (POC) and dissolved organic carbon (DOC) binding sites play the most important role in solid and aqueous phases. The model formulation assumed one-surface site and two dissolved organic matter (DOM) sites, and included the "solids effect". Proton effects were considered for both the particle surface sites and the DOM. The model was calibrated with data for samples collected from the Susquehanna River, and validated with White Clay Creek and Delaware River samples. Copper partitioning in natural water systems with different pH, and concentrations of alkalinity, DOC, POC, total suspended solids (TSS), and total copper was predicted reasonably well.

Binding Sites↗
PubMed2003

Canada Wide Standard for particulate matter and ozone: cost-benefit analysis using a Life Quality Index.

The adverse impacts of particulate air pollution and ground-level ozone on public health and the environment have motivated the development of Canada Wide Standards (CWS) on air quality. In cost-benefit analysis of air-quality options, valuation of reduction in mortality is a critical step as it accounts for almost 80% of the total benefits and any bias in its evaluation can significantly skew the outcome of the analysis. The overestimation of benefits is a source of concern since it has the potential of diverting valuable resources from other needs to support broader health care objectives, education, and social services that contribute to enhanced quality of life. We have developed a framework of reasoning for the assessment of risk-reduction initiatives that would support the public interest and enhance safety and quality of life. This article presents the Life Quality Index (LQI) as a tool to quantify the level of expenditure beyond which it is no longer justifiable to spend resources in the name of safety. It is shown that the LQI is a compound social indicator comprising societal wealth and longevity, and it is also equivalent to a utility function consistent with the basic principles of welfare economics and decision analysis. The LQI approach overcomes several shortcomings of the method used by the CWS Development Committee and provides guidance on the compliance costs that can be justified to meet the Standards.

Air Pollutants↗
PubMed1976

Residues in antibiotic preparations, ii: effect of pH on the nature and level of particulate matter in sodium cephalothin intravenous solutions.

The effect of pH on the extent and nature of particulate contamination in sodium cephalothin intravenous solutions was studied. The extent of particulate contamination was determined by microscopic and automatic electronic counting procedures, and the physical nature of the particles was determined using scanning electron microscopy. At low pH values (i.e., 4.9--5.9), an amorphous residue was predominant, while at higher pH values (6.9--7.8), the gelatinous nature of the residue disappeared and small crystalline particulates of varying sizes were predominant. The level of particulate contamination (particles over 10 mum in size) decreased with an increase in pH to a minimum level between pH 7 and 8. Advice is given to practitioners regarding the preparation of sodium cephalothin solutions.

Cephalothin↗
PubMedDate not supplied

Pulmonary function and ambient particulate matter: epidemiological evidence from NHANES I.

The relationship between pulmonary function and quarterly average levels of total suspended particulates (TSP) was examined for adults who resided in 49 of the locations where the First National Health and Nutrition Examination Survey (NHANES I) was conducted. Statistically significant relationships were observed between TSP levels and forced vital capacity (FVC) and forced expiratory volume at one second (FEV1.0). These relationships remained strong across several specifications and sample changes, e.g., exclusion of cities with two highest and two lowest TSP levels, restriction of sample to whites only. Anthropometric measurements and socioeconomic characteristics of the subjects were included in the analysis, and we restricted the sample to "never" smokers. The results indicate a 1 standard deviation increase (about 34 micrograms/m3) in TSP from the sample mean of 87 micrograms/m3 was associated with an average decrease in FVC of 2.25%. The results of this analysis also suggest that there is a threshold level (i.e., approximately 60 micrograms/m3 [quarterly average]) of TSP below which a relationship with pulmonary function ceases to exist.

Adult↗
PubMedDate not supplied

Characterization of particulate matter in carbon-graphite/epoxy advanced composite material smoke.

The physical and chemical properties of the particulate fraction of carbon-graphite/epoxy advanced composite material (cgeACM) smoke were measured to address concerns regarding potential health hazards posed by the release of fibers during pyrolysis of this material. Filter, low-pressure cascade impactor, and electrostatic precipitator samples were collected from cgeACM smoke in which the aerosol concentration ranged from 0.20 to 5.39 g/m3. Fibers were found in the smoke among individual, spherical, or nearly spherical particles and chain aggregates. The fibers had a mean count diameter of 0.54 micron and an average length of 2.84 microns. However, fibers accounted for approximately 0.3% of the particles counted. The smoke aerosols (including fibers) had mass median aerodynamic diameters (MMAD) ranging from 1.4 to 1.9 microns with standard geometric deviations ranging from 1.6 to 1.8, and hence more than 88% of the particles were in the thoracic size range (MMAD < or = 4.0 microns). All particles were composed primarily of carbon, silicon, sulfur, and oxygen with traces of other metals. By comparison fibers were composed almost exclusively of silicon.

Air Pollutants↗