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Sample records for exhaust particle exposure

  1. Effect of exposure to diesel exhaust particles on the susceptibility of the lung to infection.

    PubMed Central

    Castranova, V; Ma, J Y; Yang, H M; Antonini, J M; Butterworth, L; Barger, M W; Roberts, J; Ma, J K

    2001-01-01

    There are at least three mechanisms by which alveolar macrophages play a critical role in protecting the lung from bacterial or viral infections: production of inflammatory cytokines that recruit and activate lung phagocytes, production of antimicrobial reactive oxidant species, and production of interferon (an antiviral agent). In this article we summarize data concerning the effect of exposure to diesel exhaust particles on these alveolar macrophage functions and the role of adsorbed organic chemicals compared to the carbonaceous core in the toxicity of diesel particles. In vitro exposure of rat alveolar macrophages to diesel exhaust particles decreased the ability of lipopolysaccharide (LPS), a bacterial product] to stimulate the production of inflammatory cytokines interleukin-1 (IL-1) and tumor necrosis factor-alpha (TNF-alpha). Methanol extract exhibited this potential but methanol-washed diesel particles did not. Exposure of rats to diesel exhaust particles by intratracheal instillation also decreased LPS-induced TNF-alpha and IL-1 production from alveolar macrophages. In contrast, carbon black did not exhibit this inhibitory effect. Exposure of rats to diesel exhaust particles by inhalation decreased the ability of alveolar macrophages to produce antimicrobial reactive oxidant species in response to zymosan (a fungal component). In contrast, exposure to coal dust increased zymosan-stimulated oxidant production. In vivo exposure to diesel exhaust particles but not to carbon black decreased the ability of the lungs to clear bacteria. Inhalation exposure of mice to diesel exhaust particles but not to coal dust depressed the ability of the lung to produce the antiviral agent interferon and increased viral multiplication in the lung. These results support the hypothesis that exposure to diesel exhaust particles increases the susceptibility of the lung to infection by depressing the antimicrobial potential of alveolar macrophages. This inhibitory effect appears

  2. NASAL RESPONSES IN ASTHMATIC AND NONASTHMATIC SUBJECTS FOLLOWING EXPOSURE TO DIESEL EXHAUST PARTICLES

    EPA Science Inventory

    Asthma rates have been increasing world-wide, and exposure to diesel exhaust particles may be implicated in this increase. Additionally DEP may also play a role in the increased morbidity and mortality associated with ambient airborne PM exposure. Two types of nasal responses hav...

  3. Diesel and biodiesel exhaust particle effects on rat alveolar macrophages with in vitro exposure

    PubMed Central

    Bhavaraju, Laya; Shannahan, Jonathan; William, Aaron; McCormick, Robert; McGee, John; Kodavanti, Urmila; Madden, Michael

    2014-01-01

    Combustion emissions from diesel engines emit particulate matter which deposits within the lungs. Alveolar macrophages (AM) encounter the particles and attempt to engulf the particles. Emissions particles from diesel combustion engines have been found to contain diverse biologically active components including metals and polyaromatic hydrocarbons which cause adverse health effects. However little is known about AM response to particles from the incorporation of biodiesel. The objective of this study was to examine the toxicity in Wistar Kyoto rat AM of biodiesel blend (B20) and low sulfur petroleum diesel (PDEP) exhaust particles. Particles were independently suspended in media at a range of 1–500µg/mL. Results indicated B20 and PDEP initiated a dose dependent increase of inflammatory signals from AM after exposure. After 24hr exposure to B20 and PDEP gene expression of cyclooxygenase-2 (COX-2) and macrophage inflammatory protein 2 (MIP-2) increased. B20 exposure resulted in elevated prostaglandin E2 (PGE2) release at lower particle concentrations compared to PDEP. B20 and PDEP demonstrated similar affinity for sequesteration of PGE2 at high concentrations, suggesting detection is not imparied. Our data suggests PGE2 release from AM is dependent on the chemical composition of the particles. Particle analysis including measurments of metals and ions indicate B20 contains more of select metals than PDEP. Other particle components generally reduced by 20% with 20% incoporation of biodiesel into original diesel. This study shows AM exposure to B20 results in increased production of PGE2 in vitro relative to diesel. PMID:24268344

  4. Diesel Exhaust Particle Exposure Causes Redistribution of Endothelial Tube VE-Cadherin

    PubMed Central

    Chao, Ming-Wei; Kozlosky, John; Po, Iris P.; Strickland, Pamela Ohman; Svoboda, Kathy K. H.; Cooper, Keith; Laumbach, Robert; Gordon, Marion K.

    2010-01-01

    Whether diesel exhaust particles (DEPs) potentially have a direct effect on capillary endothelia was examined by following the adherens junction component, vascular endothelial cell cadherin (VE-cadherin). This molecule is incorporated into endothelial adherens junctions at the cell surface, where it forms homodimeric associations with adjacent cells and contributes to the barrier function of the vasculature (Dejana et al., 2008; Venkiteswaran et al., 2002; Villasante et al., 2007). Human umbilical vein endothelial cells (HUVECs) that were pre-formed into capillary-like tube networks in vitro were exposed to DEPs for 24 hr. After exposure, the integrity of VE-cadherin in adherens junctions was assessed by immunofluorescence analysis, and demonstrated that increasing concentrations of DEPs caused increasing redistribution of VE-cadherin away from the cell-cell junctions toward intracellular locations. Since HUVEC tube networks are three-dimensional structures, whether particles entered the endothelial cells or tubular lumens was also examined. The data indicate that translocation of the particles does occur. The results, obtained in a setting that removes the confounding effects of inflammatory cells or blood components, suggest that if DEPs encounter alveolar capillaries in vivo, they may be able to directly affect the endothelial cell-cell junctions. PMID:20887764

  5. BIOMARKERS OF DIESEL EXHAUST PARTICLES

    EPA Science Inventory

    The objective of this project is to examine the detectability of some chemical components of diesel exhaust particles (DEP) in human urine following controlled human diesel exposures (IRB-approved). Ultimately, and upon validation, we propose to apply these components as biomarke...

  6. Controlled human exposures to diesel exhaust

    EPA Science Inventory

    Diesel exhaust (DE) is a complex mixture of gaseous and particulate compounds resulting from an incomplete combustion of diesel fuel. Controlled human exposures to DE and diesel exhaust particles (DEP) have contributed to understanding health effects. Such exposure studies of h...

  7. Fucoidan Extracted from Hijiki Protects Brain Microvessel Endothelial Cells Against Diesel Exhaust Particle Exposure-Induced Disruption.

    PubMed

    Choi, Young-Sook; Eom, Sang-Yong; Kim, In-Soo; Ali, Syed F; Kleinman, Michael T; Kim, Yong-Dae; Kim, Heon

    2016-05-01

    This study was performed to evaluate the protective effects of fucoidan against the decreased function of primary cultured bovine brain microvessel endothelial cells (BBMECs) after exposure to diesel exhaust particles (DEPs). BBMECs were extracted from bovine brains and cultured until confluent. To evaluate the function of BBMECs, we performed a permeability test using cell-by-cell equipment and by Western blot analysis for zonular occludens-1 (ZO-1), which is a tight junction protein of BMECs, and evaluated oxidative stress in BBMECs using the DCFH-DA assay and the CUPRAC-BCS assay. The increased oxidative stress in BBMECs following DEP exposure was suppressed by fucoidan. In addition, permeability of BBMECs induced by DEP exposure was decreased by fucoidan treatment. Our results showed that fucoidan protects against BBMEC disruption induced by DEP exposure. This study provides evidence that fucoidan might protect the central nervous system (CNS) against DEP exposure. PMID:27152978

  8. Exposure to allergen and diesel exhaust particles potentiates secondary allergen-specific memory responses promoting asthma susceptibility

    PubMed Central

    Brandt, Eric B.; Biagini Myers, Jocelyn M.; Acciani, Thomas H.; Ryan, Patrick H.; Sivaprasad, Umasundari; Ruff, Brandy; LeMasters, Grace K.; Bernstein, David I.; Lockey, James; LeCras, Timothy D.; Khurana Hershey, Gurjit K.

    2015-01-01

    Background Exposure to traffic pollution particulate matter, predominantly diesel exhaust particles (DEP), increases risk for asthma and asthma exacerbation, however the underlying mechanisms remain poorly understood. Objective To examine the impact of DEP exposure on the generation and persistence of allergen-specific memory T-cells in asthma and translate these findings by determining the impact of early DEP exposure on the prevalence of allergic asthma in children. Methods The impact of DEP on HDM-specific memory responses was determined using an asthma model. Data from children enrolled in the Cincinnati Childhood Allergy and Air Pollution Study (CCAAPS) birth cohort were analyzed to determine the impact of the DEP exposure on asthma outcomes. Results DEP co-exposure with HDM resulted in persistent Th2/Th17 CD127+ effector/memory cells in the lungs, spleen and lymph nodes of adult and neonatal mice. After 7 weeks of rest, a single exposure to HDM resulted in airway hyperresponsiveness and increased levels of Th2 cytokines in only mice that had been previously exposed to both HDM and DEP versus HDM alone. Based on these data, we examined whether DEP exposure was similarly associated increased asthma prevalence in children in the presence or absence of allergen exposure/sensitization in the CCAAPS birth cohort. Early life exposure to high DEP was associated with significantly increased asthma prevalence among allergic children, but not among non-allergic children. Conclusion These findings suggest that DEP exposure results in accumulation of allergen specific Th2/Th17 cells in the lungs, potentiating secondary allergen recall responses and promoting the development of allergic asthma. PMID:25748065

  9. Diesel exhaust exposures in port workers.

    PubMed

    Debia, Maximilien; Neesham-Grenon, Eve; Mudaheranwa, Oliver C; Ragettli, Martina S

    2016-07-01

    Exposure to diesel engine exhaust has been linked to increased cancer risk and cardiopulmonary diseases. Diesel exhaust is a complex mixture of chemical substances, including a particulate fraction mainly composed of ultrafine particles, resulting from the incomplete combustion of fuel. Diesel trucks are known to be an important source of diesel-related air pollution, and areas with heavy truck traffic are associated with higher air pollution levels and increased public health problems. Several indicators have been proposed as surrogates for estimating exposures to diesel exhaust but very few studies have focused specifically on monitoring the ultrafine fraction through the measurement of particle number concentrations. The aim of this study is to assess occupational exposures of gate controllers at the port of Montreal, Canada, to diesel engine emissions from container trucks by measuring several surrogates through a multimetric approach which includes the assessment of both mass and number concentrations and the use of direct reading devices. A 10-day measurement campaign was carried out at two terminal checkpoints at the port of Montreal. Respirable elemental and organic carbon, PM1, PM2.5, PMresp (PM4), PM10, PMtot (inhalable fraction), particle number concentrations, particle size distributions, and gas concentrations (NO2, NO, CO) were monitored. Gate controllers were exposed to concentrations of contaminants associated with diesel engine exhaust (elemental carbon GM = 1.6 µg/m(3); GSD = 1.6) well below recommended occupational exposure limits. Average daily particle number concentrations ranged from 16,544-67,314 particles/cm³ (GM = 32,710 particles/cm³; GSD = 1.6). Significant Pearson correlation coefficients were found between daily elemental carbon, PM fractions and particle number concentrations, as well as between total carbon, PM fractions and particle number concentrations. Significant correlation coefficients were found between particle number

  10. Alteration of intracellular cysteine and glutathione levels in alveolar macrophages and lymphocytes by diesel exhaust particle exposure.

    PubMed Central

    Al-Humadi, Nabil H; Siegel, Paul D; Lewis, Daniel M; Barger, Mark W; Ma, Jane Y C; Weissman, David N; Ma, Joseph K H

    2002-01-01

    The purpose of this study was to characterize the effects of diesel exhaust particles (DEP) on thiol regulation in alveolar macrophages (AM) and lymphocytes. We obtained AM and lymph node (thymic and tracheal) cells (LNC) (at different time points) from rats exposed intratracheally to DEP (5 mg/kg) or saline, and measured inflammatory markers, thiol levels, and glutathione reductase (GSH-R) activity. DEP exposure produced significant increases in neutrophils, lactate dehydrogenase, total protein, and albumin content in the lavage fluid. AM from DEP-exposed rats showed a time-dependent increase in intracellular cysteine (CYSH) and GSH. In LNC the intracellular GSH reached peak level by 24 hr, declining toward control levels by 72 hr after exposure. LNC-CYSH and AM-CYSH and GSH were increased at both 24 and 72 hr. Both Sprague-Dawley and Brown Norway rats showed similar trends of responses to DEP exposure as per measurement of the inflammatory markers and thiol changes. AM and, to a lesser degree, LNC were both active in cystine uptake. The DEP exposure stimulated GSH-R activity and increased the conversion of cystine to CYSH in both cell types. The intracellular level of GSH in DEP-exposed AM was moderately increased compared with the saline control, and was further augmented when cells were incubated with cystine. In contrast, the intracellular level of GSH in DEP-exposed LNC was significantly reduced despite the increased CYSH level and GSH-R activity when these cells were cultured for 16 hr. DEP absorbed 23-31% of CYSH, cystine, and GSH, and only 8% of glutathione disulfide when incubated in cell free media. These results indicate that DEP exposure caused lung inflammation and affected thiol levels in both AM and LNC. PMID:11940452

  11. Diesel and biodiesel exhaust particle effects on rat alveolar machrophages with in vitro exposure

    EPA Science Inventory

    We conducted in vitro exposures of Wistar rat alveolar macrophages (AM) to compare and contrast the toxicity of particulate matter (PM) produced in combustion of biodiesel blend (B20) and petroleum diesel (PDEP). The PM contain detectable levels of transition metals and ions howe...

  12. Anacardic Acids from Cashew Nuts Ameliorate Lung Damage Induced by Exposure to Diesel Exhaust Particles in Mice

    PubMed Central

    Carvalho, Ana Laura Nicoletti; Annoni, Raquel; Torres, Larissa Helena Lobo; Durão, Ana Carolina Cardoso Santos; Shimada, Ana Lucia Borges; Almeida, Francine Maria; Hebeda, Cristina Bichels; Lopes, Fernanda Degobbi Tenorio Quirino Santos; Dolhnikoff, Marisa; Martins, Milton Arruda; Silva, Luiz Fernando Ferraz; Farsky, Sandra Helena Poliselli; Saldiva, Paulo Hilário Nascimento; Ulrich, Cornelia M.; Owen, Robert W.; Marcourakis, Tania; Trevisan, Maria Teresa Salles; Mauad, Thais

    2013-01-01

    Anacardic acids from cashew nut shell liquid, a Brazilian natural substance, have antimicrobial and antioxidant activities and modulate immune responses and angiogenesis. As inflammatory lung diseases have been correlated to environmental pollutants exposure and no reports addressing the effects of dietary supplementation with anacardic acids on lung inflammation in vivo have been evidenced, we investigated the effects of supplementation with anacardic acids in a model of diesel exhaust particle- (DEP-) induced lung inflammation. BALB/c mice received an intranasal instillation of 50 μg of DEP for 20 days. Ten days prior to DEP instillation, animals were pretreated orally with 50, 150, or 250 mg/kg of anacardic acids or vehicle (100 μL of cashew nut oil) for 30 days. The biomarkers of inflammatory and antioxidant responses in the alveolar parenchyma, bronchoalveolar lavage fluid (BALF), and pulmonary vessels were investigated. All doses of anacardic acids ameliorated antioxidant enzyme activities and decreased vascular adhesion molecule in vessels. Animals that received 50 mg/kg of anacardic acids showed decreased levels of neutrophils and tumor necrosis factor in the lungs and BALF, respectively. In summary, we demonstrated that AAs supplementation has a potential protective role on oxidative and inflammatory mechanisms in the lungs. PMID:23533495

  13. Anacardic acids from cashew nuts ameliorate lung damage induced by exposure to diesel exhaust particles in mice.

    PubMed

    Carvalho, Ana Laura Nicoletti; Annoni, Raquel; Torres, Larissa Helena Lobo; Durão, Ana Carolina Cardoso Santos; Shimada, Ana Lucia Borges; Almeida, Francine Maria; Hebeda, Cristina Bichels; Lopes, Fernanda Degobbi Tenorio Quirino Santos; Dolhnikoff, Marisa; Martins, Milton Arruda; Silva, Luiz Fernando Ferraz; Farsky, Sandra Helena Poliselli; Saldiva, Paulo Hilário Nascimento; Ulrich, Cornelia M; Owen, Robert W; Marcourakis, Tania; Trevisan, Maria Teresa Salles; Mauad, Thais

    2013-01-01

    Anacardic acids from cashew nut shell liquid, a Brazilian natural substance, have antimicrobial and antioxidant activities and modulate immune responses and angiogenesis. As inflammatory lung diseases have been correlated to environmental pollutants exposure and no reports addressing the effects of dietary supplementation with anacardic acids on lung inflammation in vivo have been evidenced, we investigated the effects of supplementation with anacardic acids in a model of diesel exhaust particle- (DEP-) induced lung inflammation. BALB/c mice received an intranasal instillation of 50  μ g of DEP for 20 days. Ten days prior to DEP instillation, animals were pretreated orally with 50, 150, or 250 mg/kg of anacardic acids or vehicle (100  μ L of cashew nut oil) for 30 days. The biomarkers of inflammatory and antioxidant responses in the alveolar parenchyma, bronchoalveolar lavage fluid (BALF), and pulmonary vessels were investigated. All doses of anacardic acids ameliorated antioxidant enzyme activities and decreased vascular adhesion molecule in vessels. Animals that received 50 mg/kg of anacardic acids showed decreased levels of neutrophils and tumor necrosis factor in the lungs and BALF, respectively. In summary, we demonstrated that AAs supplementation has a potential protective role on oxidative and inflammatory mechanisms in the lungs. PMID:23533495

  14. Effect of short-term exposure to diesel exhaust particles and carboxylic acids on mitochondrial membrane disruption in airway epithelial cells

    EPA Science Inventory

    Rationale: Diesel exhaust has been shown to induce adverse pulmonary health effects; however, the underlying mechanisms for these effects are still unclear. Previous studies have imlplicated mitochondrial dysfunction in the toxicity of diesel exhaust particles (DEP). DEP contain...

  15. Detailed diesel exhaust characteristics including particle surface area and lung deposited dose for better understanding of health effects in human chamber exposure studies

    NASA Astrophysics Data System (ADS)

    Wierzbicka, Aneta; Nilsson, Patrik T.; Rissler, Jenny; Sallsten, Gerd; Xu, Yiyi; Pagels, Joakim H.; Albin, Maria; Österberg, Kai; Strandberg, Bo; Eriksson, Axel; Bohgard, Mats; Bergemalm-Rynell, Kerstin; Gudmundsson, Anders

    2014-04-01

    Several diesel exhaust (DE) characteristics, comprising both particle and gas phase, recognized as important when linking with health effects, are not reported in human chamber exposure studies. In order to understand effects of DE on humans there is a need for better characterization of DE when performing exposure studies. The aim of this study was to determine and quantify detailed DE characteristics during human chamber exposure. Additionally to compare to reported DE properties in conducted human exposures. A wide battery of particle and gas phase measurement techniques have been used to provide detailed DE characteristics including the DE particles (DEP) surface area, fraction and dose deposited in the lungs, chemical composition of both particle and gas phase such as NO, NO2, CO, CO2, volatile organic compounds (including aldehydes, benzene, toluene) and polycyclic aromatic hydrocarbons (PAHs). Eyes, nose and throat irritation effects were determined. Exposure conditions with PM1 (<1 μm) mass concentration 280 μg m-3, number concentration 4 × 105 cm-3 and elemental to total carbon fraction of 82% were generated from a diesel vehicle at idling. When estimating the lung deposited dose it was found that using the size dependent effective density (in contrast to assuming unity density) reduced the estimated respiratory dose by 132% by mass. Accounting for agglomerated structure of DEP prevented underestimation of lung deposited dose by surface area by 37% in comparison to assuming spherical particles. Comparison of DE characteristics reported in conducted chamber exposures showed that DE properties vary to a great extent under the same DEP mass concentration and engine load. This highlights the need for detailed and standardized approach for measuring and reporting of DE properties. Eyes irritation effects, most probably caused by aldehydes in the gas phase, as well as nose irritation were observed at exposure levels below current occupational exposure limit

  16. Generation and characterization of gasoline engine exhaust inhalation exposure atmospheres.

    PubMed

    McDonald, Jacob D; Barr, Edward B; White, Richard K; Kracko, Dean; Chow, Judith C; Zielinska, Barbara; Grosjean, Eric

    2008-10-01

    Exposure atmospheres for a rodent inhalation toxicology study were generated from the exhaust of a 4.3-L gasoline engine coupled to a dynamometer and operated on an adapted California Unified Driving Cycle. Exposure levels were maintained at three different dilution rates. One chamber at the lowest dilution had particles removed by filtration. Each exposure atmosphere was characterized for particle mass, particle number, particle size distribution, and detailed chemical speciation. The majority of the mass in the exposure atmospheres was gaseous carbon monoxide, nitrogen oxides, and volatile organics, with small amounts of particle-bound carbon/ions and metals. The atmospheres varied according to the cycle, with the largest spikes in volatile organic and inorganic species shown during the "cold start" portion of the cycle. Ammonia present from the exhaust and rodents interacted with the gasoline exhaust to form secondary inorganic particles, and an increase in exhaust resulted in higher proportions of secondary inorganics as a portion of the total particle mass. Particle size had a median of 10-20 nm by number and approximately 150 nm by mass. Volatile organics matched the composition of the fuel, with large proportions of aliphatic and aromatic hydrocarbons coupled to low amounts of oxygenated organics. A new measurement technique revealed organics reacting with nitrogen oxides have likely resulted in measurement bias in previous studies of combustion emissions. Identified and measured particle organic species accounted for about 10% of total organic particle mass and were mostly aliphatic acids and polycyclic aromatic hydrocarbons. PMID:18951232

  17. Particle exposures and infections.

    PubMed

    Ghio, A J

    2014-06-01

    Particle exposures increase the risk for human infections. Particles can deposit in the nose, pharynx, larynx, trachea, bronchi, and distal lung and, accordingly, the respiratory tract is the system most frequently infected after such exposure; however, meningitis also occurs. Cigarette smoking, burning of biomass, dust storms, mining, agricultural work, environmental tobacco smoke (ETS), wood stoves, traffic-related emissions, gas stoves, and ambient air pollution are all particle-related exposures associated with an increased risk for respiratory infections. In addition, cigarette smoking, burning of biomass, dust storms, mining, and ETS can result in an elevated risk for tuberculosis, atypical mycobacterial infections, and meningitis. One of the mechanisms for particle-related infections includes an accumulation of iron by surface functional groups of particulate matter (PM). Since elevations in metal availability are common to every particle exposure, all PM potentially contributes to these infections. Therefore, exposures to wood stove emissions, diesel exhaust, and air pollution particles are predicted to increase the incidence and prevalence of tuberculosis, atypical mycobacterial infections, and meningitis, albeit these elevations are likely to be small and detectable only in large population studies. Since iron accumulation correlates with the presence of surface functional groups and dependent metal coordination by the PM, the risk for infection continues as long as the particle is retained. Subsequently, it is expected that the cessation of exposure will diminish, but not totally reverse, the elevated risk for infection. PMID:24488331

  18. Diesel exhaust particles and airway inflammation

    EPA Science Inventory

    Purpose of review. Epidemiologic investigation has associated traffic-related air pollution with adverse human health outcomes. The capacity ofdiesel exhaust particles (DEP), a major emission source air pollution particle, to initiate an airway inflammation has subsequently been ...

  19. Combined Inhaled Diesel Exhaust Particles and Allergen Exposure Alter Methylation of T Helper Genes and IgE Production In Vivo

    PubMed Central

    Liu, Jinming; Ballaney, Manisha; Al-alem, Umaima; Quan, Chunli; Jin, Ximei; Perera, Frederica; Chen, Lung-Chi; Miller, Rachel L.

    2008-01-01

    Changes in methylation of CpG sites at the interleukin (IL)-4 and interferon (IFN)-γ promoters are associated with T helper (Th) 2 polarization in vitro. No previous studies have examined whether air pollution or allergen exposure alters methylation of these two genes in vivo. We hypothesized that diesel exhaust particles (DEP) would induce hypermethylation of the IFN-γ promoter and hypomethylation of IL-4 in CD4+ T cells among mice sensitized to the fungus allergen Aspergillus fumigatus.We also hypothesized that DEP-induced methylation changes would affect immunoglobulin (Ig) E regulation. BALB/c mice were exposed to a 3-week course of inhaled DEP exposure while undergoing intranasal sensitization to A. fumigatus. Purified DNA from splenic CD4+ cells underwent bisulfite treatment, PCR amplification, and pyrosequencing. Sera IgE levels were compared with methylation levels at several CpG sites in the IL-4 and IFN-γ promoter. Total IgE production was increased following intranasal sensitization A. fumigatus. IgE production was augmented further following combined exposure to A. fumigatus and DEP exposure. Inhaled DEP exposure and intranasal A. fumigatus induced hypermethylation at CpG−45, CpG−53, CpG−205 sites of the IFN-γ promoter and hypomethylation at CpG−408 of the IL-4 promoter. Altered methylation of promoters of both genes was correlated significantly with changes in IgE levels. This study is the first to demonstrate that inhaled environmental exposures influence methylation of Th genes in vivo, supporting a new paradigm in asthma pathogenesis. PMID:18042818

  20. Power and particle exhaust in tokamaks

    SciTech Connect

    Stambaugh, R.D.

    1998-01-01

    The status of power and particle exhaust research in tokamaks is reviewed in the light of ITER requirements. There is a sound basis for ITER`s nominal design positions; important directions for further research are identified.

  1. Exposure of brown Norway rats to diesel exhaust particles prior to ovalbumin (OVA) sensitization elicits IgE adjuvant activity but attenuates OVA-induced airway inflammation.

    PubMed

    Dong, Caroline C; Yin, Xuejun J; Ma, Jane Y C; Millecchia, Lyndell; Barger, Mark W; Roberts, Jenny R; Zhang, Xing-Dong; Antonini, James M; Ma, Joseph K H

    2005-11-01

    Exposure to diesel exhaust particles (DEP) during the sensitization process has been shown to increase antigen-specific IgE production and aggravate allergic airway inflammation in human and animal models. In this study, we evaluated the effect of short-term DEP exposure on ovalbumin (OVA)-mediated responses using a post-sensitization model. Brown Norway rats were first exposed to filtered air or DEP (20.6 +/- 2.7 mg/m3) for 4 h/day for five consecutive days. One day after the final air or DEP exposure (day 1), rats were sensitized with aerosolized OVA (40.5 +/- 6.3 mg/m3), and then again on days 8 and 15, challenged with OVA on day 29, and sacrificed on days 9 or 30, 24 h after the second OVA exposure or the final OVA challenge, respectively. Control animals received aerosolized saline instead of OVA. DEP were shown to elicit an adjuvant effect on the production of antigen-specific IgE and IgG on day 30. At both time points, no significant airway inflammatory responses and lung injury were found for DEP exposure alone. However, the OVA-induced inflammatory cell infiltration, acellular lactate dehydrogenase activity and albumin content in bronchoalveolar lavage (BAL) fluid, and numbers of T cells and their CD4+ and CD8+ subsets in lung-draining lymph nodes were markedly reduced by DEP on day 30 compared with the air-plus-OVA exposure group. The OVA-induced nitric oxide (NO) in the BAL fluid and production of NO, interleukin (IL)-10, and IL-12 by alveolar macrophages (AM) were also significantly lowered by DEP on day 30 as well as day 9. DEP or OVA alone decreased intracellular glutathione (GSH) in AM and lymphocytes on days 9 and 30. The combined DEP and OVA exposure resulted in further depletion of GSH in both cell types. These results show that short-term DEP exposure prior to sensitization had a delayed effect on enhancement of the sensitization in terms of allergen-specific IgE and IgG production, but caused an attenuation of the allergen-induced airway

  2. Exposure to Diesel Exhaust Particle Extracts (DEPe) Impairs Some Polarization Markers and Functions of Human Macrophages through Activation of AhR and Nrf2

    PubMed Central

    Jaguin, Marie; Fardel, Olivier; Lecureur, Valérie

    2015-01-01

    Macrophages (MΦ), well-known to play an important role in immune response, also respond to environmental toxic chemicals such as diesel exhaust particles (DEP). Potential effects of DEPs towards MΦ polarization, a key hall-mark of MΦ physiology, remain however poorly documented. This study was therefore designed to evaluate the effects of a reference DEP extract (DEPe) on human MΦ polarization. Human blood monocytes-derived MΦ were incubated with IFNγ+LPS or IL-4 to obtain M1 and M2 subtypes, respectively; a 24 h exposure of polarizing MΦ to 10 μg/ml DEPe was found to impair expression of some macrophagic M1 and M2 markers, without however overall inhibition of M1 and M2 polarization processes. Notably, DEPe treatment increased the secretion of the M1 marker IL-8 and the M2 marker IL-10 in both MΦ subtypes, whereas it reduced lipopolysaccharide-induced IL-6 and IL-12p40 secretion in M1 MΦ. In M2 MΦ, DEPe exposure led to a reduction of CD200R expression and of CCL17, CCL18 and CCL22 secretion, associated with a lower chemotaxis of CCR4-positive cells. DEPe activated the Nrf2 and AhR pathways and induced expression of their reference target genes such as Hmox-1 and cytochrome P-4501B1 in M1 and M2 MΦ. Nrf2 or AhR silencing through RNA interference prevented DEPe-related down-regulation of IL-6. AhR silencing also inhibited the down-secretion of IL-12p40 and CCL18 in M1- and M2-DEPe-exposed MΦ, respectively. DEPs are therefore likely to alter expression of some M1 and M2 markers in an AhR- and Nrf2-dependent manner; such regulations may contribute to deleterious immune effects of atmospheric DEP. PMID:25710172

  3. Real-time and integrated measurement of potential human exposure to particle-bound polycyclic aromatic hydrocarbons (PAHs) from aircraft exhaust.

    PubMed Central

    Childers, J W; Witherspoon, C L; Smith, L B; Pleil, J D

    2000-01-01

    We used real-time monitors and low-volume air samplers to measure the potential human exposure to airborne polycyclic aromatic hydrocarbon (PAH) concentrations during various flight-related and ground-support activities of C-130H aircraft at an Air National Guard base. We used three types of photoelectric aerosol sensors (PASs) to measure real-time concentrations of particle-bound PAHs in a break room, downwind from a C-130H aircraft during a four-engine run-up test, in a maintenance hangar, in a C-130H aircraft cargo bay during cargo-drop training, downwind from aerospace ground equipment (AGE), and in a C-130H aircraft cargo bay during engine running on/off (ERO) loading and backup exercises. Two low-volume air samplers were collocated with the real-time monitors for all monitoring events except those in the break room and during in-flight activities. Total PAH concentrations in the integrated-air samples followed a general trend: downwind from two AGE units > ERO-loading exercise > four-engine run-up test > maintenance hangar during taxi and takeoff > background measurements in maintenance hangar. Each PAH profile was dominated by naphthalene, the alkyl-substituted naphthalenes, and other PAHs expected to be in the vapor phase. We also found particle-bound PAHs, such as fluoranthene, pyrene, and benzo[a]pyrene in some of the sample extracts. During flight-related exercises, total PAH concentrations in the integrated-air samples were 10-25 times higher than those commonly found in ambient air. Real-time monitor mean responses generally followed the integrated-air sample trends. These monitors provided a semiquantitative temporal profile of ambient PAH concentrations and showed that PAH concentrations can fluctuate rapidly from a baseline level < 20 to > 4,000 ng/m(3) during flight-related activities. Small handheld models of the PAS monitors exhibited potential for assessing incidental personal exposure to particle-bound PAHs in engine exhaust and for serving as

  4. Real-time and integrated measurement of potential human exposure to particle-bound polycyclic aromatic hydrocarbons (PAHs) from aircraft exhaust.

    PubMed

    Childers, J W; Witherspoon, C L; Smith, L B; Pleil, J D

    2000-09-01

    We used real-time monitors and low-volume air samplers to measure the potential human exposure to airborne polycyclic aromatic hydrocarbon (PAH) concentrations during various flight-related and ground-support activities of C-130H aircraft at an Air National Guard base. We used three types of photoelectric aerosol sensors (PASs) to measure real-time concentrations of particle-bound PAHs in a break room, downwind from a C-130H aircraft during a four-engine run-up test, in a maintenance hangar, in a C-130H aircraft cargo bay during cargo-drop training, downwind from aerospace ground equipment (AGE), and in a C-130H aircraft cargo bay during engine running on/off (ERO) loading and backup exercises. Two low-volume air samplers were collocated with the real-time monitors for all monitoring events except those in the break room and during in-flight activities. Total PAH concentrations in the integrated-air samples followed a general trend: downwind from two AGE units > ERO-loading exercise > four-engine run-up test > maintenance hangar during taxi and takeoff > background measurements in maintenance hangar. Each PAH profile was dominated by naphthalene, the alkyl-substituted naphthalenes, and other PAHs expected to be in the vapor phase. We also found particle-bound PAHs, such as fluoranthene, pyrene, and benzo[a]pyrene in some of the sample extracts. During flight-related exercises, total PAH concentrations in the integrated-air samples were 10-25 times higher than those commonly found in ambient air. Real-time monitor mean responses generally followed the integrated-air sample trends. These monitors provided a semiquantitative temporal profile of ambient PAH concentrations and showed that PAH concentrations can fluctuate rapidly from a baseline level < 20 to > 4,000 ng/m(3) during flight-related activities. Small handheld models of the PAS monitors exhibited potential for assessing incidental personal exposure to particle-bound PAHs in engine exhaust and for serving as

  5. Vascular and Cardiac Impairments in Rats Inhaling Ozone and Diesel Exhaust Particles

    EPA Science Inventory

    Background -Mechanisms of cardiovascular injuries from exposure to gas and particulate air pollutants are unknown. Objective -We hypothesized that episodic exposure of rats to ozone or diesel exhaust particles (DEP) will cause differential cardiovascular impairments, which will b...

  6. Estimation of the diesel exhaust exposures of railroad workers. II. National and historical exposures

    SciTech Connect

    Woskie, S.R.; Smith, T.J.; Hammond, S.K.; Schenker, M.B.; Garshick, E.; Speizer, F.E.

    1988-01-01

    The diesel exhaust exposures of railroad workers in thirteen job groups from four railroads in the United States were used to estimate U.S. national average exposures with a linear statistical model which accounts for the significant variability in exposure caused by climate, the differences among railroads and the uneven distribution of railroad workers across climatic regions. Personal measurements of respirable particulate matter, adjusted to remove the contribution of cigarette smoke particles, were used as a marker for diesel exhaust. The estimated national means of adjusted respirable particulate matter (ARP) averaged 10 micrograms/m3 lower than the simple means for each job group, reflecting the climatic differences between the northern railroads studied and the distribution of railroad workers nationally. Limited historical records, including some industrial hygiene data, were used to evaluate past diesel exhaust exposures, which were estimated to be approximately constant from the 1950's to 1983.

  7. Particle exposures and infections

    EPA Science Inventory

    Particle exposures increase the risk for human infections. Particles can deposit in the nose, pharynx, larynx, trachea, bronchi, and distal lung and, accordingly, the respiratory tract is the system most frequently infected after such exposure; however, meningitis also occurs. Ci...

  8. DNA damage and cytotoxicity in type II lung epithelial (A549) cell cultures after exposure to diesel exhaust and urban street particles

    PubMed Central

    Danielsen, Pernille Høgh; Loft, Steffen; Møller, Peter

    2008-01-01

    Background Exposure to air pollution particles has been acknowledged to be associated with excess generation of oxidative damage to DNA in experimental model systems and humans. The use of standard reference material (SRM), such as SRM1650 and SRM2975, is advantageous because experiments can be reproduced independently, but exposure to such samples may not mimic the effects observed after exposure to authentic air pollution particles. This study was designed to compare the DNA oxidizing effects of authentic street particles with SRM1650 and SRM2975. The authentic street particles were collected at a traffic intensive road in Copenhagen, Denmark. Results All of the particles generated strand breaks and oxidized purines in A549 lung epithelial cells in a dose-dependent manner and there were no overt differences in their potency. The exposures also yielded dose-dependent increase of cytotoxicity (as lactate dehydrogenase release) and reduced colony forming ability with slightly stronger cytotoxicity of SRM1650 than of the other particles. In contrast, only the authentic street particles were able to generate 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodG) in calf thymus DNA, which might be due to the much higher level of transition metals. Conclusion Authentic street particles and SRMs differ in their ability to oxidize DNA in a cell-free environment, whereas cell culture experiments indicate that the particle preparations elicit a similar alteration of the level of DNA damage and small differences in cytotoxicity. Although it cannot be ruled out that SRMs and authentic street particles might elicit different effects in animal experimental models, this study indicates that on the cellular level, SRM1650 and SRM2975 are suitable surrogate samples for the study of authentic street particles. PMID:18397523

  9. Pulmonary and cardiovascular effects of traffic-related particulate matter: 4-week exposure of rats to roadside and diesel engine exhaust particles.

    PubMed

    Gerlofs-Nijland, Miriam E; Totlandsdal, Annike I; Kilinç, Evren; Boere, A John F; Fokkens, Paul H B; Leseman, Daan L A C; Sioutas, Constantinos; Schwarze, Per E; Spronk, Henri M; Hadoke, Patrick W F; Miller, Mark R; Cassee, Flemming R

    2010-12-01

    Traffic-related particulate matter (PM) may play an important role in the development of adverse health effects, as documented extensively in acute toxicity studies. However, rather little is known about the impacts of prolonged exposure to PM. We hypothesized that long-term exposure to PM from traffic adversely affects the pulmonary and cardiovascular system through exacerbation of an inflammatory response. To examine this hypothesis, Fisher F344 rats, with a mild pulmonary inflammation at the onset of exposure, were exposed for 4 weeks, 5 days/week for 6 h a day to: (a) diluted diesel engine exhaust (PM(DEE)), or: (b) near roadside PM (PM(2.5)). Ultrafine particulates, which are largely present in diesel soot, may enter the systemic circulation and directly or indirectly trigger cardiovascular effects. Hence, we assessed the effects of traffic-related PM on pulmonary inflammation and activity of procoagulants, vascular function in arteries, and cytokine levels in the heart 24 h after termination of the exposures. No major adverse health effects of prolonged exposure to traffic-related PM were detected. However, some systemic effects due to PM(DEE) exposure occurred including decreased numbers of white blood cells and reduced von Willebrand factor protein in the circulation. In addition, lung tissue factor activity is reduced in conjunction with reduced lung tissue thrombin generation. To what extent these alterations contribute to thrombotic effects and vascular diseases remains to be established. In conclusion, prolonged exposure to traffic-related PM in healthy animals may not be detrimental due to various biological adaptive response mechanisms. PMID:21126152

  10. DIESEL EXHAUST PARTICLES INDUCE ABERRANT ALVEOLAR EPITHELIAL DIRECTED CELL MOVEMENT BY DISRUPTION OF POLARITY MECHANISMS

    EPA Science Inventory

    Disruption of the respiratory epithelium contributes to the progression of a variety of respiratory diseases that are aggravated by exposure to air pollutants, specifically traffic-based pollutants such as diesel exhaust particles (DEP). Recognizing that lung repair following inj...

  11. Exhaust particle removing system for an engine

    SciTech Connect

    Shinzawa, M.

    1986-12-23

    A method is described comprising the steps of: (a) measuring degree of clogging of a filter which traps particles suspended in exhaust gas emitted from an engine; (b) indicating when the measured degree of clogging of the filter is equal to or greater than a first reference level; (c) burning off the particles deposited on the filter when the measured degree of clogging of the filter is equal to or greater than the first reference level and when a manual switch is in a preset position; and (d) burning off the particles deposited on the filter independent of whether or not the manual switch is in the preset position when the measured degree of clogging of the filter is equal to or greater than a second reference level greater than the first reference level.

  12. Measuring soot particles from automotive exhaust emissions

    NASA Astrophysics Data System (ADS)

    Andres, Hanspeter; Lüönd, Felix; Schlatter, Jürg; Auderset, Kevin; Jordan-Gerkens, Anke; Nowak, Andreas; Ebert, Volker; Buhr, Egbert; Klein, Tobias; Tuch, Thomas; Wiedensohler, Alfred; Mamakos, Athanasios; Riccobono, Francesco; Discher, Kai; Högström, Richard; Yli-Ojanperä, Jaakko; Quincey, Paul

    2014-08-01

    The European Metrology Research Programme participating countries and the European Union jointly fund a three year project to address the need of the automotive industry for a metrological sound base for exhaust measurements. The collaborative work on particle emissions involves five European National Metrology Institutes, the Tampere University of Technology, the Joint Research Centre for Energy and Transport and the Leibniz Institute for Tropospheric Research. On one hand, a particle number and size standard for soot particles is aimed for. Eventually this will allow the partners to provide accurate and comparable calibrations of measurement instruments for the type approval of Euro 5b and Euro 6 vehicles. Calibration aerosols of combustion particles, silver and graphite proof partially suitable. Yet, a consensus choice together with instrument manufactures is pending as the aerosol choice considerably affects the number concentration measurement. Furthermore, the consortium issued consistent requirements for novel measuring instruments foreseen to replace today's opacimeters in regulatory periodic emission controls of soot and compared them with European legislative requirements. Four partners are conducting a metrological validation of prototype measurement instruments. The novel instruments base on light scattering, electrical, ionisation chamber and diffusion charging sensors and will be tested at low and high particle concentrations. Results shall allow manufacturers to further improve their instruments to comply with legal requirements.

  13. GASOLINE VEHICLE EXHAUST PARTICLE SAMPLING STUDY

    SciTech Connect

    Kittelson, D; Watts, W; Johnson, J; Zarling, D Schauer,J Kasper, K; Baltensperger, U; Burtscher, H

    2003-08-24

    The University of Minnesota collaborated with the Paul Scherrer Institute, the University of Wisconsin (UWI) and Ricardo, Inc to physically and chemically characterize the exhaust plume from recruited gasoline spark ignition (SI) vehicles. The project objectives were: (1) Measure representative particle size distributions from a set of on-road SI vehicles and compare these data to similar data collected on a small subset of light-duty gasoline vehicles tested on a chassis dynamometer with a dilution tunnel using the Unified Drive Cycle, at both room temperature (cold start) and 0 C (cold-cold start). (2) Compare data collected from SI vehicles to similar data collected from Diesel engines during the Coordinating Research Council E-43 project. (3) Characterize on-road aerosol during mixed midweek traffic and Sunday midday periods and determine fleet-specific emission rates. (4) Characterize bulk- and size-segregated chemical composition of the particulate matter (PM) emitted in the exhaust from the gasoline vehicles. Particle number concentrations and size distributions are strongly influenced by dilution and sampling conditions. Laboratory methods were evaluated to dilute SI exhaust in a way that would produce size distributions that were similar to those measured during laboratory experiments. Size fractionated samples were collected for chemical analysis using a nano-microorifice uniform deposit impactor (nano-MOUDI). In addition, bulk samples were collected and analyzed. A mixture of low, mid and high mileage vehicles were recruited for testing during the study. Under steady highway cruise conditions a significant particle signature above background was not measured, but during hard accelerations number size distributions for the test fleet were similar to modern heavy-duty Diesel vehicles. Number emissions were much higher at high speed and during cold-cold starts. Fuel specific number emissions range from 1012 to 3 x 1016 particles/kg fuel. A simple

  14. Impaired vascular function after exposure to diesel exhaust generated at urban transient running conditions

    PubMed Central

    2010-01-01

    Background Traffic emissions including diesel engine exhaust are associated with increased respiratory and cardiovascular morbidity and mortality. Controlled human exposure studies have demonstrated impaired vascular function after inhalation of exhaust generated by a diesel engine under idling conditions. Objectives To assess the vascular and fibrinolytic effects of exposure to diesel exhaust generated during urban-cycle running conditions that mimic ambient 'real-world' exposures. Methods In a randomised double-blind crossover study, eighteen healthy male volunteers were exposed to diesel exhaust (approximately 250 μg/m3) or filtered air for one hour during intermittent exercise. Diesel exhaust was generated during the urban part of the standardized European Transient Cycle. Six hours post-exposure, vascular vasomotor and fibrinolytic function was assessed during venous occlusion plethysmography with intra-arterial agonist infusions. Measurements and Main Results Forearm blood flow increased in a dose-dependent manner with both endothelial-dependent (acetylcholine and bradykinin) and endothelial-independent (sodium nitroprusside and verapamil) vasodilators. Diesel exhaust exposure attenuated the vasodilatation to acetylcholine (P < 0.001), bradykinin (P < 0.05), sodium nitroprusside (P < 0.05) and verapamil (P < 0.001). In addition, the net release of tissue plasminogen activator during bradykinin infusion was impaired following diesel exhaust exposure (P < 0.05). Conclusion Exposure to diesel exhaust generated under transient running conditions, as a relevant model of urban air pollution, impairs vasomotor function and endogenous fibrinolysis in a similar way as exposure to diesel exhaust generated at idling. This indicates that adverse vascular effects of diesel exhaust inhalation occur over different running conditions with varying exhaust composition and concentrations as well as physicochemical particle properties. Importantly, exposure to diesel exhaust

  15. Involvement of MEK-ERK1-2 pathway in the anti-oxidant response in C6 glioma cells after diesel exhaust particles exposure.

    PubMed

    Farina, Francesca; Milani, Chiara; Botto, Laura; Lonati, Elena; Bulbarelli, Alessandra; Palestini, Paola

    2016-05-27

    Ultrafine particles translocate to the central nervous system and activate oxidative stress-related pathways. The transcription factor Nrf2 activation by ERK1-2 has been suggested as a key regulator of cellular response to oxidative stress. C6 glioma cells have been treated with different doses of diesel exhaust particles (25μg/ml, DEP25, and 50μg/ml, DEP50), for different times. Cells have been screened for oxidative stress and inflammatory markers, and for the activation of the MEK-ERK1-2 pathway. The same markers have been examined after inhibition of MEK, the kinase upstream to ERK1-2. 3h and 24h of DEP25 and DEP50 induced a significant increase in HO-1 levels. After 24h, DEP25 and DEP50 induced an increase in HO-1 and Cyp1b1 levels, while increase in OGG1 level was observed only with DEP25. After 5h of treatment with DEP25, ERK1-2 resulted phosphorylated, concomitantly with a significant increase in HO-1 levels, no changes in iNOS levels, and decreased levels of anti-oxidant enzymes. After treatment with MEK inhibitor U0126, ERK1-2 showed no activation, with a consequent decrease in Nrf2, no increase in HO-1 and a significant increase of iNOS. MEK inhibitor is able to deplete anti-oxidant enzymes. In conclusion, the MEK-ERK1-2 pathway is involved in regulating the anti-oxidant strategies to compensate the oxidative status induced by DEP treatment. PMID:27091075

  16. Exposure to diesel exhaust linked to lung cancer in miners

    Cancer.gov

    In a study of non-metal miners in the United States, federal government scientists reported that heavy exposure to diesel exhaust increased risk of death from lung cancer. The research, all part of the Diesel Exhaust in Miners Study, was designed to evalu

  17. NASAL RESPONSES OF ASTHMATIC AND NON-ASTHMATIC VOLUNTEERS TO DIESEL EXHAUST PARTICLES

    EPA Science Inventory

    Asthma rates have been increasing world-wide, and exposure to diesel exhaust particles (DEP) may be implicated in this increase. Additionally DEP may also play a role in the increased morbidity and mortality associated with ambient airborne PM exposure. Two types of nasal respons...

  18. BEHAVIORAL ALTERATIONS DUE TO DIESEL EXHAUST EXPOSURE

    EPA Science Inventory

    Several experiments examining the effects of diesel exhaust on the behavior of rats are reported. Animals were exposed either as adults or neonates. The spontaneous locomotor activity (SLA), measured in standard running wheel cages, of adult rats exposed for 8 h/day, 7 days/week ...

  19. Occupational exposure to chain saw exhausts in logging operations

    SciTech Connect

    Nilsson, C.A.; Lindahl, R.; Norstroem, A.

    1987-02-01

    The composition of exhaust emissions from two-stroke chain saw engines was studied. The emissions of exhaust were sampled and analyzed under controlled laboratory experiments. The compounds sampled were those considered primarily responsible for acute health effects - hydrocarbons, aldehydes, nitrogen oxides and carbon monoxide. Exposure to tetramethyllead, dibromoethane and polycyclic aromatic hydrocarbons also was monitored. The results revealed no significant differences in the exhaust emissions from seven different chain saws. Heavily worn-out chain saws do not emit increased amounts of exhaust. A lean fuel-air mixture increases the emission of aldehydes and nitrogen oxides, whereas a rich mixture increases emission of carbon monoxide and hydrocarbons. Based on these new data on the composition of two-stroke chain saw exhaust emissions, operator exposure to chain saw exhaust was evaluated under various logging situations. Exposure measurements revealed no difference in average levels of exposure between logging in the presence or in the absence of snow. The felling operating, however, results in high exposure levels of short duration - especially when the operation is performed while there is deep snow on the ground. This is judged to be the main cause of the discomfort experienced by loggers. Average exposure levels for loggers engaged only in felling are twice those for cutters who also perform limbing, bucking and manual skidding of the timber, since these latter operations involve considerably lower exposure. Typical average levels of exposure are as follows: hydrocarbons, 20 mg/m/sup 3/; formaldehyde, 0.1 mg/m/sup 3/; and carbon monoxide, 20 mg/m/sup 3/.

  20. Predictive models for deposition of inhaled diesel exhaust particles in humans and laboratory species

    SciTech Connect

    Yu, C.P.; Xu, G.B. )

    1987-01-01

    Mathematical and computer models of the respiratory tracts of human beings and of laboratory animals (rats, hamsters, guinea pigs) were used to estimate the deposition patterns of inhaled diesel exhaust particles from automobile emissions. Our goal was to be able to predict the relation between exposure to diesel exhaust particles and the deposition of these particles in the lungs of humans of various ages. Diesel exhaust particles are aggregates with a mass median aerodynamic diameter of approximately 0.2 micron. Their actual size depends on the conditions under which they are generated. Using an appropriate particle model, we derived mathematical expressions that describe the effects of diffusion, sedimentation, impaction, and interception on the deposition of these particles. Because of their small size, we found that most diesel exhaust particles deposited through diffusion, and that the role of the other mechanisms was minor. Anatomical models of the human lung from birth to adulthood, as well as models of the lungs of laboratory species were formulated mathematically using available morphometric data. We used these lung models, together with the corresponding ventilation conditions of each species, to calculate deposition of diesel exhaust particles in the lungs. Under normal breathing conditions, we calculated that 7 to 13 percent (depending on particle size) of inhaled diesel exhaust particles deposit in the alveolar region of the adult human lung. Although the breathing mode (nose or mouth breathing) did not appear to affect alveolar deposition, increasing the minute ventilation increased alveolar deposition significantly. The calculated deposition patterns for diesel exhaust particles in younger humans (under age 25) were similar.

  1. DIFFERENTIAL CARDIAC SUSCEPTIBILITY OF WISTAR KYOTO (WKY) AND SPONTANEOUSLY HYPERTENSIVE RATS (SHR) TO DIESEL EXHAUST EXPOSURE

    EPA Science Inventory

    Exposure to diesel exhaust particles (DEP) is linked to increases in cardiovascular effects. This is enhanced in individuals with pre-existing disease. Animal models of cardiovascular disease are used to study this susceptibility. The heart is rich in mitochondria, which produce ...

  2. Physicochemical characterisation of combustion particles from vehicle exhaust and residential wood smoke

    PubMed Central

    Kocbach, Anette; Li, Yanjun; Yttri, Karl E; Cassee, Flemming R; Schwarze, Per E; Namork, Ellen

    2006-01-01

    Background Exposure to ambient particulate matter has been associated with a number of adverse health effects. Particle characteristics such as size, surface area and chemistry seem to influence the negative effects of particles. In this study, combustion particles from vehicle exhaust and wood smoke, currently used in biological experiments, were analysed with respect to microstructure and chemistry. Methods Vehicle exhaust particles were collected in a road tunnel during two seasons, with and without use of studded tires, whereas wood smoke was collected from a stove with single-stage combustion. Additionally, a reference diesel sample (SRM 2975) was analysed. The samples were characterised using transmission electron microscopy techniques (TEM/HRTEM, EELS and SAED). Furthermore, the elemental and organic carbon fractions were quantified using thermal optical transmission analysis and the content of selected PAHs was determined by gas chromatography-mass spectrometry. Results Carbon aggregates, consisting of tens to thousands of spherical primary particles, were the only combustion particles identified in all samples using TEM. The tunnel samples also contained mineral particles originating from road abrasion. The geometric diameters of primary carbon particles from vehicle exhaust were found to be significantly smaller (24 ± 6 nm) than for wood smoke (31 ± 7 nm). Furthermore, HRTEM showed that primary particles from both sources exhibited a turbostratic microstructure, consisting of concentric carbon layers surrounding several nuclei in vehicle exhaust or a single nucleus in wood smoke. However, no differences were detected in the graphitic character of primary particles from the two sources using SAED and EELS. The total PAH content was higher for combustion particles from wood smoke as compared to vehicle exhaust, whereas no source difference was found for the ratio of organic to total carbon. Conclusion Combustion particles from vehicle exhaust and

  3. INHIBITION OF TYROSINE PHOSPHATASE ACTIVITY INITIATES RECEPTOR SIGNALING IN AIRWAY EPITHELIAL CELLS EXPOSED TO DIESEL EXHAUST PARTICLES

    EPA Science Inventory

    Exposure to particulate matter is associated with increased cardiopulmonary morbidity and mortality. Diesel exhaust particles (DEP) are a major component of PM in urban areas and may contribute to PM toxicity through a mechanism involving pulmonary inflammation. Expression of inf...

  4. Concordance in Genomic Changes Between Mouse Lungs and Human Airway Epithelial Cells Exposed to Diesel Exhaust Particles

    EPA Science Inventory

    Human and animal toxicity studies have shown that exposure to diesel exhaust particles (DEP) or their constituents affect multiple biological processes including immune and inflammatory pathways, mutagenesis and in some cases carcinogenesis. This study compared genomic changes by...

  5. Are urinary PAHs biomarkers of controlled exposure to diesel exhaust?

    PubMed Central

    Lu, Sixin S.; Sobus, Jon R.; Sallsten, Gerd; Albin, Maria; Pleil, Joachim D.; Gudmundsson, Anders; Madden, Michael C.; Strandberg, Bo; Wierzbicka, Aneta; Rappaport, Stephen M.

    2016-01-01

    Urinary polycyclic aromatic hydrocarbons (PAHs) were evaluated as possible biomarkers of exposure to diesel exhaust (DE) in two controlled-chamber studies. We report levels of 14 PAHs from 28 subjects in urine that were collected before, immediately after and the morning after exposure. Using linear mixed-effects models, we tested for effects of DE exposure and several covariates (time, age, gender and urinary creatinine) on urinary PAH levels. DE exposures did not significantly alter urinary PAH levels. We conclude that urinary PAHs are not promising biomarkers of short-term exposures to DE in the range of 106–276 μg/m3. PMID:24754404

  6. Endocrine-disrupting activity of chemicals in diesel exhaust and diesel exhaust particles.

    PubMed

    Takeda, Ken; Tsukue, Naomi; Yoshida, Seiichi

    2004-01-01

    Diesel exhaust (DE) is known as the main cause of air pollution. DE is a complex mixture of particulate and vapor-phase compounds. The soluble organic fraction of the particulate materials in DE contains thousands of compounds including a variety of polycyclic aromatic hydrocarbons and heavy metals. To clarify the endocrine-disrupting activities of DE, we have reviewed the reports about the effects of DE on the reproductive and brain-nervous systems, and the endocrine-disrupting action of diesel exhaust particles (DEP). In utero exposure to low levels (0.1 mg DEP/m3) of DE from day 2 postcoitum (p.c.) until day 13 p.c. reduced the expression level of Ad4BP/SF-1 mRNA and thereby might affect the development of gonads. Low levels of DE also reduced the expression of several genes known to play key roles in gonadal development, including an enzyme necessary for testosterone synthesis. Mature male rats exposed to DE during the fetal period showed an irreversible decrease in daily sperm production due to an insufficient number of Sertoli cells. DE exposure during the fetal period influenced the brain tissue in newborn mice. In the 3 mg DEP/m3 exposure group at 10 weeks of age, a significant reduction in performance was observed in the passive avoidance learning test in both male and female mice. In addition, the fetal exposure of mice to DE affected the emotional behaviors associated with the serotonergic and dopaminergic systems in the mouse brain. In toluidine blue-stained specimens from the DE-exposed group, edema around the vessels where fluorescent granular perithelial (FGP) cells exist and degenerated granules within the FGP cytoplasm were observed; similar findings were obtained by electron microscopic examination. DEP contain many substances that stimulate Ah receptors, such as the polycyclic aromatic hydrocarbon containing benzo[a]pyrene. DEP also contain substances with estrogenic, antiestrogenic and antiandrogenic activities. The neutral substance fraction of

  7. REAL-TIME AND INTEGRATED MEASUREMENT OF POTENTIAL HUMAN EXPOSURE TO PARTICLE-BOUND POLYCYCLIC AROMATIC HYDROCARBONS (PAHS) FROM AIRCRAFT EXHAUST

    EPA Science Inventory

    Real-time monitors and low-volume air samplers were used to measure the potential human exposure to airborne polycyclic aromatic hydrocarbon (PAH) concentrations during various flight-related and ground-support activities of C-130H aircraft at an Air National Guard base. Three...

  8. DIESEL EXHAUST PARTICLE-INDUCED EPITHELIAL TOXICITY IS MODULATED BY UV-IRRADIATION -- NCSU

    EPA Science Inventory

    Asthma is a chronic inflammatory disorder of the airways affecting nearly 20 million individuals in the U.S alone. Asthmatic symptoms can be exacerbated by environmental insults like exposure to particulate matter (PM). Diesel exhaust particles (DEP) account for a portion of PM...

  9. The Involvement of Superoxide and Nitric Oxide in Inflammation-Enhanced Diesel Exhaust Particle Cytotoxicity

    EPA Science Inventory

    Thirty-four million Americans have asthma, a chronic inflammatory lung disease. Although the mechanisms are unclear, epidemiologic studies show that exposure of asthmatics to air pollutants, like diesel exhaust particles (DEP), is more likely to result in adverse health effects....

  10. DIESEL EXHAUST PARTICLE-INDUCED EPITHELIAL TOXICITY IS MODULATED BY UV-IRRADIATION

    EPA Science Inventory

    Asthma is a chronic inflammatory disorder of the airways affecting nearly 20 million individuals in the U.S alone. Asthmatic symptoms can be exacerbated by environmental insults like exposure to particulate matter (PM). Diesel exhaust particles (DEP) account for a significant por...

  11. Toxicity of aged gasoline exhaust particles to normal and diseased airway epithelia.

    PubMed

    Künzi, Lisa; Krapf, Manuel; Daher, Nancy; Dommen, Josef; Jeannet, Natalie; Schneider, Sarah; Platt, Stephen; Slowik, Jay G; Baumlin, Nathalie; Salathe, Matthias; Prévôt, André S H; Kalberer, Markus; Strähl, Christof; Dümbgen, Lutz; Sioutas, Constantinos; Baltensperger, Urs; Geiser, Marianne

    2015-01-01

    Particulate matter (PM) pollution is a leading cause of premature death, particularly in those with pre-existing lung disease. A causative link between particle properties and adverse health effects remains unestablished mainly due to complex and variable physico-chemical PM parameters. Controlled laboratory experiments are required. Generating atmospherically realistic aerosols and performing cell-exposure studies at relevant particle-doses are challenging. Here we examine gasoline-exhaust particle toxicity from a Euro-5 passenger car in a uniquely realistic exposure scenario, combining a smog chamber simulating atmospheric ageing, an aerosol enrichment system varying particle number concentration independent of particle chemistry, and an aerosol deposition chamber physiologically delivering particles on air-liquid interface (ALI) cultures reproducing normal and susceptible health status. Gasoline-exhaust is an important PM source with largely unknown health effects. We investigated acute responses of fully-differentiated normal, distressed (antibiotics-treated) normal, and cystic fibrosis human bronchial epithelia (HBE), and a proliferating, single-cell type bronchial epithelial cell-line (BEAS-2B). We show that a single, short-term exposure to realistic doses of atmospherically-aged gasoline-exhaust particles impairs epithelial key-defence mechanisms, rendering it more vulnerable to subsequent hazards. We establish dose-response curves at realistic particle-concentration levels. Significant differences between cell models suggest the use of fully-differentiated HBE is most appropriate in future toxicity studies. PMID:26119831

  12. Toxicity of aged gasoline exhaust particles to normal and diseased airway epithelia

    PubMed Central

    Künzi, Lisa; Krapf, Manuel; Daher, Nancy; Dommen, Josef; Jeannet, Natalie; Schneider, Sarah; Platt, Stephen; Slowik, Jay G.; Baumlin, Nathalie; Salathe, Matthias; Prévôt, André S. H.; Kalberer, Markus; Strähl, Christof; Dümbgen, Lutz; Sioutas, Constantinos; Baltensperger, Urs; Geiser, Marianne

    2015-01-01

    Particulate matter (PM) pollution is a leading cause of premature death, particularly in those with pre-existing lung disease. A causative link between particle properties and adverse health effects remains unestablished mainly due to complex and variable physico-chemical PM parameters. Controlled laboratory experiments are required. Generating atmospherically realistic aerosols and performing cell-exposure studies at relevant particle-doses are challenging. Here we examine gasoline-exhaust particle toxicity from a Euro-5 passenger car in a uniquely realistic exposure scenario, combining a smog chamber simulating atmospheric ageing, an aerosol enrichment system varying particle number concentration independent of particle chemistry, and an aerosol deposition chamber physiologically delivering particles on air-liquid interface (ALI) cultures reproducing normal and susceptible health status. Gasoline-exhaust is an important PM source with largely unknown health effects. We investigated acute responses of fully-differentiated normal, distressed (antibiotics-treated) normal, and cystic fibrosis human bronchial epithelia (HBE), and a proliferating, single-cell type bronchial epithelial cell-line (BEAS-2B). We show that a single, short-term exposure to realistic doses of atmospherically-aged gasoline-exhaust particles impairs epithelial key-defence mechanisms, rendering it more vulnerable to subsequent hazards. We establish dose-response curves at realistic particle-concentration levels. Significant differences between cell models suggest the use of fully-differentiated HBE is most appropriate in future toxicity studies. PMID:26119831

  13. Toxicity of aged gasoline exhaust particles to normal and diseased airway epithelia

    NASA Astrophysics Data System (ADS)

    Künzi, Lisa; Krapf, Manuel; Daher, Nancy; Dommen, Josef; Jeannet, Natalie; Schneider, Sarah; Platt, Stephen; Slowik, Jay G.; Baumlin, Nathalie; Salathe, Matthias; Prévôt, André S. H.; Kalberer, Markus; Strähl, Christof; Dümbgen, Lutz; Sioutas, Constantinos; Baltensperger, Urs; Geiser, Marianne

    2015-06-01

    Particulate matter (PM) pollution is a leading cause of premature death, particularly in those with pre-existing lung disease. A causative link between particle properties and adverse health effects remains unestablished mainly due to complex and variable physico-chemical PM parameters. Controlled laboratory experiments are required. Generating atmospherically realistic aerosols and performing cell-exposure studies at relevant particle-doses are challenging. Here we examine gasoline-exhaust particle toxicity from a Euro-5 passenger car in a uniquely realistic exposure scenario, combining a smog chamber simulating atmospheric ageing, an aerosol enrichment system varying particle number concentration independent of particle chemistry, and an aerosol deposition chamber physiologically delivering particles on air-liquid interface (ALI) cultures reproducing normal and susceptible health status. Gasoline-exhaust is an important PM source with largely unknown health effects. We investigated acute responses of fully-differentiated normal, distressed (antibiotics-treated) normal, and cystic fibrosis human bronchial epithelia (HBE), and a proliferating, single-cell type bronchial epithelial cell-line (BEAS-2B). We show that a single, short-term exposure to realistic doses of atmospherically-aged gasoline-exhaust particles impairs epithelial key-defence mechanisms, rendering it more vulnerable to subsequent hazards. We establish dose-response curves at realistic particle-concentration levels. Significant differences between cell models suggest the use of fully-differentiated HBE is most appropriate in future toxicity studies.

  14. Are Urinary PAHs Biomarkers of Controlled Exposure to Diesel Exhaust?

    EPA Science Inventory

    Urinary polycyclic aromatic hydrocarbons (PAHs) were evaluated as possible biomarkers of exposure to diesel exhaust (DE) in two controlled-chamber studies. We report levels of 14 PAHs from 28 subjects in urine that were collected before, immediately after and the morning after ex...

  15. DIESEL EXHAUST EXPOSURE INCREASES SEVERITY OF AN ONGOING INFLUENZA INFECTION

    EPA Science Inventory

    Numerous studies have shown that air pollutants including diesel exhaust (DE) alter host defense responses, resulting in decreased resistance to respiratory infection. The purpose of this study was to evaluate the effects of DE exposure on the severity of an ongoing influenza in...

  16. Exposure to Diesel Exhaust Enhances the Generation of Vascular Microparticles

    EPA Science Inventory

    Introduction: In the study of the health impacts of traffic-related air pollution, diesel exhaust is a pollutant of particular interest, since it is a major source of particulate matter (PM). Epidemiological studies associate exposure to ambient levels of PM with cardiovascular m...

  17. Diesel Exhaust Particle-Exposed Human Bronchial Epithelial Cells Induce Dendritic Cell Maturation and Polarization via Thymic Stromal Lymphopoietin

    PubMed Central

    Bleck, Bertram; Tse, Doris B.; Curotto de Lafaille, Maria A.; Zhang, Feijie

    2009-01-01

    Human exposure to air pollutants, including ambient particulate matter, has been proposed as a mechanism for the rise in allergic disorders. Diesel exhaust particles, a major component of ambient particulate matter, induce sensitization to neoallergens, but the mechanisms by which sensitization occur remain unclear. We show that diesel exhaust particles upregulate thymic stromal lymphopoietin in human bronchial epithelial cells in an oxidant-dependent manner. Thymic stromal lymphopoietin induced by diesel exhaust particles was associated with maturation of myeloid dendritic cells, which was blocked by anti-thymic stromal lymphopoietin antibodies or silencing epithelial cell-derived thymic stromal lymphopoietin. Dendritic cells exposed to diesel exhaust particle-treated human bronchial epithelial cells induced Th2 polarization in a thymic stromal lymphopoietin-dependent manner. These findings provide new insight into the mechanisms by which diesel exhaust particles modify human lung mucosal immunity. PMID:18049884

  18. [Exposure to nanoparticle-rich diesel exhaust affects hippocampal functions in mice].

    PubMed

    Win-Shwe, Tin Tin; Fujitani, Yuji; Hirano, Seishiro; Fujimaki, Hidekazu

    2011-09-01

    Epidemiological studies have indicated associations between day-to-day particulate air pollution and increased risks of various adverse health outcomes. Although an association between exposure to diesel exhaust particles (DEPs) and the development of pulmonary inflammation has been reported, there are limited reports on the neurotoxic effects of DEPs, particularly those of nanoparticle-rich diesel exhaust (NRDE). In this minireview, we highlighted the effects of NRDE which was generated in the National Institute for Environmental Studies, on hippocampus-dependent spatial learning ability and the expression of memory-function-related genes, neurotrophins, and proinflammatory cytokines in a mouse model. PMID:21996758

  19. Exhaust particle removing system for an internal combustion engine

    SciTech Connect

    Shinzawa, M.

    1986-08-05

    An exhaust particle removing system is described for an internal combustion engine, comprising: (a) a filter disposed in an engine exhaust passage for trapping particles suspended in exhaust gas; (b) a burner for burning off the particles deposited on the filter; (c) means for sensing the pressure in the exhaust passage at a point upstream of the filter; (d) means for sensing the pressure in the exhaust passage at a point downstream of the filter; (e) means for determining whether or not the sensed upstream pressure is lower than a preset level; (f) means for, when the sensed upstream pressure is not lower than the preset level, deducing the degree of clogging of the filter on the basis of the sensed upstream and downstream pressures; (g) means for, when the sensed upstream pressure is lower than the preset level, measuring a time elapsed since the moment at which the sensed upstream pressure dropped below the preset level; (h) means for, when the sensed upstream pressure is lower than the preset level, deducing the degree of clogging of the filter on the basis of the time elapsed and the sensed upstream and downstream pressures obtained immediately prior to the moment at which the sensed upstream pressure dropped below the preset level; and (i) means for controlling the burner on the basis of the deduced degree of clogging of the filter.

  20. Occupational exposure to diesel engine exhaust: A literature review

    PubMed Central

    Pronk, Anjoeka; Coble, Joseph; Stewart, Patricia

    2010-01-01

    Background Diesel exhaust (DE) is classified as a probable human carcinogen. Aims were to describe the major occupational uses of diesel engines and give an overview of personal DE exposure levels and determinants of exposure as reported in the published literature. Methods Measurements representative of personal DE exposure were abstracted from the literature for the following agents: elemental carbon (EC), particulate matter (PM), carbon monoxide (CO), nitrogen oxide (NO), and nitrogen dioxide (NO2). Information on determinants of exposure was abstracted. Results In total, 3528 EC, 4166 PM, 581 CO, 322 NO, and 1404 NO2 measurements were abstracted. From the 10,001 measurements, 32% represented exposure from on-road vehicles, and 68% from off-road vehicles (30% mining, 15% railroad, and 22% other). Highest levels were reported for enclosed underground work sites where heavy equipment is used: mining, mine maintenance, and construction, (EC: 27-658 μg/m3). Intermediate exposure levels were generally reported for above ground (semi-)enclosed areas where smaller equipment was run: mechanics in a shop, emergency workers in fire stations, distribution workers at a dock, and workers loading/unloading inside a ferry (generally: EC< 50 μg/m3). Lowest levels were reported for enclosed areas separated from the source such as drivers and train crew, or outside such as surface mining, parking attendants, vehicle testers, utility service workers, surface construction and airline ground personnel (EC<25 μg/m3). The other agents showed a similar pattern. Determinants of exposure reported for enclosed situations were ventilation and exhaust after treatment devices. Conclusions Reported DE exposure levels were highest for underground mining and construction, intermediate for working in above ground (semi-)enclosed areas and lowest for working outside or separated from the source. The presented data can be used as a basis for assessing occupational exposure in population

  1. Occupational exposure to diesel engine exhaust: a literature review.

    PubMed

    Pronk, Anjoeka; Coble, Joseph; Stewart, Patricia A

    2009-07-01

    Diesel exhaust (DE) is classified as a probable human carcinogen. Aims were to describe the major occupational uses of diesel engines and give an overview of personal DE exposure levels and determinants of exposure as reported in the published literature. Measurements representative of personal DE exposure were abstracted from the literature for the following agents: elemental carbon (EC), particulate matter (PM), carbon monoxide (CO), nitrogen oxide (NO), and nitrogen dioxide (NO(2)). Information on determinants of exposure was abstracted. In total, 3528 EC, 4166 PM, 581 CO, 322 NO, and 1404 NO(2) measurements were abstracted. From the 10,001 measurements, 32% represented exposure from on-road vehicles and 68% from off-road vehicles (30% mining, 15% railroad, and 22% others). Highest levels were reported for enclosed underground work sites in which heavy equipment is used: mining, mine maintenance, and construction (EC: 27-658 microg/m(3)). Intermediate exposure levels were generally reported for above-ground (semi-) enclosed areas in which smaller equipment was run: mechanics in a shop, emergency workers in fire stations, distribution workers at a dock, and workers loading/unloading inside a ferry (generally: EC<50 microg/m(3)). Lowest levels were reported for enclosed areas separated from the source, such as drivers and train crew, or outside, such as surface mining, parking attendants, vehicle testers, utility service workers, surface construction and airline ground personnel (EC<25 microg/m(3)). The other agents showed a similar pattern. Determinants of exposure reported for enclosed situations were ventilation and exhaust after treatment devices. Reported DE exposure levels were highest for underground mining and construction, intermediate for working in above-ground (semi-) enclosed areas and lowest for working outside or separated from the source. The presented data can be used as a basis for assessing occupational exposure in population

  2. Mutagenicity of Diesel and Soy Biodiesel Exhaust Particles

    EPA Science Inventory

    Mutagenicity Of Diesel And Soy Biodiesel Exhaust Particles E Mutlua,b' SH Warrenb, PP Matthewsb, CJ Kingb, B Prestonc, MD Haysb, DG Nashb,ct, WP Linakb, MI Gilmourb, and DM DeMarinib aUniversity of North Carolina, Chapel Hill, NC bU.S. Environmental Agency, Research Triangle Pa...

  3. EFFECT OF OZONE ON DIESEL EXHAUST PARTICLE TOXICITY

    EPA Science Inventory

    Ambient particulate matter (PM) concentrations have been associated with mortality and morbidity. Diesel exhaust particles (DEP) are present in ambient urban air PM. Coexisting with DEP (and PM) is ozone (O(3)), which has the potential to react with some components of DEP. Some r...

  4. The Differential Oxidative Properties of Diesel Exhaust Particles

    EPA Science Inventory

    Diesel exhaust particles (DEP) accounts for a significant percentage of particulate matter (PM) released into the atmosphere and are associated with adverse pulmonary effects. Due to their extremely small size and high surface area, DEP can adsorb toxic substances, thus potentia...

  5. Exhaust particle removing system for an internal combustion engine

    SciTech Connect

    Shinzawa, M.

    1988-07-12

    An exhaust particle removing system is described for an engine, comprising: (a) a filter for trapping particles in exhaust from the engine; (b) means for determining whether or not the degree of clogging of the filter is unacceptable; (c) means for detecting an operating condition of the engine; (d) means for when the degree of clogging of the filter is unacceptable, throttling the flow of intake air into the engine and thus varying the pressure of the intake air in accordance with the detected engine operating condition in cases where the detected engine operating condition resides in a first predetermined range within which the temperature of the engine exhaust would be inadequate to burn off the trapped particles if the intake air flow were not throttled, the throttling means comprising a movable throttle valve disposed in an air intake passage, a bypass passage connected to the air intake passage and bypassing the throttle valve, and a movable bypass valve disposed in the bypass passage; and (e) means for, when the degree of clogging of the filter is unacceptable, allowing free flow of the intake air in cases where the detected engine operating condition resides in a second predetermined range within which the temperature of the engine exhaust would be adequate to burn off the trapped particles even if the intake air flow were not throttled.

  6. In situ exhaust cloud measurements. [particle size distribution and cloud physics of rocket exhaust clouds

    NASA Technical Reports Server (NTRS)

    Wornom, D.

    1980-01-01

    Airborne in situ exhaust cloud measurements were conducted to obtain definitions of cloud particle size range, Cl2 content, and HCl partitioning. Particle size distribution data and Cl2 measurements were made during the May, August, and September 1977 Titan launches. The measurements of three basic effluents - HCl, NO sub X, and particles - against minutes after launch are plotted. The maximum observed HCl concentration to the maximum Cl2 concentration are compared and the ratios of the Cl2 to the HCl is calculated.

  7. Tracking personal exposure to particulate diesel exhaust in a diesel freight terminal using organic tracer analysis

    PubMed Central

    SHEESLEY, REBECCA J.; SCHAUER, JAMES J.; GARSHICK, ERIC; LADEN, FRANCINE; SMITH, THOMAS J.; BLICHARZ, ANDREW P.; DEMINTER, JEFFREY T.

    2008-01-01

    Personal exposure to particle-phase molecular markers was measured at a trucking terminal in St Louis, MO, as part of a larger epidemiologic project aimed at assessing carbonaceous fine particulate matter (PM) exposure in this occupational setting. The integration of parallel personal exposure, ambient worksite area and ambient urban background (St Louis Supersite) measurements provided a unique opportunity to track the work-related exposure to carbonaceous fine PM in a freight terminal. The data were used to test the proposed personal exposure model in this occupational setting: Personal exposure=urban background+work site background+personal activity To accurately assess the impact of PM emission sources, particularly motor vehicle exhaust, and organic elemental carbon (OCEC) analysis and nonpolar organic molecular marker analysis by thermal desorption-gas chromatography/mass spectrometry (TD-GCMS) were conducted on all of the PM samples. EC has been used as a tracer for diesel exhaust in urban areas, however, the emission profile for diesel exhaust is dependent upon the operating conditions of the vehicle and can vary considerably within a fleet. Hopanes, steranes, polycyclic aromatic hydrocarbons and alkanes were measured by TD-GCMS. Hopanes are source-specific organic molecular markers for lubricating oil present in motor vehicle exhaust. The concentrations of OC, EC and the organic tracers were averaged to obtain average profiles to assess differences in the personal, worksite area and urban background samples, and were also correlated individually by sample time to evaluate the exposure model presented above. Finally, a chemical mass balance model was used to apportion the motor vehicle and cigarette-smoke components of the measured OC and EC for the average personal exposure, worksite area and urban background samples. PMID:18322451

  8. Ice nucleus activity measurements of solid rocket motor exhaust particles

    NASA Technical Reports Server (NTRS)

    Keller, V. W. (Compiler)

    1986-01-01

    The ice Nucleus activity of exhaust particles generated from combustion of Space Shuttle propellant in small rocket motors has been measured. The activity at -20 C was substantially lower than that of aerosols generated by unpressurized combustion of propellant samples in previous studies. The activity decays rapidly with time and is decreased further in the presence of moist air. These tests corroborate the low effectivity ice nucleus measurement results obtained in the exhaust ground cloud of the Space Shuttle. Such low ice nucleus activity implies that Space Shuttle induced inadvertent weather modification via an ice phase process is extremely unlikely.

  9. Diesel exhaust exposure in the Canadian railroad work environment.

    PubMed

    Verma, Dave K; Finkelstein, Murray M; Kurtz, Lawrence; Smolynec, Kathy; Eyre, Susan

    2003-01-01

    An investigation of occupational exposure to diesel exhaust, in terms of elemental carbon, was conducted as part of a feasibility study in the Canadian railroad industry. Both personal and area samples were collected from three major operating divisions of the railways: mechanical service, transportation, and engineering. A total of 255 elemental carbon samples have been described. The results show that all but six elemental carbon concentrations, expressed as size-selective respirable air samples taken using a 10 mm nylon cyclone, are well below the 2001 proposed American Conference of Governmental Industrial Hygienists' (ACGIH) threshold limit value (TLV) of 20 microg/m3. The concentration of diesel exhaust, expressed as elemental carbon, in the railroad industry is much lower than that in some other major industries such as mining and forklift truck operations. If the TLV is to be applicable to a broad range of workplace settings such as railroad, construction, and mining, the use of a TLV that is based on an elemental carbon measurement of size selective respirable samples, as recommended in the 2001 ACGIH proposal, would appear to be the most valid strategy for control of exposure to diesel exhaust. PMID:12650546

  10. Symptoms in Response to Controlled Diesel Exhaust More Closely Reflect Exposure Perception Than True Exposure

    PubMed Central

    Carlsten, Chris; Oron, Assaf P.; Curtiss, Heidi; Jarvis, Sara; Daniell, William; Kaufman, Joel D.

    2013-01-01

    Background Diesel exhaust (DE) exposures are very common, yet exposure-related symptoms haven’t been rigorously examined. Objective Describe symptomatic responses to freshly generated and diluted DE and filtered air (FA) in a controlled human exposure setting; assess whether such responses are altered by perception of exposure. Methods 43 subjects participated within three double-blind crossover experiments to order-randomized DE exposure levels (FA and DE calibrated at 100 and/or 200 micrograms/m3 particulate matter of diameter less than 2.5 microns), and completed questionnaires regarding symptoms and dose perception. Results For a given symptom cluster, the majority of those exposed to moderate concentrations of diesel exhaust do not report such symptoms. The most commonly reported symptom cluster was of the nose (29%). Blinding to exposure is generally effective. Perceived exposure, rather than true exposure, is the dominant modifier of symptom reporting. Conclusion Controlled human exposure to moderate-dose diesel exhaust is associated with a range of mild symptoms, though the majority of individuals will not experience any given symptom. Blinding to DE exposure is generally effective. Perceived DE exposure, rather than true DE exposure, is the dominant modifier of symptom reporting. PMID:24358296

  11. Tracking personal exposure to particulate diesel exhaust in a diesel freight terminal using organic tracer analysis.

    PubMed

    Sheesley, Rebecca J; Schauer, James J; Garshick, Eric; Laden, Francine; Smith, Thomas J; Blicharz, Andrew P; Deminter, Jeffrey T

    2009-02-01

    Personal exposure to particle-phase molecular markers was measured at a trucking terminal in St Louis, MO, as part of a larger epidemiologic project aimed at assessing carbonaceous fine particulate matter (PM) exposure in this occupational setting. The integration of parallel personal exposure, ambient worksite area and ambient urban background (St Louis Supersite) measurements provided a unique opportunity to track the work-related exposure to carbonaceous fine PM in a freight terminal. The data were used to test the proposed personal exposure model in this occupational setting: To accurately assess the impact of PM emission sources, particularly motor vehicle exhaust, and organic elemental carbon (OCEC) analysis and nonpolar organic molecular marker analysis by thermal desorption-gas chromatography/mass spectrometry (TD-GCMS) were conducted on all of the PM samples. EC has been used as a tracer for diesel exhaust in urban areas, however, the emission profile for diesel exhaust is dependent upon the operating conditions of the vehicle and can vary considerably within a fleet. Hopanes, steranes, polycyclic aromatic hydrocarbons and alkanes were measured by TD-GCMS. Hopanes are source-specific organic molecular markers for lubricating oil present in motor vehicle exhaust. The concentrations of OC, EC and the organic tracers were averaged to obtain average profiles to assess differences in the personal, worksite area and urban background samples, and were also correlated individually by sample time to evaluate the exposure model presented above. Finally, a chemical mass balance model was used to apportion the motor vehicle and cigarette-smoke components of the measured OC and EC for the average personal exposure, worksite area and urban background samples. PMID:18322451

  12. Sulfuric Acid and Soot Particle Formation in Aircraft Exhaust

    NASA Technical Reports Server (NTRS)

    Pueschel, Rudolf F.; Verma, S.; Ferry, G. V.; Howard, S. D.; Vay, S.; Kinne, S. A.; Baumgardner, D.; Dermott, P.; Kreidenweis, S.; Goodman, J.; Gore, Waren J. Y. (Technical Monitor)

    1997-01-01

    A combination of CN counts, Ames wire impactor size analyses and optical particle counter data in aircraft exhaust results in a continuous particle size distribution between 0.01 micrometer and 1 micrometer particle radius sampled in the exhaust of a Boeing 757 research aircraft. The two orders of magnitude size range covered by the measurements correspond to 6-7 orders of magnitude particle concentration. CN counts and small particle wire impactor data determine a nucleation mode, composed of aircraft-emitted sulfuric acid aerosol, that contributes between 62% and 85% to the total aerosol surface area and between 31% and 34% to its volume. Soot aerosol comprises 0.5% of the surface area of the sulfuric acid aerosol. Emission indices are: EIH2SO4 = 0.05 g/kgFUEL and (0.2-0.5) g/kgFUEL (for 75 ppmm and 675 ppmm fuel-S, respectively), 2.5E4particles/kgFUEL (for 75 and 675 ppmm fuel-S). The sulfur (gas) to H2SO4 (particle) conversion efficiency is between 10% and 25%.

  13. Estimation of the diesel exhaust exposures of railroad workers. I. Current exposures

    SciTech Connect

    Woskie, S.R.; Smith, T.J.; Hammond, S.K.; Schenker, M.B.; Garshick, E.; Speizer, F.E.

    1988-01-01

    As a part of a series of epidemiological studies of railroad workers, measurements were made to characterize workers' exposures to diesel exhaust. Since diesel exhaust is not a single compound, an exposure marker was sought. The personal exposures to respirable particulate matter (RPM) of over 530 workers in 39 common jobs were measured in four U.S. railroads over a three-year period. Significant amounts of cigarette smoke (20-90%) were found in many of these samples. Therefore, the respirable particulate concentration, adjusted to remove the fraction of cigarette smoke (ARP), was chosen as a marker of diesel exhaust exposures. The geometric mean exposures to ARP ranged from 17 micrograms/m3 for clerks to 134 micrograms/m3 for locomotive shop workers. Significant interrailroad variations were observed in some job groups indicating that the different facilities, equipment, and work practices found among the railroads can affect a worker's exposure to diesel exhaust. Climate was also found to have a significant effect on exposure in some job groups.

  14. Diesel exhaust exposure and lung cancer: a case-control study

    SciTech Connect

    Hall, N.E.L.; Wynder, E.L.

    1984-06-01

    The presence of polyaromatic hydrocarbons in the particulate phase of diesel engine exhaust has raised questions concerning potential carcinogenicity of diesel exhaust exposure. A case-control study was conducted of 502 male lung cancer cases and 502 controls without tobacco-related diseases to investigate the association of occupational diesel exhaust exposure and lung cancer. Diesel exhaust exposure was appraised by job title. The results show no association between diesel exhaust exposure and risk of lung cancer. They do, however, show the strong association between smoking and lung cancer and as such highlight the importance of smoking information in studies of occupational effect on lung cancer risk.

  15. Infant leukemia and paternal exposure to motor vehicle exhaust fumes

    SciTech Connect

    Vianna, N.J.; Kovasznay, B.; Polan, A.; Ju, C.

    1984-09-01

    The children of fathers who work in gas stations, automobile or truck repair, and aircraft maintenance appear to be at increased risk for acute leukemia during their first year of life. The odds ratio was found to be about 2.5 overall, but risk appears to be greater for female offspring. A decline in sex ratio was observed for the three decades of the study, with the lowest ratio observed from 1969 through 1978. These preliminary findings suggest that exposure to one or more of the components of exhaust fumes might be of etiologic importance for this malignancy. The limitations of this investigation are discussed.

  16. Laser-induced incandescence measurements of particles in aeroengine exhausts

    NASA Astrophysics Data System (ADS)

    Black, John D.

    1999-09-01

    Laser Induced Incandescence (LII) has been demonstrated as a non-intrusive technique for measurement of particle concentration in the exhausts of aero-engines on sea level test beds as part of a European Union collaborative program (AEROJET) aimed at replacing gas sampling rakes behind development engines with non-intrusive instrumentation. Currently emissions of CO, NOx, unburned hydrocarbon, and smoke from aero-engines must be shown to be less than internationally specified limits. Measurements are made on development engines on sea level test beds by applying a number of standard analytical methods to extracted exhaust gas samples. The hardware required for exhaust gas sampling is heavy and complex and is expensive to build and install. As a result, only the minimum number of emissions tests are conducted during an engine development program, and emissions data is only available to combustion engineers late in the program. Hence, there is a need for more versatile and less costly non-intrusive measurement techniques. Molecular species can be measured using Fourier Transform Infrared (FTIR) spectroscopy, while LII is a promising smoke measuring technique. The development of an LII system specifically designed for exhaust applications is described.

  17. Microscopic characterization of individual particles from multicomponent ship exhaust.

    PubMed

    Popovicheva, Olga; Kireeva, Elena; Persiantseva, Natalia; Timofeev, Mikhail; Bladt, Henrike; Ivleva, Natalia P; Niessner, Reinhard; Moldanová, Jana

    2012-12-01

    Particles sampled from the main and auxiliary ship diesel engine exhausts during a measurement campaign aboard a cargo ship are studied by SEM and energy-dispersive X-ray (EDX) microanalysis. Cluster analysis (CA) is applied to characterize the particles by separating them into distinct groups of similar morphology and chemical composition, representative of the particle types in the exhaust from the main and auxiliary engines. Raman microspectroscopy, Fourier transform infrared (FTIR) spectroscopy, inductively coupled plasma mass spectrometry and ion chromatography provide the criteria for the clustering of a large data set of individual particles. To identify chemical and morphological features of heavy and distillate fuel oil-derived PM emissions, micromarkers discriminating between the different types of emitted particles are proposed. These micromarkers could enable the classification of multicomponent aerosols according to a source type. This characterization of complex multicomponent aerosols emitted by ship diesel engines improves the quantification of the contribution of shipping to ambient air particulates, and can help to identify a source type in apportionment studies. PMID:23090431

  18. Automobile diesel exhaust particles induce lipid droplet formation in macrophages in vitro.

    PubMed

    Cao, Yi; Jantzen, Kim; Gouveia, Ana Cecilia Damiao; Skovmand, Astrid; Roursgaard, Martin; Loft, Steffen; Møller, Peter

    2015-07-01

    Exposure to diesel exhaust particles (DEP) has been associated with adverse cardiopulmonary health effects, which may be related to dysregulation of lipid metabolism and formation of macrophage foam cells. In this study, THP-1 derived macrophages were exposed to an automobile generated DEP (A-DEP) for 24h to study lipid droplet formation and possible mechanisms. The results show that A-DEP did not induce cytotoxicity. The production of reactive oxygen species was only significantly increased after exposure for 3h, but not 24h. Intracellular level of reduced glutathione was increased after 24h exposure. These results combined indicate an adaptive response to oxidative stress. Exposure to A-DEP was associated with significantly increased formation of lipid droplets, as well as changes in lysosomal function, assessed as reduced LysoTracker staining. In conclusion, these results indicated that exposure to A-DEP may induce formation of lipid droplets in macrophages in vitro possibly via lysosomal dysfunction. PMID:26122084

  19. DIESEL EXHAUST PARTICLES SUPRESS LPS-STIMULATED PRODUCTION OF PGE2 IN HUMAN ALVEOLAR MACHROPHAGES: ROLE OF P38 MAPK AND ERK PATHWAYS

    EPA Science Inventory

    Numerous studies have reported association between exposure to ambient levels of particulate matter (PM) and adverse health effects, which include respiratory and cardiovascular effects. Diesel exhaust particles (DEP) compose a significant fraction of PM in some areas. Alveolar m...

  20. SUPPRESSION OF BASAL AND CYTOKINE INDUCED EXPRESSION OF ANTIGEN PRESENTATION MARKERS ON MOUSE LUNG EPITHELIAL CELLS EXPOSED TO DIESEL EXHAUST PARTICLES.

    EPA Science Inventory

    Diesel exhaust particles (DEP) constitute a significant component of airborne particulates in urban environment. Exposure to DEP is known to enhance susceptibility to viral and bacterial infections. We hypothesized that DEP could partially exert its effect on disease susceptibili...

  1. *Differential injury in healthy and cytokine-treated epithelial cells exposed to diesel exhaust particles involves interaction of superoxide and nitric oxide

    EPA Science Inventory

    RATIONALE: Individuals with chronic pulmonary inflammation due to disease are more susceptible to the adverse health effects associated with exposure to particulate matter (PM) air pollutants, such as diesel exhaust particles (DEP). Increasing evidence suggests that these adverse...

  2. Allergic inflammation in the human lower respiratory tract affected by exposure to diesel exhaust.

    PubMed

    Riedl, Marc A; Diaz-Sanchez, David; Linn, William S; Gong, Henry; Clark, Kenneth W; Effros, Richard M; Miller, J Wayne; Cocker, David R; Berhane, Kiros T

    2012-02-01

    To improve understanding of human health risks from exposure to diesel exhaust particles (DEP*), we tested whether immunologic effects previously observed in the human nose also occur in the lower airways. Our overall hypothesis was that cell influx and production of cytokines, chemokines, immunoglobulin E (IgE), and other mediators, which would be measurable in sputum and blood, occur in people with asthma after realistic controlled exposures to diesel exhaust (DE). In Phase 1 we tested for direct effects of DE in subjects with clinically undifferentiated mild asthma. In Phase 2 we tested whether DE exposure would exacerbate response to inhaled cat allergen in subjects with both asthma and cat sensitivity. The exposure facility was a controlled-environment chamber supplied with DE from an idling medium-duty truck with ultra-low-sulfur fuel and no catalytic converter. We exposed volunteers for 2 hours with intermittent exercise to exhaust with DEP mass concentration near 100 microg/m3. Exposures to nitrogen dioxide (NO2) near 0.35 ppm (similar to its concentration in DE) and to filtered air (FA) served as controls. Blood was drawn before exposure on day 1 and again the next morning (day 2). Sputum was induced only on day 2. Bronchial reactivity was measured -1 hour after exposure ended. Supplementary endpoints included measures of blood coagulation status, cardiopulmonary physiology, and symptoms. Each phase employed 15 subjects with asthma; 3 subjects participated in both phases. In Phase 1, airway reactivity was measured with inhaled methacholine; in Phase 2, with inhaled cat allergen. We found little biologic response to DE exposure compared with exposure to control atmospheres. In Phase 1, interleukin 4 (IL-4) in sputum showed an estimated 1.7-fold increase attributable to DE exposure, which was close to statistical significance; airway resistance increased modestly but significantly on day 2 after DE exposure; and nonspecific symptom scores increased

  3. [Ultrafine particle number concentration and size distribution of vehicle exhaust ultrafine particles].

    PubMed

    Lu, Ye-qiang; Chen, Qiu-fang; Sun, Zai; Cai, Zhi-liang; Yang, Wen-jun

    2014-09-01

    Ultrafine particle (UFP) number concentrations obtained from three different vehicles were measured using fast mobility particle sizer (FMPS) and automobile exhaust gas analyzer. UFP number concentration and size distribution were studied at different idle driving speeds. The results showed that at a low idle speed of 800 rmin-1 , the emission particle number concentration was the lowest and showed a increasing trend with the increase of idle speed. The majority of exhaust particles were in Nuclear mode and Aitken mode. The peak sizes were dominated by 10 nm and 50 nm. Particle number concentration showed a significantly sharp increase during the vehicle acceleration process, and was then kept stable when the speed was stable. In the range of 0. 4 m axial distance from the end of the exhaust pipe, the particle number concentration decayed rapidly after dilution, but it was not obvious in the range of 0. 4-1 m. The number concentration was larger than the background concentration. Concentration of exhaust emissions such as CO, HC and NO showed a reducing trend with the increase of idle speed,which was in contrast to the emission trend of particle number concentration. PMID:25518646

  4. Susceptibility of inflamed ariway and alveolar epithelial cells to injury induced by diesel exhaust particles of varying organic carbon content

    EPA Science Inventory

    Exposure to traffic-related ambient air pollution, such as diesel exhaust particles (DEP), is associated with adverse health outcomes, especially in individuals with preexisting inflammatory respiratory diseases. Using an analogous in vitro system to model both the healthy and a...

  5. *Assessing differential transcriptional regulation of IL-8 expression by human airway epithelial cells exposed to diesel exhaust particles

    EPA Science Inventory

    Background: Exposure to Diesel Exhaust Particles (DEP) induces inflammatory signaling characterized by MAP kinase-mediated activation of NFkB and AP-l in vitro and in bronchial biopsies obtained from human subjects exposed to DEP. NFkB and AP-l activation results in the upregulat...

  6. Identification of Surrogate Measures of Diesel Exhaust Exposure in a Controlled Chamber Study

    EPA Science Inventory

    Exposure to diesel exhaust (DE) has been associated with acute cardiopulmonary and vascular responses, chronic noncancer health effects, and respiratory cancers in humans. To better understand DE exposures and eventually their related health effects, we established a controlled c...

  7. Diesel Exhaust Exposure and Nasal Response to Attenuated Influenza in Normal and Allergic Volunteers

    EPA Science Inventory

    Rationale: Diesel exhaust enhances allergic inflammation, and pollutants are associated with heightened susceptibility to viral respiratory infections. The effects of combined diesel and virus exposure in humans are unknown. Objective: Test whether acute exposure to diesel modif...

  8. AN ENGINE EXHAUST PARTICLE SIZERTM SPECTROMETER FOR TRANSIENT EMISSION PARTICLE MEASUREMENTS

    SciTech Connect

    Johnson, T; Caldow, R; Pucher, A; Mirme, A; Kittelson, D

    2003-08-24

    There has been increased interest in obtaining size distribution data during transient engine operation where both particle size and total number concentrations can change dramatically. Traditionally, the measurement of particle emissions from vehicles has been a compromise based on choosing between the conflicting needs of high time resolution or high particle size resolution for a particular measurement. Currently the most common technique for measuring submicrometer particle sizes is the Scanning Mobility Particle Sizer (SMPSTM) system. The SMPS system gives high size resolution but requires an aerosol to be stable over a long time period to make a particle size distribution measurement. A Condensation Particle Counter (CPC) is commonly used for fast time response measurements but is limited to measuring total concentration only. This paper describes a new instrument, the Engine Exhaust Particle SizerTM (EEPSTM) spectrometer, which has high time resolution and a reasonable size resolution. The EEPS was designed specifically for measuring engine exhaust and, like the SMPS system, uses a measurement based on electrical mobility. Particles entering the instrument are charged to a predictable level, then passed through an annular space where they are repelled outward by the voltage from a central column. When the particles reach electrodes on the outer cylindrical (a column of rings), they create a current that is measured by an electrometer on one or more of the rings. The electrometer currents are measured multiple times per second to give high time resolution. A sophisticated realtime inversion algorithm converts the currents to particle size and concentration for immediate display.

  9. AN ENGINE EXHAUST PARTICLE SIZER{trademark} SPECTROMETER FOR TRANSIENT EMISSION PARTICLE MEASUREMENTS

    SciTech Connect

    Johnson, T: Caldow, R; Pucher, A Mirme, A Kittelson, D

    2003-08-24

    There has been increased interest in obtaining size distribution data during transient engine operation where both particle size and total number concentrations can change dramatically. Traditionally, the measurement of particle emissions from vehicles has been a compromise based on choosing between the conflicting needs of high time resolution or high particle size resolution for a particular measurement. Currently the most common technique for measuring submicrometer particle sizes is the Scanning Mobility Particle Sizer (SMPSTM) system. The SMPS system gives high size resolution but requires an aerosol to be stable over a long time period to make a particle size distribution measurement. A Condensation Particle Counter (CPC) is commonly used for fast time response measurements but is limited to measuring total concentration only. This paper describes a new instrument, the Engine Exhaust Particle SizerTM (EEPSTM) spectrometer, which has high time resolution and a reasonable size resolution. The EEPS was designed specifically for measuring engine exhaust and, like the SMPS system, uses a measurement based on electrical mobility. Particles entering the instrument are charged to a predictable level, then passed through an annular space where they are repelled outward by the voltage from a central column. When the particles reach electrodes on the outer cylindrical (a column of rings), they create a current that is measured by an electrometer on one or more of the rings. The electrometer currents are measured multiple times per second to give high time resolution. A sophisticated realtime inversion algorithm converts the currents to particle size and concentration for immediate display.

  10. Mutagenicity of diesel exhaust particle extracts: influence of driving cycle and environmental temperature.

    PubMed

    Clark, C R; Dutcher, J S; Brooks, A L; McClellan, R O; Marshall, W F; Naman, T M

    1982-01-01

    General Motors and Volkswagen diesel passenger cars (1980 and 1981 model year) were operated on a climate controlled chassis dynomometer and the particulate portion of the exhaust was collected on high volume filters. Dichloromethane extracts of the exhaust particles (soot) collected while the cars were operated under simulated highway, urban and congested urban driving cycles were assayed for mutagenicity in Salmonella strains TA-98 and TA-100. Driving pattern did not significantly influence the mutagenic potency of the exhaust particle extracts or estimates of the amount of mutagenicity emitted from the exhaust despite large differences in particle emission rates and extractable fraction of the particles. Mutagenicity of extracts of exhaust particles collected while the vehicles were operated at test chamber temperatures of 25, 50, 75 and 100 degrees F were also very similar. The results suggest that driving pattern and environmental temperature do not significantly alter the emission of genotoxic combustion products from the exhaust. PMID:6193022

  11. Reduction in adverse effect on pulmonary function after exposure to filtered diesel exhaust

    SciTech Connect

    Ulfvarson, U.; Alexandersson, R. )

    1990-01-01

    A statistically significant temporary reduction on pulmonary function was measured with spirometry in stevedores on a roll-on-roll-off ro-ro ship who were exposed to diesel exhausts from trucks during a work shift. When all trucks were equipped with specially designed microfilters mounted on the exhaust pipes, this impairment in pulmonary function was reduced. Removal of the particulate fraction of the exhausts by filtering is an important factor in reducing the adverse effect of diesel exhaust on pulmonary function. The particle fraction should be considered when designing an indicator of the biological effects of diesel exhausts.

  12. Myocardial infarction and occupational exposure to motor exhaust: a population-based case-control study in Sweden.

    PubMed

    Ilar, Anna; Lewné, Marie; Plato, Nils; Hallqvist, Johan; Alderling, Magnus; Bigert, Carolina; Hogstedt, Christer; Gustavsson, Per

    2014-07-01

    There is a well-established association between particulate urban air pollution and cardiovascular disease, but few studies have investigated the risk associated with occupational exposure to particles from motor exhaust. This study investigated the risk of myocardial infarction (MI) after occupational exposure to motor exhaust, using elemental carbon (EC) as a marker of exposure. A population-based case-control study of first-time non-lethal MI was conducted among Swedish citizens in ages 45-70 living in Stockholm County 1992-1994, including 1,643 cases and 2,235 controls. Working histories and data on potential confounders were collected by questionnaire and medical examination. The exposure to EC was assessed through a job-exposure matrix. Odds ratios (ORs) and corresponding 95% confidence intervals (CIs) were estimated by unconditional logistic regression. We investigated various exposure metrics: intensity, cumulative exposure and years since exposure. There was an exposure-response relation between the highest average exposure intensity during the work history and the risk of MI when adjusting for smoking and alcohol drinking (p for trend 0.034), with an OR of 1.30 (95% CI 0.99-1.71) in the highest tertile of exposure compared to the unexposed. An exposure-response pattern was observed in the analysis of years since exposure cessation among formerly exposed. Additional adjustments for markers of the metabolic syndrome reduced ORs and trends to non-significant levels, although this might be an over-adjustment since the metabolic syndrome may be part of the causal pathway. Occupational exposure to motor exhaust was associated with a moderately increased risk of MI. PMID:24981789

  13. Exacerbation of allergic inflammation in mice exposed to diesel exhaust particles prior to viral infection.

    EPA Science Inventory

    Background: Viral infections and exposure to oxidant air pollutants are two ofthe most important inducers ofasthma exacerbation. Our previous studies have demonstrated that exposure to diesel exhaust increases the susceptibility to influenza virus infections both in epithelial ce...

  14. Cerium dioxide nanoparticles can interfere with the associated cellular mechanistic response to diesel exhaust exposure.

    PubMed

    Steiner, Sandro; Mueller, Loretta; Popovicheva, Olga B; Raemy, David O; Czerwinski, Jan; Comte, Pierre; Mayer, Andreas; Gehr, Peter; Rothen-Rutishauser, Barbara; Clift, Martin J D

    2012-10-17

    The aim of this study was to compare the biological response of a sophisticated in vitro 3D co-culture model of the epithelial airway barrier to a co-exposure of CeO(2) NPs and diesel exhaust using a realistic air-liquid exposure system. Independent of the individual effects of either diesel exhaust or CeO(2) NPs investigation observed that a combined exposure of CeO(2) NPs and diesel exhaust did not cause a significant cytotoxic effect or alter cellular morphology after exposure to diesel exhaust for 2h at 20μg/ml (low dose) or for 6h at 60μg/ml (high dose), and a subsequent 6h exposure to an aerosolized solution of CeO(2) NPs at the same doses. A significant loss in the reduced intracellular glutathione level was recorded, although a significant increase in the oxidative marker HMOX-1 was found after exposure to a low and high dose respectively. Both the gene expression and protein release of tumour necrosis factor-α were significantly elevated after a high dose exposure only. In conclusion, CeO(2) NPs, in combination with diesel exhaust, can significantly interfere with the cell machinery, indicating a specific, potentially adverse role of CeO(2) NPs in regards to the biological response of diesel exhaust exposure. PMID:22960666

  15. INCREASED SUSCEPTIBILITY TO INFLUENZA INFECTION AFTER DIESEL EXHAUST EXPOSURE

    EPA Science Inventory

    Inhaled environmental pollutants have a possible role in modulating the susceptibility of humans to respiratory infections. Diesel exhaust (DE) is a major component of urban air pollution and their effects on pulmonary infections is of great concern. Influenza infections cause ...

  16. INCREASED SUSCEPTIBILITY TO INFLUENZA INFECTION AFTER DIESEL EXHAUST EXPOSURE.

    EPA Science Inventory

    Inhaled environmental pollutants have a possible role in modulating the susceptibility of humans to respiratory infections. Diesel exhaust (DE) is a major component of urban air pollution and their effects on pulmonary infections is of great concern. Influenza infections cause ...

  17. Inhibition of catalase activity in vitro by diesel exhaust particles

    SciTech Connect

    Mori, Yoki; Murakami, Sumika; Sagae, Toshiyuki

    1996-02-09

    The effect of diesel exhaust particles (DEP) on the activity of catalase, an intracellular anti-oxidant, was investigated because H{sub 2}O{sub 2} is a cytotoxic oxidant, and catalase released from alveolar cells is an important antioxidant in the epithelial lining fluid in the lung. DEP inhibited the activity of bovine liver catalase dose-dependently, to 25-30% of its original value. The inhibition of catalase by DEP was observed only in the presence of anions such as Cl{sup {minus}}, Br{sup {minus}}, or thiocyanate. Other anions, such as CH{sub 3}COO{sup {minus}} or SO{sub 4}{sup {minus}}, and cations such as K{sup +}, Na{sup +}, Mg{sup 2+}, or Fe{sup 2+}, did not affect the activity of catalase, even in the presence of DEP extract. Catalase from guinea pig alveolar cells and catalase from red blood cells were also inhibited by DEP extracts, as was catalase from bovine liver. These results suggest that DEP taken up in the lung and located on alveolar spaces might cause cell injury by inhibiting the activity of catalase in epithelial lining fluid, enhancing the toxicity of H{sub 2}O{sub 2} generated from cells in addition to that of O{sub 2}{sup {minus}} generated by the chemical reaction of DEP with oxygen. 10 refs., 6 figs.

  18. Exposure to inhalable, respirable, and ultrafine particles in welding fume.

    PubMed

    Lehnert, Martin; Pesch, Beate; Lotz, Anne; Pelzer, Johannes; Kendzia, Benjamin; Gawrych, Katarzyna; Heinze, Evelyn; Van Gelder, Rainer; Punkenburg, Ewald; Weiss, Tobias; Mattenklott, Markus; Hahn, Jens-Uwe; Möhlmann, Carsten; Berges, Markus; Hartwig, Andrea; Brüning, Thomas

    2012-07-01

    This investigation aims to explore determinants of exposure to particle size-specific welding fume. Area sampling of ultrafine particles (UFP) was performed at 33 worksites in parallel with the collection of respirable particles. Personal sampling of respirable and inhalable particles was carried out in the breathing zone of 241 welders. Median mass concentrations were 2.48 mg m(-3) for inhalable and 1.29 mg m(-3) for respirable particles when excluding 26 users of powered air-purifying respirators (PAPRs). Mass concentrations were highest when flux-cored arc welding (FCAW) with gas was applied (median of inhalable particles: 11.6 mg m(-3)). Measurements of particles were frequently below the limit of detection (LOD), especially inside PAPRs or during tungsten inert gas welding (TIG). However, TIG generated a high number of small particles, including UFP. We imputed measurements exposure to welding fume. Concentrations were mainly predicted by the welding process and were significantly higher when local exhaust ventilation (LEV) was inefficient or when welding was performed in confined spaces. Substitution of high-emission techniques like FCAW, efficient LEV, and using PAPRs where applicable can reduce exposure to welding fume. However, harmonizing the different exposure metrics for UFP (as particle counts) and for the respirable or inhalable fraction of the welding fume (expressed as their mass) remains challenging. PMID:22539559

  19. Exposure to Inhalable, Respirable, and Ultrafine Particles in Welding Fume

    PubMed Central

    Pesch, Beate

    2012-01-01

    This investigation aims to explore determinants of exposure to particle size-specific welding fume. Area sampling of ultrafine particles (UFP) was performed at 33 worksites in parallel with the collection of respirable particles. Personal sampling of respirable and inhalable particles was carried out in the breathing zone of 241 welders. Median mass concentrations were 2.48 mg m−3 for inhalable and 1.29 mg m−3 for respirable particles when excluding 26 users of powered air-purifying respirators (PAPRs). Mass concentrations were highest when flux-cored arc welding (FCAW) with gas was applied (median of inhalable particles: 11.6 mg m−3). Measurements of particles were frequently below the limit of detection (LOD), especially inside PAPRs or during tungsten inert gas welding (TIG). However, TIG generated a high number of small particles, including UFP. We imputed measurements exposure to welding fume. Concentrations were mainly predicted by the welding process and were significantly higher when local exhaust ventilation (LEV) was inefficient or when welding was performed in confined spaces. Substitution of high-emission techniques like FCAW, efficient LEV, and using PAPRs where applicable can reduce exposure to welding fume. However, harmonizing the different exposure metrics for UFP (as particle counts) and for the respirable or inhalable fraction of the welding fume (expressed as their mass) remains challenging. PMID:22539559

  20. BIOMarkers for occupational diesel exhaust exposure monitoring (BIOMODEM)--a study in underground mining.

    PubMed

    Scheepers, P T J; Coggon, D; Knudsen, L E; Anzion, R; Autrup, H; Bogovski, S; Bos, R P; Dahmann, D; Farmer, P; Martin, E A; Micka, V; Muzyka, V; Neumann, H G; Poole, J; Schmidt-Ott, A; Seiler, F; Volf, J; Zwirner-Baier, I

    2002-08-01

    Methods for the assessment of exposures to diesel exhaust were evaluated, including various biomarkers of internal exposure and early biological effects. The impact of possible biomarkers of susceptibility was also explored. Underground workers (drivers of diesel-powered excavators) at an oil shale mine in Estonia were compared with surface workers. Personal exposures to particle-associated 1-nitropyrene (NP) were some eight times higher underground than on the surface. Underground miners were also occupationally exposed to benzene and polycyclic aromatic hydrocarbons, as indicated by excretion of urinary metabolites of benzene and pyrene. In addition, increased O(6)-alkylguanine DNA adducts were detected in the white blood cells of underground workers, suggesting higher exposure to nitroso-compounds. However, no differences between underground and surface workers were observed in the levels of other bulky DNA adducts determined by 32P-postlabelling, or in DNA damage. The study indicated that smoking, diet and residential indoor air pollution are important non-occupational factors to consider when interpreting biomonitoring results. PMID:12191893

  1. Factors and Trends Affecting the Identification of a Reliable Biomarker for Diesel Exhaust Exposure

    PubMed Central

    2014-01-01

    The monitoring of human exposures to diesel exhaust continues to be a vexing problem for specialists seeking information on the potential health effects of this ubiquitous combustion product. Exposure biomarkers have yielded a potential solution to this problem by providing a direct measure of an individual's contact with key components in the exhaust stream. Spurred by the advent of new, highly sensitive, analytical methods capable of detecting substances at very low levels, there have been numerous attempts at identifying a stable and specific biomarker. Despite these new techniques, there is currently no foolproof method for unambiguously separating diesel exhaust exposures from those arising from other combustion sources. Diesel exhaust is a highly complex mixture of solid, liquid, and gaseous components whose exact composition can be affected by many variables, including engine technology, fuel composition, operating conditions, and photochemical aging. These factors together with those related to exposure methodology, epidemiological necessity, and regulatory reform can have a decided impact on the success or failure of future research aimed at identifying a suitable biomarker of exposure. The objective of this review is to examine existing information on exposure biomarkers for diesel exhaust and to identify those factors and trends that have had an impact on the successful identification of metrics for both occupational and community settings. The information will provide interested parties with a template for more thoroughly understanding those factors affecting diesel exhaust emissions and for identifying those substances and research approaches holding the greatest promise for future success. PMID:25170242

  2. Factors and Trends Affecting the Identification of a Reliable Biomarker for Diesel Exhaust Exposure.

    PubMed

    Morgott, David A

    2014-08-01

    The monitoring of human exposures to diesel exhaust continues to be a vexing problem for specialists seeking information on the potential health effects of this ubiquitous combustion product. Exposure biomarkers have yielded a potential solution to this problem by providing a direct measure of an individual's contact with key components in the exhaust stream. Spurred by the advent of new, highly sensitive, analytical methods capable of detecting substances at very low levels, there have been numerous attempts at identifying a stable and specific biomarker. Despite these new techniques, there is currently no foolproof method for unambiguously separating diesel exhaust exposures from those arising from other combustion sources. Diesel exhaust is a highly complex mixture of solid, liquid, and gaseous components whose exact composition can be affected by many variables, including engine technology, fuel composition, operating conditions, and photochemical aging. These factors together with those related to exposure methodology, epidemiological necessity, and regulatory reform can have a decided impact on the success or failure of future research aimed at identifying a suitable biomarker of exposure. The objective of this review is to examine existing information on exposure biomarkers for diesel exhaust and to identify those factors and trends that have had an impact on the successful identification of metrics for both occupational and community settings. The information will provide interested parties with a template for more thoroughly understanding those factors affecting diesel exhaust emissions and for identifying those substances and research approaches holding the greatest promise for future success. PMID:25170242

  3. Size-Resolved Ultrafine Particle Deposition and Brownian Coagulation from Gasoline Vehicle Exhaust in an Environmental Test Chamber.

    PubMed

    Zhao, Yu; Wang, Fang; Zhao, Jianing

    2015-10-20

    Size-resolved deposition rates and Brownian coagulation of particles between 20 and 900 nm (mobility diameter) were estimated in a well-mixed environmental chamber from a gasoline vehicle exhaust with a total peak particle concentration of 10(5)-10(6) particles/cm(3) at 12.24-25.22 °C. A deposition theory with modified friction velocity and coagulation model was also employed to predict particle concentration decay. Initially during particle decay, approximately 85% or more of the particles had diameters of <100 nm. Particle deposition rates with standard deviations were highly dependent on particle size ranges, and varied from 0.012 ± 0.003 to 0.48 ± 0.02 h(-1). In the experiment, the friction velocity obtained was in the range 1.5-2.5 cm/s. The most explainable fractal dimension and Hamaker constant in coagulation model were 2.5-3 and 20 kT, respectively, and the contribution from coagulation dominated the total particle decay during the first 1 h of decay. It is considered that the modified friction velocity and best fitted fractal dimension and Hamaker constants could be further used to analyze gasoline vehicle exhaust particle dynamics and assess human exposure to vehicle particle pollutants in urban areas, tunnels, and underground parking lots. PMID:26402743

  4. Control of Nitrous Oxide Exposure in Dental Operatories Using Local Exhaust Ventilation

    PubMed Central

    Jacobs, David E.; Middendorf, Paul J.

    1986-01-01

    An experimental portable local exhaust ventilation system was installed in three dental operatories where nitrous oxide was used routinely. Standard methods of exhaust ventilation design used in industry to control exposures to toxic airborne substances were applied to the dental operatory setting. The concentration of nitrous oxide in the dentists' breathing zones was measured before and after installation to determine the efficiency of the system in reducing occupational exposures. Results indicate that placement of the exhaust opening and exhaust air flow rate are important in determining the degree of control achieved. After the system had been installed in one operatory, peak exposures declined from over 600 parts per million (ppm) to less than 70 ppm: the time-weighted average exposure was below the NIOSH recommended level of 25 ppm. A permanently installed local exhaust ventilation system modeled after the portable one used in this pilot study may be feasible for most operatories and should not interfere with dental procedures. The results suggest that nitrous oxide exposures can be greatly reduced if dental operatories are equipped with local exhaust ventilation. ImagesFig. 4Fig. 7 PMID:3465259

  5. Blood pressure response to controlled diesel exhaust exposure in human subjects.

    PubMed

    Cosselman, Kristen E; Krishnan, Ranjini M; Oron, Assaf P; Jansen, Karen; Peretz, Alon; Sullivan, Jeffrey H; Larson, Timothy V; Kaufman, Joel D

    2012-05-01

    Exposure to traffic-related air pollution is associated with risk of cardiovascular disease and mortality. We examined whether exposure to diesel exhaust increased blood pressure (BP) in human subjects. We analyzed data from 45 nonsmoking subjects, 18 to 49 years of age in double-blinded, crossover exposure studies, randomized to order. Each subject was exposed to diesel exhaust, maintained at 200 μg/m(3) of fine particulate matter, and filtered air for 120 minutes on days separated by ≥2 weeks. We measured BP pre-exposure, at 30-minute intervals during exposure, and 3, 5, 7, and 24 hours from exposure initiation and analyzed changes from pre-exposure values. Compared with filtered air, systolic BP increased at all of the points measured during and after diesel exhaust exposure; the mean effect peaked between 30 and 60 minutes after exposure initiation (3.8 mm Hg [95% CI: -0.4 to 8.0 mm Hg] and 5.1 mm Hg [95% CI: 0.7-9.5 mm Hg], respectively). Sex and metabolic syndrome did not modify this effect. Combining readings between 30 and 90 minutes, diesel exhaust exposure resulted in a 4.4-mm Hg increase in systolic BP, adjusted for participant characteristics and exposure perception (95% CI: 1.1-7.7 mm Hg; P=0.0009). There was no significant effect on heart rate or diastolic pressure. Diesel exhaust inhalation was associated with a rapid, measurable increase in systolic but not diastolic BP in young nonsmokers, independent of perception of exposure. This controlled trial in humans confirms findings from observational studies. The effect may be important on a population basis given the worldwide prevalence of exposure to traffic-related air pollution. PMID:22431582

  6. The generation of diesel exhaust particle aerosols from a bulk source in an aerodynamic size range similar to atmospheric particles

    PubMed Central

    Cooney, Daniel J; Hickey, Anthony J

    2008-01-01

    The influence of diesel exhaust particles (DEP) on the lungs and heart is currently a topic of great interest in inhalation toxicology. Epidemiological data and animal studies have implicated airborne particulate matter and DEP in increased morbidity and mortality due to a number of cardiopulmonary diseases including asthma, chronic obstructive pulmonary disorder, and lung cancer. The pathogeneses of these diseases are being studied using animal models and cell culture techniques. Real-time exposures to freshly combusted diesel fuel are complex and require significant infrastructure including engine operations, dilution air, and monitoring and control of gases. A method of generating DEP aerosols from a bulk source in an aerodynamic size range similar to atmospheric DEP would be a desirable and useful alternative. Metered dose inhaler technology was adopted to generate aerosols from suspensions of DEP in the propellant hydrofluoroalkane 134a. Inertial impaction data indicated that the particle size distributions of the generated aerosols were trimodal, with count median aerodynamic diameters less than 100 nm. Scanning electron microscopy of deposited particles showed tightly aggregated particles, as would be expected from an evaporative process. Chemical analysis indicated that there were no major changes in the mass proportion of 2 specific aromatic hydrocarbons (benzo[a]pyrene and benzo[k]fluoranthene) in the particles resulting from the aerosolization process. PMID:19337412

  7. Biological Responses to Diesel Exhaust Particles (DEPs) Depend on the Physicochemical Properties of the DEPs

    PubMed Central

    Park, Eun-Jung; Roh, Jinkyu; Kang, Min-Sung; Kim, Soo Nam; Kim, Younghun; Choi, Sangdun

    2011-01-01

    Diesel exhaust particles (DEPs) are the main components of ambient particulate materials, including polyaromatic hydrocarbons (PAHs), n-PAHs, heavy metals, and gaseous materials. Many epidemiological, clinical, and toxicological studies have shown that ambient particles, including DEPs, are associated with respiratory disorders, such as asthma, allergic rhinitis, and lung cancer. However, the relationship between the biological response to DEPs and their chemical composition remains unclear. In this study, we investigated the physicochemical properties of DEPs before toxicological studies, and then administered a single intratracheal instillation of DEPs to mice. The mice were then killed 1, 7, 14 and 28 days after DEP exposure to observe the biological responses induced by DEPs over time. Our findings suggest that DEPs engulfed into cells induced a Th2-type inflammatory response followed by DNA damage, whereas DEPs not engulfed into cells induced a Th1-type inflammatory response. Further, the physicochemical properties, including surface charge, particle size, and chemical composition, of DEPs play a crucial role in determining the biological responses to DEPs. Consequently, we suggest that the biological response to DEPs depend on cell-particle interaction and the physicochemical properties of the particles. PMID:22039547

  8. Penetration of diesel exhaust particles through commercially available dust half masks.

    PubMed

    Penconek, Agata; Drążyk, Paulina; Moskal, Arkadiusz

    2013-04-01

    Half masks are certified by the competent, national institutions--National Institute for Occupational Safety and Health (NIOSH) in the USA and the respective European national institutions applying common European regulations. However, certification testing is conducted with particles of NaCl, paraffin oil, or dioctyl phthalate (DOP) and at the constant flow rate, whereas particles commonly found in workplaces may differ in size, shape, and morphology from these particles. Therefore, the aim of this study was to investigate filtration efficiency of commercially available filtering facepiece half masks under the condition of exposure to diesel fumes. In this study, we focused on the particulate phase [diesel exhaust particles (DEP)] of three (petroleum diesel, ecodiesel, and biodiesel) diesel fuel combustion types. Two types of European standard-certified half masks, FFP2 and FFP - Filtering Facepiece, and three types of popular diesel fuels were tested. The study showed that the filtration efficiencies for each examined half mask and for each of diesel exhaust fumes were lower than the minimum filtration efficiency required for the standard test aerosols by the European standards. For FFP2 and FFP3 particulate half masks, standard minimum filtration efficiency is 94 and 99%, respectively, whereas 84-89% of mass of DEP from various fuels were filtered by the tested FFP2 and only 75-86% by the FFP3. The study indicated that DEP is more penetrating for these filters than the standard salt or paraffin oil test aerosols. The study also showed that the most penetrating DEP are probably in the 30- to 300-nm size range, regardless of the fuel type and the half-mask model. Finally, the pressure drops across both half masks during the 80-min tests remained below an acceptable maximum of breathing resistance-regardless of the fuel types. The respiratory system, during 40-min test exposures, may be exposed to 12-16mg of DEP if a FFP2 or FFP3 particulate half mask is used. To

  9. Diesel exhaust particles induce endothelial dysfunction in apoE{sup -/-} mice

    SciTech Connect

    Hansen, Christian S.; Sheykhzade, Majid; Moller, Peter; Folkmann, Janne Kjaergaard; Amtorp, Ole; Jonassen, Thomas; Loft, Steffen . E-mail: s.loft@pubhealth.ku.dk

    2007-02-15

    Background: Particulate air pollution can aggravate cardiovascular disease by mechanisms suggested to involve translocation of particles to the bloodstream and impairment of endothelial function, possibly dependent on present atherosclerosis. Aim: We investigated the effects of exposure to diesel exhaust particles (DEP) in vivo and ex vivo on vasomotor functions in aorta from apoE{sup -/-} mice with slight atherosclerosis and from normal apoE{sup +/+} mice. Methods: DEP 0, 0.5 or 5 mg/kg bodyweight in saline was administered i.p. The mice were sacrificed 1 h later and aorta ring segments were mounted on wire myographs. Segments from unexposed mice were also incubated ex vivo with 0, 10 and 100 {mu}g DEP/ml before measurement of vasomotor functions. Results: Exposure to 0.5 mg/kg DEP in vivo caused a decrease in the endothelium-dependent acetylcholine elicited vasorelaxation in apoE{sup -/-} mice, whereas the response was enhanced in apoE{sup +/+} mice. No significant change was observed after administration of 5 mg/kg DEP. In vivo DEP exposure did not affect constriction induced by K{sup +} or phenylephrine. In vitro exposure to 100 {mu}g DEP/ml enhanced acetylcholine-induced relaxation and attenuated phenylephrine-induced constriction. Vasodilation induced by sodium nitroprusside was not affected by any DEP exposure. Conclusion: Exposure to DEP has acute effect on vascular functions. Endothelial dysfunction possibly due to decreased NO production as suggested by decreased acetylcholine-induced vasorelaxation and unchanged sodium nitroprusside response can be induced by DEP in vivo only in vessels of mice with some atherosclerosis.

  10. RISK ASSESSMENT OF THE INFLAMMOGENIC AND MUTAGENIC EFFECTS OF DIESEL EXHAUST PARTICLES: A SYSTEMS BIOLOGY APPROACH

    EPA Science Inventory

    Diesel exhaust particulate matter (DEP) is a ubiquitous ambient air contaminant derived from mobile and stationary diesel fuel combustion. Exposure to DEP is associated with carcinogenic and immunotoxic effects in humans and experimental animals. At the cellular level, these heal...

  11. Diesel exhaust but not ozone increases fraction of exhaled nitric oxide in a randomized controlled experimental exposure study of healthy human subjects

    PubMed Central

    2013-01-01

    Background Fraction of exhaled nitric oxide (FENO) is a promising non-invasive index of airway inflammation that may be used to assess respiratory effects of air pollution. We evaluated FENO as a measure of airway inflammation after controlled exposure to diesel exhaust or ozone. Methods Healthy volunteers were exposed to either diesel exhaust (particle concentration 300 μg/m3) and filtered air for one hour, or ozone (300 ppb) and filtered air for 75 minutes. FENO was measured in duplicate at expiratory flow rates of 10, 50, 100 and 270 mL/s before, 6 and 24 hours after each exposure. Results Exposure to diesel exhaust increased FENO at 6 hours compared with air at expiratory flow rates of 10 mL/s (p = 0.01) and at 50 mL/s (p = 0.011), but FENO did not differ significantly at higher flow rates. Increases in FENO following diesel exhaust were attenuated at 24 hours. Ozone did not affect FENO at any flow rate or time point. Conclusions Exposure to diesel exhaust, but not ozone, increased FENO concentrations in healthy subjects. Differences in the induction of airway inflammation may explain divergent responses to diesel exhaust and ozone, with implications for the use of FENO as an index of exposure to air pollution. PMID:23602059

  12. Design and testing of Electrostatic Aerosol in Vitro Exposure System (EAVES): an alternative exposure system for particles.

    PubMed

    de Bruijne, K; Ebersviller, S; Sexton, K G; Lake, S; Leith, D; Goodman, R; Jetters, J; Walters, G W; Doyle-Eisele, M; Woodside, R; Jeffries, H E; Jaspers, I

    2009-02-01

    Conventional in vitro exposure methods for cultured human lung cells rely on prior suspension of particles in a liquid medium; these have limitations for exposure intensity and may modify the particle composition. Here electrostatic precipitation was used as an effective method for such in vitro exposures. An obsolete electrostatic aerosol sampler was modified to provide a viable environment within the deposition field for human lung cells grown on membranous support. Particle deposition and particle-induced toxicological effects for a variety of particles including standardized polystyrene latex spheres (PSL) and diesel exhaust emission particle mixtures are reported. The Electrostatic Aerosol in Vitro Exposure System (EAVES) efficiently deposited particles from an air stream directly onto cells. Cells exposed to the electric field of the EAVES in clean air or in the presence of charged PSL spheres exhibited minimal cytotoxicity, and their release of inflammatory cytokines was indistinguishable from that of the controls. For the responses tested here, there are no significant adverse effects caused neither by the electric field alone nor by the mildly charged particles. Exposure to diesel exhaust emissions using the EAVES system induced a threefold increase in cytokines and cytotoxicity as compared to the control. Taken together, these data show that the EAVES can be used to expose human lung cells directly to particles without prior collection in media, thereby providing an efficient and effective alternative to the more conventional particle in vitro exposure methods. PMID:18800273

  13. Reduction in (pro-)inflammatory responses of lung cells exposed in vitro to diesel exhaust treated with a non-catalyzed diesel particle filter

    NASA Astrophysics Data System (ADS)

    Steiner, Sandro; Czerwinski, Jan; Comte, Pierre; Müller, Loretta L.; Heeb, Norbert V.; Mayer, Andreas; Petri-Fink, Alke; Rothen-Rutishauser, Barbara

    2013-12-01

    Increasingly stringent regulation of particulate matter emissions from diesel vehicles has led to the widespread use of diesel particle filters (DPFs), the effect of which on exhaust toxicity is so far poorly understood. We exposed a cellular model of the human respiratory epithelium at the air-liquid interface to non-catalyzed wall-flow DPF-filtered diesel exhaust and compared the resulting biological responses to the ones observed upon exposure to unfiltered exhaust. Filtered diesel exhaust acted highly oxidative, even though to a lesser extent than unfiltered exhaust (quantification of total reduced glutathione), and both exhaust types triggered comparable responses to oxidative stress (measurement of heme-oxygenase 1 (HMOX1) and superoxide-dismutase (SOD1) gene expression). Further, diesel exhaust filtration significantly reduced pro-inflammatory responses (measurement of tumor necrosis factor (TNF) and interleukin-8 (IL-8) gene expression and quantification of the secretion of their gene products TNF-α and IL-8). Because inflammatory processes are central to the onset of adverse respiratory health effects caused by diesel exhaust inhalation, our results imply that DPFs may make a valuable contribution to the detoxification of diesel vehicle emissions. The induction of significant oxidative stress by filtered diesel exhaust however, also implies that the non-particulate exhaust components also need to be considered for lung cell risk assessment.

  14. Retrospective cohort study of lung cancer and diesel exhaust exposure in railroad workers

    SciTech Connect

    Garshick, E.; Schenker, M.B.; Munoz, A.; Segal, M.; Smith, T.J.; Woskie, S.R.; Hammond, S.K.; Speizer, F.E.

    1988-04-01

    The risk of lung cancer as a result of exposure to diesel exhaust from railroad locomotives was assessed in a cohort of 55,407 white male railroad workers 40 to 64 yr of age in 1959 who had started railroad service 10 to 20 years earlier. The cohort was traced until the end of 1980, and death certificates were obtained for 88% of 19,396 deaths; 1694 lung cancer cases were identified. Yearly railroad job from 1959 to death or retirement was available from the Railroad Retirement Board, and served as an index of diesel exhaust exposure. Directly standardized rates and a proportional hazards model were used to calculate the relative risk of lung cancer based on work in a job with diesel exhaust exposure beginning in 1959. A relative risk of 1.45 (95% CI = 1.11, 1.89) for lung cancer was obtained in the group of workers 40 to 44 yr of age in 1959, the group with the longest possible duration of diesel exposure. The cohort was selected to minimize the effect of past railroad asbestos exposure, and analysis with workers with possible asbestos exposure excluded resulted in a similarly elevated risk. Workers with 20 yr or more elapsed since 1959, the effective start of diesel exposure for the cohort, had the highest relative risk. These results taken in conjunction with other reported results support the hypothesis that occupational exposure to diesel exhaust results in a small but significantly elevated risk for lung cancer.

  15. Health effects of real-world exposure to diesel exhaust in persons with asthma.

    PubMed

    Zhang, Junfeng Jim; McCreanor, James E; Cullinan, Paul; Chung, Kian Fan; Ohman-Strickland, Pamela; Han, In-Kyu; Järup, Lars; Nieuwenhuijsen, Mark J

    2009-02-01

    Many people, including people with asthma, experience short-term exposure to diesel exhaust (DE*) during daily activities. The health effects of such exposures, however, remain poorly understood. The present study utilized a real-world setting to examine whether short-term DE exposure would (1) worsen asthma symptoms, (2) augment airway inflammation, or (3) increase oxidative stress burdens. The study also examined exposure-response relations for several DE components and the contribution of background asthma severity to individuals' respiratory responses to DE exposure. Sixty people participated in the study; 31 had mild asthma and 29 had moderate asthma. Each participant completed an exposure and a control session. During the exposure session, participants walked for 2 hours along a heavily trafficked city street where motor vehicle access was restricted to buses and official taxicabs. These vehicles were powered by diesel engines. During the control session, participants walked for the same duration and at the same speed in a public park where motor vehicle traffic was prohibited. The concentrations of elemental carbon (EC), NO2, ultrafine particles (UFP), and particulate matter less than or equal to 2.5 microm in aerodynamic diameter (PM2.5) during exposure sessions were, on average, 4.8, 4.0, 3.4, and 2.0 times higher, respectively, than during control sessions. Increases in asthma symptom score and in the daily use of asthma reliever medication within the 7-day measurement period after exposure were not significant. Some effects on lung function were statistically significant. Compared with control sessions, forced expiratory volume in the first second (FEV1) was reduced 3.0% to 4.1%, and forced vital capacity (FVC) was reduced 2.8% to 3.7% in the 5 hours immediately after the exposure sessions. Analyses of biomarkers showed that the exposure sessions led to a significant reduction in exhaled breath condensate (EBC) pH and to significant increases in induced

  16. Social Isolation-Induced Territorial Aggression in Male Offspring Is Enhanced by Exposure to Diesel Exhaust during Pregnancy

    PubMed Central

    Yokota, Satoshi; Oshio, Shigeru; Moriya, Nozomu; Takeda, Ken

    2016-01-01

    Diesel exhaust particles are a major component of ambient particulate matter, and concern about the health effects of exposure to ambient particulate matter is growing. Previously, we found that in utero exposure to diesel exhaust affected locomotor activity and motor coordination, but there are also indications that such exposure may contribute to increased aggression in offspring. Therefore, the aim of the present study was to test the effects of prenatal diesel exhaust exposure on social isolation-induced territorial aggression. Pregnant mice were exposed to low concentrations of diesel exhaust (DE; mass concentration of 90 μg/m3: DE group: n = 15) or clean air (control group: n = 15) for 8 h/day during gestation. Basal locomotion of male offspring was measured at 10 weeks of age. Thereafter, male offspring were individually housed for 2 weeks and subsequently assessed for aggression using the resident−intruder test at 12 weeks of age, and blood and brain tissue were collected from the male offspring on the following day for measuring serum testosterone levels and neurochemical analysis. There were no significant differences in locomotion between control and DE-exposed mice. However, DE-exposed mice showed significantly greater social isolation-induced territorial aggressive behavior than control mice. Additionally, socially-isolated DE-exposed mice expressed significantly higher concentrations of serum testosterone levels than control mice. Neurochemical analysis revealed that dopamine levels in the prefrontal cortex and nucleus accumbens were higher in socially isolated DE-exposed mice. Serotonin levels in the nucleus accumbens, amygdala, and hypothalamus were also lower in the socially isolated DE-exposed mice than in control mice. Thus, even at low doses, prenatal exposure to DE increased aggression and serum testosterone levels, and caused neurochemical changes in male socially isolated mice. These results may have serious implications for pregnant women

  17. Social Isolation-Induced Territorial Aggression in Male Offspring Is Enhanced by Exposure to Diesel Exhaust during Pregnancy.

    PubMed

    Yokota, Satoshi; Oshio, Shigeru; Moriya, Nozomu; Takeda, Ken

    2016-01-01

    Diesel exhaust particles are a major component of ambient particulate matter, and concern about the health effects of exposure to ambient particulate matter is growing. Previously, we found that in utero exposure to diesel exhaust affected locomotor activity and motor coordination, but there are also indications that such exposure may contribute to increased aggression in offspring. Therefore, the aim of the present study was to test the effects of prenatal diesel exhaust exposure on social isolation-induced territorial aggression. Pregnant mice were exposed to low concentrations of diesel exhaust (DE; mass concentration of 90 μg/m3: DE group: n = 15) or clean air (control group: n = 15) for 8 h/day during gestation. Basal locomotion of male offspring was measured at 10 weeks of age. Thereafter, male offspring were individually housed for 2 weeks and subsequently assessed for aggression using the resident-intruder test at 12 weeks of age, and blood and brain tissue were collected from the male offspring on the following day for measuring serum testosterone levels and neurochemical analysis. There were no significant differences in locomotion between control and DE-exposed mice. However, DE-exposed mice showed significantly greater social isolation-induced territorial aggressive behavior than control mice. Additionally, socially-isolated DE-exposed mice expressed significantly higher concentrations of serum testosterone levels than control mice. Neurochemical analysis revealed that dopamine levels in the prefrontal cortex and nucleus accumbens were higher in socially isolated DE-exposed mice. Serotonin levels in the nucleus accumbens, amygdala, and hypothalamus were also lower in the socially isolated DE-exposed mice than in control mice. Thus, even at low doses, prenatal exposure to DE increased aggression and serum testosterone levels, and caused neurochemical changes in male socially isolated mice. These results may have serious implications for pregnant women

  18. The Diesel Exhaust in Miners Study: II. Exposure monitoring surveys and development of exposure groups.

    PubMed

    Coble, Joseph B; Stewart, Patricia A; Vermeulen, Roel; Yereb, Daniel; Stanevich, Rebecca; Blair, Aaron; Silverman, Debra T; Attfield, Michael

    2010-10-01

    Air monitoring surveys were conducted between 1998 and 2001 at seven non-metal mining facilities to assess exposure to respirable elemental carbon (REC), a component of diesel exhaust (DE), for an epidemiologic study of miners exposed to DE. Personal exposure measurements were taken on workers in a cross-section of jobs located underground and on the surface. Air samples taken to measure REC were also analyzed for respirable organic carbon (ROC). Concurrent measurements to assess exposure to nitric oxide (NO) and nitrogen dioxide (NO₂), two gaseous components of DE, were also taken. The REC measurements were used to develop quantitative estimates of average exposure levels by facility, department, and job title for the epidemiologic analysis. Each underground job was assigned to one of three sets of exposure groups from specific to general: (i) standardized job titles, (ii) groups of standardized job titles combined based on the percentage of time in the major underground areas, and (iii) larger groups based on similar area carbon monoxide (CO) air concentrations. Surface jobs were categorized based on their use of diesel equipment and proximity to DE. A total of 779 full-shift personal measurements were taken underground. The average REC exposure levels for underground jobs with five or more measurements ranged from 31 to 58 μg m⁻³ at the facility with the lowest average exposure levels and from 313 to 488 μg m⁻³ at the facility with the highest average exposure levels. The average REC exposure levels for surface workers ranged from 2 to 6 μg m⁻³ across the seven facilities. There was much less contrast in the ROC compared with REC exposure levels measured between surface and underground workers within each facility, as well as across the facilities. The average ROC levels underground ranged from 64 to 195 μg m⁻³, while on the surface, the average ROC levels ranged from 38 to 71 μg m⁻³ by facility, an ∼2- to 3-fold difference. The average

  19. Particle analysis of car exhaust by ETV-ICP-MS.

    PubMed

    Lüdke, C; Hoffmann, E; Skole, J; Artelt, S

    1996-06-01

    Particulates of platinum group elements (Pt, Rh, Pd, Ir) emitted in automotive catalyst exhaust were measured down to the pg/m(3) level. Samples were taken from a standard type three-way catalyst equipped gasoline engine, running on a computer controlled dynamometer. Particulates in catalyzed car exhaust were sampled fractionated according to size by using the cascade impactor with separate targets mounted underneath each nozzle. The targets, small flat discs made of pure graphite, were subsequently analyzed by ETV-ICP-MS without any preparatory steps. PMID:15045379

  20. The Diesel Exhaust in Miners Study: II. Exposure Monitoring Surveys and Development of Exposure Groups

    PubMed Central

    Coble, Joseph B.; Stewart, Patricia A.; Vermeulen, Roel; Yereb, Daniel; Stanevich, Rebecca; Blair, Aaron; Silverman, Debra T.; Attfield, Michael

    2010-01-01

    Air monitoring surveys were conducted between 1998 and 2001 at seven non-metal mining facilities to assess exposure to respirable elemental carbon (REC), a component of diesel exhaust (DE), for an epidemiologic study of miners exposed to DE. Personal exposure measurements were taken on workers in a cross-section of jobs located underground and on the surface. Air samples taken to measure REC were also analyzed for respirable organic carbon (ROC). Concurrent measurements to assess exposure to nitric oxide (NO) and nitrogen dioxide (NO2), two gaseous components of DE, were also taken. The REC measurements were used to develop quantitative estimates of average exposure levels by facility, department, and job title for the epidemiologic analysis. Each underground job was assigned to one of three sets of exposure groups from specific to general: (i) standardized job titles, (ii) groups of standardized job titles combined based on the percentage of time in the major underground areas, and (iii) larger groups based on similar area carbon monoxide (CO) air concentrations. Surface jobs were categorized based on their use of diesel equipment and proximity to DE. A total of 779 full-shift personal measurements were taken underground. The average REC exposure levels for underground jobs with five or more measurements ranged from 31 to 58 μg m−3 at the facility with the lowest average exposure levels and from 313 to 488 μg m−3 at the facility with the highest average exposure levels. The average REC exposure levels for surface workers ranged from 2 to 6 μg m−3 across the seven facilities. There was much less contrast in the ROC compared with REC exposure levels measured between surface and underground workers within each facility, as well as across the facilities. The average ROC levels underground ranged from 64 to 195 μg m−3, while on the surface, the average ROC levels ranged from 38 to 71 μg m−3 by facility, an ∼2- to 3-fold difference. The average NO and

  1. Sample characterization of automobile and forklift diesel exhaust particles and comparative pulmonary toxicity in mice.

    PubMed Central

    Singh, Pramila; DeMarini, David M; Dick, Colin A J; Tabor, Dennis G; Ryan, Jeff V; Linak, William P; Kobayashi, Takahiro; Gilmour, M Ian

    2004-01-01

    Two samples of diesel exhaust particles (DEPs) predominate in health effects research: an automobile-derived DEP (A-DEP) sample and the National Institute of Standards Technology standard reference material (SRM 2975) generated from a forklift engine. A-DEPs have been tested extensively for their effects on pulmonary inflammation and exacerbation of allergic asthmalike responses. In contrast, SRM 2975 has been tested thoroughly for its genotoxicity. In the present study, we combined physical and chemical analyses of both DEP samples with pulmonary toxicity testing in CD-1 mice to compare the two materials and to make associations between their physicochemical properties and their biologic effects. A-DEPs had more than 10 times the amount of extractable organic material and less than one-sixth the amount of elemental carbon compared with SRM 2975. Aspiration of 100 micro g of either DEP sample in saline produced mild acute lung injury; however, A-DEPs induced macrophage influx and activation, whereas SRM 2975 enhanced polymorphonuclear cell inflammation. A-DEPs stimulated an increase in interleukin-6 (IL-6), tumor necrosis factor alpha, macrophage inhibitory protein-2, and the TH2 cytokine IL-5, whereas SRM 2975 only induced significant levels of IL-6. Fractionated organic extracts of the same quantity of DEPs (100 micro g) did not have a discernable effect on lung responses and will require further study. The disparate results obtained highlight the need for chemical, physical, and source characterization of particle samples under investigation. Multidisciplinary toxicity testing of diesel emissions derived from a variety of generation and collection conditions is required to meaningfully assess the health hazards associated with exposures to DEPs. Key words: automobile, diesel exhaust particles, forklift, mice, pulmonary toxicity, SRM 2975. PMID:15175167

  2. Effects of diesel exhaust particles on microRNA-21 in human bronchial epithelial cells and potential carcinogenic mechanisms.

    PubMed

    Zhou, Fang; Li, Suli; Jia, Wenliang; Lv, Gang; Song, Chonglin; Kang, Chunsheng; Zhang, Qingyu

    2015-08-01

    Air pollution plays a role in cancer risk, particularly in lung cancer, which is the leading cause of cancer-related mortality worldwide. Diesel exhaust particles (DEPs), a component of diesel exhaust products, is a complex mixture of particle compounds that include a large number of known and suspected human carcinogens. Historically, lung cancer, which is associated with DEPs, has been the focus of attention as a health risk in human and animal studies. However, the mechanism by which DEPs cause lung cancer remains unclear. The present study reports that DEPs increased miR-21 expression and then activated the PTEN/PI3K/AKT pathway in human bronchial epithelial (HBE) cells, which may serve as an important carcinogenic mechanism. However, the data revealed that short-term exposure to a high DEP concentration did not cause evident cell carcinogenesis in HBE cells. PMID:25901472

  3. Effect of atmospheric aging on volatility and reactive oxygen species of biodiesel exhaust nano-particles

    NASA Astrophysics Data System (ADS)

    Pourkhesalian, A. M.; Stevanovic, S.; Rahman, M. M.; Faghihi, E. M.; Bottle, S. E.; Masri, A. R.; Brown, R. J.; Ristovski, Z. D.

    2015-08-01

    In the prospect of limited energy resources and climate change, effects of alternative biofuels on primary emissions are being extensively studied. Our two recent studies have shown that biodiesel fuel composition has a significant impact on primary particulate matter emissions. It was also shown that particulate matter caused by biodiesels was substantially different from the emissions due to petroleum diesel. Emissions appeared to have higher oxidative potential with the increase in oxygen content and decrease of carbon chain length and unsaturation levels of fuel molecules. Overall, both studies concluded that chemical composition of biodiesel is more important than its physical properties in controlling exhaust particle emissions. This suggests that the atmospheric aging processes, including secondary organic aerosol formation, of emissions from different fuels will be different as well. In this study, measurements were conducted on a modern common-rail diesel engine. To get more information on realistic properties of tested biodiesel particulate matter once they are released into the atmosphere, particulate matter was exposed to atmospheric oxidants, ozone and ultra-violet light; and the change in their properties was monitored for different biodiesel blends. Upon the exposure to oxidative agents, the chemical composition of the exhaust changes. It triggers the cascade of photochemical reactions resulting in the partitioning of semi-volatile compounds between the gas and particulate phase. In most of the cases, aging lead to the increase in volatility and oxidative potential, and the increment of change was mainly dependent on the chemical composition of fuels as the leading cause for the amount and the type of semi-volatile compounds present in the exhaust.

  4. Effect of atmospheric ageing on volatility and ROS of biodiesel exhaust nano-particles

    NASA Astrophysics Data System (ADS)

    Pourkhesalian, A. M.; Stevanovic, S.; Rahman, M. M.; Faghihi, E. M.; Bottle, S. E.; Masri, A. R.; Brown, R. J.; Ristovski, Z. D.

    2015-03-01

    In the prospect of limited energy resources and climate change, effects of alternative biofuels on primary emissions are being extensively studied. Our two recent studies have shown that biodiesel fuel composition has a~significant impact on primary particulate matter emissions. It was also shown that particulate matter caused by biodiesels was substantially different from the emissions due to petroleum diesel. Emissions appeared to have higher oxidative potential with the increase in oxygen content and decrease of carbon chain length and unsaturation levels of fuel molecules. Overall, both studies concluded that chemical composition of biodiesel is more important than its physical properties in controlling exhaust particle emissions. This suggests that the atmospheric ageing processes, including secondary organic aerosol formation, of emissions from different fuels will be different as well. In this study, measurements were conducted on a modern common-rail diesel engine. To get more information on realistic properties of tested biodiesel particulate matter once they are released into the atmosphere, particulate matter was exposed to atmospheric oxidants, ozone and ultra-violet light; and the change in their properties was monitored for different biodiesel blends. Upon the exposure to oxidative agents, the chemical composition of the exhaust changes. It triggers the cascade of photochemical reactions resulting in the partitioning of semi-volatile compounds between the gas and particulate phase. In most of the cases, aging lead to the increase in volatility and oxidative potential, and the increment of change was mainly dependent on the chemical composition of fuels as the leading cause for the amount and the type of semi-volatile compounds present in the exhaust.

  5. Cytokine expression in mice exposed to diesel exhaust particles by inhalation. Role of tumor necrosis factor

    PubMed Central

    Saber, Anne T; Jacobsen, Nicklas R; Bornholdt, Jette; Kjær, Sanna L; Dybdahl, Marianne; Risom, Lotte; Loft, Steffen; Vogel, Ulla; Wallin, Håkan

    2006-01-01

    Background Particulate air pollution has been associated with lung and cardiovascular disease, for which lung inflammation may be a driving mechanism. The pro-inflammatory cytokine, tumor necrosis factor (TNF) has been suggested to have a key-role in particle-induced inflammation. We studied the time course of gene expression of inflammatory markers in the lungs of wild type mice and Tnf-/- mice after exposure to diesel exhaust particles (DEPs). Mice were exposed to either a single or multiple doses of DEP by inhalation. We measured the mRNA level of the cytokines Tnf and interleukin-6 (Il-6) and the chemokines, monocyte chemoattractant protein (Mcp-1), macrophage inflammatory protein-2 (Mip-2) and keratinocyte derived chemokine (Kc) in the lung tissue at different time points after exposure. Results Tnf mRNA expression levels increased late after DEP-inhalation, whereas the expression levels of Il-6, Mcp-1 and Kc increased early. The expression of Mip-2 was independent of TNF if the dose was above a certain level. The expression levels of the cytokines Kc, Mcp-1 and Il-6, were increased in the absence of TNF. Conclusion Our data demonstrate that Tnf is not important in early DEP induced inflammation and rather exerts negative influence on Mcp-1 and Kc mRNA levels. This suggests that other signalling pathways are important, a candidate being one involving Mcp-1. PMID:16504008

  6. The Impact of Oil Consumption Mechanisms on Diesel Exhaust Particle Size Distributions and Detailed Exhaust Chemical Composition

    SciTech Connect

    Stetter, J; Forster, N; Ghandhi, J; Foster, D

    2003-08-24

    Detailed exhaust emission data have been taken from a Cummins N-14 single cylinder research engine in which the oil consumption was varied by different engine modifications. Low sulfur fuel was used, and oil consumption was varied by modifying the intake valve stem seals, the exhaust valve stem seals, the oil control ring and combinations of these modifications. Detailed measurements of exhaust gas particle size distributions and chemical composition were made for the various oil consumption configurations for a range of engine loads and speeds. The particulate mass was measured with TEOM and traditional gravimetric filter methods. Filter data for EC/OC, sulfates and trace metals have been taken and analyzed. The trace metals in the particulate mass serve as the basis for assessing oil consumption at the different operating conditions. The data indicate that the oil consumption for the steady state testing done here was approximately an order of magnitude below oil consumption values cited in the literature. We did measure changes in the details of the chemical composition of the particulate for the different engine operating conditions, but it did not correlate with changes in the oil consumption. Furthermore, the data indicate that the particle size distribution is not strongly impacted by low level oil consumption variations observed in this work.

  7. Vascular and Cardiac Impairments in Rats Inhaling Ozone and Diesel Exhaust Particles

    PubMed Central

    Kodavanti, Urmila P.; Thomas, Ronald; Ledbetter, Allen D.; Schladweiler, Mette C.; Shannahan, Jonathan H.; Wallenborn, J. Grace; Lund, Amie K.; Campen, Matthew J.; Butler, Elizabeth O.; Gottipolu, Reddy R.; Nyska, Abraham; Richards, Judy E.; Andrews, Deborah; Jaskot, Richard H.; McKee, John; Kotha, Sainath R.; Patel, Rishi B.; Parinandi, Narasimham L.

    2011-01-01

    Background Mechanisms of cardiovascular injuries from exposure to gas and particulate air pollutants are unknown. Objective We sought to determine whether episodic exposure of rats to ozone or diesel exhaust particles (DEP) causes differential cardiovascular impairments that are exacerbated by ozone plus DEP. Methods and results Male Wistar Kyoto rats (10–12 weeks of age) were exposed to air, ozone (0.4 ppm), DEP (2.1 mg/m3), or ozone (0.38 ppm) + DEP (2.2 mg/m3) for 5 hr/day, 1 day/week for 16 weeks, or to air, ozone (0.51 or 1.0 ppm), or DEP (1.9 mg/m3) for 5 hr/day for 2 days. At the end of each exposure period, we examined pulmonary and cardiovascular biomarkers of injury. In the 16-week study, we observed mild pulmonary pathology in the ozone, DEP, and ozone + DEP exposure groups, a slight decrease in circulating lymphocytes in the ozone and DEP groups, and decreased platelets in the DEP group. After 16 weeks of exposure, mRNA biomarkers of oxidative stress (hemeoxygenase-1), thrombosis (tissue factor, plasminogen activator inhibitor-1, tissue plasminogen activator, and von Willebrand factor), vasoconstriction (endothelin-1, endothelin receptors A and B, endothelial NO synthase) and proteolysis [matrix metalloprotease (MMP)-2, MMP-3, and tissue inhibitor of matrix metalloprotease-2] were increased by DEP and/or ozone in the aorta, but not in the heart. Aortic LOX-1 (lectin-like oxidized low-density lipoprotein receptor-1) mRNA and protein increased after ozone exposure, and LOX-1 protein increased after exposure to ozone + DEP. RAGE (receptor for advanced glycation end products) mRNA increased in the ozone + DEP group. Exposure to ozone or DEP depleted cardiac mitochondrial phospholipid fatty acids (DEP > ozone). The combined effect of ozone and DEP exposure was less pronounced than exposure to either pollutant alone. Exposure to ozone or DEP for 2 days (acute) caused mild changes in the aorta. Conclusions In animals exposed to ozone or DEP alone for 16

  8. Impact of Diesel Exhaust Particles on Th2 Response in the Lung in Asthmatic Mice

    PubMed Central

    Inoue, Ken-ichiro; Koike, Eiko; Yanagisawa, Rie; Takano, Hirohisa

    2008-01-01

    Although it has been accepted that pulmonary exposure to diesel exhaust particles (DEP), representative constituents in particulate matter of mass median aerodynamic diameter < or 2.5 µm (PM2.5), exacerbates murine allergic asthma, the in vivo effects of DEP on their cellular events in the context of allergen-specific Th response have never been examined. The aim of this study is to elucidate whether in vivo repetitive exposure to DEP combined with allergen (ovalbumin) facilitate allergen-specific Th response in the lung using a simple ex vivo assay system. As a result, repetitive pulmonary exposure to DEP in vivo, if combined with allergen, amplifies ex vivo allergen-specific Th2 response in the lung compared to that to allergen alone, characterized by high levels of interleukin (IL)-4 and IL-5. The result suggests that in asthmatic subjects, DEP promote Th2-prone milieu in the lung, which additively/synergistically augment asthma pathophysiology in vivo. PMID:19015755

  9. Exposure of mobile chipper operators to diesel exhaust.

    PubMed

    Magagnotti, Natascia; Picchi, Gianni; Sciarra, Gianfranco; Spinelli, Raffaele

    2014-03-01

    The current boom of forest biomass is making mobile chippers increasingly popular among forest operators. This motivates concern about the potential exposure of chipper operators to noxious chemicals derived from diesel fuel combustion. The objective of this study was to determine operator exposure to BTEX (benzene, toluene, ethylbenzene, and xylenes) and polycyclic aromatic hydrocarbons (PAHs) generated from diesel combustion. This study sampled 28 mobile chipping operations in the Italian mountains, in order to determine professional exposure to BTEX and PAHs among chipper operators. IOM, Radiello®, and XAD2 samplers were used for the purpose. Operations were divided into industrial and small scale, the former based on powerful chippers with enclosed cabs and the latter on smaller machines without enclosed cabs. We could not detect any measurable exposure to BTEX, while exposure levels for PAHs were very low, especially for what concerned recognized cancer agents. That is likely related to work environment and organization because mobile chippers work in the open-air forest environment and in the presence of very few other machines. PAH concentration was significantly higher inside cabs than outside. None of the operators involved in this research was exposed to BTEX or PAHs above occupational exposure limits. PMID:24163210

  10. Driver Exposure to Combustion Particles in the U.S. Trucking Industry

    PubMed Central

    Davis, M.E.; Smith, T.J.; Laden, F.; Hart, J.E.; Blicharz, A.P.; Reaser, P.; Garshick, E.

    2008-01-01

    A large study of combustion particle exposures for drivers of diesel-powered trucks was conducted in collaboration with an epidemiologic study of lung cancer outcomes for workers in the trucking industry. Three components of diesel exhaust combustion particles (PM2.5, elemental carbon, and organic carbon) were measured inside the driver cabs of diesel-powered trucks from 36 different trucking terminals across the United States between 2001 and 2005. In-cab particle exposures for drivers assigned to both short and long distance trips were observed, as well as information on the smoking status of the driver, truck characteristics such as age and model, and weather conditions during the sampling session. This article summarizes these findings and describes the relationship between exhaust particles and various determinants of exposure. The results suggest that in-cab particle exposures are positively related to smoking, ambient particle concentrations, truck age, and open windows, with other significant modifying factors such as weather. This study represents the largest and most comprehensive exposure assessment of drivers in the trucking industry, encompassing a 4-year period of observations on diesel and exhaust particle exposures nationwide. The results are relevant not only to the occupational group of truck drivers being examined but also to the general population that live, commute, or work within proximity to diesel-fueled traffic or trucking terminals. PMID:17885912

  11. Generation and characterization of diesel exhaust in a facility for controlled human exposures.

    PubMed

    Sawant, Aniket A; Cocker, David R; Miller, J Wayne; Taliaferro, Tony; Diaz-Sanchez, David; Linn, William S; Clark, Kenneth W; Gong, Henry

    2008-06-01

    An idling medium-duty diesel truck operated on ultralow sulfur diesel fuel was used as an emission source to generate diesel exhaust for controlled human exposure. Repeat tests were conducted on the Federal Test Procedure using a chassis dynamometer to demonstrate the reproducibility of this vehicle as a source of diesel emissions. Exhaust was supplied to a specially constructed exposure chamber at a target concentration of 100 microg x m(-3) diesel particulate matter (DPM). Spatial variability within the chamber was negligible, whereas emission concentrations were stable, reproducible, and similar to concentrations observed on the dynamometer. Measurements of nitric oxide, nitrogen dioxide, carbon monoxide, particulate matter (PM), elemental and organic carbon, carbonyls, trace elements, and polycyclic aromatic hydrocarbons were made during exposures of both healthy and asthmatic volunteers to DPM and control conditions. The effect of the so-called "personal cloud" on total PM mass concentrations was also observed and accounted for. Conventional lung function tests in 11 volunteer subjects (7 stable asthmatic) did not demonstrate a significant change after 2-hr exposures to diesel exhaust. In summary, we demonstrated that this facility can be effectively and safely used to evaluate acute responses to diesel exhaust exposure in human volunteers. PMID:18581813

  12. Autocrine ligands of the epithelial growth factor receptor mediate inflammatory responses to diesel exhaust particles

    PubMed Central

    2014-01-01

    Background Diesel exhaust is associated with cardiovascular and respiratory mortality and morbidity. Acute exposure leads to increased IL-8 expression and airway neutrophilia, however the mechanism of this response is unknown. Objectives: As cigarette smoke-induced IL-8 expression by epithelial cells involves transactivation of the epidermal growth factor receptor (EGFR), we studied the effects of diesel exhaust particles (DEP) on IL-8 release and the role of the EGFR. Methods Primary bronchial epithelial cells (PBEC) were exposed to DEPs or carbon black. IL-8 and EGFR ligand expression (transforming growth factor alpha (TGFα), heparin-binding EGF-like growth factor, and amphiregulin (AR)) were assessed by quantitative RT-PCR and ELISA. Results DEP, but not carbon black, caused a dose-dependent increase in mitogen-activated protein kinase (MAPK) activation and IL-8 expression, however above 50 μg/ml there was an increase in cytotoxicity. At 50 μg/ml, DEPs stimulated transcription and release of IL-8 and EGFR ligands. IL-8 release was blocked by EGFR neutralizing antibodies, an EGFR-selective tyrosine kinase inhibitor and by the metalloprotease inhibitor, GM6001, which blocks EGFR ligand shedding. Neutralizing antibodies to AR, TGFα and heparin-binding (HB)-EGF reduced DEP-induced IL-8 by >50%. Conclusion Expression of IL-8 in response to DEPs is dependent on EGFR activation and that autocrine production of EGFR ligands makes a substantial contribution to this response. Capsule Summary: This study identifies a mechanism whereby diesel particles stimulates IL-8 release from bronchial epithelial cells. This mechanism may help to explain the recruitment of neutrophils into the airways of people exposed to particulate air pollution. PMID:24555532

  13. Test-methods on the test-bench: a comparison of complete exhaust and exhaust particle extracts for genotoxicity/mutagenicity assessment.

    PubMed

    Steiner, Sandro; Heeb, Norbert V; Czerwinski, Jan; Comte, Pierre; Mayer, Andreas; Petri-Fink, Alke; Rothen-Rutishauser, Barbara

    2014-05-01

    With the growing number of new exhaust after-treatment systems, fuels and fuel additives for internal combustion engines, efficient and reliable methods for detecting exhaust genotoxicity and mutagenicity are needed to avoid the widespread application of technologies with undesirable effects toward public health. In a commonly used approach, organic extracts of particulates rather than complete exhaust is used for genotoxicity/mutagenicity assessment, which may reduce the reliability of the results. In the present study, we assessed the mutagenicity and the genotoxicity of complete diesel exhaust compared to an organic exhaust particle extract from the same diesel exhaust in a bacterial and a eukaryotic system, that is, a complex human lung cell model. Both, complete exhaust and organic extract were found to act mutagenic/genotoxic, but the amplitudes of the effects differed considerably. Furthermore, our data indicate that the nature of the mutagenicity may not be identical for complete exhaust and particle extracts. Because in addition, differences between the responses of the different biological systems were found, we suggest that a comprehensive assessment of exhaust toxicity is preferably performed with complete exhaust and with biological systems representative for the organisms and organs of interest (i.e., human lungs) and not only with the Ames test. PMID:24697289

  14. The Diesel Exhaust in Miners Study: IV. Estimating historical exposures to diesel exhaust in underground non-metal mining facilities.

    PubMed

    Vermeulen, Roel; Coble, Joseph B; Lubin, Jay H; Portengen, Lützen; Blair, Aaron; Attfield, Michael D; Silverman, Debra T; Stewart, Patricia A

    2010-10-01

    We developed quantitative estimates of historical exposures to respirable elemental carbon (REC) for an epidemiologic study of mortality, including lung cancer, among diesel-exposed miners at eight non-metal mining facilities [the Diesel Exhaust in Miners Study (DEMS)]. Because there were no historical measurements of diesel exhaust (DE), historical REC (a component of DE) levels were estimated based on REC data from monitoring surveys conducted in 1998-2001 as part of the DEMS investigation. These values were adjusted for underground workers by carbon monoxide (CO) concentration trends in the mines derived from models of historical CO (another DE component) measurements and DE determinants such as engine horsepower (HP; 1 HP = 0.746 kW) and mine ventilation. CO was chosen to estimate historical changes because it was the most frequently measured DE component in our study facilities and it was found to correlate with REC exposure. Databases were constructed by facility and year with air sampling data and with information on the total rate of airflow exhausted from the underground operations in cubic feet per minute (CFM) (1 CFM = 0.0283 m³ min⁻¹), HP of the diesel equipment in use (ADJ HP), and other possible determinants. The ADJ HP purchased after 1990 (ADJ HP₁₉₉₀(+)) was also included to account for lower emissions from newer, cleaner engines. Facility-specific CO levels, relative to those in the DEMS survey year for each year back to the start of dieselization (1947-1967 depending on facility), were predicted based on models of observed CO concentrations and log-transformed (Ln) ADJ HP/CFM and Ln(ADJ HP₁₉₉₀(+)). The resulting temporal trends in relative CO levels were then multiplied by facility/department/job-specific REC estimates derived from the DEMS surveys personal measurements to obtain historical facility/department/job/year-specific REC exposure estimates. The facility-specific temporal trends of CO levels (and thus the REC

  15. Comparative evaluation of the effects of short-term inhalation exposure to diesel engine exhaust on rat lung and brain

    PubMed Central

    van Berlo, Damien; Albrecht, Catrin; Knaapen, Ad M.; Cassee, Flemming R.; Gerlofs-Nijland, Miriam E.; Kooter, Ingeborg M.; Palomero-Gallagher, Nicola; Bidmon, Hans-Jürgen; van Schooten, Frederik-Jan; Krutmann, Jean

    2010-01-01

    Combustion-derived nanoparticles, such as diesel engine exhaust particles, have been implicated in the adverse health effects of particulate air pollution. Recent studies suggest that inhaled nanoparticles may also reach and/or affect the brain. The aim of our study was to comparatively evaluate the effects of short-term diesel engine exhaust (DEE) inhalation exposure on rat brain and lung. After 4 or 18 h recovery from a 2 h nose-only exposure to DEE (1.9 mg/m3), the mRNA expressions of heme oxygenase-1 (HO-1), inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), and cytochrome P450 1A1 (CYP1A1) were investigated in lung as well as in pituitary gland, hypothalamus, olfactory bulb, olfactory tubercles, cerebral cortex, and cerebellum. HO-1 protein expression in brain was investigated by immunohistochemistry and ELISA. In the lung, 4 h post-exposure, CYP1A1 and iNOS mRNA levels were increased, while 18 h post-exposure HO-1 was increased. In the pituitary at 4 h post-exposure, both CYP1A1 and HO-1 were increased; HO-1 was also elevated in the olfactory tuberculum at this time point. At 18 h post-exposure, increased expression of HO-1 and COX-2 was observed in cerebral cortex and cerebellum, respectively. Induction of HO-1 protein was not observed after DEE exposure. Bronchoalveolar lavage analysis of inflammatory cell influx, TNF-α, and IL-6 indicated that the mRNA expression changes occurred in the absence of lung inflammation. Our study shows that a single, short-term inhalation exposure to DEE triggers region-specific gene expression changes in rat brain to an extent comparable to those observed in the lung. PMID:20467864

  16. The Diesel Exhaust in Miners Study: IV. Estimating Historical Exposures to Diesel Exhaust in Underground Non-metal Mining Facilities

    PubMed Central

    Vermeulen, Roel; Coble, Joseph B.; Lubin, Jay H.; Portengen, Lützen; Blair, Aaron; Attfield, Michael D.; Silverman, Debra T.

    2010-01-01

    We developed quantitative estimates of historical exposures to respirable elemental carbon (REC) for an epidemiologic study of mortality, including lung cancer, among diesel-exposed miners at eight non-metal mining facilities [the Diesel Exhaust in Miners Study (DEMS)]. Because there were no historical measurements of diesel exhaust (DE), historical REC (a component of DE) levels were estimated based on REC data from monitoring surveys conducted in 1998–2001 as part of the DEMS investigation. These values were adjusted for underground workers by carbon monoxide (CO) concentration trends in the mines derived from models of historical CO (another DE component) measurements and DE determinants such as engine horsepower (HP; 1 HP = 0.746 kW) and mine ventilation. CO was chosen to estimate historical changes because it was the most frequently measured DE component in our study facilities and it was found to correlate with REC exposure. Databases were constructed by facility and year with air sampling data and with information on the total rate of airflow exhausted from the underground operations in cubic feet per minute (CFM) (1 CFM = 0.0283 m3 min−1), HP of the diesel equipment in use (ADJ HP), and other possible determinants. The ADJ HP purchased after 1990 (ADJ HP1990+) was also included to account for lower emissions from newer, cleaner engines. Facility-specific CO levels, relative to those in the DEMS survey year for each year back to the start of dieselization (1947–1967 depending on facility), were predicted based on models of observed CO concentrations and log-transformed (Ln) ADJ HP/CFM and Ln(ADJ HP1990+). The resulting temporal trends in relative CO levels were then multiplied by facility/department/job-specific REC estimates derived from the DEMS surveys personal measurements to obtain historical facility/department/job/year-specific REC exposure estimates. The facility-specific temporal trends of CO levels (and thus the REC estimates) generated from

  17. ACUTE BEHAVORIAL EFFECTS FROM EXPOSURE TO TWO-STROKE ENGINE EXHAUST

    EPA Science Inventory

    Benefits of changing from two-stroke to four-stroke engines (and other remedial requirements) can be evaluated (monetized) from the standpoint of acute behavioral effects of human exposure to exhaust from these engines. The monetization process depends upon estimates of the magn...

  18. Effects Of Combinations of Ozone and Diesel Exhaust Exposures On Blood, Cardiac, And Lung Endpoints

    EPA Science Inventory

    Human subjects were exposed to combinations of 300 ppb ozone (03) and 300 ug/m3 diesel exhaust (DE) to examine if synergistic effects were observed. Subjects received either filtered air (FA), 03, DE, or DE+03 on Day 1, followed by only 03 exposures on Day 2, and a follow-up on D...

  19. EXPOSURE TO DIESEL EXHAUST ENHANCES THE SEVERITY OF AN ONGOING INFLUENZA INFECTION.

    EPA Science Inventory

    Numerous studies have shown that air pollutants including diesel exhaust (DE), alter host defense responses to decrease resistance to respiratory infection. The purpose of this study was to evaluate the effects of DE exposure on the severity of an ongoing influenza infection in ...

  20. Generation and characterization of diesel exhaust in a facility for controlled human exposures

    EPA Science Inventory

    An idling medium-duty diesel truck operated on ultralow sulfur diesel fuel was used as an emission source to generate diesel exhaust for controlled human exposure. Repeat tests were conducted on the Federal Test Procedure using a chassis dynamometer to demonstrate the reproducibi...

  1. EFFECTS OF CONTROLLED EXPOSURE TO DIESEL EXHAUST IN ALLERGIC ASTHMATIC INDIVIDUALS

    EPA Science Inventory

    After completing a study evaluating the effects of exposure to diesel exhaust (DE) and nitrogen dioxide (NO2) on the lower airways and blood of allergic asthmatic participants, investigators will have measured multiple physiologic and pulmonary function endpoints...

  2. EFFECT OF SHORT TERM DIESEL EXHAUST EXPOSURE ON NASAL RESPONSES TO INFLUENZA IN ALLERGIC RHINITICS.

    EPA Science Inventory

    Introduction: Recently published data suggest that diesel exhaust (DE) has special impact on allergic inflammation, suppressing Th1 and augmenting Th2 responses to allergen via oxidant stress effects on airway cells. Exposures to particulate air pollutants including DE are also a...

  3. Biophysical Assessment of Single Cell Cytotoxicity: Diesel Exhaust Particle-Treated Human Aortic Endothelial Cells

    PubMed Central

    Wu, Yangzhe; Yu, Tian; Gilbertson, Timothy A.; Zhou, Anhong; Xu, Hao; Nguyen, Kytai Truong

    2012-01-01

    Exposure to diesel exhaust particles (DEPs), a major source of traffic-related air pollution, has become a serious health concern due to its adverse influences on human health including cardiovascular and respiratory disorders. To elucidate the relationship between biophysical properties (cell topography, cytoskeleton organizations, and cell mechanics) and functions of endothelial cells exposed to DEPs, atomic force microscope (AFM) was applied to analyze the toxic effects of DEPs on a model cell line from human aortic endothelial cells (HAECs). Fluorescence microscopy and flow cytometry were also applied to further explore DEP-induced cytotoxicity in HAECs. Results revealed that DEPs could negatively impair cell viability and alter membrane nanostructures and cytoskeleton components in a dosage- and a time-dependent manner; and analyses suggested that DEPs-induced hyperpolarization in HAECs appeared in a time-dependent manner, implying DEP treatment would lead to vasodilation, which could be supported by down-regulation of cell biophysical properties (e.g., cell elasticity). These findings are consistent with the conclusion that DEP exposure triggers important biochemical and biophysical changes that would negatively impact the pathological development of cardiovascular diseases. For example, DEP intervention would be one cause of vasodilation, which will expand understanding of biophysical aspects associated with DEP cytotoxicity in HAECs. PMID:22662129

  4. Microarray analysis of the effect of diesel exhaust particles on in vitro cultured macrophages.

    PubMed

    Verheyen, Geert R; Nuijten, Jean-Marie; Van Hummelen, Paul; Schoeters, Greet R

    2004-06-01

    Diesel exhaust particles (DEP) have been reported to induce or aggravate pulmonary diseases, including cancer and asthma. Alveolar macrophages are important cellular targets for DEP and have important immunological and inflammatory properties in the response to foreign substances in the lung. In vitro cultures of human THP-1 cells were differentiated to macrophages and were exposed to 1600 ng/ml DEP during 6 and 24 h. Global changes in gene expression were evaluated using cDNA microarrays containing about 13,000 cDNAs. Each gene on the microarray was present in duplicate. A colorflip experiment was also performed, resulting in four ratio measurements for each gene, that were used to evaluate significance of the gene expression findings. Gene expression changes were very modest (<3-fold induction/repression). Less than 1% of all genes were significantly regulated by DEP. Considering the 6 h exposure data, 50 clones were up- and 39 were downregulated. For the 24 h exposure data, there were 54 upregulated and 60 downregulated genes. Nine genes (CYP1B1, THBD, Il1b, ITGB7, SEC6, TNFRSF1B, LPXN, LOC51093 and BTG2) are upregulated and seven (PRDX1, CD36, PRKACB, BBOX1, CLK1, STMN1, and HMGB2) are downregulated at both time-points. Our data indicate the multitude of biological processes potentially influenced by DEP. PMID:15046786

  5. Health risk assessment for residents exposed to atmospheric diesel exhaust particles in southern region of Taiwan

    NASA Astrophysics Data System (ADS)

    Chio, Chia-Pin; Liao, Chung-Min; Tsai, Ying-I.; Cheng, Man-Ting; Chou, Wei-Chun

    2014-03-01

    Evidence shows a strong association among air pollution, oxidative stress (OS), deoxyribonucleic acid (DNA) damage, and diseases. Recent studies indicated that the aging, human neurodegenerative diseases and cancers resulted from mitochondrial dysfunction and OS. The purpose of this study is to provide a probabilistic risk assessment model to quantify the atmospheric diesel exhaust particles (DEP)-induced pre-cancer biomarker response and cancer incidence risk for residents in south Taiwan. We conducted entirely monthly particulate matter sampling data at five sites in Kaohsiung of south Taiwan in the period 2002-2003. Three findings were found: (i) the DEP dose estimates and cancer risk quantification had heterogeneously spatiotemporal difference in south Taiwan, (ii) the pre-cancer DNA damage biomarker and cancer incidence estimates had a positive yet insignificant association, and (iii) all the estimates of cancer incidence in south Taiwan populations fell within and slight lower than the values from previous cancer epidemiological investigations. In this study, we successfully assessed the tumor incidence for residents posed by DEP exposure in south Taiwan compared with the epidemiological approach. Our approach provides a unique way for assessing human health risk for residences exposed to atmospheric DEP depending on specific combinations of local and regional conditions. Our work implicates the importance of incorporating both environmental and health risk impacts into models of air pollution exposure to guide adaptive mitigation strategies.

  6. Mutagenicity of diesel exhaust particles from an engine with differing exhaust after treatments.

    PubMed

    Shi, X-C; Keane, M J; Ong, T; Li, S-Q; Bugarski, A B

    2010-01-01

    This study was conducted to investigate the effects of engine operating conditions and exhaust aftertreatments on the mutagenicity of diesel particulate matter (DPM) collected directly in an underground mine environment. A number of after-treatment devices are currently used on diesel engines in mines, but it is critical to determine whether reductions in DPM concentrations result in a corresponding decrease in adverse health effects. An eddy-current dynamometer was used to operate naturally aspirated mechanically controlled engine at several steady-state conditions. The samples were collected when the engine was equipped with a standard muffler, a diesel oxidation catalytic converter, two types of uncatalyzed diesel particulate filter systems, and three types of disposable diesel particulate filter elements. Bacterial gene mutation activity of DPM was tested on acetone extracts using the Ames Salmonella assay. The results indicated strong correlation between engine operating conditions and mutagenic activity of DPM. When the engine was fitted with muffler, the mutagenic activity was observed for the samples collected from light-load, but not heavy-load operating conditions. When the engine was equipped with a diesel oxidation catalyst, the samples did not exhibit mutagenic activity for any of four engine operating conditions. Mutagenic activity was observed for the samples collected when the engine was retrofitted with three types of disposable filters and sintered metal diesel particulate filter and operated at light load conditions. However, those filtration systems substantially reduced the concentration-normalized mutagenic activity from the levels observed for the muffler. PMID:20711933

  7. Personal Exposure to Ultrafine Particles and Oxidative DNA Damage

    PubMed Central

    Vinzents, Peter S.; Møller, Peter; Sørensen, Mette; Knudsen, Lisbeth E.; Hertel, Ole; Jensen, Finn Palmgren; Schibye, Bente; Loft, Steffen

    2005-01-01

    Exposure to ultrafine particles (UFPs) from vehicle exhaust has been related to risk of cardiovascular and pulmonary disease and cancer, even though exposure assessment is difficult. We studied personal exposure in terms of number concentrations of UFPs in the breathing zone, using portable instruments in six 18-hr periods in 15 healthy nonsmoking subjects. Exposure contrasts of outdoor pollution were achieved by bicycling in traffic for 5 days and in the laboratory for 1 day. Oxidative DNA damage was assessed as strand breaks and oxidized purines in mononuclear cells isolated from venous blood the morning after exposure measurement. Cumulated outdoor and cumulated indoor exposures to UFPs each were independent significant predictors of the level of purine oxidation in DNA but not of strand breaks. Ambient air concentrations of particulate matter with an aero-dynamic diameter of ≤10 μm (PM10), nitrous oxide, nitrogen dioxide, carbon monoxide, and/or number concentration of UFPs at urban background or busy street monitoring stations was not a significant predictor of DNA damage, although personal UFP exposure was correlated with urban background concentrations of CO and NO2, particularly during bicycling in traffic. The results indicate that biologic effects of UFPs occur at modest exposure, such as that occurring in traffic, which supports the relationship of UFPs and the adverse health effects of air pollution. PMID:16263500

  8. Diesel exhaust particle induction of IL17A contributes to severe asthma

    PubMed Central

    Brandt, Eric B.; Kovacic, Melinda Butsch; Lee, Gerald B.; Gibson, Aaron M.; Acciani, Thomas H.; Le Cras, Timothy D.; Ryan, Patrick H.; Budelsky, Alison L.; Khurana Hershey, Gurjit K.

    2013-01-01

    Background IL-17A has been implicated in severe forms of asthma. However, the factors that promote IL-17A production during the pathogenesis of severe asthma remain undefined. Diesel exhaust particles (DEP) are a major component of traffic related air pollution and are implicated in asthma pathogenesis and exacerbation. Objective To determine the mechanism by which DEP exposure impacts asthma severity using human and mouse studies. Methods Balb/c mice were challenged with DEP +/− house dust mite extract (HDM). Airway inflammation and function, BALF cytokine levels, and flow cytometry of lung T cells were assessed. The impact of DEP exposure on frequency of asthma symptoms and serum cytokine levels was determined in children with allergic asthma. Results In mice, exposure to DEP alone did not induce asthma. DEP and HDM co-exposure markedly enhanced AHR compared to HDM alone and generated a mixed Th2 and Th17 response, including IL-13+IL-17A+ double producing T-cells. IL-17A neutralization prevented DEP-induced exacerbation of AHR. Among 235 high DEP-exposed children with allergic asthma, 32.2% had more frequent asthma symptoms over a 12 month period, compared to only 14.2% in the low DEP-exposed group (p=0.002). Additionally, high DEP-exposed children with allergic asthma had nearly six times higher serum IL-17A levels compared with low DEP-exposed children. Conclusions Expansion of Th17 cells contributes to DEP-mediated exacerbation of allergic asthma. Neutralization of IL-17A may be a useful potential therapeutic strategy to counteract the asthma promoting effects of traffic related air pollution especially in highly exposed severe allergic asthmatics. PMID:24060272

  9. DECREASED PRODUCTION OF SURFACTANT PROTEINS AFTER DIESEL EXHAUST EXPOSURE INCREASES SUSCEPTIBILITY TO INFLUENZA INFECTION

    EPA Science Inventory

    Pulmonary surfactant proteins A and D (SP-A and SP-D), termed collectins, enhance the opsonization of foreign particles and pathogens by phagocytic cells. Inhaled pollutants such as diesel exhaust (DE) have a possible role in suppressing the production of surfactant proteins whic...

  10. Markers of exposure to diesel exhaust in railroad workers. Research report

    SciTech Connect

    Schenker, M.B.; Samuels, S.J.; Kado, N.Y.; Hammond, S.K.; Smith, T.J.

    1990-01-01

    The study measured the exposure of railroad workers to diesel exhaust and environmental tobacco smoke by using personal air samples taken over two consecutive work shifts. Urine samples were collected from 87 subjects at the end of the study work shifts and were analyzed for markers of cigarette smoking (nicotine, cotinine) and for mutagenicity, using a sensitive microsuspension assay (Salmonella strain TA98 with or without S9 enzyme). Among smokers, a dose-response relationship was observed between urinary mutagenicity and the number of cigarettes smoked on the study day. After cigarette smoking was controlled for, no association was present between diesel exhaust exposure and urinary mutagenicity. Among nonsmokers, detectable concentrations of mutagens were present in the urine, but no association could be found between markers of diesel exhaust or environmental tobacco smoke and urinary mutagenicity. It was concluded that the mutagens associated with the levels of exposure to diesel exhaust or environmental tobacco smoke in the study were undetectable in the urine.

  11. Validation of the dynamic direct exposure method for toxicity testing of diesel exhaust in vitro.

    PubMed

    Joeng, Lucky; Hayes, Amanda; Bakand, Shahnaz

    2013-01-01

    Diesel exhaust emission is a major health concern because of the complex nature of its gaseous content (e.g., NO2, NO, CO, and CO2) and high concentration of particulate matter (PM) less than 2.5  μ m which allows for deeper penetration into the human pulmonary system upon inhalation. The aim of this research was to elucidate the potential toxic effects of diesel exhaust on a human pulmonary-based cellular system. Validation of a dynamic direct exposure method for both laboratory (230 hp Volvo truck engine) and field (Volkswagen Passat passenger car) diesel engines, at idle mode, was implemented. Human pulmonary type II epithelial cells (A549) grown on porous membranes were exposed to unmodified diesel exhaust at a low flow rate (37.5 mL/min). In parallel, diesel emission sampling was also conducted using real-time air monitoring techniques. Induced cellular effects were assessed using a range of in vitro cytotoxicity assays (MTS, ATP, and NRU). Reduction of cell viability was observed in a time-dependent manner following 30-60 mins of exposure with NRU as the most sensitive assay. The results suggest that the dynamic direct exposure method has the potential to be implemented for both laboratory- and field-based in vitro toxicity studies of diesel exhaust emissions. PMID:23986878

  12. Validation of the Dynamic Direct Exposure Method for Toxicity Testing of Diesel Exhaust In Vitro

    PubMed Central

    Hayes, Amanda; Bakand, Shahnaz

    2013-01-01

    Diesel exhaust emission is a major health concern because of the complex nature of its gaseous content (e.g., NO2, NO, CO, and CO2) and high concentration of particulate matter (PM) less than 2.5 μm which allows for deeper penetration into the human pulmonary system upon inhalation. The aim of this research was to elucidate the potential toxic effects of diesel exhaust on a human pulmonary-based cellular system. Validation of a dynamic direct exposure method for both laboratory (230 hp Volvo truck engine) and field (Volkswagen Passat passenger car) diesel engines, at idle mode, was implemented. Human pulmonary type II epithelial cells (A549) grown on porous membranes were exposed to unmodified diesel exhaust at a low flow rate (37.5 mL/min). In parallel, diesel emission sampling was also conducted using real-time air monitoring techniques. Induced cellular effects were assessed using a range of in vitro cytotoxicity assays (MTS, ATP, and NRU). Reduction of cell viability was observed in a time-dependent manner following 30–60 mins of exposure with NRU as the most sensitive assay. The results suggest that the dynamic direct exposure method has the potential to be implemented for both laboratory- and field-based in vitro toxicity studies of diesel exhaust emissions. PMID:23986878

  13. Nitrophenols isolated from diesel exhaust particles promote the growth of MCF-7 breast adenocarcinoma cells

    SciTech Connect

    Furuta, Chie; Suzuki, Akira K.; Watanabe, Gen; Li, ChunMei; Taneda, Shinji; Taya, Kazuyoshi

    2008-08-01

    Diesel exhaust particles (DEPs) cause many adverse health problems, and reports indicate increased risk of breast cancer in men and women through exposure to gasoline and vehicle exhaust. However, DEPs include vast numbers of compounds, and the specific compound(s) responsible for these actions are not clear. We recently isolated two nitrophenols from DEPs-3-methyl-4-nitrophenol (4-nitro-m-cresol; PNMC) and 4-nitro-3-phenylphenol (PNMPP)-and showed that they had estrogenic and anti-androgenic activities. Here, we tried to clarify the involvement of these two nitrophenols in promoting the growth of the MCF-7 breast cancer cell line. First, comet assay was used to detect the genotoxicity of PNMC and PNMPP in a CHO cell line. At all doses tested, PNMC and PNMPP showed negative genotoxicity, indicating that they had no tumor initiating activity. Next, the estrogen-responsive breast cancer cell line MCF-7 was used to assess cell proliferation. Proliferation of MCF-7 cells was stimulated by PNMC, PNMPP, and estradiol-17{beta} and the anti-estrogens 4-hydroxytamoxifen and ICI 182,780 inhibited the proliferation. To further investigate transcriptional activity through the estrogen receptor, MCF-7 cells were transfected with a receptor gene that allowed expression of luciferase enzyme under the control of the estrogen regulatory element. PNMC and PNMPP induced luciferase activity in a dose-dependent manner at submicromolar concentrations. ICI 182,780 inhibited the luciferase activity induced by PNMC and PNMPP. These results clearly indicate that PNMC and PNMPP do not show genotoxicity but act as tumor promoters in an estrogen receptor {alpha}-predominant breast cancer cell line.

  14. Suppression of the NF-κB Pathway by Diesel Exhaust Particles Impairs Human Antimycobacterial Immunity

    PubMed Central

    Sarkar, Srijata; Song, Youngmia; Sarkar, Somak; Kipen, Howard M.; Laumbach, Robert J.; Zhang, Junfeng (Jim); Strickland, Pamela A. Ohman; Gardner, Carol R.; Schwander, Stephan

    2012-01-01

    Epidemiological studies suggest that chronic exposure to air pollution increases susceptibility to respiratory infections including tuberculosis in humans. A possible link between particulate air pollutant exposure and antimycobacterial immunity has not been explored in human primary immune cells. We hypothesized that exposure to diesel exhaust particles (DEP), a major component of urban fine particulate matter, suppresses antimycobacterial human immune effector cell functions by modulating TLR-signaling pathways and NF-κB activation. We show that DEP and H37Ra, an avirulent laboratory strain of M.tb, were both taken up by the same peripheral human blood monocytes. To examine the effects of DEP on M.tb-induced production of cytokines, PBMC were stimulated with DEP and M.tb or PPD (purified protein derivative). The production of M.tb and PPD-induced IFN-γ, TNF-α, IL-1β, and IL-6 was reduced in a DEP dose-dependent manner. In contrast, the production of anti-inflammatory IL-10 remained unchanged. Furthermore, DEP stimulation prior to M.tb infection altered the expression of TLR 3, 4, 5, 7 and 10 mRNAs and of a subset of M.tb-induced host genes including inhibition of expression of many NF-κB (e.g. CSF3, IFNG, IFNA, IFNB, IL1A, IL6, NFKBIA) and IRF (e.g. IFNG, IFNA1, IFNB1, CXCL10) pathway target genes. We propose that DEP down-regulate M.tb-induced host gene expression via MyD88-dependent (IL6, IL1A, PTGS2) as well as MyD88-independent (IFNA, IFNB) pathways. Pre-stimulation of PBMC with DEP suppressed the expression of proinflammatory mediators upon M.tb infection inducing a hypo-responsive cellular state. Therefore, DEP alters crucial components of antimycobacterial host immune responses, providing a possible mechanism by which air pollutants alter antimicrobial immunity. PMID:22345648

  15. 4-Nitrophenol, 1-nitropyrene, and 9-nitroanthracene emissions in exhaust particles from diesel vehicles with different exhaust gas treatments

    NASA Astrophysics Data System (ADS)

    Inomata, Satoshi; Fushimi, Akihiro; Sato, Kei; Fujitani, Yuji; Yamada, Hiroyuki

    2015-06-01

    The dependence of nitro-organic compound emissions in automotive exhaust particles on the type of aftertreatment used was investigated. Three diesel vehicles with different aftertreatment systems (an oxidation catalyst, vehicle-DOC; a particulate matter and NOx reduction system, vehicle-DPNR; and a urea-based selective catalytic reduction system, vehicle-SCR) and a gasoline car with a three-way catalyst were tested. Nitro-polycyclic aromatic hydrocarbons (nitro-PAHs) and nitrophenols in the particles emitted were analyzed by thermal desorption gas chromatography/mass spectrometry and liquid chromatography/mass spectrometry. The secondary production of nitro-organic compounds on the filters used to collect particles and the adsorption of gaseous nitro-organic compounds by the filters were evaluated. Emissions of 1-nitropyrene, 9-nitroanthracene, and 4-nitrophenol in the diesel exhaust particles were then quantified. The NOx reduction process in vehicle-DPNR appeared to remove nitro-hydrocarbons efficiently but not to remove nitro-oxygenated hydrocarbons efficiently. The nitro-PAH emission factors were lower for vehicle-DOC when it was not fitted with a catalyst than when it was fitted with a catalyst. The 4-nitrophenol emission factors were also lower for vehicle-DOC with a catalyst than vehicle-DOC without a catalyst, suggesting that the oxidation catalyst was a source of both nitro-PAHs and 4-nitrophenol. The time-resolved aerosol mass spectrometry data suggested that nitro-organic compounds are mainly produced when an engine is working under load. The presence of 4-nitrophenol in the particles was not confirmed statistically because of interference from gaseous 4-nitrophenol. Systematic errors in the estimated amounts of gaseous 1-nitropyrene and 9-nitroanthracene adsorbed onto the filters and the estimated amounts of volatile nitro-organic compounds that evaporated during sampling and during post-sampling conditioning could not be excluded. An analytical method

  16. A source-independent empirical correction procedure for the fast mobility and engine exhaust particle sizers

    NASA Astrophysics Data System (ADS)

    Zimmerman, Naomi; Jeong, Cheol-Heon; Wang, Jonathan M.; Ramos, Manuel; Wallace, James S.; Evans, Greg J.

    2015-01-01

    The TSI Fast Mobility Particle Sizer (FMPS) and Engine Exhaust Particle Sizer (EEPS) provide size distributions for 6-560 nm particles with a time resolution suitable for characterizing transient particle sources; however, the accuracy of these instruments can be source dependent, due to influences of particle morphology. The aim of this study was to develop a source-independent correction protocol for the FMPS and EEPS. The correction protocol consists of: (1) broadening the >80 nm size range of the distribution to account for under-sizing by the FMPS and EEPS; (2) applying an existing correction protocol in the 8-93 nm size range; and (3) dividing each size bin by the ratio of total concentration measured by the FMPS or EEPS and a water-based Condensation Particle Counter (CPC) as a surrogate scaling factor to account for particle morphology. Efficacy of the correction protocol was assessed for three sources: urban ambient air, diluted gasoline direct injection engine exhaust, and diluted diesel engine exhaust. Linear regression against a reference instrument, the Scanning Mobility Particle Sizer (SMPS), before and after applying the correction protocol demonstrated that the correction ensured agreement within 20%.

  17. CULTURE CONDITIONS AFFECT HUMAN AIRWAY EPITHELIAL CELL RESPONSE TO DIESEL PARTICLE EXPOSURE IN VITRO

    EPA Science Inventory

    Diesel exhaust particles (DEP) are a ubiquitous ambient air contaminant that may contribute to the health effects of particulate matter inhalation. In vitro studies have shown that DEP exposure induces pro-inflammatory proteins in human airway epithelial cells (HAEC) with varying...

  18. Particle size distributions in and exhausted from a poultry house

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Here we describe a study looking at the full particulate size range of particles in a poultry house. Agricultural particulates are typically thought of as coarse mode dust. But recent emphasis of PM2.5 regulations on pre-cursors such as ammonia and volatile organic compounds increasingly makes it ne...

  19. Model studies of volatile diesel exhaust particle formation: are organic vapours involved in nucleation and growth?

    NASA Astrophysics Data System (ADS)

    Pirjola, L.; Karl, M.; Rönkkö, T.; Arnold, F.

    2015-09-01

    A high concentration of volatile nucleation mode particles (NUP) formed in the atmosphere when the exhaust cools and dilutes has hazardous health effects and it impairs the visibility in urban areas. Nucleation mechanisms in diesel exhaust are only poorly understood. We performed model studies using two sectional aerosol dynamics process models AEROFOR and MAFOR on the formation of particles in the exhaust of a diesel engine, equipped with an oxidative after-treatment system and running with low fuel sulfur content (FSC) fuel, under laboratory sampling conditions where the dilution system mimics real-world conditions. Different nucleation mechanisms were tested. Based on the measured gaseous sulfuric acid (GSA) and non-volatile core and soot particle number concentrations of the raw exhaust, the model simulations showed that the best agreement between model predictions and measurements in terms of particle number size distribution was obtained by barrier-free heteromolecular homogeneous nucleation between the GSA and a semi-volatile organic vapour combined with the homogeneous nucleation of GSA alone. Major growth of the particles was predicted to occur due to the similar organic vapour at concentrations of (1-2) × 1012 cm-3. The pre-existing core and soot mode concentrations had an opposite trend on the NUP formation, and the maximum NUP formation was predicted if a diesel particle filter (DPF) was used. On the other hand, the model predicted that the NUP formation ceased if the GSA concentration in the raw exhaust was less than 1010 cm-3, which was the case when biofuel was used.

  20. Airborne particle exposure and extrinsic skin aging.

    PubMed

    Vierkötter, Andrea; Schikowski, Tamara; Ranft, Ulrich; Sugiri, Dorothea; Matsui, Mary; Krämer, Ursula; Krutmann, Jean

    2010-12-01

    For decades, extrinsic skin aging has been known to result from chronic exposure to solar radiation and, more recently, to tobacco smoke. In this study, we have assessed the influence of air pollution on skin aging in 400 Caucasian women aged 70-80 years. Skin aging was clinically assessed by means of SCINEXA (score of intrinsic and extrinsic skin aging), a validated skin aging score. Traffic-related exposure at the place of residence was determined by traffic particle emissions and by estimation of soot in fine dust. Exposure to background particle concentration was determined by measurements of ambient particles at fixed monitoring sites. The impact of air pollution on skin aging was analyzed by linear and logistic regression and adjusted for potential confounding variables. Air pollution exposure was significantly correlated to extrinsic skin aging signs, in particular to pigment spots and less pronounced to wrinkles. An increase in soot (per 0.5 × 10(-5) per m) and particles from traffic (per 475  kg per year and square km) was associated with 20% more pigment spots on forehead and cheeks. Background particle pollution, which was measured in low residential areas of the cities without busy traffic and therefore is not directly attributable to traffic but rather to other sources of particles, was also positively correlated to pigment spots on face. These results indicate that particle pollution might influence skin aging as well. PMID:20664556

  1. FACTORS THAT INFLUENCE THE RELATIVE POTENCY OF DIESEL EXHAUST PARTICLES AS ADJUVANTS IN ALLERGIC AIRWAY DISEASE

    EPA Science Inventory

    Description: Studies have shown that diesel exhaust particles (DEP) worsen respiratory diseases including allergic asthma. The adjuvant effects of DEP in the airways have been widely reported; however, the precise determinants and mechanisms of these effects are ill-defined. S...

  2. EFFECTS OF DIESEL EXHAUST PARTICLES ON HUMAN MACROPHAGE RESPONSIVENESS TO LIPOPOLYSACCHARIDE

    EPA Science Inventory

    EFFECTS OF DIESEL EXHAUST PARTICLES ON HUMAN MACROPHAGE RESPONSIVENESS TO LIPOPOLYSACCHARIDE
    S. Mundandhara1 and M.C. Madden2, 1UNC Center for Environmental Medicine, Asthma, and Lung Biology, 2US EPA, NHEERL, Human Studies Division, Chapel Hill, NC, USA

    Epidemiologica...

  3. EFFECTS OF DIESEL EXHAUST PARTICLES ON HUMAN ALVEOLAR MACROPHAGE RESPONSIVENESS TO LIPOPOLYSACCHARIDE

    EPA Science Inventory

    Effects of diesel exhaust particles on human alveolar macrophage responsiveness to lipopolysaccharide
    S. Mundandhara1 , S. Becker2 and M. Madden2, 1UNC Center for Environmental Medicine, Asthma, and Lung Biology, 2US EPA, NHEERL, HSD, Chapel Hill, NC, US

    Epidemiological...

  4. DIESEL EXHAUST PARTICLE INDUCED GENE EXPRESSION CHANGES IN A MURINE MUCOSAL SENSITIZATION MODEL

    EPA Science Inventory

    Studies in humans and animals have shown diesel exhaust particles (DEP) can act as an immunological adjuvant to enhance the development of allergic lung disease and this effect is influenced by the chemical composition of the DEP. The adjuvancy of NIST SRM 2975 (NDEP) generated...

  5. NANOMETER DIESEL EXHAUST PARTICLES ARE NEUROTOXIC TO DOPAMINERGIC NEURONS THROUGH MICROGLIAL ACTIVATION.

    EPA Science Inventory

    NANOMETER DIESEL EXHAUST PARTICLES ARE NEUROTOXIC TO DOPAMINERGIC NEURONS THROUGH MICROGLIAL ACTIVATION. M.L. Block1,2, X. Wu1, P. Zhong1, G. Li1, T. Wang1, J.S. Hong1 & B.Veronesi.2
    1The Laboratory of Pharmacology and Chemistry, NIEHS, RTP, NC and 2 National Health and Envi...

  6. SAMPLE CHARACTERIZATION OF AUTOMOBILE AND FORKLIFT DIESEL EXHAUST PARTICLES AND COMPARATIVE PULMONARY TOXICITY IN MICE

    EPA Science Inventory


    Abstract

    Two samples of diesel exhaust particles (DEP) predominate in DEP health effects research: an automobile-source DEP (A-DEP) sample and the National Institute of Standards Technology (NIST) standard reference material (SRM 2975) generated from a forklift engine...

  7. BIOASSAY-DIRECTED FRACTIONAL AND SALMONELLA MUTAGENICITY OF AUTOMOBILE AND FORKLIFT DIESEL EXHAUST PARTICLES

    EPA Science Inventory



    Abstract

    Many pulmonary toxicity studies of diesel exhaust particles (DEP) have used an
    automobile-generated sample (A-DEP) whose mutagenicity has not been reported. In contrast,
    rnany inutagenicity studies of DEP have used a forklift-generated sample (SRM ...

  8. EFFECT OF DIESEL EXHAUST PARTICLES ON HUMAN NASAL LAVAGE CELLS AND DNA ADDUCTS

    EPA Science Inventory

    The overall aim of this study is to determine (using a nasal challenge model) the effect of diesel exhaust particles (DEP) on nasal responses including induction of inflammation, immune changes and DNA damage. We are also examining how treatment of DEP with ozone (oz-DEP)modify ...

  9. DIESEL EXHAUST PARTICLE COMPOSITION AND THE METHOD OF SONICATION INFLUENCE THE ADJUVANCY EFFECT AND TARC PRODUCTION

    EPA Science Inventory

    Numerous reports have shown diesel exhaust particles (DEP) can act as an immunological adjuvant in asthma. Recent interest has focused on thymus and activation-regulated chemokine (TARC) as an important modulator of this effect. This study evaluated the adjuvancy effects of thr...

  10. Anti-androgenic activity of 3-methyl-4-nitrophenol in diesel exhaust particles.

    PubMed

    Li, ChunMei; Taneda, Shinji; Suzuki, Akira K; Furuta, Chie; Watanabe, Gen; Taya, Kazuyoshi

    2006-08-14

    In our continuing studies on nitrophenol derivatives as vasodilators in diesel exhaust particles, we have reported that nitrophenols in diesel exhaust particles possess not only vasodilatory activity but also estrogenic activity in vitro and in vivo, as well as anti-androgenic activity in vitro. Our efforts here were focused on the in vitro and in vivo anti-androgenic activity of 3-methyl-4-nitrophenol (4-nitro-m-cresol; PNMC), known a degradation product of the insecticide fenitrothion, in diesel exhaust particles. We investigated its anti-androgenic activity using an in vitro recombinant yeast screen and in vivo Hershberger assays. Recombinant yeast screen assay showed that PNMC possesses anti-androgenic activity at low concentrations. Furthermore, castrated 28-day-old immature male rats each implanted with a 5-mm-long silastic tube containing crystalline testosterone and injected with PNMC subcutaneously at doses from as low as 0.01 and 0.1 mg/kg up to 1 mg/kg for 5 consecutive days showed significantly decreased weights of the seminal vesicles, ventral prostate, and glans penis. Plasma follicle-stimulating hormone (FSH) and luteinizing hormone (LH) levels were significantly increased in the 0.1 mg/kg PNMC treatment group. Our results demonstrate that PNMC in diesel exhaust particles clearly has anti-androgenic activity both in vitro and in vivo and can therefore be considered as an endocrine-disrupting chemical. PMID:16822498

  11. Eugenol attenuates pulmonary damage induced by diesel exhaust particles.

    PubMed

    Zin, Walter A; Silva, Ana G L S; Magalhães, Clarissa B; Carvalho, Giovanna M C; Riva, Douglas R; Lima, Crystianne C; Leal-Cardoso, Jose H; Takiya, Christina M; Valença, Samuel S; Saldiva, Paulo H N; Faffe, Débora S

    2012-03-01

    Environmentally relevant doses of inhaled diesel particles elicit pulmonary inflammation and impair lung mechanics. Eugenol, a methoxyphenol component of clove oil, presents in vitro and in vivo anti-inflammatory and antioxidant properties. Our aim was to examine a possible protective role of eugenol against lung injuries induced by diesel particles. Male BALB/c mice were divided into four groups. Mice received saline (10 μl in; CTRL group) or 15 μg of diesel particles DEP (15 μg in; DIE and DEUG groups). After 1 h, mice received saline (10 μl; CTRL and DIE groups) or eugenol (164 mg/kg; EUG and DEUG group) by gavage. Twenty-four hours after gavage, pulmonary resistive (ΔP1), viscoelastic (ΔP2) and total (ΔPtot) pressures, static elastance (Est), and viscoelastic component of elastance (ΔE) were measured. We also determined the fraction areas of normal and collapsed alveoli, amounts of polymorpho- (PMN) and mononuclear cells in lung parenchyma, apoptosis, and oxidative stress. Est, ΔP2, ΔPtot, and ΔE were significantly higher in the DIE than in the other groups. DIE also showed significantly more PMN, airspace collapse, and apoptosis than the other groups. However, no beneficial effect on lipid peroxidation was observed in DEUG group. In conclusion, eugenol avoided changes in lung mechanics, pulmonary inflammation, and alveolar collapse elicited by diesel particles. It attenuated the activation signal of caspase-3 by DEP, but apoptosis evaluated by TUNEL was avoided. Finally, it could not avoid oxidative stress as indicated by malondialdehyde. PMID:22194320

  12. Numerical study of particle deposition and scaling in dust exhaust of cyclone separator

    NASA Astrophysics Data System (ADS)

    Xu, W. W.; Li, Q.; Zhao, Y. L.; Wang, J. J.; Jin, Y. H.

    2016-05-01

    The solid particles accumulation in the dust exhaust cone area of the cyclone separator can cause the wall wear. This undoubtedly prevents the flue gas turbine from long period and safe operation. So it is important to study the mechanism how the particles deposited and scale on dust exhaust cone area of the cyclone separator. Numerical simulations of gas-solid flow field have been carried out in a single tube in the third cyclone separator. The three-dimensionally coupled computational fluid dynamic (CFD) technology and the modified Discrete Phase Model (DPM) are adopted to model the gas-solid two-phase flow. The results show that with the increase of the operating temperature and processing capacity, the particle sticking possibility near the cone area will rise. The sticking rates will decrease when the particle diameter becomes bigger.

  13. Case-control study of diesel exhaust exposure and bladder cancer

    SciTech Connect

    Wynder, E.L.; Dieck, G.S.; Hall, N.E.L.; Lahti, H.

    1985-08-01

    The relationship between bladder cancer and employment in occupations involving exposure to diesel exhaust was examined using data from a hospital-based case-control study of men aged 20 to 80 years in 18 hospitals in six US cities, from January 1981 to May 1983. In this analysis, 194 cases and 582 controls were compared according to occupation, smoking history, alcohol and coffee consumption, and various demographic variables. No difference was found in the proportion of bladder cancer cases employed in occupations with exposure to diesel exhaust compared to controls. This relationship did not change after taking smoking habits into account. Bladder cancer cases were significantly more likely to be current smokers of cigarettes than were controls.

  14. Tracking the pathway of diesel exhaust particles from the nose to the brain by X-ray florescence analysis

    NASA Astrophysics Data System (ADS)

    Matsui, Yasuto; Sakai, Nobumitsu; Tsuda, Akira; Terada, Yasuko; Takaoka, Masaki; Fujimaki, Hidekazu; Uchiyama, Iwao

    2009-08-01

    Studies have shown that exposure to nano-sized particles (< 50 nm) result in their translocation to the central nervous system through the olfactory nerve. Translocation commonly occurs via inhalation, ingestion and skin uptake. Little information is available on the specific pathway of cellular localization of nano-sized particles in the olfactory bulb. The nano-sized particles entrance into the postsynaptics cell is of particular interest because the mitral cell projects to the central nucleus of the amygdala and the piriform cortex. Therefore, our objective in this follow-up study has been to determine whether or not the mitral cells project nano-sized particles to the brain. Nano-sized particles in this study were generated using diesel exhaust. Lab mice were exposed for a period of 4 weeks. We employed synchrotron radiation (SPring-8, Japan) to determine the concentration levels of metal in the olfactory neuron pathway. Metal levels were assayed by mapping, using X-ray fluorescence analysis. The major metal components measured in the filter that collected the inhaled diesel exhaust particles were calcium, copper, iron, nickel and zinc. Our studies reveal an increase in the amount of nano-sized particles in the glomerular layer as well as in the neurons in the olfactory epithelium. Higher levels of nickel and iron were found in the olfactory epithelium's lamina propria mucosae in comparison to that in the control group. Higher levels of iron also were observed in the glomerular layer. Our studies do not clarify the specifics of metal adhesion and detachment. This remains to be one of the key issues requiring further clarification.

  15. Diesel exhaust particles modulate vascular endothelial cell permeability: Implication of ZO-1 Expression

    PubMed Central

    Li, Rongsong; Ning, Zhi; Cui, Jeffrey; Yu, Fei; Sioutas, Constantinos; Hsiai, Tzung

    2010-01-01

    Exposure to air pollutants increases the incidence of cardiovascular disease. Recent toxicity studies revealed that ultra fine particles (UFP, dp<100–200 nm), the major portion of particulate matter (PM) by numbers in the atmosphere, induced atherosclerosis. In this study, we posited that variations in chemical composition in diesel exhausted particles (DEP) regulated endothelial cell permeability to a different extent. Human aortic endothelial cells (HAEC) were exposed to well-characterized DEP (dp<100 nm) emitted from a diesel engine in either idling mode (DEP1) or in urban dynamometer driving schedule (UDDS) (DEP2). Horse Radish Peroxidase-Streptavidin activity assay showed that DEP2 increased endothelial permeability to a greater extent than DEP1 (Control=0.077± 0.005, DEP1=0.175±0.003, DEP2=0.265±0.006, n=3, p<0.01). DEP2 also down-regulated tight junction protein, Zonular Occludin-1 (ZO-1), to a greater extent compared to DEP1. LDH and caspase-3 activities revealed that DEP-mediated increase in permeability was not due to direct cytotoxicity, and DEP-mediated ZO-1 down-regulation was not due to a decrease in ZO-1 mRNA. Hence, our findings suggest that DEP1 versus DEP2 differentially influenced the extent of endothelial permeability at the post-translational level. This increase in endothelium permeability is implicated in inflammatory cell transmigration into subendothelial layers with relevance to the initiation of atherosclerosis. PMID:20576493

  16. Reducing Children's Exposure to School Bus Diesel Exhaust in One School District in North Carolina

    ERIC Educational Resources Information Center

    Mazer, Mary E.; Jacobson Vann, Julie C.; Lamanna, Beth F.; Davison, Jean

    2014-01-01

    Children who are exposed to diesel exhaust from idling school buses are at increased risk of asthma exacerbation, decreased lung function, immunologic reactions, leukemia, and increased susceptibility to infections. Policies and initiatives that aim to protect school children from the harmful effects of exposure to diesel exhaust range from…

  17. Modeling Particle Exposure in US Trucking Terminals

    PubMed Central

    Davis, ME; Smith, TJ; Laden, F; Hart, JE; Ryan, LM; Garshick, E

    2007-01-01

    Multi-tiered sampling approaches are common in environmental and occupational exposure assessment, where exposures for a given individual are often modeled based on simultaneous measurements taken at multiple indoor and outdoor sites. The monitoring data from such studies is hierarchical by design, imposing a complex covariance structure that must be accounted for in order to obtain unbiased estimates of exposure. Statistical methods such as structural equation modeling (SEM) represent a useful alternative to simple linear regression in these cases, providing simultaneous and unbiased predictions of each level of exposure based on a set of covariates specific to the exposure setting. We test the SEM approach using data from a large exposure assessment of diesel and combustion particles in the US trucking industry. The exposure assessment includes data from 36 different trucking terminals across the United States sampled between 2001 and 2005, measuring PM2.5 and its elemental carbon (EC), organic carbon (OC) components, by personal monitoring, and sampling at two indoor work locations and an outdoor “background” location. Using the SEM method, we predict: 1) personal exposures as a function of work related exposure and smoking status; 2) work related exposure as a function of terminal characteristics, indoor ventilation, job location, and background exposure conditions; and 3) background exposure conditions as a function of weather, nearby source pollution, and other regional differences across terminal sites. The primary advantage of SEMs in this setting is the ability to simultaneously predict exposures at each of the sampling locations, while accounting for the complex covariance structure among the measurements and descriptive variables. The statistically significant results and high R2 values observed from the trucking industry application supports the broader use of this approach in exposure assessment modeling. PMID:16856739

  18. Controlled Exposure to Diesel Exhaust Causes Increased Nitrite in Exhaled Breath Condensate among Subjects with Asthma

    PubMed Central

    Hussain, Sabiha; Laumbach, Robert; Coleman, Jakemia; Youseff, Hatim; Kelly-McNeil, Kathie; Ohman-Strickland, Pamela; Zhang, Junfeng; Kipen, Howard

    2015-01-01

    Objective We aimed to determine if oxidative/nitrosative stress plays a role in the acute effects of diesel exhaust (DE) on asthmatics. Methods Crossover study design, 16 subjects with mild to moderate asthma were exposed to clean filtered air (CA) or diluted DE (300µg/m3 as PM2.5) for 1 hour with intermittent exercise. Results Airway hyperreactivity increased 24 hrs after exposure to DE as compared to CA (PC20 14.9 mg/ml vs. 19.7 mg/ml, p=0.012). Nitrite in EBC was elevated immediately after diesel exposure (p=0.052), and remained elevated 4 and 24 hrs after exposure. Conclusions After exposure to DE, subjects with asthma demonstrated increased airway hyperreactivity and obstruction. Increased nitrite in EBC, in the absence of increased eNO, suggests a non-inflammatory oxidative stress mechanism by which DE affects the lung. PMID:23001278

  19. Diesel Exhaust Exposure and the Risk of Lung Cancer—A Review of the Epidemiological Evidence

    PubMed Central

    Sun, Yi; Bochmann, Frank; Nold, Annette; Mattenklott, Markus

    2014-01-01

    To critically evaluate the association between diesel exhaust (DE) exposure and the risk of lung cancer, we conducted a systematic review of published epidemiological evidences. To comprehensively identify original studies on the association between DE exposure and the risk of lung cancer, literature searches were performed in literature databases for the period between 1970 and 2013, including bibliographies and cross-referencing. In total, 42 cohort studies and 32 case-control studies were identified in which the association between DE exposures and lung cancer was examined. In general, previous studies suffer from a series of methodological limitations, including design, exposure assessment methods and statistical analysis used. A lack of objective exposure information appears to be the main problem in interpreting epidemiological evidence. To facilitate the interpretation and comparison of previous studies, a job-exposure matrix (JEM) of DE exposures was created based on around 4,000 historical industrial measurements. The values from the JEM were considered during interpretation and comparison of previous studies. Overall, neither cohort nor case-control studies indicate a clear exposure-response relationship between DE exposure and lung cancer. Epidemiological studies published to date do not allow a valid quantification of the association between DE and lung cancer. PMID:24473109

  20. Examination of cytokines and metals in exhaled breath condensate and lung lavage fluids after diesel exhaust exposure

    EPA Science Inventory

    Epidemiology studies link human exposure to ambient air pollution with the development and exacerbation of cardiopulmonary disease. Diesel exhaust (DE) is a significant source of ambient air pollution, and thus may contribute to adverse pulmonary health effects. Previous human re...

  1. Inflammatory Cytokines and White Blood Cell Counts Response to Environmental Levels of Diesel Exhaust and Ozone Inhalation Exposures

    EPA Science Inventory

    Epidemiological observations of urban inhalation exposures to diesel exhaust (DE) and ozone (O3) have shown pre-clinical cardiopulmonary responses in humans. Identifying the key biological mechanisms that initiate these health bioindicators is difficult due to variability in envi...

  2. Diesel exhaust particles induce the over expression of tumor necrosis factor-alpha (TNF-alpha) gene in alvelor machrophage and failed to induce apoptosis through activation of nuclear factor-kappaB (NF-kappaB)

    EPA Science Inventory

    Exposure to particulate matter (PM2.5-10), including diesel exhaust particles (DEP) has been reported to induce lung injury and exacerbation of asthma and chronic obstructive pulmonary disease. Alveolar macrophages play a major role in the lung's response to inhaled particles and...

  3. Chemical and physical properties of ultrafine diesel exhaust particles sampled downstream of a catalytic trap.

    PubMed

    Grose, Melissa; Sakurai, Hiromu; Savstrom, Jake; Stolzenburg, Mark R; Watts, Winthrop F; Morgan, Christopher G; Murray, Ian P; Twigg, Martyn V; Kittelson, David B; McMurry, Peter H

    2006-09-01

    The chemical and physical properties of exhaust particles produced by a Caterpillar 3176 C-12 heavy duty diesel engine equipped with a catalytic trap (CRT) are reported. The engine was operated at 600 Nm and 1500 rpm, using fuels containing 15 and 49 ppm sulfur. A two-stage dilution tunnel designed to simulate the reactions that occur when hot combustion products mix with cooler atmospheric air was used. Particle size distributions were measured using a scanning mobility particle sizer (SMPS) and nano-scanning mobility particle sizer (nano SMPS); a nanomicro-orifice uniform deposit impactor (nano MOUDI) collected size-resolved samples for gravimetric and chemical analysis. A nanometer tandem differential mobility analyzer (nano TDMA) was used to measure the volatility and hygroscopicity of 4-15 nm particles. These measurements confirm that the particles consisted primarily of sulfates. PMID:16999131

  4. Organic and inorganic fractions of diesel exhaust particles produce changes in mucin profile of mouse trachea explants.

    PubMed

    Seriani, Robson; Junqueira, Mara S; Toledo, Alessandra C; Corrêa, Aristides T; Silva, Luiz F F; Martins, Milton A; Saldiva, Paulo H N; Mauad, Thais; Macchione, Mariângela

    2015-01-01

    Diesel exhaust particles (DEP) contain organic and inorganic elements that produce damage to the respiratory epithelium. The aim of this study was to determine the mucus profile of tracheal explants exposed to either crude diesel exhaust particles (DEP) or DEP treated with nitric acid (DEP/NA), with hexane (DEP/HEX), or with methanol (DEP/MET) at concentrations of 50 and 100 μg/ml for 30 and 60 min. Tracheal explants were subjected to morphometric analyses to study acidic (AB+), neutral (PAS+), and mixed (AB+/PAS+) mucus production and vacuolization (V). Incubation with 50 μg/ml crude DEP resulted in a rise in acid mucus production, an increase in vacuolization at 30 min, and reduction in neutral mucus at 30 and 60 min. Tracheas exposed to DEP/MET at 50 μg/ml for 30 or 60 min resulted in a significant decrease in neutral mucus production and an elevation in acid mucus production. DEP/HEX increased vacuolization at both 50 and 100 μg/ml at 30 and 60 min of exposure. Treatment with 50 μg/ml for 30 or 60 min significantly elevated mixed mucus levels. These results suggest that DEP appear to be more toxic when administered in combination with HEX or MET. DEP/MET modified the mucus profile of the epithelium, while DEP/HEX altered mucus extrusion, and these responses might be due to bioavailability of individual elements in DEP fractions. PMID:25674825

  5. The efficacy of local exhaust ventilation for controlling dust exposures during concrete surface grinding.

    PubMed

    Croteau, Gerry A; Flanagan, Mary Ellen; Camp, Janice E; Seixas, Noah S

    2004-08-01

    This study assessed the effectiveness of a commercially available local exhaust ventilation (LEV) system for controlling respirable dust and crystalline silica exposures during concrete grinding activities. Surface grinding was conducted at six commercial building construction sites in Seattle, WA, by cement masons. Time-integrated filter samples and direct reading respirable dust concentrations were collected using a cyclone in line with a direct reading respirable dust monitor. Personal exposure levels were determined with and without LEV, one sample directly after the other. A total of 28 paired samples were collected in which three different dust collection shroud configurations were tested. Data obtained with a direct reading respirable dust monitor were adjusted to remove non-work task-associated dust exposures and was subsequently used to calculate the exposure reduction achieved. The application of LEV resulted in a reduction in the overall geometric mean respirable dust exposure from 4.5 to 0.14 mg/m(3), a mean exposure reduction of 92%. Despite the effective control of dust generated during surface grinding, 22 and 26% of the samples collected while LEV was being used were greater than the 8 h time-weighted average permissible exposure limit (Occupational Safety and Health Administration) and threshold limit value (American Congress of Governmental Industrial Hygienists) for respirable crystalline silica, respectively. PMID:15298850

  6. The diesel exhaust in miners study: I. Overview of the exposure assessment process.

    PubMed

    Stewart, Patricia A; Coble, Joseph B; Vermeulen, Roel; Schleiff, Patricia; Blair, Aaron; Lubin, Jay; Attfield, Michael; Silverman, Debra T

    2010-10-01

    This report provides an overview of the exposure assessment process for an epidemiologic study that investigated mortality, with a special focus on lung cancer, associated with diesel exhaust (DE) exposure among miners. Details of several components are provided in four other reports. A major challenge for this study was the development of quantitative estimates of historical exposures to DE. There is no single standard method for assessing the totality of DE, so respirable elemental carbon (REC), a component of DE, was selected as the primary surrogate in this study. Air monitoring surveys at seven of the eight study mining facilities were conducted between 1998 and 2001 and provided reference personal REC exposure levels and measurements for other agents and DE components in the mining environment. (The eighth facility had closed permanently prior to the surveys.) Exposure estimates were developed for mining facility/department/job/year combinations. A hierarchical grouping strategy was developed for assigning exposure levels to underground jobs [based on job titles, on the amount of time spent in various areas of the underground mine, and on similar carbon monoxide (CO, another DE component) concentrations] and to surface jobs (based on the use of, or proximity to, diesel-powered equipment). Time trends in air concentrations for underground jobs were estimated from mining facility-specific prediction models using diesel equipment horsepower, total air flow rates exhausted from the underground mines, and, because there were no historical REC measurements, historical measurements of CO. Exposures to potentially confounding agents, i.e. respirable dust, silica, radon, asbestos, and non-diesel sources of polycyclic aromatic hydrocarbons, also were assessed. Accuracy and reliability of the estimated REC exposures levels were evaluated by comparison with several smaller datasets and by development of alternative time trend models. During 1998-2001, the average

  7. The Diesel Exhaust in Miners Study: I. Overview of the Exposure Assessment Process

    PubMed Central

    Stewart, Patricia A.; Coble, Joseph B.; Vermeulen, Roel; Schleiff, Patricia; Blair, Aaron; Lubin, Jay; Attfield, Michael; Silverman, Debra T.

    2010-01-01

    This report provides an overview of the exposure assessment process for an epidemiologic study that investigated mortality, with a special focus on lung cancer, associated with diesel exhaust (DE) exposure among miners. Details of several components are provided in four other reports. A major challenge for this study was the development of quantitative estimates of historical exposures to DE. There is no single standard method for assessing the totality of DE, so respirable elemental carbon (REC), a component of DE, was selected as the primary surrogate in this study. Air monitoring surveys at seven of the eight study mining facilities were conducted between 1998 and 2001 and provided reference personal REC exposure levels and measurements for other agents and DE components in the mining environment. (The eighth facility had closed permanently prior to the surveys.) Exposure estimates were developed for mining facility/department/job/year combinations. A hierarchical grouping strategy was developed for assigning exposure levels to underground jobs [based on job titles, on the amount of time spent in various areas of the underground mine, and on similar carbon monoxide (CO, another DE component) concentrations] and to surface jobs (based on the use of, or proximity to, diesel-powered equipment). Time trends in air concentrations for underground jobs were estimated from mining facility-specific prediction models using diesel equipment horsepower, total air flow rates exhausted from the underground mines, and, because there were no historical REC measurements, historical measurements of CO. Exposures to potentially confounding agents, i.e. respirable dust, silica, radon, asbestos, and non-diesel sources of polycyclic aromatic hydrocarbons, also were assessed. Accuracy and reliability of the estimated REC exposures levels were evaluated by comparison with several smaller datasets and by development of alternative time trend models. During 1998–2001, the average

  8. Designing, construction, assessment, and efficiency of local exhaust ventilation in controlling crystalline silica dust and particles, and formaldehyde in a foundry industry plant.

    PubMed

    Morteza, Mortezavi Mehrizi; Hossein, Kakooi; Amirhossein, Matin; Naser, Hasheminegad; Gholamhossein, Halvani; Hossein, Fallah

    2013-01-01

    The purpose of the present study was to design and assess the efficiency of a local exhaust ventilation system used in a foundry operation to control inhalable dust and particles, microcrystal particles, and noxious gases and vapours affecting workers during the foundry process. It was designed based on recommendations from the American Conference of Governmental Industrial Hygiene. After designing a local exhaust ventilation system (LEV), we prepared and submitted the implementation plan to the manufacturer. High concentrations of crystalline silica dust and formaldehyde, which are common toxic air pollutants in foundries, were ultimately measured as an indicator for studying the efficiency of this system in controlling inhalable dust and particles as well as other air pollutants. The level of occupational exposure to silica and formaldehyde as major air pollutants was assessed in two modes: first, when the LEV was on, and second, when it was off. Air samples from the exposure area were obtained using a personal sampling pump and analysed using the No. 7601 method for crystal silica and the No. 2541 method for formaldehyde of the National Institute for Occupational Safety and Health (NIOSH). Silica and formaldehyde concentrations were determined by visible absorption spectrophotometry and gas chromatography. The results showed that local exhaust ventilation was successful in preserving the crystal silica particles in the work environment at a level below the NIOSH maximum allowed concentration (0.05 mg m-3). In contrast, formaldehyde exceeded the NIOSH limit (1 ppm or 1.228 mg m-3). PMID:23585164

  9. MUTAGENICITY OF DIESEL-EXHAUST PARTICLE EXTRACTS COLLECTED UNDER SMOG-CHAMBER CONDITIONS USING THE 'SALMONELLA TYPHIMURIUM' TEST SYSTEM

    EPA Science Inventory

    The study was designed to detect the effect that different environmental conditions have upon diesel-exhaust organics. In this study, diesel-exhaust was injected into the Calspan smog chamber under different conditions, and the resulting particles were collected upon Pallflex gla...

  10. Ice-nucleating particle emissions from photochemically aged diesel and biodiesel exhaust

    NASA Astrophysics Data System (ADS)

    Schill, G. P.; Jathar, S. H.; Kodros, J. K.; Levin, E. J. T.; Galang, A. M.; Friedman, B.; Link, M. F.; Farmer, D. K.; Pierce, J. R.; Kreidenweis, S. M.; DeMott, P. J.

    2016-05-01

    Immersion-mode ice-nucleating particle (INP) concentrations from an off-road diesel engine were measured using a continuous-flow diffusion chamber at -30°C. Both petrodiesel and biodiesel were utilized, and the exhaust was aged up to 1.5 photochemically equivalent days using an oxidative flow reactor. We found that aged and unaged diesel exhaust of both fuels is not likely to contribute to atmospheric INP concentrations at mixed-phase cloud conditions. To explore this further, a new limit-of-detection parameterization for ice nucleation on diesel exhaust was developed. Using a global-chemical transport model, potential black carbon INP (INPBC) concentrations were determined using a current literature INPBC parameterization and the limit-of-detection parameterization. Model outputs indicate that the current literature parameterization likely overemphasizes INPBC concentrations, especially in the Northern Hemisphere. These results highlight the need to integrate new INPBC parameterizations into global climate models as generalized INPBC parameterizations are not valid for diesel exhaust.

  11. Capture Efficiency of Cooking-Related Fine and Ultrafine Particles by Residential Exhaust Hoods

    SciTech Connect

    Lunden, Melissa M.; Delp, William W.

    2014-06-05

    Effective exhaust hoods can mitigate the indoor air quality impacts of pollutant emissions from residential cooking. This study reports capture efficiencies (CE) measured for cooking generated particles for scripted cooking procedures in a 121-m3 chamber with kitchenette. CEs also were measured for burner produced CO2 during cooking and separately for pots and pans containing water. The study used four exhaust hoods previously tested by Delp and Singer (Environ. Sci. Technol., 2012, 46, 6167-6173). For pan-frying a hamburger over medium heat on the back burner, CEs for particles were similar to those for burner produced CO2 and mostly above 80percent. For stir-frying green beans in a wok (high heat, front burner), CEs for burner CO2 during cooking varied by hood and airflow: CEs were 34-38percent for low (51?68 L s-1) and 54?72percent for high (109?138 L s-1) settings. CEs for 0.3?2.0 ?m particles during front burner stir-frying were 3?11percent on low and 16?70percent on high settings. Results indicate that CEs measured for burner CO2 are not predictive of CEs of cooking-generated particles under all conditions, but they may be suitable to identify devices with CEs above 80percent both for burner combustion products and for cooking-related particles.

  12. The effect of local exhaust ventilation controls on dust exposures during concrete cutting and grinding activities.

    PubMed

    Croteau, Gerry A; Guffey, Steven E; Flanagan, Mary Ellen; Seixas, Noah S

    2002-01-01

    This study assessed the effectiveness of commercially available local exhaust ventilation (LEV) systems for controlling respirable dust and crystalline silica exposures during concrete cutting and grinding activities. Work activities were performed by union-sponsored apprentices and included tuck-point grinding, surface grinding, paver block and brick cutting (masonry saw), and concrete block cutting (hand-held saw). In a randomized block design, implemented under controlled field conditions, three ventilation rates (0, 30, and 75 cfm) were tested for each tool. Each ventilation treatment was replicated three times in random order for a total of nine 15-min work sessions per study subject. With the exception of the hand-held saw, the use of LEV resulted in a significant (p < 0.05) reduction in respirable dust exposure. Mean exposure levels for the 75 cfm treatments were less than that of the 30 cfm treatments; however, differences between these two treatments were only significant for paver block cutting (p < 0.01). Although exposure reduction was significant (70-90% at the low ventilation rate and 80-95% reduction at the high ventilation rate), personal respirable dust [corrected] exposures remained very high: 1.4-2.8 x PEL (permissible exposure limit) at the low ventilation rate and 0.9-1.7 x PEL at the high ventilation rate. Exposure levels found under actual field conditions would likely be lower due to the intermittent nature of most job tasks. Despite incomplete control LEV has merit, as it would reduce the risk of workers developing disease, allow workers to use a lower level of respiratory protection, protect workers during short duration work episodes reduce exposure to nearby workers, and reduce clean-up associated dust exposures. PMID:12486779

  13. Exposure history of individual cosmic particles

    NASA Technical Reports Server (NTRS)

    Nishiizumi, K.; Arnold, J. R.; Fink, D.; Klein, J.; Middleton, R.

    1991-01-01

    Cosmogenic Be-10 and Al-26 were measured in a suite of stony cosmic spherules derived from deep-sea sediments and the Greenland ice cap. These spherules show clear evidence of exposure to galactic cosmic ray and solar cosmic ray bombardment on time scales from a few times 100,000 years up to as much as 10 to the 7th years. The exposure took place in the inner solar system, not in highly eccentric orbits. When they reached the earth, the particles were not much larger than their present size, but it is not excluded that most of their cosmic ray exposure took place very close to the surface of an asteroidal body.

  14. The characterisation of diesel exhaust particles - composition, size distribution and partitioning.

    PubMed

    Alam, Mohammed S; Zeraati-Rezaei, Soheil; Stark, Christopher P; Liang, Zhirong; Xu, Hongming; Harrison, Roy M

    2016-07-18

    A number of major research questions remain concerning the sources and properties of road traffic generated particulate matter. A full understanding of the composition of primary vehicle exhaust aerosol and its contribution to secondary organic aerosol (SOA) formation still remains elusive, and many uncertainties exist relating to the semi-volatile component of the particles. Semi-Volatile Organic Compounds (SVOCs) are compounds which partition directly between the gas and aerosol phases under ambient conditions. The SVOCs in engine exhaust are typically hydrocarbons in the C15-C35 range, and are largely uncharacterised because they are unresolved by traditional gas chromatography, forming a large hump in the chromatogram referred to as Unresolved Complex Mixture (UCM). In this study, thermal desorption coupled to comprehensive Two Dimensional Gas-Chromatography Time-of-Flight Mass-Spectrometry (TD-GC × GC-ToF-MS) was exploited to characterise and quantify the composition of SVOCs from the exhaust emission. Samples were collected from the exhaust of a diesel engine, sampling before and after a diesel oxidation catalyst (DOC), while testing at steady state conditions. Engine exhaust was diluted with air and collected using both filter and impaction (nano-MOUDI), to resolve total mass and size resolved mass respectively. Adsorption tubes were utilised to collect SVOCs in the gas phase and they were then analysed using thermal desorption, while particle size distribution was evaluated by sampling with a DMS500. The SVOCs were observed to contain predominantly n-alkanes, branched alkanes, alkyl-cycloalkanes, alkyl-benzenes, PAHs and various cyclic aromatics. Particle phase compounds identified were similar to those observed in engine lubricants, while vapour phase constituents were similar to those measured in fuels. Preliminary results are presented illustrating differences in the particle size distribution and SVOCs composition when collecting samples with and

  15. Biological activity of particle exhaust emissions from light-duty diesel engines.

    PubMed

    Carraro, E; Locatelli, A L; Ferrero, C; Fea, E; Gilli, G

    1997-01-01

    Whole diesel exhaust has been classified recently as a probable carcinogen, and several genotoxicity studies have found particulate exhaust to be clearly mutagenic. Moreover, genotoxicity of diesel particulate is greatly influenced by fuel nature and type of combustion. In order to obtain an effective environmental pollution control, combustion processes using alternative fuels are being analyzed presently. The goal of this study is to determine whether the installation of exhaust after treatment-devices on two light-duty, exhaust gas recirculation (EGR) valve-equipped diesel engines (1930 cc and 2500 cc) can reduce the mutagenicity associated with particles collected during U.S.A. and European driving cycles. Another interesting object was to compare the ability of alternative biodiesel and conventional diesel fuels to reduce the mutagenic activity associated with collected particles from two light duty diesel engines (both 1930 cc) during the European driving cycle. SOF mutagenicity was assayed using the Salmonella/microsome test (TA 98 and TA 100 strains, +/- S9 fraction). In the first part of our study, the highest mutagenicity was revealed by TA98 strain without enzymatic activation, suggesting a direct-acting mutagenicity prevalence in diesel particulate. The 2500 cc engine revealed twofold mutagenic activity compared with the 1930 cc engine (both EGR valve equipped), whereas an opposite result was found in particulate matter amount. The use of a noncatalytic ceramic trap produced a decrease of particle mutagenic activity in the 2500 cc car, whereas an enhancement in the 1930 cc engine was found. The catalytic converter and the electrostatic filter installed on the 2500 cc engine yielded a light particle amount and an SOF mutagenicity decrease. A greater engine stress was obtained using European driving cycles, which caused the strongest mutagenicity/km compared with the U.S.A. cycles. In the second part of the investigation, even though a small number of

  16. Particle-Bound PAH Emission from the Exhaust of Combustion Chamber

    NASA Astrophysics Data System (ADS)

    Asgari Lamjiri, M.; Medrano, Y. S.; Guillaume, D. W.; Khachikian, C. S.

    2013-12-01

    Polycyclic Aromatic Hydrocarbons (PAHs) are harmful, semi-volatile organic compounds which are generated due to the incomplete combustion of organic substances. PAHs are of concern as a pollutant because some of these compounds are carcinogenic and mutagenic even at low levels. Most of the PAHs are recalcitrant and persistent in the environment. The PAHs carcinogenic potential can be increased by the adsorption onto small size particles (< 1μm) which can easily get into the bronchioles and alveoli of the lungs. PAHs associated with sub-micron particles are mostly generated from high temperature sources like combustion chambers. In this current study, the presence of 16 priority PAHs (listed by United States Environmental Protection Agency) which are attached to the particulates emitted from the exhaust of the jet engine are evaluated. The engine was operated at different swirl numbers (S; the ratio of tangential air flow to axial air flow) to investigate the effect of this parameter on the effluent of combustion chamber. The samples were collected using two instruments simultaneously: a particle analyzer and a Micro-Orifice Uniform Deposited Impactor (MOUDI). Particle analyzer was used to count the number of particles in different sizes and MOUDI was used to collect particles with respect to their size as they were emitted from the exhaust. The MOUDI's aluminum substrates were weighed before and after the experiment in order to measure the mass of particles that were collected during the sampling period. The concentration of PAHs associated with the particles was measured by extracting the particles with dichloromethane followed by analysis via gas chromatography/mass spectrometry (GC/MS). In general, lower molecular weight PAHs emitted from the exhaust of combustion chamber are mostly in gas phase while PAHs of higher molecular weight are adsorbed onto particles. Preliminary results from GC/MS confirm the presence of higher molecular weight PAHs like Benzo

  17. Effect of diesel exhaust particles on allergic reactions and airway responsiveness in ovalbumin-sensitized brown Norway rats.

    PubMed

    Dong, Caroline C; Yin, Xuejun J; Ma, Jane Y C; Millecchia, Lyndell; Wu, Zhong-Xin; Barger, Mark W; Roberts, Jenny R; Antonini, James M; Dey, Richard D; Ma, Joseph K H

    2005-11-01

    We have previously demonstrated that exposure to diesel exhaust particles (DEP) prior to ovalbumin (OVA) sensitization in rats reduced OVA-induced airway inflammation. In the present study, Brown Norway rats were first sensitized to OVA (42.3 +/- 5.7 mg/m3) for 30 min on days 1, 8, and 15, then exposed to filtered air or DEP (22.7 +/- 2.5 mg/m3) for 4 h/day on days 24-28, and challenged with OVA on day 29. Airway responsiveness was examined on day 30, and animals were sacrificed on day 31. Ovalbumin sensitization and challenge resulted in a significant infiltration of neutrophils, lymphocytes, and eosinophils into the lung, elevated presence of CD4+ and CD8+ T lymphocytes in lung draining lymph nodes, and increased production of serum OVA-specific immunoglobulin (Ig)E and IgG. Diesel exhaust particles pre-exposure augmented OVA-induced production of allergen-specific IgE and IgG and pulmonary inflammation characterized by marked increases in T lymphocytes and infiltration of eosinophils after OVA challenge, whereas DEP alone did not have these effects. Although OVA-sensitized rats showed modest response to methacholine challenge, it was the combined DEP and OVA exposure that produced significant airway hyperresponsiveness in this animal model. The effect of DEP pre-exposure on OVA-induced immune responses correlated with an interactive effect of DEP with OVA on increased production of reactive oxygen species (ROS) and nitric oxide (NO) by alveolar macrophages (AM) and alveolar type II (ATII) cells, NO levels in bronchoalveolar lavage fluid, the induction of inducible NO synthase expression in AM and ATII cells, and a depletion of total intracellular glutathione (GSH) in AM and lymphocytes. These results show that DEP pre-exposure exacerbates the allergic responses to the subsequent challenge with OVA in OVA-sensitized rats. This DEP effect may be, at least partially, attributed to the elevated generation of ROS in AM and ATII cells, a depletion of GSH in AM and

  18. Chemical characterization of freshly emitted particulate matter from aircraft exhaust using single particle mass spectrometry

    NASA Astrophysics Data System (ADS)

    Abegglen, Manuel; Brem, B. T.; Ellenrieder, M.; Durdina, L.; Rindlisbacher, T.; Wang, J.; Lohmann, U.; Sierau, B.

    2016-06-01

    Non-volatile aircraft engine emissions are an important anthropogenic source of soot particles in the upper troposphere and in the vicinity of airports. They influence climate and contribute to global warming. In addition, they impact air quality and thus human health and the environment. The chemical composition of non-volatile particulate matter emission from aircraft engines was investigated using single particle time-of-flight mass spectrometry. The exhaust from three different aircraft engines was sampled and analyzed. The soot particulate matter was sampled directly behind the turbine in a test cell at Zurich Airport. Single particle analyses will focus on metallic compounds. The particles analyzed herein represent a subset of the emissions composed of the largest particles with a mobility diameter >100 nm due to instrumental restrictions. A vast majority of the analyzed particles was shown to contain elemental carbon, and depending on the engine and the applied thrust the elemental carbon to total carbon ratio ranged from 83% to 99%. The detected metallic compounds were all internally mixed with the soot particles. The most abundant metals in the exhaust were Cr, Fe, Mo, Na, Ca and Al; V, Ba, Co, Cu, Ni, Pb, Mg, Mn, Si, Ti and Zr were also detected. We further investigated potential sources of the ATOFMS-detected metallic compounds using Inductively Coupled Plasma Mass Spectrometry. The potential sources considered were kerosene, engine lubrication oil and abrasion from engine wearing components. An unambiguous source apportionment was not possible because most metallic compounds were detected in several of the analyzed sources.

  19. CONTROLLED EXPOSURES OF HUMAN VOLUNTEERS TO DIESEL ENGINE EXHAUST: BIOMARKERS OF EXPOSURE AND HEALTH OUTCOMES

    EPA Science Inventory

    Combustion of diesel fuel contributes to ambient air pollutant fine particulate matter (PM) and gases. Fine PM exposure has been associated with increased mortality due to adverse cardiac events, and morbidity, such as increased hospitalization for asthma symptoms and lung infect...

  20. Differential transcriptional regulation of IL-8 expression by human airway epithelial cells exposed to diesel exhaust particles

    SciTech Connect

    Tal, Tamara L.; Simmons, Steven O.; Silbajoris, Robert; Dailey, Lisa; Cho, Seung-Hyun; Ramabhadran, Ram; Linak, William; Reed, William; Bromberg, Philip A.; Samet, James M.

    2010-02-15

    Exposure to diesel exhaust particles (DEP) induces inflammatory signaling characterized by MAP kinase-mediated activation of NFkB and AP-1 in vitro and in bronchial biopsies obtained from human subjects exposed to DEP. NFkB and AP-1 activation results in the upregulation of genes involved in promoting inflammation in airway epithelial cells, a principal target of inhaled DEP. IL-8 is a proinflammatory chemokine expressed by the airway epithelium in response to environmental pollutants. The mechanism by which DEP exposure induces IL-8 expression is not well understood. In the current study, we sought to determine whether DEP with varying organic content induces IL-8 expression in lung epithelial cells, as well as, to develop a method to rapidly evaluate the upstream mechanism(s) by which DEP induces IL-8 expression. Exposure to DEP with varying organic content differentially induced IL-8 expression and IL-8 promoter activity human airway epithelial cells. Mutational analysis of the IL-8 promoter was also performed using recombinant human cell lines expressing reporters linked to the mutated promoters. Treatment with a low organic-containing DEP stimulated IL-8 expression by a mechanism that is predominantly NFkB-dependent. In contrast, exposure to high organic-containing DEP induced IL-8 expression independently of NFkB through a mechanism that requires AP-1 activity. Our study reveals that exposure to DEP of varying organic content induces proinflammatory gene expression through multiple specific mechanisms in human airway epithelial cells. The approaches used in the present study demonstrate the utility of a promoter-reporter assay ensemble for identifying transcriptional pathways activated by pollutant exposure.

  1. Regulation of Human Hepatic Drug Transporter Activity and Expression by Diesel Exhaust Particle Extract

    PubMed Central

    Le Vee, Marc; Jouan, Elodie; Stieger, Bruno; Lecureur, Valérie; Fardel, Olivier

    2015-01-01

    Diesel exhaust particles (DEPs) are common environmental air pollutants primarily affecting the lung. DEPs or chemicals adsorbed on DEPs also exert extra-pulmonary effects, including alteration of hepatic drug detoxifying enzyme expression. The present study was designed to determine whether organic DEP extract (DEPe) may target hepatic drug transporters that contribute in a major way to drug detoxification. Using primary human hepatocytes and transporter-overexpressing cells, DEPe was first shown to strongly inhibit activities of the sinusoidal solute carrier (SLC) uptake transporters organic anion-transporting polypeptides (OATP) 1B1, 1B3 and 2B1 and of the canalicular ATP-binding cassette (ABC) efflux pump multidrug resistance-associated protein 2, with IC50 values ranging from approximately 1 to 20 μg/mL and relevant to environmental exposure situations. By contrast, 25 μg/mL DEPe failed to alter activities of the SLC transporter organic cation transporter (OCT) 1 and of the ABC efflux pumps P-glycoprotein and bile salt export pump (BSEP), whereas it only moderately inhibited those of sodium taurocholate co-transporting polypeptide and of breast cancer resistance protein (BCRP). Treatment by 25 μg/mL DEPe was next demonstrated to induce expression of BCRP at both mRNA and protein level in cultured human hepatic cells, whereas it concomitantly repressed mRNA expression of various transporters, including OATP1B3, OATP2B1, OCT1 and BSEP. Such changes in transporter expression were found to be highly correlated to those caused by 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), a reference activator of the aryl hydrocarbon receptor (AhR) pathway. This suggests that DEPe, which is enriched in known ligands of AhR like polycyclic aromatic hydrocarbons, alters drug transporter expression via activation of the AhR cascade. Taken together, these data established human hepatic transporters as targets of organic chemicals containing in DEPs, which may contribute to their

  2. Regulation of human hepatic drug transporter activity and expression by diesel exhaust particle extract.

    PubMed

    Le Vee, Marc; Jouan, Elodie; Stieger, Bruno; Lecureur, Valérie; Fardel, Olivier

    2015-01-01

    Diesel exhaust particles (DEPs) are common environmental air pollutants primarily affecting the lung. DEPs or chemicals adsorbed on DEPs also exert extra-pulmonary effects, including alteration of hepatic drug detoxifying enzyme expression. The present study was designed to determine whether organic DEP extract (DEPe) may target hepatic drug transporters that contribute in a major way to drug detoxification. Using primary human hepatocytes and transporter-overexpressing cells, DEPe was first shown to strongly inhibit activities of the sinusoidal solute carrier (SLC) uptake transporters organic anion-transporting polypeptides (OATP) 1B1, 1B3 and 2B1 and of the canalicular ATP-binding cassette (ABC) efflux pump multidrug resistance-associated protein 2, with IC50 values ranging from approximately 1 to 20 μg/mL and relevant to environmental exposure situations. By contrast, 25 μg/mL DEPe failed to alter activities of the SLC transporter organic cation transporter (OCT) 1 and of the ABC efflux pumps P-glycoprotein and bile salt export pump (BSEP), whereas it only moderately inhibited those of sodium taurocholate co-transporting polypeptide and of breast cancer resistance protein (BCRP). Treatment by 25 μg/mL DEPe was next demonstrated to induce expression of BCRP at both mRNA and protein level in cultured human hepatic cells, whereas it concomitantly repressed mRNA expression of various transporters, including OATP1B3, OATP2B1, OCT1 and BSEP. Such changes in transporter expression were found to be highly correlated to those caused by 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), a reference activator of the aryl hydrocarbon receptor (AhR) pathway. This suggests that DEPe, which is enriched in known ligands of AhR like polycyclic aromatic hydrocarbons, alters drug transporter expression via activation of the AhR cascade. Taken together, these data established human hepatic transporters as targets of organic chemicals containing in DEPs, which may contribute to their

  3. New method for time-resolved diesel engine exhaust particle mass measurement.

    PubMed

    Lehmann, U; Niemelä, V; Mohr, M

    2004-11-01

    The Dekati mass monitor (DMM; Dekati Ltd., Finland), a relatively new real-time mass measurement instrument, was investigated in this project. In contrast to the existing gravimetric filter method also used as a standard for regulation purposes, this instrument provides second-by-second data on mass concentration in the engine exhaust gas. The principle of the DMM is based on particle charging, inertial and electrical size classification, and electrical detection of aerosol particles. This study focuses on the instrument's practical performance. Details on calibration and the theory of operation will be published elsewhere. The exhaust emissions of two heavy-duty engines complying with the Euro III emission standard were measured on a dynamic engine test bench. We looked atthe particle number and mass emissions of the engines in different transient test cycles and steady-state conditions. The ability to follow transient test cycles and the response times of the DMM were investigated. The aerosol mass concentration measured by the DMM was compared with the mass concentration obtained by the standard gravimetric filter method with Teflon-coated glass fiber filters. The total mass concentration (integral over the whole cycle) measured by the DMM is about 20% higher than that measured by the standard gravimetric filter method. The total mass concentration from the DMM was also compared with the volume concentration calculated from the electrical low-pressure impactor (ELPI) measurements. Correlations were made with other particle measuring systems. The DMM correlates very well with the particulate mass (R2 = 0.95) and exhibits good linearity and repeatability. The response time to a well-defined change in exhaust concentration was observed to be fast and stable. The DMM was able to follow transient test cycles and provides good results on a second-by-second basis. The instrument used in this study was still under development, and there is therefore no complete

  4. Controlled human exposures to ambient pollutant particles in susceptible populations

    EPA Science Inventory

    Epidemiologic studies have established an association between exposures to air pollution particles and human mortality and morbidity at concentrations of particles currently found in major metropolitan areas. The adverse effects of pollution particles are most prominent in suscep...

  5. ROLE OF NEPRILYSIN IN AIRWAY INFLAMMATION INDUCED BY DIESEL EXHAUST EMISSIONS

    EPA Science Inventory

    The investigators intend to evaluate airway inflammatory responses and expression of the enzyme neprilysin in response to diesel exhaust particle exposure. Dr. Wong and colleagues anticipate that their research will reveal that components of diesel exhaust decrease neprilys...

  6. Measurements of Br/Pb Ratios in Airborne Particles from Car Exhaust

    NASA Astrophysics Data System (ADS)

    Öblad, M.; Selin, E.

    1985-10-01

    Concentrations of particulate bromine and lead have been measured during one summer and one winter period. The measurements were made simultaneously in five sites in a city on the Swedish west coast. A rural site about 60 km from the city was used to measure the background aerosol. Aerosol sampling was made with six dichotomous virtual impactors, which fractionate the aerosol into two modes, one fine particle mode (aerodynamic diameter, a.d. < 3.5 μm) and one coarse particle mode (3.5 μm < a.d. < 18 μm). The aerosol was collected onto thin teflon filters. Element concentrations were obtained by Energy Dispersive X-Ray Fluorescence Analysis. The element concentrations were related to air mass trajectories. The Br/Pb ratio proved to be the same on a given date for the city sites and the background site. A dependence on the air mass history was found, suggesting that it is the quality of the air basin in the region that influences the Br/Pb ratio even for fresh car exhaust. The Br/Pb ratio was the same for fine and coarse particles, indicating that the ratio is determined before coagulation with larger particles occur. The ratios between coarse and fine particles containing lead and bromine respectively were also studied. The results suggest that lead and bromine are actually attached to the same particles.

  7. The Diesel Exhaust in Miners Study: V. Evaluation of the Exposure Assessment Methods.

    PubMed

    Stewart, Patricia A; Vermeulen, Roel; Coble, Joseph B; Blair, Aaron; Schleiff, Patricia; Lubin, Jay H; Attfield, Mike; Silverman, Debra T

    2012-03-01

    Exposure to respirable elemental carbon (REC), a component of diesel exhaust (DE), was assessed for an epidemiologic study investigating the association between DE and mortality, particularly from lung cancer, among miners at eight mining facilities from the date of dieselization (1947-1967) through 1997. To provide insight into the quality of the estimates for use in the epidemiologic analyses, several approaches were taken to evaluate the exposure assessment process and the quality of the estimates. An analysis of variance was conducted to evaluate the variability of 1998-2001 REC measurements within and between exposure groups of underground jobs. Estimates for the surface exposure groups were evaluated to determine if the arithmetic means (AMs) of the REC measurements increased with increased proximity to, or use of, diesel-powered equipment, which was the basis on which the surface groups were formed. Estimates of carbon monoxide (CO) (another component of DE) air concentrations in 1976-1977, derived from models developed to predict estimated historical exposures, were compared to 1976-1977 CO measurement data that had not been used in the model development. Alternative sets of estimates were developed to investigate the robustness of various model assumptions. These estimates were based on prediction models using: (i) REC medians rather AMs, (ii) a different CO:REC proportionality than a 1:1 relation, and (iii) 5-year averages of historical CO measurements rather than modeled historical CO measurements and DE-related determinants. The analysis of variance found that in three of the facilities, most of the between-group variability in the underground measurements was explained by the use of job titles. There was relatively little between-group variability in the other facilities. The estimated REC AMs for the surface exposure groups rose overall from 1 to 5 μg m(-3) as proximity to, and use of, diesel equipment increased. The alternative estimates overall

  8. Analysis of mid-tropospheric Space Shuttle exhausted aluminum oxide particles

    NASA Technical Reports Server (NTRS)

    Cofer, Wesley R., III; Lala, G. Garland; Wightman, James P.

    1987-01-01

    Aluminum oxide particles from the exhaust of the Space Shuttle were collected immediately after the launch of the SEPEX mission and during the descent over the altitude interval of 7.6-4.6 km. The SEM examination revealed that the particles were spherical and ranged in diameter from about 0.1 micron to 10 microns. Results from the energy dispersive analysis (by an X-ray method) and of the particle chemistry (by electron spectroscopy) confirmed that the particles were predominantly composed of aluminum and oxygen. The particle size distribution of the Al2O3 was bimodal, with one observed peak centered near 2.0 microns; the other distribution mode centered at a diameter of less than 0.3 micron, but could not be accurately located. A mass median diameter was slightly less than 2 microns. Evaluation of ice nucleation activity revealed only a small fraction (about 1 ppm) of active ice nuclei among the Al2O3 particulates.

  9. Extracellular glutamate level and NMDA receptor subunit expression in mouse olfactory bulb following nanoparticle-rich diesel exhaust exposure.

    PubMed

    Win-Shwe, Tin-Tin; Mitsushima, Dai; Yamamoto, Shoji; Fujitani, Yuji; Funabashi, Toshiya; Hirano, Seishiro; Fujimaki, Hidekazu

    2009-08-01

    In this present study, we aimed to investigate the extracellular glutamate level and memory function-related gene expression in the mouse olfactory bulb after exposure of the animals to nanoparticle-rich diesel exhaust (NRDE) with or without bacterial cell wall component. Lipoteichoic acid (LTA), a cell wall component derived from Staphylococcus aureus, was used to induce systemic inflammation. Male BALB/c mice were exposed to clean air (particle concentration, 4.58 microg/m(3)) or NRDE (148.86 microg/m(3)) 5 h per day on 5 consecutive days of the week for 4 wk with or without weekly intraperitoneal injection of LTA. We examined the extracellular glutamate levels in the olfactory bulb using in vivo microdialysis and high-performance liquid chromatography assay. Then, we collected the olfactory bulb to examine the expression of N-methyl-D-aspartate (NMDA) receptor subunits (NR1, NR2A, and NR2B) and calcium/calmodulin-dependent protein kinase (CaMK) IV and cyclic AMP response element binding protein (CREB)-1 using real-time reverse-transcription polymerase chain reaction (RT-PCR). NRDE and/or LTA caused significantly increased extracellular glutamate levels in the olfactory bulb of mice. Moreover, the exposure of mice to NRDE upregulates NR1, NR2A, NR2B, and CaMKIV mRNAs in the olfactory bulb, while LTA upregulates only NR2B and CREB1 mRNAs. These findings suggest that NRDE and LTA cause glutamate-induced neurotoxicity separately and accompanied by changes in the expression of NMDA receptor subunits and related kinase and transcription factor in the mouse olfactory bulb. This is the first study to show the correlation between glutamate toxicity and memory function-related gene expressions in the mouse olfactory bulb following exposure to NRDE. PMID:19653804

  10. Toronto Residents' Exposure to Ultrafine Particles

    NASA Astrophysics Data System (ADS)

    Sabaliauskas, Kelly Maria

    In urban areas, ultrafine particles (UFP: defined as particulate matter with diameters less than 100nm) are emitted in significant quantities from vehicles and form through a complex series of secondary reactions in the atmosphere. Large uncertainties surrounding the long-term behaviour and spatial distribution of UFP in urban areas have been a significant obstacle for exposure assessment. This research examined one of the longest existing urban UFP data sets, collected at a roadside location in downtown Toronto. Between 2006 and 2011, the concentration of particles with diameters <50nm and 50-100nm decreased by 21% and 17%, respectively. This reduction in concentration was attributed to changes in the vehicle fleet and reduced usage of coal-fired power plants for electricity generation. In addition, this research found that the shape of the particle size distribution exhibited distinct temporal and spatial behaviour suggesting that a single monitoring station does not provide sufficient information about UFP for an entire urban area. This investigation also produced a land-use regression model that was used to estimate the range of concentrations that exist across Toronto during the summer months. The highest concentrations were consistently observed near the downtown core and around highways and industrial areas. Finally, this work provides a foundation for future field studies in Toronto.

  11. Exposure to diesel exhaust upregulates COX-2 expression in ApoE knockout mice

    PubMed Central

    Bai, Ni; Tranfield, Erin M.; Kavanagh, Terrance J.; Kaufman, Joel D.; Rosenfeld, Michael E.; van Eeden, Stephan F.

    2015-01-01

    Introduction We have shown that diesel exhaust (DE) inhalation caused progression of atherosclerosis; however, the mechanisms are not fully understood. We hypothesize that exposure to DE upregulates cyclooxygenase (COX) expression and activity, which could play a role in DE-induced atherosclerosis. Methods ApoE knockout mice (30-week old) fed with regular chow were exposed to DE (at 200 μg/m3 of particulate matter) or filtered air (control) for 7 weeks (6 h/day, 5 days/week). The protein and mRNA expression of COX-1 and COX-2 were evaluated by immunohistochemistry analysis and quantitative real-time PCR, respectively. To examine COX activity, thoracic aortae were mounted in a wire myograph, and phenylephrine (PE)-stimulated vasoconstriction was measured with and without the presence of COX antagonists (indomethacin). COX-2 activity was further assessed by urine 2,3-dinor-6-keto PGF1α level, a major metabolite of prostacyclin I2 (PGI2). Results Immunohistochemistry analysis demonstrates that DE exposure enhanced COX-2 expression in both thoracic aorta (p < 0.01) and aortic root (p < 0.03), with no modification of COX-1 expression. The increased COX-2 expression was positively correlated with smooth muscle cell content in aortic lesions (R2 = 0.4081, p < 0.008). The fractional changes of maximal vasoconstriction in the presence of indomethacin was attenuated by 3-fold after DE exposure (p < 0.02). Urine 2,3-dinor-6-keto PGF1α level was 15-fold higher in DE group than the control (p < 0.007). The mRNA expression of COX-2 (p < 0.006) and PGI synthase (p < 0.02), but not COX-1, was significantly augmented after DE exposure. Conclusion We show that DE inhalation enhanced COX-2 expression, which is also associated with phenotypic changes of aortic lesion. PMID:22746401

  12. Exposure to particles from laser printers operating within office workplaces.

    PubMed

    McGarry, Peter; Morawska, Lidia; He, Congrong; Jayaratne, Rohan; Falk, Matthew; Tran, Quang; Wang, Hao

    2011-08-01

    While recent research has provided valuable information as to the composition of laser printer particles, their formation mechanisms, and explained why some printers are emitters while others are low emitters, questions relating to the potential exposure of office workers remained unanswered. In particular, (i) what impact does the operation of laser printers have on the background particle number concentration (PNC) of an office environment over the duration of a typical working day? (ii) What is the airborne particle exposure to office workers in the vicinity of laser printers? (iii) What influence does the office ventilation have upon the transport and concentration of particles? (iv) Is there a need to control the generation of, and/or transport of particles arising from the operation of laser printers within an office environment? (v) What instrumentation and methodology is relevant for characterizing such particles within an office location? We present experimental evidence on printer temporal and spatial PNC during the operation of 107 laser printers within open plan offices of five buildings. The 8 h time-weighted average printer particle exposure is significantly less than the 8 h time-weighted local background particle exposure, but that peak printer particle exposure can be greater than 2 orders of magnitude higher than local background particle exposure. The particle size range is predominantly ultrafine (<100 nm diameter). In addition we have established that office workers are constantly exposed to nonprinter derived particle concentrations, with up to an order of magnitude difference in such exposure among offices, and propose that such exposure be controlled along with exposure to printer derived particles. We also propose, for the first time, that peak particle reference values be calculated for each office area analogous to the criteria used in Australia and elsewhere for evaluating exposure excursion above occupational hazardous chemical exposure

  13. Occupational Exposure to Diesel Motor Exhaust and Lung Cancer: A Dose-Response Relationship Hidden by Asbestos Exposure Adjustment? The ICARE Study.

    PubMed

    Matrat, Mireille; Guida, Florence; Cénée, Sylvie; Févotte, Joelle; Carton, Matthieu; Cyr, Diane; Menvielle, Gwenn; Paget-Bailly, Sophie; Radoï, Loredana; Schmaus, Annie; Bara, Simona; Velten, Michel; Luce, Danièle; Stücker, Isabelle; The Icare Study Group

    2015-01-01

    Background. In a French large population-based case-control study we investigated the dose-response relationship between lung cancer and occupational exposure to diesel motor exhaust (DME), taking into account asbestos exposure. Methods. Exposure to DME was assessed by questionnaire. Asbestos was taken into account through a global indicator of exposure to occupational carcinogens or by a specific JEM. Results. We found a crude dose response relationship with most of the indicators of DME exposure, including with the cumulative exposure index. All results were affected by adjustment for asbestos exposure. The dose response relationships between DME and lung cancer were observed among subjects never exposed to asbestos. Conclusions. Exposure to DME and to asbestos is frequently found among the same subjects, which may explain why dose-response relationships in previous studies that adjusted for asbestos exposure were inconsistent. PMID:26425123

  14. Occupational Exposure to Diesel Motor Exhaust and Lung Cancer: A Dose-Response Relationship Hidden by Asbestos Exposure Adjustment? The ICARE Study

    PubMed Central

    Matrat, Mireille; Guida, Florence; Cénée, Sylvie; Févotte, Joelle; Carton, Matthieu; Cyr, Diane; Menvielle, Gwenn; Paget-Bailly, Sophie; Radoï, Loredana; Schmaus, Annie; Bara, Simona; Velten, Michel; Luce, Danièle; Stücker, Isabelle; The Icare Study Group

    2015-01-01

    Background. In a French large population-based case-control study we investigated the dose-response relationship between lung cancer and occupational exposure to diesel motor exhaust (DME), taking into account asbestos exposure. Methods. Exposure to DME was assessed by questionnaire. Asbestos was taken into account through a global indicator of exposure to occupational carcinogens or by a specific JEM. Results. We found a crude dose response relationship with most of the indicators of DME exposure, including with the cumulative exposure index. All results were affected by adjustment for asbestos exposure. The dose response relationships between DME and lung cancer were observed among subjects never exposed to asbestos. Conclusions. Exposure to DME and to asbestos is frequently found among the same subjects, which may explain why dose-response relationships in previous studies that adjusted for asbestos exposure were inconsistent. PMID:26425123

  15. A comparison of genotoxicity of automotive exhaust particles from laboratory and environmental sources.

    PubMed

    Brooks, A L; Li, A P; Dutcher, J S; Clark, C R; Rothenberg, S J; Kiyoura, R; Bechtold, W E; McClellan, R O

    1984-01-01

    This research (1) ranked the genotoxicity of methylene chloride extracts of laboratory and environmentally collected particles and (2) evaluated the role of collection location and sample composition on genotoxic potency. Samples of exhaust from a spark-ignition automobile, light-duty diesel automobile, and a heavy-duty diesel engine operated in a laboratory on a dynamometer were studied, as well as samples taken in a highway tunnel and outside the same tunnel. The tunnel samples were collected 30 m inside or 56 m outside the exit portal at times when between 70%-95% of the traffic consisted of diesel trucks. In the Ames Salmonella mutagenicity assay, each extract produced a dose-dependent increase in mutagenicity in strain TA-98 without addition of liver S-9 fraction. Extracts from two tunnel samples collected 1 yr apart, and extracts of particles collected outside the tunnel had similar mutagenic activity. The order of mutagenic activity per microgram of extract in TA-98 without S-9 from the lowest to the highest was environmental sample less than or equal to tunnel less than heavy-duty diesel less than light-duty diesel less than spark ignition. Addition of S-9 or testing in Salmonella strains resistant to the mutagenicity of nitroaromatic compounds (TA-98 NR and TA-98 1,8-DNP6) decreased the mutagenic response. With cell killing, sister chromatid exchanges, and mutations as endpoints in Chinese hamster ovary cells (CHO), the order of potency was tunnel less than light-duty less than spark-ignition samples. All three extracts induced a similar amount of mitotic delay per microgram with or without S-9. Enhanced chromosome aberration frequency was detected only in cells exposed to extracts from spark-ignition exhaust. The data indicated that genotoxic activity was detected in each particle extract, that the potency ranking was similar using different genetic endpoints, and that the magnitude of the genotoxic potency was similar. PMID:6207015

  16. Mutagenicity of biodiesel or diesel exhaust particles and the effect of engine operating conditions

    PubMed Central

    Kisin, Elena R; Shi, X.C; Keane, Michael J; Bugarski, Aleksandar B; Shvedova, Anna A

    2015-01-01

    Background Changing the fuel supply from petroleum based ultra-low sulfur diesel (ULSD) to biodiesel and its blends is considered by many to be a viable option for controlling exposures to particulate material (PM). This is critical in the mining industry where approximately 28,000 underground miners are potentially exposed to relatively high concentrations of diesel particulate matter (DPM). This study was conducted to investigate the mutagenic potential of diesel engine emissions (DEE) from neat (B100) and blended (B50) soy-based fatty acid methyl ester (FAME) biodiesel in comparison with ULSD PM using different engine operating conditions and exhaust aftertreatment configurations. Methods The DPM samples were collected for engine equipped with either a standard muffler or a combination of the muffler and diesel oxidation catalytic converter (DOC) that was operated at four different steady-state modes. Bacterial gene mutation activity of DPM was tested on the organic solvent extracts using the Ames Salmonella assay. Results The results indicate that mutagenic activity of DPM was strongly affected by fuels, engine operating conditions, and exhaust aftertreatment systems. The mutagenicity was increased with the fraction of biodiesel in the fuel. While the mutagenic activity was observed in B50 and B100 samples collected from both light-and heavy-load operating conditions, the ULSD samples were mutagenic only at light-load conditions. The presence of DOC in the exhaust system resulted in the decreased mutagenicity when engine was fueled with B100 and B50 and operated at light-load conditions. This was not the case when engine was fueled with ULSD. Heavy-load operating condition in the presence of DOC resulted in a decrease of mutagenicity only when engine was fueled with B50, but not B100 or ULSD. Conclusions Therefore, the results indicate that DPM from neat or blended biodiesel has a higher mutagenic potency than that one of ULSD. Further research is needed to

  17. Novel object recognition ability in female mice following exposure to nanoparticle-rich diesel exhaust.

    PubMed

    Win-Shwe, Tin-Tin; Fujimaki, Hidekazu; Fujitani, Yuji; Hirano, Seishiro

    2012-08-01

    Recently, our laboratory reported that exposure to nanoparticle-rich diesel exhaust (NRDE) for 3 months impaired hippocampus-dependent spatial learning ability and up-regulated the expressions of memory function-related genes in the hippocampus of female mice. However, whether NRDE affects the hippocampus-dependent non-spatial learning ability and the mechanism of NRDE-induced neurotoxicity was unknown. Female BALB/c mice were exposed to clean air, middle-dose NRDE (M-NRDE, 47 μg/m(3)), high-dose NRDE (H-NRDE, 129 μg/m(3)), or filtered H-NRDE (F-DE) for 3 months. We then investigated the effect of NRDE exposure on non-spatial learning ability and the expression of genes related to glutamate neurotransmission using a novel object recognition test and a real-time RT-PCR analysis, respectively. We also examined microglia marker Iba1 immunoreactivity in the hippocampus using immunohistochemical analyses. Mice exposed to H-NRDE or F-DE could not discriminate between familiar and novel objects. The control and M-NRDE-exposed groups showed a significantly increased discrimination index, compared to the H-NRDE-exposed group. Although no significant changes in the expression levels of the NMDA receptor subunits were observed, the expression of glutamate transporter EAAT4 was decreased and that of glutamic acid decarboxylase GAD65 was increased in the hippocampus of H-NRDE-exposed mice, compared with the expression levels in control mice. We also found that microglia activation was prominent in the hippocampal area of the H-NRDE-exposed mice, compared with the other groups. These results indicated that exposure to NRDE for 3 months impaired the novel object recognition ability. The present study suggests that genes related to glutamate metabolism may be involved in the NRDE-induced neurotoxicity observed in the present mouse model. PMID:22659509

  18. Historical estimation of diesel exhaust exposure in a cohort study of U.S. railroad workers and lung cancer

    PubMed Central

    Laden, Francine; Hart, Jaime E.; Eschenroeder, Alan; Smith, Thomas J; Garshick, Eric

    2006-01-01

    We have previously shown an elevated risk of lung cancer mortality in diesel exhaust exposed railroad workers. To reduce exposure misclassification, we obtained extensive historical information on diesel locomotives used by each railroad. Starting in 1945, we calculated the rate each railroad converted from steam to diesel, creating annual railroad-specific weighting factors for the probability of diesel exposure. We also estimated the average annual exposure intensity based on emission factors. The US Railroad Retirement Board provided railroad assignment and work histories for 52,812 workers hired between 1939–1949, for whom we ascertained mortality 1959–1996. Among workers hired after 1945, as diesel locomotives were introduced, the relative risk of lung cancer for any exposure was 1.77 (95%CI=1.50–2.09), and there was evidence of an exposure response relationship with exposure duration. Exposed workers hired before 1945 had a relative risk of 1.30 (95%CI=1.19–1.43) for any exposure and there was no evidence of a dose response with duration. There was no evidence of increasing risk using estimated measures of intensity although the overall lung cancer risk remained elevated. In conclusion, although precise historical estimates of exposure are not available, weighting factors helped better define the exposure-response relationship of diesel exhaust with lung cancer mortality. PMID:16841258

  19. Estrogenic and anti-androgenic activities of 4-nitrophenol in diesel exhaust particles

    SciTech Connect

    Li Chunmei; Taneda, Shinji; Suzuki, Akira K. . E-mail: suzukiak@nies.go.jp; Furuta, Chie; Watanabe, Gen; Taya, Kazuyoshi

    2006-11-15

    A 4-nitrophenol (PNP) isolated from diesel exhaust particles (DEP) has been identified as a vasodilator. PNP is also a known degradation product of the insecticide parathion. We used uterotrophic and Hershberger assays to study the estrogenic and anti-androgenic activities of PNP in-vivo. In ovariectomized immature female rats injected subcutaneously with 1, 10, or 100 mg/kg PNP daily for 7 days, significant (P < 0.05) increases in uterine weight were seen in only those receiving 10 or 100 mg/kg PNP. Furthermore, in castrated immature male rats implanted with a silastic tube (length, 5 mm) containing crystalline testosterone and injected subcutaneously with 0.01, 0.1, or 1 mg/kg PNP daily for 5 days, those receiving the doses of 0.1 mg/kg showed significant (P < 0.05) weight decreases in seminal vesicles, ventral prostate, levator ani plus bulbocavernosus muscles, and glans penis. Plasma FSH and LH levels did not change in female rats but were significantly (P < 0.05) increased in male rats treated with 0.1 mg/kg PNP. These results clearly demonstrated that PNP has estrogenic and anti-androgenic activities in-vivo. Our results therefore suggest that diesel exhaust emissions and the degradation of parathion can lead to accumulation of PNP in air, water, and soil and thus could have serious deleterious effects on wildlife and human health.

  20. Analysis of mid-tropospheric space shuttle exhausted aluminum oxide particles

    NASA Astrophysics Data System (ADS)

    Cofer, Wesley R.; Lala, G. Garland; Wightman, James P.

    Aluminum oxide (Al 2O 3) particles from the exhaust of the space shuttle were collected from the shuttle column cloud immediately after the launch of STS-61A on 30 October 1985. The participates were collected on Teflon filters during a tight descending aircraft spiral maneuver over the altitude interval of 7.6-4.6 km. Scanning electron microscope (SEM) examination of the particles revealed that they were virtually all spherical and ranged in diameter from about 0.1 μm to 10 μm. Particles of < 0.1 μm in diameter were not readily visible in the SEM photomicrographs; however, such particles would not be captured efficiently on the Teflon filters used. Results from energy dispersive analysis by X-ray (EDAX) and electron spectroscopy for chemical analysis (ESCA) confirmed that the particles were predominantly composed of Al and O 2. A particle size distribution was determined from the Al 2O 3 samples. The distribution was bimodal, with one observed peak centered near 2.0 μm. The data indicated the existence of another mode centered at a diameter of < 0.3 μm, but could not be accurately located because our technique cut off at diameters of < 0.1 μm. A mass median diameter of slightly < 2 μm was determined. The collection was evaluated for ice nucleation activity, using the filter technique with a static vapor-diffusion chamber. Only a small fraction (about 1:10 6) of active ice nuclei were determined among the Al 2O 3 particulates.

  1. Diesel exhaust particulate (DEP) and nanoparticle exposures: what do DEP human clinical studies tell us about potential human health hazards of nanoparticles?

    PubMed

    Hesterberg, Thomas W; Long, Christopher M; Lapin, Charles A; Hamade, Ali K; Valberg, Peter A

    2010-07-01

    Engineered nanoparticles (ENPs) are increasingly tested in cellular and laboratory-animal experiments for hazard potential, but there is a lack of health effects data for humans exposed to ENPs. However, human data for another source of nanoparticle (NP) exposure are available, notably for the NPs contained in diesel exhaust particulate (DEP). Studies of human volunteers exposed to diesel exhaust (DE) in research settings report DEP-NP number concentrations (i.e., >10(6) particles/cm(3)) that exceed number concentrations reported for worst-case exposure conditions for workers manufacturing and handling ENPs. Recent human DE exposure studies, using sensitive physiological instrumentation and well-characterized exposure concentrations and durations, suggest that elevated DE exposures from pre-2007 engines may trigger short-term changes in, for example, lung and systemic inflammation, thrombogenesis, vascular function, and brain activity. Considerable uncertainty remains both as to which DE constituents underlie the observed responses (i.e., DEP NPs, DEP mass, DE gases), and as to the implications of the observed short-term changes for the development of disease. Even so, these DE human clinical data do not give evidence of a unique toxicity for NPs as compared to other small particles. Of course, physicochemical properties of toxicological relevance may differ between DEP NPs and other NPs, yet overall, the DE human clinical data do not support the idea that elevated levels of NPs per se (at least in the DEP context) must be acutely toxic by virtue of their nano-sized nature alone. PMID:20462394

  2. Novel object recognition ability in female mice following exposure to nanoparticle-rich diesel exhaust

    SciTech Connect

    Win-Shwe, Tin-Tin; Fujimaki, Hidekazu; Fujitani, Yuji; Hirano, Seishiro

    2012-08-01

    Recently, our laboratory reported that exposure to nanoparticle-rich diesel exhaust (NRDE) for 3 months impaired hippocampus-dependent spatial learning ability and up-regulated the expressions of memory function-related genes in the hippocampus of female mice. However, whether NRDE affects the hippocampus-dependent non-spatial learning ability and the mechanism of NRDE-induced neurotoxicity was unknown. Female BALB/c mice were exposed to clean air, middle-dose NRDE (M-NRDE, 47 μg/m{sup 3}), high-dose NRDE (H-NRDE, 129 μg/m{sup 3}), or filtered H-NRDE (F-DE) for 3 months. We then investigated the effect of NRDE exposure on non-spatial learning ability and the expression of genes related to glutamate neurotransmission using a novel object recognition test and a real-time RT-PCR analysis, respectively. We also examined microglia marker Iba1 immunoreactivity in the hippocampus using immunohistochemical analyses. Mice exposed to H-NRDE or F-DE could not discriminate between familiar and novel objects. The control and M-NRDE-exposed groups showed a significantly increased discrimination index, compared to the H-NRDE-exposed group. Although no significant changes in the expression levels of the NMDA receptor subunits were observed, the expression of glutamate transporter EAAT4 was decreased and that of glutamic acid decarboxylase GAD65 was increased in the hippocampus of H-NRDE-exposed mice, compared with the expression levels in control mice. We also found that microglia activation was prominent in the hippocampal area of the H-NRDE-exposed mice, compared with the other groups. These results indicated that exposure to NRDE for 3 months impaired the novel object recognition ability. The present study suggests that genes related to glutamate metabolism may be involved in the NRDE-induced neurotoxicity observed in the present mouse model. -- Highlights: ► The effects of nanoparticle-induced neurotoxicity remain unclear. ► We investigated the effect of exposure to

  3. Particle exhaust schemes in the DIII-D advanced divertor configuration

    SciTech Connect

    Menon, M.M.; Mioduszewski, P.K.

    1989-01-01

    For density control in long-pulse operation, the open divertor on the DIII-D tokamak will be equipped with a baffled chamber and a pumping system. The throat of the baffle chamber is sized to provide optimal pumping for the typical plasma equilibrium configuration. Severe limitations on the toroidal conductance of this baffle chamber require the use of in-vessel pumping to achieve the desired particle exhaust of about 25 Torr{center dot}l/s. Two separate pumping schemes are considered: an array of titanium getter modules based on the design developed by the Tore Supra team and a cryocondensation pump. The merits and demerits of each scheme are analyzed, and the design considerations introduced by the tokamak environment are brought out. 3 refs., 5 figs.

  4. Short-term exposure of rodents to diesel exhausts: usefulness for studies of genotoxic and immunotoxic effects.

    PubMed

    Nilsen, A; Trønnes, T; Westerholm, R; Rannug, U; Nilsen, O G; Helleberg, H; Kautiainen, A; Hedenskog, M; Törnqvist, M

    1999-03-01

    An exposure facility was tested with regard to the information obtainable from short-term animal experiments for the assessment of health hazards from automotive engine exhausts. Indicators of immunotoxicity and genotoxicity were studied in guinea pigs and mice, respectively, exposed for 2 weeks, 8 h/day, to ten times diluted exhausts from a one-cylinder research diesel engine running at constant load. Regulated and non-regulated pollutants were determined. Besides increased number of lavageable cells in the airways, exposed guinea pigs exhibited, after immunization and challenge to ovalbumin, reduced leukotrienes B4 and C4 in lavage fluid and reduced anti-ovalbumin IgG in serum. Absence of increased CYP1A activity indicated that the exposure was below the threshold for induction of these enzymes. Instead a certain reduction of this activity indicated interaction with active enzyme sites. In vivo doses of some reactive metabolites of low molecular mass were measured by adducts to hemoglobin. Doses from aliphatic epoxides were low, in accordance with low hydrocarbon levels in the exhaust. The levels of hemoglobin adducts from aldehydes showed no clearcut influences of exposure. Genetic effects determined by DNA fingerprint analysis were indicated. It is concluded that repeated dose inhalation exposure of small numbers of animals is a useful mode of exposure for studying parameters that may elucidate toxic effects of air pollutants emitted from automotive engines, with a possibility to evaluate engine and fuel with regard to health hazards. PMID:10227576

  5. Alteration of pulmonary immunity to Listeria monocytogenes by diesel exhaust particles (DEPs). I. Effects of DEPs on early pulmonary responses.

    PubMed Central

    Yin, Xue-Jun; Schafer, Rosana; Ma, Jane Y C; Antonini, James M; Weissman, David D; Siegel, Paul D; Barger, Mark W; Roberts, Jenny R; Ma, Joseph K-H

    2002-01-01

    It has been hypothesized that diesel exhaust particles (DEPs) aggravate pulmonary bacterial infection by both innate and cell-mediated immune mechanisms. To test this hypothesis, we investigated the effects of DEP exposure on the functions of alveolar macrophages (AMs) and lymphocytes from lung-draining lymph nodes using a rat Listeria monocytogenes infection model. In the present study, we focused on the effects of DEP exposure on AM functions, including phagocytic activity and secretion of proinflammatory cytokines. The Listeria infection model was characterized by an increase in neutrophil count, albumin content, and acellular lactate dehydrogenase activity in the bronchoalveolar lavage (BAL) fluid at 3 and 7 days postinfection. Short-term DEP inhalation (50 and 100 mg/m(3), 4 hr) resulted in a dose-dependent suppression of lung clearance of Listeria, with the highest bacteria count occurring at day 3. This aggravated bacterial infection was consistent with the inhibitory effect of DEPs on macrophage functions. DEPs suppressed phagocytosis and Listeria-induced basal secretion of interleukin-1ss (IL-1ss) and IL-12 by AMs in a dose-dependent manner. The amount of IL-1ss and IL-12 in the BAL fluid was also reduced by DEP exposure. In addition, DEPs decreased Listeria-induced lipopolysaccharide-stimulated secretion of tumor necrosis factor-alpha (TNF-alpha), IL-1ss, and IL-12 from AMs. These results suggest that DEPs retard bacterial clearance by inhibiting AM phagocytosis and weaken the innate immunity by inhibiting AM secretion of IL-1ss and TNF-alpha. DEPs may also suppress cell-mediated immunity by inhibiting AM secretion of IL-12, a key cytokine for the initiation of T helper type 1 cell development in Listeria infection. PMID:12417481

  6. Inflammation-Related Effects of Diesel Engine Exhaust Particles: Studies on Lung Cells In Vitro

    PubMed Central

    Schwarze, P. E.; Totlandsdal, A. I.; Låg, M.; Refsnes, M.; Holme, J. A.; Øvrevik, J.

    2013-01-01

    Diesel exhaust and its particles (DEP) have been under scrutiny for health effects in humans. In the development of these effects inflammation is regarded as a key process. Overall, in vitro studies report similar DEP-induced changes in markers of inflammation, including cytokines and chemokines, as studies in vivo. In vitro studies suggest that soluble extracts of DEP have the greatest impact on the expression and release of proinflammatory markers. Main DEP mediators of effects have still not been identified and are difficult to find, as fuel and engine technology developments lead to continuously altered characteristics of emissions. Involved mechanisms remain somewhat unclear. DEP extracts appear to comprise components that are able to activate various membrane and cytosolic receptors. Through interactions with receptors, ion channels, and phosphorylation enzymes, molecules in the particle extract will trigger various cell signaling pathways that may lead to the release of inflammatory markers directly or indirectly by causing cell death. In vitro studies represent a fast and convenient system which may have implications for technology development. Furthermore, knowledge regarding how particles elicit their effects may contribute to understanding of DEP-induced health effects in vivo, with possible implications for identifying susceptible groups of people and effect biomarkers. PMID:23509760

  7. Photothermal laser deflection, an innovative technique to measure particles in exhausts

    NASA Astrophysics Data System (ADS)

    Hess, Cecil F.

    1993-10-01

    Photothermal Laser Deflection (PLD) is an analytical technique to measure in real-time the mass concentration of particles and gaseous exhaust pollutants in a variety of combustion devices (e.g., gas turbine engines and rockets). PLD uses a pump laser to locally heat the particle or gaseous species, thus changing the refractive index of the surrounding gas to form a thermal lens. A probe laser beam travelling through the thermal lens is temporarily deflected, and the amount of deflection is proportional to the species mass concentration. The experiments and analyses conducted during phase 1 demonstrated the feasibility of PLD in measuring the mass concentration of both soot particles and NO2 at a repetition rate of 25 HZ. PLD response was linear at soot concentrations from 0.3 to 10 mg/cubic meters at NO2 concentrations from approximately 6 to 208 ppm. Strategies to measure lower concentrations have been defined and include focusing the probe beam onto the face of the bi-cell detector. The large dynamic range, fast acquisition rate, and ability to measure particulate and gaseous pollutants makes PLD superior to other available methods.

  8. Diesel exhaust exposure and smoking: A case-referent study of lung cancer among Swedish dock workers

    SciTech Connect

    Emmelin, A.; Nystroem, L.W.; Wall, S. )

    1993-05-01

    We studied 50 lung cancer cases and 154 matched referents, all dock workers, for whom we obtained smoking information and employment histories. We assessed exposures from information on annual diesel fuel consumption from each of the 15 ports included. We used a smoker/nonsmoker term and three exposure variables (machine time, cumulative fuel, and exposed time with fuel consumption above a minimum cutpoint) in the analyses, with three categories for each exposure variable. Odds ratios (ORs) for medium and high exposure groups are consistently higher than reference (low), with an increasing exposure-response trend that is most marked for the exposed time variable (ORs: low = 1.0; medium = 1.6; high = 2.8). When smoking and that exposure variable are simultaneously included in the analyses, odds ratios for the medium (OR = 2.7) and high (OR = 6.8) levels of exposure increase, as does the odds ratio for smoking. Separating smokers and nonsmokers, with the low exposed nonsmokers as the common reference category, the odds ratios are 1.6 (medium) and 2.9 (high) for the nonsmokers, and 10.7 (medium) and 28.9 (high) for smokers. These results indicate an independent effect of diesel exhaust exposure and a strong interaction between smoking and diesel exhaust.

  9. Variability in Bioreactivity Linked to Changes in Size and Zeta Potential of Diesel Exhaust Particles in Human Immune Cells

    PubMed Central

    Sarkar, Srijata; Zhang, Lin; Subramaniam, Prasad; Lee, Ki-Bum; Garfunkel, Eric; Strickland, Pamela A. Ohman.; Mainelis, Gediminas; Lioy, Paul J.; Tetley, Teresa D.; Chung, Kian Fan; Zhang, Junfeng; Ryan, Mary; Porter, Alex; Schwander, Stephan

    2014-01-01

    Acting as fuel combustion catalysts to increase fuel economy, cerium dioxide (ceria, CeO2) nanoparticles have been used in Europe as diesel fuel additives (Envirox™). We attempted to examine the effects of particles emitted from a diesel engine burning either diesel (diesel exhaust particles, DEP) or diesel doped with various concentrations of CeO2 (DEP-Env) on innate immune responses in THP-1 and primary human peripheral blood mononuclear cells (PBMC). Batches of DEP and DEP-Env were obtained on three separate occasions using identical collection and extraction protocols with the aim of determining the reproducibility of particles generated at different times. However, we observed significant differences in size and surface charge (zeta potential) of the DEP and DEP-Env across the three batches. We also observed that exposure of THP-1 cells and PBMC to identical concentrations of DEP and DEP-Env from the three batches resulted in statistically significant differences in bioreactivity as determined by IL-1β, TNF-α, IL-6, IFN-γ, and IL-12p40 mRNA (by qRT-PCR) and protein expression (by ELISPOT assays). Importantly, bioreactivity was noted in very tight ranges of DEP size (60 to 120 nm) and zeta potential (−37 to −41 mV). Thus, these physical properties of DEP and DEP-Env were found to be the primary determinants of the bioreactivity measured in this study. Our findings also point to the potential risk of over- or under- estimation of expected bioreactivity effects (and by inference of public health risks) from bulk DEP use without taking into account potential batch-to-batch variations in physical (and possibly chemical) properties. PMID:24825358

  10. Histological examination of the rat after long-term exposure to subtoxic automotive exhaust gas.

    PubMed

    Roggendorf, W; Neumann, H; Thron, H L; Schneider, H; Sarasa-Corral, J L

    1981-07-01

    Regarding the potential impact of traffic-born air pollutants on public health, in recent years attention has increasingly been focused on the possible effects on the cardiovascular system. In order to investigate this problem further, the influence of long-term exhaust gas exposure on rats has been studied. One hundred Wistar rats of either sex were exposed 5 X 8 h/week up to 28 months to an atmosphere polluted by the emissions of an idling Otto engine, CO concentrations held constant at 90 ppm. A second group (50 rats) was exposed to 250 ppm for 6 months. Blood parameters and body weight were controlled. Specimens of CNS, heart, vessels, kidney etc. were investigated light microscopically. Focal necroses of the myocardium with inflammatory reactions as well as interstitial fibrosis were found in the heart muscle of the 90 ppm group. In the 250 ppm group endothelial proliferations, edema of the intima and deposits of proteoglycanes in the media were observed. We conclude that subtoxic concentrations of CO which only lead to slight morphologic changes may aggravate preexisting lesions caused by high risk conditions, e.g., hypertension or hypercholesteremia. PMID:7271450

  11. Particle exposure in a baroque church during Sunday Masses.

    PubMed

    Polednik, Bernard

    2013-10-01

    Particle concentrations were measured in a Baroque church during five Sunday Masses. The highest particle number and mass concentrations were observed when both candles and the incense were burned. They were respectively 16.8 and 14.3 times higher than outdoors for submicron particles. The exposure to particles experienced by the churchgoers, especially priests and church workers who participated in several Masses on that day, was considerably higher than the exposure experienced at the same time outdoors. PMID:23972742

  12. Whole and Particle-Free Diesel Exhausts Differentially Affect Cardiac Electrophysiology, Blood Pressure, and Autonomic Balance in Heart Failure–Prone Rats

    PubMed Central

    Farraj, Aimen K.

    2012-01-01

    Epidemiological studies strongly link short-term exposures to vehicular traffic and particulate matter (PM) air pollution with adverse cardiovascular (CV) events, especially in those with preexisting CV disease. Diesel engine exhaust is a key contributor to urban ambient PM and gaseous pollutants. To determine the role of gaseous and particulate components in diesel exhaust (DE) cardiotoxicity, we examined the effects of a 4-h inhalation of whole DE (wDE) (target PM concentration: 500 µg/m3) or particle-free filtered DE (fDE) on CV physiology and a range of markers of cardiopulmonary injury in hypertensive heart failure–prone rats. Arterial blood pressure (BP), electrocardiography, and heart rate variability (HRV), an index of autonomic balance, were monitored. Both fDE and wDE decreased BP and prolonged PR interval during exposure, with more effects from fDE, which additionally increased HRV triangular index and decreased T-wave amplitude. fDE increased QTc interval immediately after exposure, increased atrioventricular (AV) block Mobitz II arrhythmias shortly thereafter, and increased serum high-density lipoprotein 1 day later. wDE increased BP and decreased HRV root mean square of successive differences immediately postexposure. fDE and wDE decreased heart rate during the 4th hour of postexposure. Thus, DE gases slowed AV conduction and ventricular repolarization, decreased BP, increased HRV, and subsequently provoked arrhythmias, collectively suggesting parasympathetic activation; conversely, brief BP and HRV changes after exposure to particle-containing DE indicated a transient sympathetic excitation. Our findings suggest that whole- and particle-free DE differentially alter CV and autonomic physiology and may potentially increase risk through divergent pathways. PMID:22543275

  13. Improved design of a tangential entry cyclone separator for separation of particles from exhaust gas of diesel engine.

    PubMed

    Mukhopadhyay, N

    2011-01-01

    An effective design of cyclone separator with tangential inlet is developed applying an equation derived from the correlation of collection efficiency with maximum pressure drop components of the cyclone, which can efficiently remove the particles around 1microm of the exhaust gas of diesel engine. PMID:22324145

  14. Bioassay-Directed Fractionation and Sub-fractionation for Mutagenicity and Chemical Analysis of Diesel Exhaust Particles

    EPA Science Inventory

    Several types of diesel exhaust particles (DEPs) have been used for toxicology studies, including a high-organic automobile DEP (A-DEP) from Japan, and a low-organic forklift DEP developed by the National Institute of Standards and Technology (N-DEP). However, these DEPs were no...

  15. NANOMETER SIZE DIESEL EXHAUST PARTICLES ARE SELECTIVELY TOXIC TO DOPAMINERGIC NEURONS: THE ROLE OF MICROGLIA, PHAGOCYTOSIS, AND NADPH OXIDASE.

    EPA Science Inventory

    This manuscript describes the neurotoxic response of cultured brain cells to diesel exhaust particles (DEP). DEP produces an early production of free radicals (i.e., oxidative stress) in one CNS cell type (the microglial) and the subsequent degeneration of specific neuronal...

  16. Comparison of genotoxicity of automotive exhaust particles from laboratory and environmental sources

    SciTech Connect

    Brooks, A.L.; Li, A.P.; Dutcher, J.S.; Clark, C.R.; Rothenberg, S.J.; Kiyoura, R.; Bechtold, W.E.; McClellan, R.O.

    1984-01-01

    This research (1) ranked the genotoxicity of methylene chloride extracts of laboratory and environmentally collected particles and (2) evaluated the role of collection location and sample composition on genotoxic potency. Samples of exhaust from a spark-ignition automobile, light-duty diesel automobile, and a heavy-duty diesel engine operated in a laboratory on a dynamometer were studied, as well as samples taken in a highway tunnel and outside the same tunnel. In the Ames Salmonella mutagenicity assay, each extract produced a dose-dependent increase in mutagenicity in strain TA-98 without addition of liver S-9 fraction. The order of mutagenic activity per ..mu..g of extract in TA-98 without S-9 from the lowest to the highest was environmental sample less than or equal to tunnel < heavy-duty diesel < light-duty diesel < spark ignition. With cell killing, sister chromatid exchanges, and mutations as endpoints in Chinese hamster ovary cells (CHO), the order of potency was tunnel < light-duty < spark-ignition samples. The data indicated that genotoxic activity was detected in each particle extract, that the potency ranking was similar using different genetic endpoints, and that the magnitude of the genotoxic potency was similar.

  17. Metal particle emissions in the exhaust stream of diesel engines: an electron microscope study.

    PubMed

    Liati, Anthi; Schreiber, Daniel; Dimopoulos Eggenschwiler, Panayotis; Arroyo Rojas Dasilva, Yadira

    2013-12-17

    Scanning electron microscopy and transmission electron microscopy were applied to investigate the morphology, mode of occurrence and chemical composition of metal particles (diesel ash) in the exhaust stream of a small truck outfitted with a typical after-treatment system (a diesel oxidation catalyst (DOC) and a downstream diesel particulate filter (DPF)). Ash consists of Ca-Zn-P-Mg-S-Na-Al-K-phases (lube-oil related), Fe, Cr, Ni, Sn, Pb, Sn (engine wear), and Pd (DOC coating). Soot agglomerates of variable sizes (<0.5-5 μm) are abundant upstream of the DPF and are ash-free or contain notably little attached ash. Post-DPF soot agglomerates are very few, typically large (>1-5 μm, exceptionally 13 μm), rarely <0.5 μm, and contain abundant ash carried mostly from inside the DPF. The ash that reaches the atmosphere also occurs as separate aggregates ca. 0.2-2 μm in size consisting of sintered primary phases, ca. 20-400 nm large. Insoluble particles of these sizes may harm the respiratory and cardiovascular systems. The DPF probably promotes breakout of large soot agglomerates (mostly ash-bearing) by favoring sintering. Noble metals detached from the DOC coating may reach the ambient air. Finally, very few agglomerates of Fe-oxide nanoparticles form newly from engine wear and escape into the atmosphere. PMID:24274188

  18. A toxicology suite adapted for comparing parallel toxicity responses of model human lung cells to diesel exhaust particles and their extracts

    PubMed Central

    Turner, Jane; Hernandez, Mark; Snawder, John E.; Handorean, Alina; McCabe, Kevin M.

    2015-01-01

    Epidemiological studies have shown that exposure to airborne particulate matter can be an important risk factor for some common respiratory diseases. While many studies have shown that particulate matter exposures are associated with inflammatory reactions, the role of specific cellular responses in the manifestation of primary hypersensitivities, and the progression of respiratory diseases remains unclear. In order to better understand mechanisms by which particulate matter can exert adverse health effects, more robust approaches to support in vitro studies are warranted. In response to this need, a group of accepted toxicology assays were adapted to create an analytical suite for screening and evaluating the effects of important, ubiquitous atmospheric pollutants on two model human lung cell lines (epithelial and immature macrophage). To demonstrate the utility of this suite, responses to intact diesel exhaust particles, and mass-based equivalent doses of their organic extracts were examined. Results suggest that extracts have the potential to induce greater biological responses than those associated with their colloidal counterpart. Additionally, macrophage cells appear to be more susceptible to the cytotoxic effects of both intact diesel exhaust particles and their organic extract, than epithelial cells tested in parallel. As designed, the suite provided a more robust basis for characterizing toxicity mechanisms than the analysis of any individual assay. Findings suggest that cellular responses to particulate matter are cell line dependent, and show that the collection and preparation of PM and/or their extracts have the potential to impact cellular responses relevant to screening fundamental elements of respiratory toxicity. PMID:26412929

  19. The effect of thymoquinone treatment on the combined renal and pulmonary toxicity of cisplatin and diesel exhaust particles.

    PubMed

    Ali, Badreldin H; Al Za'abi, Mohammed; Shalaby, Asem; Manoj, Priyadarsini; Waly, Mostafa I; Yasin, Javed; Fahim, Mohamed; Nemmar, Abderrahim

    2015-12-01

    Particulate air pollution (PAP) exposure is associated with increased morbidity and mortality, particularly in patients with renal disease. However, there are only a few studies on the interaction between PAP and renal injury, and none on agents that may ameliorate it. We studied the interaction between cisplatin (CP) nephrotoxicity and a single exposure to diesel exhaust particle (DEP) in rats 24 h before sacrifice, and assessed the effect of co-treatment with the active ingredient in Nigella Sativa seed oil, thymoquinone (TQ) thereon. Rats were injected intraperitoneally with CP (6 mg/kg) and four days later, they were exposed intratracheally to DEP (0.5 mg/kg), and were sacrificed 24 h later. Oral TQ (20 mg/kg) was given daily throughout the experimental period. CP alone caused several physiological, biochemical, and histopathological changes that included reduced growth and creatinine clearance, and raised plasma neutrophil gelatinase-associated lipocalin (NGAL), interleukin 6 (IL-6) and C-reactive protein (CRP), creatinine and urea concentrations, and urinary N-acetyl-b-D-glucosaminidase (NAG) activities. It adversely affected several indices of oxidative damage in the kidneys, and induced renal tubular necrosis. Most of these actions were significantly potentiated in rats given both CP and DEP. TQ significantly abrogated many of the effects of CP and DEP, given alone and in combination. These results provide experimental evidence that subjects with renal diseases can be at higher risk from PAP, and that TQ, pending further pharmacological and toxicological studies, can be considered a useful agent in patients with renal diseases and exposed to PAP. PMID:25925792

  20. Lack of acute phase response in the livers of mice exposed to diesel exhaust particles or carbon black by inhalation

    PubMed Central

    Saber, Anne T; Halappanavar, Sabina; Folkmann, Janne K; Bornholdt, Jette; Boisen, Anne Mette Z; Møller, Peter; Williams, Andrew; Yauk, Carole; Vogel, Ulla; Loft, Steffen; Wallin, Håkan

    2009-01-01

    Background Epidemiologic and animal studies have shown that particulate air pollution is associated with increased risk of lung and cardiovascular diseases. Although the exact mechanisms by which particles induce cardiovascular diseases are not known, studies suggest involvement of systemic acute phase responses, including C-reactive protein (CRP) and serum amyloid A (SAA) in humans. In this study we test the hypothesis that diesel exhaust particles (DEP) – or carbon black (CB)-induced lung inflammation initiates an acute phase response in the liver. Results Mice were exposed to filtered air, 20 mg/m3 DEP or CB by inhalation for 90 minutes/day for four consecutive days; we have previously shown that these mice exhibit pulmonary inflammation (Saber AT, Bornholdt J, Dybdahl M, Sharma AK, Loft S, Vogel U, Wallin H. Tumor necrosis factor is not required for particle-induced genotoxicity and pulmonary inflammation., Arch. Toxicol. 79 (2005) 177–182). As a positive control for the induction of an acute phase response, mice were exposed to 12.5 mg/kg of lipopolysaccharide (LPS) intraperitoneally. Quantitative real time RT-PCR was used to examine the hepatic mRNA expression of acute phase proteins, serum amyloid P (Sap) (the murine homologue of Crp) and Saa1 and Saa3. While significant increases in the hepatic expression of Sap, Saa1 and Saa3 were observed in response to LPS, their levels did not change in response to DEP or CB. In a comprehensive search for markers of an acute phase response, we analyzed liver tissue from these mice using high density DNA microarrays. Globally, 28 genes were found to be significantly differentially expressed in response to DEP or CB. The mRNA expression of three of the genes (serine (or cysteine) proteinase inhibitor, clade A, member 3C, apolipoprotein E and transmembrane emp24 domain containing 3) responded to both exposures. However, these changes were very subtle and were not confirmed by real time RT-PCR. Conclusion Our findings

  1. A review of commuter exposure to ultrafine particles and its health effects

    NASA Astrophysics Data System (ADS)

    Knibbs, Luke D.; Cole-Hunter, Tom; Morawska, Lidia

    2011-05-01

    Ultrafine particles (UFPs, <100 nm) are produced in large quantities by vehicular combustion and are implicated in causing several adverse human health effects. Recent work has suggested that a large proportion of daily UFP exposure may occur during commuting. However, the determinants, variability and transport mode-dependence of such exposure are not well-understood. The aim of this review was to address these knowledge gaps by distilling the results of 'in-transit' UFP exposure studies performed to-date, including studies of health effects. We identified 47 exposure studies performed across 6 transport modes: automobile, bicycle, bus, ferry, rail and walking. These encompassed approximately 3000 individual trips where UFP concentrations were measured. After weighting mean UFP concentrations by the number of trips in which they were collected, we found overall mean UFP concentrations of 3.4, 4.2, 4.5, 4.7, 4.9 and 5.7 × 10 4 particles cm -3 for the bicycle, bus, automobile, rail, walking and ferry modes, respectively. The mean concentration inside automobiles travelling through tunnels was 3.0 × 10 5 particles cm -3. While the mean concentrations were indicative of general trends, we found that the determinants of exposure (meteorology, traffic parameters, route, fuel type, exhaust treatment technologies, cabin ventilation, filtration, deposition, UFP penetration) exhibited marked variability and mode-dependence, such that it is not necessarily appropriate to rank modes in order of exposure without detailed consideration of these factors. Ten in-transit health effects studies have been conducted and their results indicate that UFP exposure during commuting can elicit acute effects in both healthy and health-compromised individuals. We suggest that future work should focus on further defining the contribution of in-transit UFP exposure to total UFP exposure, exploring its specific health effects and investigating exposures in the developing world.

  2. Commuter exposure to inhalable, thoracic and alveolic particles in various transportation modes in Delhi.

    PubMed

    Kumar, Pramod; Gupta, N C

    2016-01-15

    A public health concern is to understand the linkages between specific pollution sources and adverse health impacts. Commuting can be viewed as one of the significant-exposure activity in high-vehicle density areas. This paper investigates the commuter exposure to inhalable, thoracic and alveolic particles in various transportation modes in Delhi, India. Air pollution levels are significantly contributed by automobile exhaust and also in-vehicle exposure can be higher sometime than ambient levels. Motorcycle, auto rickshaw, car and bus were selected to study particles concentration along two routes in Delhi between Kashmere Gate and Dwarka. The bus and auto rickshaw were running on compressed natural gas (CNG) while the car and motorcycle were operated on gasoline fuel. Aerosol spectrometer was employed to measure inhalable, thoracic and alveolic particles during morning and evening rush hours for five weekdays. From the study, we observed that the concentration levels of these particles were greatly influenced by transportation modes. Concentrations of inhalable particles were found higher during morning in auto rickshaw (332.81 ± 90.97 μg/m(3)) while the commuter of bus exhibited higher exposure of thoracic particles (292.23 ± 110.45 μg/m(3)) and car commuters were exposed to maximum concentrations of alveolic particles (222.37 ± 26.56 μg/m(3)). We observed that in evening car commuters experienced maximum concentrations of all sizes of particles among the four commuting modes. Interestingly, motorcycle commuters were exposed to lower levels of inhalable and thoracic particles during morning and evening hours as compared to other modes of transport. The mean values were found greater than the median values for all the modes of transport suggesting that positive skewed distributions are characteristics of naturally occurring phenomenon. PMID:26439646

  3. Concentrations of ultrafine particles at a highway toll collection booth and exposure implications for toll collectors.

    PubMed

    Cheng, Yu-Hsiang; Huang, Cheng-Hsiung; Huang, Hsiao-Lin; Tsai, Chuen-Jinn

    2010-12-15

    Research regarding the magnitude of ultrafine particle levels at highway toll stations is limited. This study measured ambient concentrations of ultrafine particles at a highway toll station from October 30 to November 1 and November 5 to November 6, 2008. A scanning mobility particle sizer was used to measure ultrafine particle concentrations at a ticket/cash tollbooth. Levels of hourly average ultrafine particles at the tollbooth were about 3-6 times higher than those in urban backgrounds, indicating that a considerable amount of ultrafine particles are exhausted from passing vehicles. A bi-modal size distribution pattern with a dominant mode at about <6 nm and a minor mode at about 40 nm was observed at the tollbooth. The high amounts of nanoparticles in this study can be attributed to gas-to-particle reactions in fresh fumes emitted directly from vehicles. The influences of traffic volume, wind speed, and relative humidity on ultrafine particle concentrations were also determined. High ambient concentrations of ultrafine particles existed under low wind speed, low relative humidity, and high traffic volume. Although different factors account for high ambient concentrations of ultrafine particles at the tollbooth, measurements indicate that toll collectors who work close to traffic emission sources have a high exposure risk. PMID:21071066

  4. Detection of very large ions in aircraft gas turbine engine combustor exhaust: charged small soot particles?

    NASA Astrophysics Data System (ADS)

    Wilhelm, S.; Haverkamp, H.; Sorokin, A.; Arnold, F.

    Small electrically charged soot particles (CSP) present in the exhaust of a jet aircraft engine combustor have been detected by a Large Ion Mass Spectrometer and quantitatively measured by an Ion Mobility Analyzer. The size and concentration measurements which took place at an aircraft gas-turbine engine combustor test-rig at the ground covered different combustor conditions (fuel flow=FF, fuel sulphur content=FSC). At the high-pressure turbine stage of the engine, CSP-diameters were mostly around 6 nm and CSP-concentrations reached up to 4.8×10 7 cm -3 (positive and negative) corresponding to a CSP-emission index ECSP=2.5×10 15 CSP kg -1 fuel burnt. The ECSP increased with FF but did not increase with FSC. The latter indicates that sulphur was not a major component of the large ions. Possible CSP-sources and CSP-sinks as well as CSP-roles are discussed.

  5. Bioassay-directed fractionation and salmonella mutagenicity of automobile and forklift diesel exhaust particles.

    PubMed Central

    DeMarini, David M; Brooks, Lance R; Warren, Sarah H; Kobayashi, Takahiro; Gilmour, M Ian; Singh, Pramila

    2004-01-01

    Many pulmonary toxicity studies of diesel exhaust particles (DEPs) have used an automobile-generated sample (A-DEPs) whose mutagenicity has not been reported. In contrast, many mutagenicity studies of DEPs have used a forklift-generated sample (SRM 2975) that has been evaluated in only a few pulmonary toxicity studies. Therefore, we evaluated the mutagenicity of both DEPs in Salmonella coupled to a bioassay-directed fractionation. The percentage of extractable organic material (EOM) was 26.3% for A-DEPs and 2% for SRM 2975. Most of the A-EOM (~55%) eluted in the hexane fraction, reflecting the presence of alkanes and alkenes, typical of uncombusted fuel. In contrast, most of the SRM 2975 EOM (~58%) eluted in the polar methanol fraction, indicative of oxygenated and/or nitrated organics derived from combustion. Most of the direct-acting, base-substitution activity of the A-EOM eluted in the hexane/dichloromethane (DCM) fraction, but this activity eluted in the polar methanol fraction for the SRM 2975 EOM. The direct-acting frameshift mutagenicity eluted across fractions of A-EOM, whereas > 80% eluted only in the DCM fraction of SRM 2975 EOM. The A-DEPs were more mutagenic than SRM 2975 per mass of particle, having 227 times more polycyclic aromatic hydrocarbon-type and 8-45 more nitroarene-type mutagenic activity. These differences were associated with the different conditions under which the two DEP samples were generated and collected. A comprehensive understanding of the mechanisms responsible for the health effects of DEPs requires the evaluation of DEP standards for a variety of end points, and our results highlight the need for multidisciplinary studies on a variety of representative samples of DEPs. PMID:15175166

  6. Elements and polycyclic aromatic hydrocarbons in exhaust particles emitted by light-duty vehicles.

    PubMed

    Alves, Célia A; Barbosa, Cátia; Rocha, Sónia; Calvo, Ana; Nunes, Teresa; Cerqueira, Mário; Pio, Casimiro; Karanasiou, Angeliki; Querol, Xavier

    2015-08-01

    The main purpose of this work was to evaluate the chemical composition of particulate matter (PM) emitted by eight different light-duty vehicles. Exhaust samples from petrol and diesel cars (Euro 3 to Euro 5) were collected in a chassis dynamometer facility. To simulate the real-world driving conditions, three ARTEMIS cycles were followed: road, to simulate a fluid traffic flow and urban with hot and cold starts, to simulate driving conditions in cities. Samples were analysed for the water-soluble ions, for the elemental composition and for polycyclic aromatic hydrocarbons (PAHs), respectively, by ion chromatography, inductively coupled plasma atomic emission spectroscopy (ICP-AES), inductively coupled plasma mass spectrometry (ICP-MS) and gas chromatography-mass spectrometry (GC-MS). Nitrate and phosphate were the major water-soluble ions in the exhaust particles emitted from diesel and petrol vehicles, respectively. The amount of material emitted is affected by the vehicle age. For vehicles ≥Euro 4, most elements were below the detection limits. Sodium, with emission factors in the ranges 23.5-62.4 and 78.2-227μg km(-1), for petrol and diesel Euro 3 vehicles, respectively, was the major element. The emission factors of metallic elements indicated that diesel vehicles release three to five times more than petrol automobiles. Element emissions under urban cycles are higher than those found for on-road driving, being three or four times higher, for petrol vehicles, and two or three times, for diesel vehicles. The difference between cycles is mainly due to the high emissions for the urban cycle with hot start-up. As registered for elements, most of the PAH emissions for vehicles ≥Euro 4 were also below the detection limits. Regardless of the vehicle models or driving cycles, the two- to four-ring PAHs were always dominant. Naphthalene, with emission factors up to 925 μg km(-1), was always the most abundant PAH. The relative cancer risk associated with

  7. An investigation into the effect of a ceramic particle trap on the chemical mutagens in diesel exhaust

    SciTech Connect

    Bagley, S.T.; Dorie, L.D.; Leddy, D.G.; Johnson, J.H. )

    1987-01-01

    Diesel exhaust particles and vapor phase samples were collected from the diluted (15:1) exhaust of a 10.4 L displacement medium-duty engine (Caterpillar 3208), operated under EPA steady-state cycle Modes 4 and 5 conditions for load (50 and 75 percent, respectively) and speed (1680 rpm). Baseline (uncontrolled) emissions were compared to the exhaust modified by the use of an uncatalyzed monolithic ceramic trap (Corning). The Salmonella/microsome mutagenicity bioassay (Ames Test) was used to direct the course of chemical analyses. Total particulate matter (TPM), soluble organic fraction (SOF) (from TPM), sulfate fraction (SO4) (from TPM), and solid fraction (SOL) (from particle) were determined from dilute exhaust particles collected on 47 mm Teflon-coated woven glass fiber filters. Coincidentally, particles were collected on 508 x 508 mm Teflon-coated non-woven glass fiber filters, and vapor-phase samples were collected on XAD-2 resin. The SOF and VOC for chemical and biological characterization were obtained by Soxhlet extraction of samples with dichloromethane (DCM). Hydrocarbon mass balances were developed to evaluate the efficiency of the sampling system. Use of the ceramic traps caused no change in engine total hydrocarbon (HC) levels at Mode 4 but decreases in TPM, SOF, and NO2 were noted. In terms of HC emissions only, the percentage of SOF was significantly reduced, but the percentage of VOC was unchanged. For Mode 5, the engine HC levels were significantly reduced but the proportions of HC components, i.e. the percentage of SOF and the percentage of VOC, did not change significantly. Engine emission levels of TPM, SOF, and nitrogen dioxide were also significantly reduced at Mode 5. At both Modes 4 and 5, use of the ceramic particle traps caused an increase in the direct-acting (TA98) mutagenicity of the SOF and a decrease in the activity of the VOC.

  8. Evaluation of an exposure assessment used in epidemiological studies of diesel exhaust and lung cancer in underground mines

    PubMed Central

    Crump, Kenny; Van Landingham, Cynthia

    2012-01-01

    NIOSH/NCI (National Institute of Occupational Safety and Health and National Cancer Institute) developed exposure estimates for respirable elemental carbon (REC) as a surrogate for exposure to diesel exhaust (DE) for different jobs in eight underground mines by year beginning in the 1940s—1960s when diesel equipment was first introduced into these mines. These estimates played a key role in subsequent epidemiological analyses of the potential relationship between exposure to DE and lung cancer conducted in these mines. We report here on a reanalysis of some of the data from this exposure assessment. Because samples of REC were limited primarily to 1998–2001, NIOSH/NCI used carbon monoxide (CO) as a surrogate for REC. In addition, because CO samples were limited, particularly in the earlier years, they used the ratio of diesel horsepower (HP) to the mine air exhaust rate as a surrogate for CO. There are considerable uncertainties connected with each of these surrogate-based steps. The estimates of HP appear to involve considerable uncertainty, although we had no data upon which to evaluate the magnitude of this uncertainty. A sizable percentage (45%) of the CO samples used in the HP to CO model was below the detection limit which required NIOSH/NCI to assign CO values to these samples. In their preferred REC estimates, NIOSH/NCI assumed a linear relation between C0 and REC, although they provided no credible support for that assumption. Their assumption of a stable relationship between HP and CO also is questionable, and our reanalysis found a statistically significant relationship in only one-half of the mines. We re-estimated yearly REC exposures mainly using NIOSH/NCI methods but with some important differences: (i) rather than simply assuming a linear relationship, we used data from the mines to estimate the CO—REC relationship; (ii) we used a different method for assigning values to nondetect CO measurements; and (iii) we took account of statistical

  9. Characterization of non-exhaust coarse and fine particles from on-road driving and laboratory measurements.

    PubMed

    Kwak, Ji-hyun; Kim, Hongsuk; Lee, Janghee; Lee, Seokhwan

    2013-08-01

    We investigated the physical and chemical properties of non-exhaust coarse and fine particles generated by on-road driving and in a laboratory setting using a mobile sampling system. The on-road driving and laboratory measurements performed under constant speed driving revealed that particles produced by tire wear had a size distribution in the range of 2-3 μm, while roadway particles (RWPs) measured behind the front tire during on-road driving largely comprised crustal materials such as road surface wear particles and road dust as well as tire wear particles (TWPs). The mode diameters of particles obtained from on-road driving under cornering conditions were similar to those obtained under constant speed conditions, but with higher concentrations of crustal elements. Under braking conditions, the particulate matter (PM) concentrations of brake wear particles (BWPs) sampled near the brake pad increased significantly and were much higher than the concentration of RWPs during deceleration, indicating that BWPs are one of the main sources of non-exhaust emissions. In addition, BWPs observed from on-road and laboratory measurements had a broader PM size range (1-10 μm) than RWPs. Size-segregated chemical analysis of PM samples indicated that the concentrations of Fe and Ca were highest in the coarse fraction emitted under constant speed and cornering conditions, while Fe, Ba, and Ti were most abundant in the fine fraction emitted during braking events. PMID:23664985

  10. EXPOSURE TO CONCENTRATED AMBIENT PARTICLES (CAPS): REVIEW

    EPA Science Inventory

    Epidemiologic studies support a participation of fine particulate matter (PM) with a diameter of 0.1 to 2.5 microm in the effects of air pollution particles on human health. The ambient fine particle concentrator is a recently developed technology that can enrich the mass of ambi...

  11. Exposure to heavy charged particles affects thermoregulation in rats

    SciTech Connect

    Kandasamy, S.B.; Hunt, W.A.; Dalton, T.K.; Joseph, J.A.; Harris, A.H.; Rabin, B.M. |

    1994-09-01

    Rats exposed to 0.1-5 Gy of heavy particles ({sup 56}Fe, {sup 40}Ar, {sup 20}Ne or {sup 4}He) showed dose-dependent changes in body temperature. Lower doses of all particles produced hyperthermia, and higher doses of {sup 20}Ne and {sup 56}Fe produced hypothermia. Of the four HZE particles, {sup 56}Fe particles were the most potent and {sup 4}He particles were the least potent in producing changes in thermoregulation. The {sup 20}Ne and {sup 40}Ar particles produced an intermediate level of change in body temperature. Significantly greater hyperthermia was produced by exposure to 1 Gy of {sup 20}Ne, {sup 40}Ar and {sup 56}Fe particles than by exposure to 1 Gy of {sup 60}Co {gamma} rays. Pretreating rats with the cyclo-oxygenase inhibitor indomethacin attenuated the hyperthermia produced by exposure to 1 Gy of {sup 56}Fe particles, indicating that prostaglandins mediate {sup 56}Fe-particle-induced hyperthermia. The hypothermia produced by exposure to 5 Gy of {sup 56}Fe particles is mediated by histamine and can be attenuated by treatment with the antihistamines mepyramine and cimetidine. 15 refs., 4 figs.

  12. Inflammatory Cytokines and White Blood Cell Counts Response to Environmental Levels of Diesel Exhaust and Ozone Inhalation Exposures

    PubMed Central

    Stiegel, Matthew A.; Pleil, Joachim D.; Sobus, Jon R.; Madden, Michael C.

    2016-01-01

    Epidemiological observations of urban inhalation exposures to diesel exhaust (DE) and ozone (O3) have shown pre-clinical cardiopulmonary responses in humans. Identifying the key biological mechanisms that initiate these health bioindicators is difficult due to variability in environmental exposure in time and from person to person. Previously, environmentally controlled human exposure chambers have been used to study DE and O3 dose-response patterns separately, but investigation of co-exposures has not been performed under controlled conditions. Because a mixture is a more realistic exposure scenario for the general public, in this study we investigate the relationships of urban levels of urban-level DE exposure (300 μg/m3), O3 (0.3 ppm), DE + O3 co-exposure, and innate immune system responses. Fifteen healthy human volunteers were studied for changes in ten inflammatory cytokines (interleukins 1β, 2, 4, 5, 8, 10, 12p70 and 13, IFN-γ, and TNF-α) and counts of three white blood cell types (lymphocytes, monocytes, and neutrophils) following controlled exposures to DE, O3, and DE+O3. The results show subtle cytokines responses to the diesel-only and ozone-only exposures, and that a more complex (possibly synergistic) relationship exists in the combination of these two exposures with suppression of IL-5, IL-12p70, IFN-γ, and TNF-α that persists up to 22-hours for IFN-γ and TNF-α. The white blood cell differential counts showed significant monocyte and lymphocyte decreases and neutrophil increases following the DE + O3 exposure; lymphocytes and neutrophils changes also persist for at least 22-hours. Because human studies must be conducted under strict safety protocols at environmental levels, these effects are subtle and are generally only seen with detailed statistical analysis. This study indicates that the observed associations between environmental exposures and cardiopulmonary effects are possibly mediated by inflammatory response mechanisms. PMID:27058360

  13. Inflammatory Cytokines and White Blood Cell Counts Response to Environmental Levels of Diesel Exhaust and Ozone Inhalation Exposures.

    PubMed

    Stiegel, Matthew A; Pleil, Joachim D; Sobus, Jon R; Madden, Michael C

    2016-01-01

    Epidemiological observations of urban inhalation exposures to diesel exhaust (DE) and ozone (O3) have shown pre-clinical cardiopulmonary responses in humans. Identifying the key biological mechanisms that initiate these health bioindicators is difficult due to variability in environmental exposure in time and from person to person. Previously, environmentally controlled human exposure chambers have been used to study DE and O3 dose-response patterns separately, but investigation of co-exposures has not been performed under controlled conditions. Because a mixture is a more realistic exposure scenario for the general public, in this study we investigate the relationships of urban levels of urban-level DE exposure (300 μg/m3), O3 (0.3 ppm), DE + O3 co-exposure, and innate immune system responses. Fifteen healthy human volunteers were studied for changes in ten inflammatory cytokines (interleukins 1β, 2, 4, 5, 8, 10, 12p70 and 13, IFN-γ, and TNF-α) and counts of three white blood cell types (lymphocytes, monocytes, and neutrophils) following controlled exposures to DE, O3, and DE+O3. The results show subtle cytokines responses to the diesel-only and ozone-only exposures, and that a more complex (possibly synergistic) relationship exists in the combination of these two exposures with suppression of IL-5, IL-12p70, IFN-γ, and TNF-α that persists up to 22-hours for IFN-γ and TNF-α. The white blood cell differential counts showed significant monocyte and lymphocyte decreases and neutrophil increases following the DE + O3 exposure; lymphocytes and neutrophils changes also persist for at least 22-hours. Because human studies must be conducted under strict safety protocols at environmental levels, these effects are subtle and are generally only seen with detailed statistical analysis. This study indicates that the observed associations between environmental exposures and cardiopulmonary effects are possibly mediated by inflammatory response mechanisms. PMID:27058360

  14. Diesel Exhaust Particles Upregulate Interleukins IL-6 and IL-8 in Nasal Fibroblasts

    PubMed Central

    Park, Il-Ho; Shin, Jae-Min; Lee, Seoung-Ae; Lee, Heung-Man

    2016-01-01

    Background Diesel exhaust particles (DEP) are a major source of air pollution. Nasal fibroblasts are known to produce various cytokines and chemokines. The aim of this study was to evaluate DEP-induced cytokines and chemokines in nasal fibroblasts and to identify the signaling pathway involved. Methods A cytokine and chemokine array performed after stimulation of nasal fibroblasts with DEP revealed that levels of IL-6 and IL-8 were increased most significantly among various cytokines and chemokines. RT—PCR and ELISA were used to determine the mRNA and protein expression levels of IL-6 and IL-8. Signaling pathways of p-38, Akt, and NF-κB were analyzed by western blotting, luciferase assay, and ELISA. Organ cultures of nasal interior turbinate were also developed to demonstrate the ex vivo effect of DEP on the expression of IL-6 and IL-8 and the associated signaling pathway. Results DEP increased the expressions of IL-6 and IL-8 in nasal fibroblasts at mRNA and protein levels. DEP induced phosphorylation of p38, Akt, and NF-κB, whereas inhibitors of p38, Akt, and NF-κB blocked these phophorylations and the expressions of IL-6 and IL-8. These findings were also observed in ex vivo organ culture of nasal inferior turbinate. Conclusions DEP induces expression of IL-6 and IL-8 via p38, Akt, and NF-κB signaling pathways in nasal fibroblasts. This finding suggests that air pollution might induce or aggravate allergic rhinitis or chronic rhinosinusitis. PMID:27295300

  15. Protein kinase C-ζ mediates lung injury induced by diesel exhaust particles.

    PubMed

    Caraballo, Juan C; Borcherding, Jennifer; Thorne, Peter S; Comellas, Alejandro P

    2013-03-01

    Recently, we reported that diesel exhaust particles (DEPs) disrupt tight junctions (TJs) in alveolar epithelial cells (AECs) via an increase in reactive oxygen species (ROS). In this study, we investigated the role of protein kinase C (PKC)-ζ activation in DEP-induced lung injury. C57/bl6 mice were instilled intratracheally with 50 μl of saline containing 100 μg of DEPs or titanium dioxide (TiO2). Twenty-four hours later, bronchoalveolar lavage was performed to assess neutrophil counts and protein concentrations. In addition, in vitro experiments were performed in primary rat and human AECs exposed to DEPs (50 μg/cm(2)) for 3 hours. Transepithelial electrical conductance was measured, and TJ protein association was analyzed by immunoprecipitation. To determine whether the overexpression of antioxidants prevented DEP-induced lung injury, AECs and mice were infected with adenoviruses containing catalase and manganese superoxide dismutase (MnSOD) plasmids. In vivo, the overexpression of catalase and MnSOD prevented DEP-induced neutrophil recruitment. The inhibition of PKC-ζ activation also prevented DEP-induced neutrophil recruitment in vivo. In vitro, DEPs activated PKC-ζ in AECs, but not in alveolar macrophages. Using a specific myristolated PKC-ζ pseudosubstrate pepetide (PKC-ζ ps), we showed that PKC-ζ mediated the DEP-induced dissociation of occludin and zonula occludin-1 (ZO1) in rat and human AECs. In addition, the overexpression of constitutively active PKC-ζ induced the dissociation of occludin and ZO1 in AECs. DEP-induced TJ disruption occurs via PKC-ζ. TJ disruption seems to be in part responsible for DEP-induced lung injury. PMID:23221045

  16. Sites of particle retention and lung tissue responses to chronically inhaled diesel exhaust and coal dust in rats and cynomolgus monkeys.

    PubMed Central

    Nikula, K J; Avila, K J; Griffith, W C; Mauderly, J L

    1997-01-01

    The usefulness of pulmonary carcinogenicity data from rats exposed to high concentrations of particles for quantitatively predicting lung cancer risk in humans exposed to much lower environmental or occupational concentrations has been questioned. The results of several chronic inhalation bioassays of poorly soluble, nonfibrous particles have suggested that rats may be more prone than other rodent species to develop persistent pulmonary epithelial hyperplasia, metaplasia, and tumors in response to the accumulation of inhaled particles. In addition, rats and primates differ in their pulmonary anatomy and rate of particle clearance from the lung. This paper reviews results of recent Lovelace Respiratory Research Institute (Albuquerque, NM) investigations that directly compared the anatomical patterns of particle retention and the lung tissue responses of rats and monkeys exposed chronically to high occupational concentrations of poorly soluble particles. Lung sections from male cynomolgus monkeys and F344 rats exposed 7 hr/day, 5 days/week for 24 months to filtered ambient air, diesel exhaust (2 mg soot/m3), coal dust (2 mg respirable particulate material/m3), or diesel exhaust and coal dust combined (1 mg soot and 1 mg respirable coal dust/m3) were obtained from a study conducted at the U.S. National Institute for Occupational Safety and Health and examined histopathologically and morphometrically. Within each species, the sites of particle retention and lung tissue responses were the same for diesel soot, coal dust, and combined material. Rats retained a significantly greater portion of the particulate material in the lumens of alveolar ducts and alveoli than monkeys. Conversely, monkeys retained a significantly greater portion of the particulate material in the interstitium than rats. Rats, but not monkeys, had significant alveolar epithelial hyperplastic, inflammatory, and septal fibrotic responses to the retained particles. These results suggest that anatomic

  17. Oxidative Stress, Inflammatory and Immune Response after Inhalation Exposure to Biodiesel Exhaust

    EPA Science Inventory

    Biodiesel (BD) is an advanced fuel produced from renewable domestic sources. The broad uses of BD in different industries including mining may lead to potential health effects. We hypothesized that the toxicity of biodiesel exhaust (BDE) is dependent at least on three major mecha...

  18. NEUROPHYSIOLOGICAL ALTERATIONS DUE TO DIESEL EXHAUST EXPOSURE DURING THE NEONATAL LIFE OF THE RAT

    EPA Science Inventory

    This study was designed to assess the effects of diesel exhaust on the development of the nervous system in rats as measurably somatosensory and visual evoked potentials (SEPs an VEPs, respectively). SEPs, elicited by 1 mamp, 0.5 msec pulses delivered to the tibial nerve at the t...

  19. EFFECT OF DIESEL EXHAUST EXPOSURE ON MUCOSAL SENSITIZATION TO OVALBUMIN ANTIGEN.

    EPA Science Inventory

    Several studies in humans and animals have shown that diesel exhaust (DE) can act as an immunological adjuvant to increase the severity of Type I hypersensitivity immune responses. The mechanism by which DE causes these effects is unknown but thought to be associated with lung in...

  20. Whole and particle-free diesel exhausts differentially affect cardiac electrophysiology, blood pressure, and autonomic balance in heart failure-prone rats

    EPA Science Inventory

    Epidemiologic studies strongly link short-term exposures to vehicular traffic and particulate matter (PM) air pollution with adverse cardiovascular events, especially in those with preexisting cardiovascular disease. Diesel engine exhaust (DE) is a key contributor to urban ambien...

  1. Influential parameters on particle exposure of pedestrians in urban microenvironments

    NASA Astrophysics Data System (ADS)

    Buonanno, G.; Fuoco, F. C.; Stabile, L.

    2011-03-01

    Exposure to particle concentrations in urban areas was evaluated in several studies since airborne particles are considered to bring about adverse health effects. Transportation modes and urban microenvironments account for the highest contributions to the overall daily particle exposure concentration. In the present study an evaluation of the influential parameters affecting particle exposure of pedestrian in urban areas is reported. Street geometry, traffic mode, wind speed and direction effects were analyzed through an experimental campaign performed in different streets of an Italian town. To this purpose a high-resolution time measurement apparatus was used in order to capture the dynamic of the freshly emitted particles. Number, surface area and mass concentrations and distributions were measured continuously along both the sides of street canyons and avenue canyons during 10-minutes walking routes. The combined effect of street geometry and wind direction may contribute strongly to dilute the fresh particles emitted by vehicles. In particular, street canyons are characterized by lower ventilation phenomena which lead to similar concentration values on both the side of the street. Higher wind speed was found to decrease concentrations in the canyon. Traffic mode also seems to influence exposure concentrations. In particular, submicrometer particle mass concentration was higher as the traffic is more congested; otherwise, coarse fraction dominates mass exposure concentration along street characterized by a more fluent traffic, showing a typical resuspension modality.

  2. Human visual response to nuclear particle exposures

    NASA Technical Reports Server (NTRS)

    Tobias, C. A.; Budinger, T. F.; Lyman, J. T.

    1972-01-01

    Experiments with accelerated helium ions were performed in an effort to localize the site of initial radiation interactions in the eye that lead to light flash observations by astronauts during spaceflight. The character and efficiency of helium ion induction of visual sensations depended on the state of dark adaptation of the retina; also, the same events were seen with different efficiencies and details when particle flux density changed. It was concluded that fast particles cause interactions in the retina, particularly in the receptor layer, and thus give rise to the sensations of light flashes, streaks, and supernovae.

  3. In Vitro Exposures in Diesel Exhaust Atmospheres: Resuspension of PM from Filters Verses Direct Deposition of PM from Air

    PubMed Central

    Lichtveld, Kim M.; Ebersviller, Seth M.; Sexton, Kenneth G.; Vizuete, William; Jaspers, Ilona; Jeffries, Harvey E.

    2012-01-01

    One of the most widely used in vitro particulate matter (PM) exposures methods is the collection of PM on filters, followed by resuspension in a liquid medium, with subsequent addition onto a cell culture. To avoid disruption of equilibria between gases and PM, we have developed a direct in vitro sampling and exposure method (DSEM) capable of PM-only exposures. We hypothesize that the separation of phases and post-treatment of filter-collected PM significantly modifies the toxicity of the PM compared to direct deposition, resulting in a distorted view of the potential PM health effects. Controlled test environments were created in a chamber that combined diesel exhaust with an urban-like mixture. The complex mixture was analyzed using both the DSEM and concurrently-collected filter samples. The DSEM showed that PM from test atmospheres produced significant inflammatory response, while the resuspension exposures at the same exposure concentration did not. Increasing the concentration of resuspended PM sixteen times was required to yield measurable IL-8 expression. Chemical analysis of the resuspended PM indicated a total absence of carbonyl compounds compared to the test atmosphere during the direct-exposures. Therefore, collection and resuspension of PM into liquid modifies its toxicity and likely leads to underestimating toxicity. PMID:22834915

  4. Long-Term Effects of Diesel Exhaust Particles on Airway Inflammation and Remodeling in a Mouse Model

    PubMed Central

    Kim, Byeong-Gon; Lee, Pureun-Haneul; Lee, Shin-Hwa; Kim, Young-En; Shin, Mee-Yong; Kang, Yena; Bae, Seong-Hwan; Kim, Min-Jung; Rhim, TaiYoun; Park, Choon-Sik

    2016-01-01

    Purpose Diesel exhaust particles (DEPs) can induce and trigger airway hyperresponsiveness (AHR) and inflammation. The aim of this study was to investigate the effect of long-term DEP exposure on AHR, inflammation, lung fibrosis, and goblet cell hyperplasia in a mouse model. Methods BALB/c mice were exposed to DEPs 1 hour a day for 5 days a week for 3 months in a closed-system chamber attached to a ultrasonic nebulizer (low dose: 100 µg/m3 DEPs, high dose: 3 mg/m3 DEPs). The control group was exposed to saline. Enhanced pause was measured as an indicator of AHR. Animals were subjected to whole-body plethysmography and then sacrificed to determine the performance of bronchoalveolar lavage and histology. Results AHR was higher in the DEP group than in the control group, and higher in the high-dose DEP than in the low-dose DEP groups at 4, 8, and 12 weeks. The numbers of neutrophils and lymphocytes were higher in the high-dose DEP group than in the low-dose DEP group and control group at 4, 8, and 12 weeks. The levels of interleukin (IL)-5, IL-13, and interferon-γ were higher in the low-dose DEP group than in the control group at 12 weeks. The level of IL-10 was higher in the high-dose DEP group than in the control group at 12 weeks. The level of vascular endothelial growth factor was higher in the low-dose and high-dose DEP groups than in the control group at 12 weeks. The level of IL-6 was higher in the low-dose DEP group than in the control group at 12 weeks. The level of transforming growth factor-β was higher in the high-dose DEP group than in the control group at 4, 8, and 12 weeks. The collagen content and lung fibrosis in lung tissue was higher in the high-dose DEP group at 8 and 12 weeks. Conclusions These results suggest that long-term DEP exposure may increase AHR, inflammation, lung fibrosis, and goblet cell hyperplasia in a mouse model. PMID:26922935

  5. New Methods for Personal Exposure Monitoring for Airborne Particles.

    PubMed

    Koehler, Kirsten A; Peters, Thomas M

    2015-12-01

    Airborne particles have been associated with a range of adverse cardiopulmonary outcomes, which has driven its monitoring at stationary central sites throughout the world. Individual exposures, however, can differ substantially from concentrations measured at central sites due to spatial variability across a region and sources unique to the individual, such as cooking or cleaning in homes, traffic emissions during commutes, and widely varying sources encountered at work. Personal monitoring with small, battery-powered instruments enables the measurement of an individual's exposure as they go about their daily activities. Personal monitoring can substantially reduce exposure misclassification and improve the power to detect relationships between particulate pollution and adverse health outcomes. By partitioning exposures to known locations and sources, it may be possible to account for variable toxicity of different sources. This review outlines recent advances in the field of personal exposure assessment for particulate pollution. Advances in battery technology have improved the feasibility of 24-h monitoring, providing the ability to more completely attribute exposures to microenvironment (e.g., work, home, commute). New metrics to evaluate the relationship between particulate matter and health are also being considered, including particle number concentration, particle composition measures, and particle oxidative load. Such metrics provide opportunities to develop more precise associations between airborne particles and health and may provide opportunities for more effective regulations. PMID:26385477

  6. New Methods for Personal Exposure Monitoring for Airborne Particles

    PubMed Central

    Koehler, Kirsten A.; Peters, Thomas

    2016-01-01

    Airborne particles have been associated with a range of adverse cardiopulmonary outcomes, which has driven its monitoring at stationary, central sites throughout the world. Individual exposures, however, can differ substantially from concentrations measured at central sites due to spatial variability across a region and sources unique to the individual, such as cooking or cleaning in homes, traffic emissions during commutes, and widely varying sources encountered at work. Personal monitoring with small, battery-powered instruments enables the measurement of an individual’s exposure as they go about their daily activities. Personal monitoring can substantially reduce exposure misclassification and improve the power to detect relationships between particulate pollution and adverse health outcomes. By partitioning exposures to known locations and sources, it may be possible to account for variable toxicity of different sources. This review outlines recent advances in the field of personal exposure assessment for particulate pollution. Advances in battery technology have improved the feasibility of 24-hour monitoring, providing the ability to more completely attribute exposures to microenvironment (e.g., work, home, commute). New metrics to evaluate the relationship between particulate matter and health are also being considered, including particle number concentration, particle composition measures, and particle oxidative load. Such metrics provide opportunities to develop more precise associations between airborne particles and health and may provide opportunities for more effective regulations. PMID:26385477

  7. Ultrafine and respirable particle exposure during vehicle fire suppression

    PubMed Central

    Fent, Kenneth W.

    2015-01-01

    Vehicle fires are a common occurrence, yet few studies have reported exposures associated with burning vehicles. This article presents an assessment of firefighters’ potential for ultrafine and respirable particle exposure during vehicle fire suppression training. Fires were initiated within the engine compartment and passenger cabins of three salvaged vehicles, with subsequent water suppression by fire crews. Firefighter exposures were monitored with an array of direct reading particle and air quality instruments. A flexible metallic duct and blower drew contaminants to the instrument array, positioned at a safe distance from the burning vehicles, with the duct inlet positioned at the nozzle operator’s shoulder. The instruments measured the particle number, active surface area, respirable particle mass, photoelectric response, aerodynamic particle size distributions, and air quality parameters. Although vehicle fires were suppressed quickly (<10 minutes), firefighters may be exposed to short duration, high particle concentration episodes during fire suppression, which are orders of magnitude greater than the ambient background concentration. A maximum transient particle concentration of 1.21 × 107 particles per cm3, 170 mg m−3 respirable particle mass, 4700 μm2 cm−3 active surface area and 1400 (arbitrary units) in photoelectric response were attained throughout the series of six fires. Expressed as fifteen minute time-weighted averages, engine compartment fires averaged 5.4 × 104 particles per cm3, 0.36 mg m−3 respirable particle mass, 92 μm2 cm−3 active particle surface area and 29 (arbitrary units) in photoelectric response. Similarly, passenger cabin fires averaged 2.04 × 105 particles per cm3, 2.7 mg m−3 respirable particle mass, 320 μm2 cm−3 active particle surface area, and 34 (arbitrary units) in photoelectric response. Passenger cabin fires were a greater potential source of exposure than engine compartment fires. The wind direction

  8. Ultrafine and respirable particle exposure during vehicle fire suppression.

    PubMed

    Evans, Douglas E; Fent, Kenneth W

    2015-10-01

    Vehicle fires are a common occurrence, yet few studies have reported exposures associated with burning vehicles. This article presents an assessment of firefighters' potential for ultrafine and respirable particle exposure during vehicle fire suppression training. Fires were initiated within the engine compartment and passenger cabins of three salvaged vehicles, with subsequent water suppression by fire crews. Firefighter exposures were monitored with an array of direct reading particle and air quality instruments. A flexible metallic duct and blower drew contaminants to the instrument array, positioned at a safe distance from the burning vehicles, with the duct inlet positioned at the nozzle operator's shoulder. The instruments measured the particle number, active surface area, respirable particle mass, photoelectric response, aerodynamic particle size distributions, and air quality parameters. Although vehicle fires were suppressed quickly (<10 minutes), firefighters may be exposed to short duration, high particle concentration episodes during fire suppression, which are orders of magnitude greater than the ambient background concentration. A maximum transient particle concentration of 1.21 × 10(7) particles per cm(3), 170 mg m(-3) respirable particle mass, 4700 μm(2) cm(-3) active surface area and 1400 (arbitrary units) in photoelectric response were attained throughout the series of six fires. Expressed as fifteen minute time-weighted averages, engine compartment fires averaged 5.4 × 10(4) particles per cm(3), 0.36 mg m(-3) respirable particle mass, 92 μm(2) cm(-3) active particle surface area and 29 (arbitrary units) in photoelectric response. Similarly, passenger cabin fires averaged 2.04 × 10(5) particles per cm(3), 2.7 mg m(-3) respirable particle mass, 320 μm(2) cm(-3) active particle surface area, and 34 (arbitrary units) in photoelectric response. Passenger cabin fires were a greater potential source of exposure than engine compartment fires. The

  9. Ultrafine particles: exposure and source apportionment in 56 Danish homes.

    PubMed

    Bekö, Gabriel; Weschler, Charles J; Wierzbicka, Aneta; Karottki, Dorina Gabriela; Toftum, Jørn; Loft, Steffen; Clausen, Geo

    2013-09-17

    Particle number (PN) concentrations (10-300 nm in size) were continuously measured over a period of ~45 h in 56 residences of nonsmokers in Copenhagen, Denmark. The highest concentrations were measured when occupants were present and awake (geometric mean, GM: 22.3 × 10(3) cm(-3)), the lowest when the homes were vacant (GM: 6.1 × 10(3) cm(-3)) or the occupants were asleep (GM: 5.1 × 10(3) cm(-3)). Diary entries regarding occupancy and particle related activities were used to identify source events and apportion the daily integrated exposure among sources. Source events clearly resulted in increased PN concentrations and decreased average particle diameter. For a given event, elevated particle concentrations persisted for several hours after the emission of fresh particles ceased. The residential daily integrated PN exposure in the 56 homes ranged between 37 × 10(3) and 6.0 × 10(6) particles per cm(3)·h/day (GM: 3.3 × 10(5) cm(-3)·h/day). On average, ~90% of this exposure occurred outside of the period from midnight to 6 a.m. Source events, especially candle burning, cooking, toasting, and unknown activities, were responsible on average for ~65% of the residential integrated exposure (51% without the unknown activities). Candle burning occurred in half of the homes where, on average, it was responsible for almost 60% of the integrated exposure. PMID:23957328

  10. Exposure-Response Estimates for Diesel Engine Exhaust and Lung Cancer Mortality Based on Data from Three Occupational Cohorts

    PubMed Central

    Silverman, Debra T.; Garshick, Eric; Vlaanderen, Jelle; Portengen, Lützen; Steenland, Kyle

    2013-01-01

    Background: Diesel engine exhaust (DEE) has recently been classified as a known human carcinogen. Objective: We derived a meta-exposure–response curve (ERC) for DEE and lung cancer mortality and estimated lifetime excess risks (ELRs) of lung cancer mortality based on assumed occupational and environmental exposure scenarios. Methods: We conducted a meta-regression of lung cancer mortality and cumulative exposure to elemental carbon (EC), a proxy measure of DEE, based on relative risk (RR) estimates reported by three large occupational cohort studies (including two studies of workers in the trucking industry and one study of miners). Based on the derived risk function, we calculated ELRs for several lifetime occupational and environmental exposure scenarios and also calculated the fractions of annual lung cancer deaths attributable to DEE. Results: We estimated a lnRR of 0.00098 (95% CI: 0.00055, 0.0014) for lung cancer mortality with each 1-μg/m3-year increase in cumulative EC based on a linear meta-regression model. Corresponding lnRRs for the individual studies ranged from 0.00061 to 0.0012. Estimated numbers of excess lung cancer deaths through 80 years of age for lifetime occupational exposures of 1, 10, and 25 μg/m3 EC were 17, 200, and 689 per 10,000, respectively. For lifetime environmental exposure to 0.8 μg/m3 EC, we estimated 21 excess lung cancer deaths per 10,000. Based on broad assumptions regarding past occupational and environmental exposures, we estimated that approximately 6% of annual lung cancer deaths may be due to DEE exposure. Conclusions: Combined data from three U.S. occupational cohort studies suggest that DEE at levels common in the workplace and in outdoor air appear to pose substantial excess lifetime risks of lung cancer, above the usually acceptable limits in the United States and Europe, which are generally set at 1/1,000 and 1/100,000 based on lifetime exposure for the occupational and general population, respectively. Citation

  11. Gluthathione-S-transferase M1 regulation of diesel exhaust particle-induced pro-inflammatory mediator expression in normal human bronchial epithelial cells

    EPA Science Inventory

    Diesel exhaust particles (DEP) contribute substantially to ambient particulate matter (PM) air pollution in urban areas. Inhalation of PM has been associated with increased incidence of lung disease in susceptible populations. We have demonstrated that the glutathione-S-transfera...

  12. Effects of an iron-based fuel-borne catalyst and a diesel particle filter on exhaust toxicity in lung cells in vitro.

    PubMed

    Steiner, Sandro; Czerwinski, Jan; Comte, Pierre; Heeb, Norbert V; Mayer, Andreas; Petri-Fink, Alke; Rothen-Rutishauser, Barbara

    2015-08-01

    Metal-containing fuel additives catalyzing soot combustion in diesel particle filters are used in a widespread manner, and with the growing popularity of diesel vehicles, their application is expected to increase in the near future. Detailed investigation into how such additives affect exhaust toxicity is therefore necessary and has to be performed before epidemiological evidence points towards adverse effects of their application. The present study investigates how the addition of an iron-based fuel additive (Satacen®3, 40 ppm Fe) to low-sulfur diesel affects the in vitro cytotoxic, oxidative, (pro-)inflammatory, and mutagenic activity of the exhaust of a passenger car operated under constant, low-load conditions by exposing a three-dimensional model of the human airway epithelium to complete exhaust at the air-liquid interface. We could show that the use of the iron catalyst without and with filter technology has positive as well as negative effects on exhaust toxicity compared to exhaust with no additives: it decreases the oxidative and, compared to a non-catalyzed diesel particle filter, the mutagenic potential of diesel exhaust, but increases (pro-)inflammatory effects. The presence of a diesel particle filter also influences the impact of Satacen®3 on exhaust toxicity, and the proper choice of the filter type to be used is of importance with regards to exhaust toxicity. Figure ᅟ. PMID:24880869

  13. Isolation and Quantitative Estimation of Diesel Exhaust and Carbon Black Particles Ingested by Lung Epithelial Cells and Alveolar Macrophages In Vitro

    EPA Science Inventory

    A new procedure for isolating and estimating ingested carbonaceous diesel exhaust particles (DEP) or carbon black (CB) particles by lung epithelial cells and macrophages is described. Cells were incubated with DEP or CB to examine cell-particle interaction and ingestion. After va...

  14. Exposure visualisation of ultrafine particle counts in a transport microenvironment

    NASA Astrophysics Data System (ADS)

    Kaur, S.; Clark, R. D. R.; Walsh, P. T.; Arnold, S. J.; Colvile, R. N.; Nieuwenhuijsen, M. J.

    An increasing number of studies indicate that short-term peak exposures, such as those seen in the transport microenvironment, pose particular health threats. Short-term exposure can only be sufficiently characterised using portable, fast-response monitoring instrumentation with detailed summaries of individual activity. In this paper, we present an exposure visualisation system that addresses this issue—it allows the simultaneous presentation of mobile video imagery synchronised with measured real-time ultrafine particle count exposure of an individual. The combined data can be examined in detail for the contribution of the surrounding environment and the individual's activities to their peak and overall exposure. The exposure visualisation system is demonstrated and evaluated around the DAPPLE study site in Central London using different modes of transport (walking, cycling, bus, car and taxi). The video images, synchronised with the exposure profile, highlight the extent to which ultrafine particle exposure is associated with traffic density and proximity to pollutant source. The extremely rapid decline in concentration with increasing distance away from the pollutant source, such as from the main street to the backstreets, is clearly evident. The visualisation technique allows these data to be presented to both technical audiences and laypersons thus making it an effective environmental risk communication tool. Some exposure peaks however are not obviously associated with any event recorded on video—in these cases it will be necessary to use advanced dispersion modelling techniques to investigate meteorological conditions and other variables influencing in-street conditions to identify their possible causes.

  15. Characterization of particle exposure in ferrochromium and stainless steel production.

    PubMed

    Järvelä, Merja; Huvinen, Markku; Viitanen, Anna-Kaisa; Kanerva, Tomi; Vanhala, Esa; Uitti, Jukka; Koivisto, Antti J; Junttila, Sakari; Luukkonen, Ritva; Tuomi, Timo

    2016-07-01

    This study describes workers' exposure to fine and ultrafine particles in the production chain of ferrochromium and stainless steel during sintering, ferrochromium smelting, stainless steel melting, and hot and cold rolling operations. Workers' personal exposure to inhalable dust was assessed using IOM sampler with a cellulose acetate filter (AAWP, diameter 25 mm; Millipore, Bedford, MA). Filter sampling methods were used to measure particle mass concentrations in fixed locations. Particle number concentrations and size distributions were examined using an SMPS+C sequential mobile particle sizer and counter (series 5.400, Grimm Aerosol Technik, Ainring, Germany), and a hand-held condensation particle counter (CPC, model 3007, TSI Incorporated, MN). The structure and elemental composition of particles were analyzed using TEM-EDXA (TEM: JEM-1220, JEOL, Tokyo, Japan; EDXA: Noran System Six, Thermo Fisher Scientific Inc., Madison,WI). Workers' personal exposure to inhalable dust averaged 1.87, 1.40, 2.34, 0.30, and 0.17 mg m(-3) in sintering plant, ferrochromium smelter, stainless steel melting shop, hot rolling mill, and the cold rolling mill, respectively. Particle number concentrations measured using SMPS+C varied from 58 × 10(3) to 662 × 10(3) cm(-3) in the production areas, whereas concentrations measured using SMPS+C and CPC3007 in control rooms ranged from 24 × 10(3) to 243 × 10(3) cm(-3) and 5.1 × 10(3) to 97 × 10(3) cm(-3), respectively. The elemental composition and the structure of particles in different production phases varied. In the cold-rolling mill non-process particles were abundant. In other sites, chromium and iron originating from ore and recycled steel scrap were the most common elements in the particles studied. Particle mass concentrations were at the same level as that reported earlier. However, particle number measurements showed a high amount of ultrafine particles, especially in sintering, alloy smelting and melting, and tapping

  16. Xenobiotic Particle Exposure and Microvascular Endpoints: A Call to Arms

    PubMed Central

    Stapleton, Phoebe A.; Minarchick, Valerie C.; McCawley, Michael; Knuckles, Travis L.; Nurkiewicz, Timothy R.

    2011-01-01

    Xenobiotic particles can be considered in two genres: air pollution particulate matter and engineered nanoparticles. Particle exposures can occur in the greater environment, the workplace, and our homes. The majority of research in this field has, justifiably, focused on pulmonary reactions and outcomes. More recent investigations indicate that cardiovascular effects are capable of correlating with established mortality and morbidity epidemiological data following particle exposures. While the preliminary and general cardiovascular toxicology has been defined, the mechanisms behind these effects, specifically within the microcirculation, are largely unexplored. Therefore, the purpose of this review is several fold: first, a historical background on toxicological aspects of particle research is presented. Second, essential definitions, terminology, and techniques that may be unfamiliar to the microvascular scientist will be discussed. Third, the most current concepts and hypotheses driving cardiovascular research in this field will be reviewed. Lastly, potential future directions for the microvascular scientist will be suggested. Collectively speaking, microvascular research in the particle exposure field represents far more than a “niche”. The immediate demand for basic, translational, and clinical studies is high and diverse. Microvascular scientists at all career stages are strongly encouraged to expand their research interests to include investigations associated with particle exposures. PMID:21951337

  17. In utero and early life exposure to diesel exhaust air pollution increases adult susceptibility to heart failure in mice

    PubMed Central

    2013-01-01

    Background Fine particulate air pollution (PM2.5) is a global health concern, as exposure to PM2.5 has consistently been found to be associated with increased cardiovascular morbidity and mortality. Although adult exposure to traffic related PM2.5, which is largely derived from diesel exhaust (DE), has been associated with increased cardiac hypertrophy, there are limited investigations into the potential effect of in utero and early life exposure on adult susceptibility to heart disease. In this study, we investigate the effect of in utero and early life exposure to DE on adult susceptibility to heart failure. Methods Female C57BL/6 J mice were exposed to either filtered air (FA) or DE for 3 weeks (≈300 μg/m3 PM2.5 for 6 hours/day, 5 days/week) and then introduced to male breeders for timed matings. Female mice were exposed to either FA or DE throughout pregnancy and until offspring were 3 weeks of age. Offspring were then transferred to either FA or DE for an additional 8 weeks of exposure. At 12 weeks of age, male offspring underwent a baseline echocardiographic assessment, followed by a sham or transverse aortic constriction (TAC) surgery to induce pressure overload. Following sacrifice three weeks post surgery, ventricles were processed for histology to assess myocardial fibrosis and individual cardiomyocyte hypertrophy. mRNA from lung tissue was isolated to measure expression of inflammatory cytokines IL6 and TNFα. Results We observed that mice exposed to DE during in utero and early life development have significantly increased susceptibility to cardiac hypertrophy, systolic failure, myocardial fibrosis, and pulmonary congestion following TAC surgery compared to FA control, or adult DE exposed mice. In utero and early life DE exposure also strongly modified the inflammatory cytokine response in the adult lung. Conclusions We conclude that exposure to diesel exhaust air pollution during in utero and early life development in mice increases adult

  18. Exposure to diesel exhaust up-regulates iNOS expression in ApoE knockout mice

    SciTech Connect

    Bai Ni; Kido, Takashi; Kavanagh, Terrance J.; Kaufman, Joel D.; Rosenfeld, Michael E.; Breemen, Cornelis van; Eeden, Stephan F. van

    2011-09-01

    Traffic related particulate matter air pollution is a risk factor for cardiovascular events; however, the biological mechanisms are unclear. We hypothesize that diesel exhaust (DE) inhalation induces up-regulation of inducible nitric oxide synthase (iNOS), which is known to contribute to vascular dysfunction, progression of atherosclerosis and ultimately cardiovascular morbidity and mortality. Methods: ApoE knockout mice (30-week) were exposed to DE (at 200 {mu}g/m{sup 3} of particulate matter) or filtered-air (control) for 7 weeks (6 h/day, 5 days/week). iNOS expression in the blood vessels and heart was evaluated by immunohistochemistry and western blotting analysis. To examine iNOS activity, thoracic aortae were mounted in a wire myograph, and vasoconstriction stimulated by phenylephrine (PE) was measured with and without the presence of the specific inhibitor for iNOS (1400 W). NF-{kappa}B (p65) activity was examined by ELISA. The mRNA expression of iNOS and NF-{kappa}B (p65) was determined by real-time PCR. Results: DE exposure significantly enhanced iNOS expression in the thoracic aorta (4-fold) and heart (1.5 fold). DE exposure significantly attenuated PE-stimulated vasoconstriction by {approx} 20%, which was partly reversed by 1400 W. The mRNA expression of iNOS and NF-{kappa}B was significantly augmented after DE exposure. NF-{kappa}B activity was enhanced 2-fold after DE inhalation, and the augmented NF-{kappa}B activity was positively correlated with iNOS expression (R{sup 2} = 0.5998). Conclusions: We show that exposure to DE increases iNOS expression and activity possibly via NF-{kappa}B-mediated pathway. We suspect that DE exposure-caused up-regulation of iNOS contributes to vascular dysfunction and atherogenesis, which could ultimately lead to urban air pollution-associated cardiovascular morbidity and mortality. - Highlights: > Exposed ApoE knockout mice (30-week) to diesel exhaust (DE) for 7 weeks. > Examine iNOS expression and activity in the

  19. DNA adducts induced by in vitro activation of extracts of diesel and biodiesel exhaust particles

    EPA Science Inventory

    AbstractContext: Biodiesel and biodiesel-blend fuels offer a renewable alternative to petroleum diesel, but few data are available concerning the carcinogenic potential of biodiesel exhausts. Objectives: We compared the formation of covalent DNA adducts by the in vitro metabol...

  20. Divergent Electrocardiographic Responses to Whole and Particle-Free Diesel Exhaust Inhalation in Spontaneously Hypertensive Rats

    EPA Science Inventory

    Diesel exhaust (DE) is a major contributor to traffic-related fine PM2.5. While inroads have been made in understanding the mechanisms of PM related health effects, DE’s complex mixture of PM, gases and volatile organics makes it difficult to determine how the constituents contri...

  1. A NOVEL TECHNIQUE FOR QUANTITATIVE ESTIMATION OF UPTAKE OF DIESEL EXHAUST PARTICLES BY LUNG CELLS

    EPA Science Inventory

    While airborne particulates like diesel exhaust particulates (DEP) exert significant toxicological effects on lungs, quantitative estimation of accumulation of DEP inside lung cells has not been reported due to a lack of an accurate and quantitative technique for this purpose. I...

  2. REDUCING DIESEL NOX AND SOOT EMISSIONS VIA PARTICLE-FREE EXHAUST GAS RECIRCULATION - PHASE I

    EPA Science Inventory

    Diesel engines play an important role in the United States economy for power generation and transportation. However, NOx and soot emissions from both stationary and mobile diesel engines are a major contributor to air pollution. Many engine modifications and exhaust-after-t...

  3. Charged particle radiation exposure of geocentric satellites

    NASA Technical Reports Server (NTRS)

    Stassinopoulos, E. G.

    1989-01-01

    The near-earth radiation environment is characterized, summarizing published data on trapped and transient charged particles and their potential effects on hardware systems and the crews of manned missions. Topics examined include the role of the magnetosphere, the five radiation domains, cyclic and sporadic variations in the radiation environment, the potential effect of a high-altitude nuclear explosion, NASA empirical models for predicting trapped proton and electron fluxes, and the South Atlantic anomaly and the estimation of flux-free periods. Consideration is given to solar cosmic rays and heavy ions, Galactic cosmic rays, geomagnetic shielding, secondary radiation, the design of shielding systems, variables affecting dose evaluations, and ionizing-radiation doses. Extensive diagrams, graphs, and tables of numerical data are provided.

  4. Occupational Exposure to Respirable Dust, Respirable Crystalline Silica and Diesel Engine Exhaust Emissions in the London Tunnelling Environment.

    PubMed

    Galea, Karen S; Mair, Craig; Alexander, Carla; de Vocht, Frank; van Tongeren, Martie

    2016-03-01

    Personal 8-h shift exposure to respirable dust, diesel engine exhaust emissions (DEEE) (as respirable elemental carbon), and respirable crystalline silica of workers involved in constructing an underground metro railway tunnel was assessed. Black carbon (BC) concentrations were also assessed using a MicroAeth AE51. During sprayed concrete lining (SCL) activities in the tunnel, the geometric mean (GM) respirable dust exposure level was 0.91mg m(-3), with the highest exposure measured on a back-up sprayer (3.20mg m(-3)). The GM respirable crystalline silica concentration for SCL workers was 0.03mg m(-3), with the highest measurement also for the back-up sprayer (0.24mg m(-3)). During tunnel boring machine (TBM) activities, the GM respirable dust concentration was 0.54mg m(-3). The GM respirable elemental carbon concentration for all the TBM operators was 18 µg m(-3); with the highest concentration measured on a segment lifter. The BC concentrations were higher in the SCL environment in comparison to the TBM environment (daily GM 18-54 µg m(-3) versus 3-6 µg m(-3)). This small-scale monitoring campaign provides additional personal data on exposures experienced by underground tunnel construction workers. PMID:26403363

  5. Vehicular Exhaust Particles Promote Allergic Airway Inflammation via an Aryl Hydrocarbon Receptor-Notch Signaling Cascade

    PubMed Central

    Xia, Mingcan; Viera-Hutchins, Loida; Garcia-Lloret, Maria; Rivas, Magali Noval; Wise, Petra; MGhee, Sean A.; Chatila, Zena K.; Daher, Nancy; Sioutas, Constantinos; Chatila, Talal A.

    2015-01-01

    Background Traffic-related particulate matter (PM) has been linked to heightened incidence of asthma and allergic diseases. However, molecular mechanisms by which PM exposure promote allergic diseases remain elusive. Objective We sought to determine the expression, function and regulation of pathways involved in the promotion by PM of allergic airway inflammation. Methods We employed gene expression transcriptional profiling, in vitro culture assays, and vivo murine models of allergic airway inflammation. Results We identified genes of the Notch pathway, most notably Jagged 1 (Jag1), as targets of PM induction in human monocytes and murine dendritic cells (DCs). PM, especially ultrafine particles (UFP), upregulated T helper cytokine, IgE production and allergic airway inflammation in mice in a Jag1 and Notch-dependent manner especially in the context of the pro-asthmatic IL-4 receptor allele Il4raR576. PM-induced Jag1 expression was mediated by the aryl hydrocarbon receptor (AhR), which bound to and activated AhR response elements in the Jag1 promoter. Pharmacological antagonism of AhR or its lineage-specific deletion in CD11c+ cells abrogated the augmentation of airway inflammation by PM. Conclusion PM activate an AhR-Jag1-Notch cascade to promote allergic airway inflammation in concert with pro-asthmatic alleles. PMID:25825216

  6. Constraints on Exposure Ages of Lunar and Asteroidal Regolith Particles

    NASA Technical Reports Server (NTRS)

    Berger, Eve L.; Keller, Lindsay P

    2014-01-01

    Mineral grains in lunar and asteroidal regolith samples provide a unique record of their interaction with the space environment. Exposure to the solar wind results in implantation effects that are preserved in the rims of grains (typically the outermost 100 nm), while impact processes result in the accumulation of vapor-deposited elements, impact melts and adhering grains on particle surfaces. These processes are collectively referred to as space weathering. A critical element in the study of these processes is to determine the rate at which these effects accumulate in the grains during their space exposure. For small particulate samples, one can use the density of solar flare particle tracks to infer the length of time the particle was at the regolith surface (i.e., its exposure age). We have developed a new technique that enables more accurate determination of solar flare particle track densities in mineral grains <50 micron in size that utilizes focused ion beam (FIB) sample preparation combined with transmission electron microscopy (TEM) imaging. We have applied this technique to lunar soil grains from the Apollo 16 site (soil 64501) and most recently to samples from asteroid 25143 Itokawa returned by the Hayabusa mission. Our preliminary results show that the Hayabusa grains have shorter exposure ages compared to typical lunar soil grains. We will use these techniques to re-examine the track density-exposure age calibration from lunar samples reported by Blanford et al. (1975).

  7. Analysis of the effects of meteorology on aircraft exhaust dispersion and deposition using a Lagrangian particle model.

    PubMed

    Pecorari, Eliana; Mantovani, Alice; Franceschini, Chiara; Bassano, Davide; Palmeri, Luca; Rampazzo, Giancarlo

    2016-01-15

    The risk of air quality degradation is of considerable concern particularly for those airports that are located near urban areas. The ability to quantitatively predict the effects of air pollutants originated by airport operations is important for assessing air quality and the related impacts on human health. Current emission regulations have focused on local air quality in the proximity of airports. However, an integrated study should consider the effects of meteorological events, at both regional and local level, that can affect the dispersion and the deposition of exhausts. Rigorous scientific studies and extensive experimental data could contribute to the analysis of the impacts of airports expansion plans. This paper is focused on the analysis of the effects of meteorology on aircraft emission for the Marco Polo Airport in Venice. This is the most important international airport in the eastern part of the Po' Valley, one of the most polluted area in Europe. Air pollution is exacerbated by meteorology that is a combination of large and local scale effects that do not allow significant dispersion. Moreover, the airport is located near Venice, a city of noteworthy cultural and architectural relevance, and nearby the lagoon that hosts several areas of outstanding ecological importance at European level (Natura 2000 sites). Dispersion and deposit of the main aircraft exhausts (NOx, HC and CO) have been evaluated by using a Lagrangian particle model. Spatial and temporal aircraft exhaust dispersion has been analyzed for LTO cycle. Aircraft taxiing resulted to be the most impacting aircraft operation especially for the airport working area and its surroundings, however occasionally peaks may be observed even at high altitudes when cruise mode starts. Mixing height can affect concentrations more significantly than the concentrations in the exhausts themselves. An increase of HC and CO concentrations (15-50%) has been observed during specific meteorological events

  8. Exhaust particle and NOx emission performance of an SCR heavy duty truck operating in real-world conditions

    NASA Astrophysics Data System (ADS)

    Saari, Sampo; Karjalainen, Panu; Ntziachristos, Leonidas; Pirjola, Liisa; Matilainen, Pekka; Keskinen, Jorma; Rönkkö, Topi

    2016-02-01

    Particle and NOx emissions of an SCR equipped HDD truck were studied in real-world driving conditions using the "Sniffer" mobile laboratory. Real-time CO2 measurement enables emission factor calculation for NOx and particles. In this study, we compared three different emission factor calculation methods and characterised their suitability for real-world chasing experiments. The particle number emission was bimodal and dominated by the nucleation mode particles (diameter below 23 nm) having emission factor up to 1 × 1015 #/kgfuel whereas emission factor for soot (diameter above 23 nm that is consistent with the PMP standard) was typically 1 × 1014 #/kgfuel. The effect of thermodenuder on the exhaust particles indicated that the nucleation particles consisted mainly of volatile compounds, but sometimes there also existed a non-volatile core. The nucleation mode particles are not controlled by current regulations in Europe. However, these particles consistently form under atmospheric dilution in the plume of the truck and constitute a health risk for the human population that is exposed to those. Average NOx emission was 3.55 g/kWh during the test, whereas the Euro IV emission limit over transient testing is 3.5 g NOx/kWh. The on-road emission performance of the vehicle was very close to the expected levels, confirming the successful operation of the SCR system of the tested vehicle. Heavy driving conditions such as uphill driving increased both the NOx and particle number emission factors whereas the emission factor for soot particle number remains rather constant.

  9. A comparison of sampling and analytical methods for assessing occupational exposure to diesel exhaust in a railroad work environment.

    PubMed

    Verma, D K; Shaw, L; Julian, J; Smolynec, K; Wood, C; Shaw, D

    1999-10-01

    Methods of assessing occupational exposure to diesel exhaust were evaluated in a railroad work environment. The American Conference of Governmental Industrial Hygienists (ACGIH)-recommended elemental carbon and respirable combustible dust methods of sampling and analysis for assessing diesel exhaust were included in the study. A total of 215 personal and area samples were collected using both size-selective (nylon cyclone and Marple) and non-size-selective samplers. The results demonstrate that the elemental carbon method is suitable for the railroad environment and the respirable combustible dust method is not. All elemental carbon concentrations measured were below the proposed ACGIH Threshold Limit Value (TLV) of 0.15 mg/m3. The concentrations of oxides of nitrogen (nitric oxide and nitrogen dioxide) were also found to be below their respective TLVs. There is no correlation between elemental carbon or respirable combustible dust and the oxides of nitrogen. The elemental carbon as fraction of total carbon is about 13 percent, except for onboard locomotives where it is about 24 percent. Comparison of elemental carbon and respirable combustible dust measurements showed consistent relationships for most sampling locations, with respirable combustible dust concentrations 12 to 53 times higher than the elemental carbon levels. PMID:10561882

  10. A comparison of sampling and analytical methods for assessing occupational exposure to diesel exhaust in a railroad work environment

    SciTech Connect

    Verma, D.K.; Shaw, L.; Julian, J.; Smolynec, K.; Wood, C.; Shaw, D.

    1999-10-01

    Methods of assessing occupational exposure to diesel exhaust were evaluated in a railroad work environment. The American Conference of Governmental Industrial Hygienists (ACGIH{reg_sign})-recommended elemental carbon and respirable combustible dust methods of sampling and analysis for assessing diesel exhaust were included in the study. A total of 215 personal and area samples were collected using both size-selective and non-size-selective samplers. The results demonstrate that the elemental carbon method is suitable for the railroad environment and the respirable combustible dust method is not. All elemental carbon concentrations measured were below the proposed ACG1H Threshold Limit Value (TLV{reg_sign}) of 0.15 mg/m{sup 3}. The concentrations of oxides of nitrogen (nitric oxide and nitrogen dioxide) were also found to be below their respective TLVs. There is no correlation between elemental carbon or respirable combustible dust and the oxides of nitrogen. The elemental carbon as fraction of total carbon is about 13%, except for onboard locomotives where it is about 24%. Comparison of elemental carbon and respirable combustible dust measurements showed consistent relationships for most sampling locations with respirable combustible dust concentrations 12 to 53 times higher than the elemental carbon levels.

  11. Some Effects of Exposure to Exhaust-gas Streams on Emittance and Thermoelectric Power of Bare-wire Platinum Rhodium - Platinum Thermocouples

    NASA Technical Reports Server (NTRS)

    Glawe, George E; Shepard, Charles E

    1954-01-01

    Thermocouples were exposed to exhaust gases from the combustion of propane, 72-octane gasoline, and JP-4 fuel. Exposure increased the emissivity of the thermocouple wire, which increased its radiation error. Two methods are presented for determining the emittance of the wires. The emissivity of a clean platinum rhodium-platinum thermocouple was approximately 0.2 in the temperature range investigated, while the emittance of an exposed thermocouple coated with exhaust residue was about 0.5. The exposure caused negligible change in the thermoelectric power of the thermocouples.

  12. Diesel exhaust particles induce oxidative stress, proinflammatory signaling, and P-glycoprotein up-regulation at the blood-brain barrier

    PubMed Central

    Hartz, Anika M. S.; Bauer, Björn; Block, Michelle L.; Hong, Jau-Shyong; Miller, David S.

    2008-01-01

    Here, we report that diesel exhaust particles (DEPs), a major constituent of urban air pollution, affect blood-brain barrier function at the tissue, cellular, and molecular levels. Isolated rat brain capillaries exposed to DEPs showed increased expression and transport activity of the key drug efflux transporter, P-glycoprotein (6 h EC50 was ∼5 μg/ml). Up-regulation of P-glycoprotein was abolished by blocking transcription or protein synthesis. Inhibition of NADPH oxidase or pretreatment of capillaries with radical scavengers ameliorated DEP-induced P-glycoprotein up-regulation, indicating a role for reactive oxygen species in signaling. DEP exposure also increased brain capillary tumor necrosis factor-α (TNF-α) levels. DEP-induced P-glycoprotein up-regulation was abolished when TNF-receptor 1 (TNF-R1) was blocked and was not evident in experiments with capillaries from TNF-R1 knockout mice. Inhibition of JNK, but not NF-κB, blocked DEP-induced P-glycoprotein up-regulation, indicating a role for AP-1 in the signaling pathway. Consistent with this, DEPs increased phosphorylation of c-jun. Together, our results show for the first time that a component of air pollution, DEPs, alters blood-brain barrier function through oxidative stress and proinflammatory cytokine production. These experiments disclose a novel blood-brain barrier signaling pathway, with clear implications for environmental toxicology, CNS pathology, and the pharmacotherapy of CNS disorders.—Hartz, A. M. S., Bauer, B., Block, M. L., Hong, J.-S., Miller, D.-S. Diesel exhaust particles induce oxidative stress, proinflammatory signaling, and P-glycoprotein up-regulation at the blood-brain barrier. PMID:18474546

  13. Contribution of indoor-generated particles to residential exposure

    NASA Astrophysics Data System (ADS)

    Isaxon, C.; Gudmundsson, A.; Nordin, E. Z.; Lönnblad, L.; Dahl, A.; Wieslander, G.; Bohgard, M.; Wierzbicka, A.

    2015-04-01

    The majority of airborne particles in residences, when expressed as number concentrations, are generated by the residents themselves, through combustion/thermal related activities. These particles have a considerably smaller diameter than 2.5 μm and, due to the combination of their small size, chemical composition (e.g. soot) and intermittently very high concentrations, should be regarded as having potential to cause adverse health effects. In this study, time resolved airborne particle measurements were conducted for seven consecutive days in 22 randomly selected homes in the urban area of Lund in southern Sweden. The main purpose of the study was to analyze the influence of human activities on the concentration of particles in indoor air. Focus was on number concentrations of particles with diameters <300 nm generated by indoor activities, and how these contribute to the integrated daily residential exposure. Correlations between these particles and soot mass concentration in total dust were also investigated. It was found that candle burning and activities related to cooking (using a frying pan, oven, toaster, and their combinations) were the major particle sources. The frequency of occurrence of a given concentration indoors and outdoors was compared for ultrafine particles. Indoor data was sorted into non-occupancy and occupancy time, and the occupancy time was further divided into non-activity and activity influenced time. It was found that high levels (above 104 cm-3) indoors mainly occur during active periods of occupancy, while the concentration during non-activity influenced time differs very little from non-occupancy time. Total integrated daily residential exposure of ultrafine particles was calculated for 22 homes, the contribution from known activities was 66%, from unknown activities 20%, and from background/non-activity 14%. The collected data also allowed for estimates of particle source strengths for specific activities, and for some activities

  14. EXACERBATION OF ATHEROSCLEROSIS FOLLOWING EXPOSURE TO VARIOUS COMBUSTION SOURCE PARTICLES

    EPA Science Inventory

    Exposure of ApoE knockout (ApoE-/-) mice to concentrated ambient particles (CAPs) has been shown to increase arterial plaque area and size. CAPs are a complex aerosol mixture consisting of wind-blown dust, emissions from the combustion of fossil fuels, and secondary tr...

  15. CARDIOVASCULAR RESPONSES TO ULTRAFINE CARBON PARTICLE EXPOSURES IN RATS

    EPA Science Inventory

    TD-02-042 (U. KODAVANTI) GPRA # 10108

    Cardiovascular Responses to Ultrafine Carbon Particle Exposures in Rats.
    V. Harder1, B. Lentner1, A. Ziesenis1, E. Karg1, L. Ruprecht1, U. Kodavanti2, A. Stampfl3, J. Heyder1, H. Schulz1
    GSF- Institute for Inhalation Biology1, I...

  16. Mutagenicity of diesel engine exhaust is eliminated in the gas phase by an oxidation catalyst but only slightly reduced in the particle phase.

    PubMed

    Westphal, Götz A; Krahl, Jürgen; Munack, Axel; Ruschel, Yvonne; Schröder, Olaf; Hallier, Ernst; Brüning, Thomas; Bünger, Jürgen

    2012-06-01

    Concerns about adverse health effects of diesel engine emissions prompted strong efforts to minimize this hazard, including exhaust treatment by diesel oxidation catalysts (DOC). The effectiveness of such measures is usually assessed by the analysis of the legally regulated exhaust components. In recent years additional analytical and toxicological tests were included in the test panel with the aim to fill possible analytical gaps, for example, mutagenic potency of polycyclic aromatic hydrocarbons (PAH) and their nitrated derivatives (nPAH). This investigation focuses on the effect of a DOC on health hazards from combustion of four different fuels: rapeseed methyl ester (RME), common mineral diesel fuel (DF), SHELL V-Power Diesel (V-Power), and ARAL Ultimate Diesel containing 5% RME (B5ULT). We applied the European Stationary Cycle (ESC) to a 6.4 L turbo-charged heavy load engine fulfilling the EURO III standard. The engine was operated with and without DOC. Besides regulated emissions we measured particle size and number distributions, determined the soluble and solid fractions of the particles and characterized the bacterial mutagenicity in the gas phase and the particles of the exhaust. The effectiveness of the DOC differed strongly in regard to the different exhaust constituents: Total hydrocarbons were reduced up to 90% and carbon monoxide up to 98%, whereas nitrogen oxides (NO(X)) remained almost unaffected. Total particle mass (TPM) was reduced by 50% with DOC in common petrol diesel fuel and by 30% in the other fuels. This effect was mainly due to a reduction of the soluble organic particle fraction. The DOC caused an increase of the water-soluble fraction in the exhaust of RME, V-Power, and B5ULT, as well as a pronounced increase of nitrate in all exhausts. A high proportion of ultrafine particles (10-30 nm) in RME exhaust could be ascribed to vaporizable particles. Mutagenicity of the exhaust was low compared to previous investigations. The DOC reduced

  17. Exposure to Diesel Exhaust Up-regulates iNOS Expression in ApoE Knockout Mice

    PubMed Central

    Bai, Ni; Kido, Takashi; Kavanagh, Terrance J.; Kaufman, Joel D.; Rosenfeld, Michael E.; van Breemen, Cornelis; van Eeden, Stephan F.

    2012-01-01

    Traffic related particulate matter air pollution is a risk factor for cardiovascular events; however, the biological mechanisms are unclear. We hypothesize that diesel exhaust (DE) inhalation induces up-regulation of inducible nitric oxide synthase (iNOS), which is known to contribute to vascular dysfunction, progression of atherosclerosis and ultimately cardiovascular morbidity and mortality. Methods ApoE knockout mice (30-week) were exposed to DE (at 200µg/m3 of particulate matter) or filtered-air (control) for 7 weeks (6h/day, 5days/week). iNOS expression in the blood vessels and heart was evaluated by immunohistochemistry and western blotting analysis. To examine iNOS activity, thoracic aortae were mounted in a wire myograph, and vasoconstriction stimulated by phenylephrine (PE) was measured with and without the presence of the specific inhibitor for iNOS (1400W). NF-κB (p65) activity was examined by ELISA. The mRNA expression of iNOS and NF-κB (p65) was determined by real-time PCR. Results DE exposure significantly enhanced iNOS expression in the thoracic aorta (4-fold) and heart (1.5 fold). DE exposure significantly attenuated PE-stimulated vasoconstriction by ~20%, which was partly reversed by 1400W. The mRNA expression of iNOS and NF-κB was significantly augmented after DE exposure. NF-κB activity was enhanced 2-fold after DE inhalation, and the augmented NF-κB activity was positively correlated with iNOS expression (R2= 0.5998). Conclusions We show that exposure to DE increases iNOS expression and activity possibly via NF-κB-mediated pathway. We suspect that DE exposure-caused up-regulation of iNOS contributes to vascular dysfunction and atherogenesis, which could ultimately lead to urban air pollution-associated cardiovascular morbidity and mortality. PMID:21722660

  18. Personal exposure to JP-8 jet fuel vapors and exhaust at air force bases.

    PubMed Central

    Pleil, J D; Smith, L B; Zelnick, S D

    2000-01-01

    JP-8 jet fuel (similar to commercial/international jet A-1 fuel) is the standard military fuel for all types of vehicles, including the U.S. Air Force aircraft inventory. As such, JP-8 presents the most common chemical exposure in the Air Force, particularly for flight and ground crew personnel during preflight operations and for maintenance personnel performing routine tasks. Personal exposure at an Air Force base occurs through occupational exposure for personnel involved with fuel and aircraft handling and/or through incidental exposure, primarily through inhalation of ambient fuel vapors. Because JP-8 is less volatile than its predecessor fuel (JP-4), contact with liquid fuel on skin and clothing may result in prolonged exposure. The slowly evaporating JP-8 fuel tends to linger on exposed personnel during their interaction with their previously unexposed colleagues. To begin to assess the relative exposures, we made ambient air measurements and used recently developed methods for collecting exhaled breath in special containers. We then analyzed for certain volatile marker compounds for JP-8, as well as for some aromatic hydrocarbons (especially benzene) that are related to long-term health risks. Ambient samples were collected by using compact, battery-operated, personal whole-air samplers that have recently been developed as commercial products; breath samples were collected using our single-breath canister method that uses 1-L canisters fitted with valves and small disposable breathing tubes. We collected breath samples from various groups of Air Force personnel and found a demonstrable JP-8 exposure for all subjects, ranging from slight elevations as compared to a control cohort to > 100 [mutilpe] the control values. This work suggests that further studies should be performed on specific issues to obtain pertinent exposure data. The data can be applied to assessments of health outcomes and to recommendations for changes in the use of personal protective

  19. Transient exposure to proteins SOX2, Oct-4, and NANOG immortalizes exhausted tumor-infiltrating CTLs.

    PubMed

    Bhadurihauck, Anjuli; Li, Lei; Li, Qianqian; Wang, Jianjun; Xiao, Zhengguo

    2016-05-13

    Adoptive cell transfer therapy (ACT) is one of the most promising immunotherapies against cancer, using tumor-infiltrating lymphocytes (TILs) expanded in vitro. Tumor-infiltrating cytotoxic T lymphocytes (TICTLs) play a prominent role in cancer control. TILs terminally differentiate in response to immunosuppressive environments within tumors, and thus are slow to expand and challenging to maintain both in vitro and in patients. To reverse this exhaustion, we utilize a nuclear protein delivery system that exposes TICTLs to the SOX2, Oct-4, and NANOG (SON) proteins. Unlike activated naïve CTLs (effector CTLs), TICTLs respond favorably to SON treatment, exhibiting steady proliferation and extended survivability independent of cytokine and antigen stimulation. Though TICTLs treated with SON (STICTLs) still express T cell receptors as well as other critical downstream components, they are unresponsive to antigen challenge, suggesting that SON treatment regresses TICTLs into a state similar to that of an early double negative T cell. Our findings indicate the TICTL response to SON proteins is unique when compared to effector CTLs, suggesting TICTLs may be sensitive to regulation by other lineage-specific transcription factors and opening a promising new avenue into cancer immunotherapy. To our knowledge, this is the first report on lineage reprogramming of TILs using protein stem cell transcription factors delivered directly to the nucleus. PMID:27084449

  20. The Effect of In Utero Diesel Exhaust (DE) Exposure on Development of Allergic Inflammation in Offspring

    EPA Science Inventory

    Recent studies have shown that pre-term birth weights and the incidence of asthma are increased in children born from mothers who live close to heavily trafficked roads and highways. In this study we examined the effect of inhalation DE exposure by pregnant mice on the subsequen...

  1. Effects of combinations of diesel exhaust and ozone exposure on lung function in human volunteers.

    EPA Science Inventory

    Ozone (03) exposure induces changes in human lung function, typically seen as a decrease in forced expiratory volume in one sec (FEV1) and forced vital capacity (FVC). Because people are usually exposed to other ambient air pollutants simultaneously with 03, there may be interact...

  2. PERSONAL EXPOSURE TO JP-8 JET FUEL VAPORS AND EXHAUST AT AIR FORCE BASES

    EPA Science Inventory

    JP-8 jet fuel (similar to commercial/international jet A-1 fuel) is the standard military fuel for all types of vehicles, including the U.S. Air Force aircraft inventory. As such, JP-8 presents the most common chemical exposure in the Air Force, particularly for flight and gro...

  3. At high cardiac output, diesel exhaust exposure increases pulmonary vascular resistance and decreases distensibility of pulmonary resistive vessels.

    PubMed

    Wauters, Aurélien; Vicenzi, Marco; De Becker, Benjamin; Riga, Jean-Philippe; Esmaeilzadeh, Fatemeh; Faoro, Vitalie; Vachiéry, Jean-Luc; van de Borne, Philippe; Argacha, Jean-François

    2015-12-15

    Air pollution has recently been associated with the development of acute decompensated heart failure, but the underlying biological mechanisms remain unclear. A pulmonary vasoconstrictor effect of air pollution, combined with its systemic effects, may precipitate decompensated heart failure. The aim of the present study was to investigate the effects of acute exposure to diesel exhaust (DE) on pulmonary vascular resistance (PVR) under resting and stress conditions but also to determine whether air pollution may potentiate acquired pulmonary hypertension. Eighteen healthy male volunteers were exposed to ambient air (AA) or dilute DE with a particulate matter of <2.5 μm concentration of 300 μg/m(3) for 2 h in a randomized, crossover study design. The effects of DE on PVR, on the coefficient of distensibilty of pulmonary vessels (α), and on right and left ventricular function were evaluated at rest (n = 18), during dobutamine stress echocardiography (n = 10), and during exercise stress echocardiography performed in hypoxia (n = 8). Serum endothelin-1 and fractional exhaled nitric oxide were also measured. At rest, exposure to DE did not affect PVR. During dobutamine stress, the slope of the mean pulmonary artery pressure-cardiac output relationship increased from 2.8 ± 0.5 mmHg · min · l (-1) in AA to 3.9 ± 0.5 mmHg · min · l (-1) in DE (P < 0.05) and the α coefficient decreased from 0.96 ± 0.15 to 0.64 ± 0.12%/mmHg (P < 0.01). DE did not further enhance the hypoxia-related upper shift of the mean pulmonary artery pressure-cardiac output relationship. Exposure to DE did not affect serum endothelin-1 concentration or fractional exhaled nitric oxide. In conclusion, acute exposure to DE increased pulmonary vasomotor tone by decreasing the distensibility of pulmonary resistive vessels at high cardiac output. PMID:26497960

  4. Strategies for setting occupational exposure limits for particles.

    PubMed Central

    Greim, H A; Ziegler-Skylakakis, K

    1997-01-01

    To set occupational exposure limits (OELs) for aerosol particles, dusts, or chemicals, one has to evaluate whether mechanistic considerations permit identification of a no observed effect level (NOEL). In the case of carcinogenic effects, this can be assumed if no genotoxicity is involved, and exposure is considered safe if it does not exceed the NOEL. If tumor induction is associated with genotoxicity, any exposure is considered to be of risk, although a NOEL may be identified in the animal or human exposure studies. This must also be assumed when no information on the carcinogenic mechanism, including genotoxicity, is available. Aerosol particles, especially fibrous dusts, which include man-made mineral fiber(s) (MMMF), present a challenge for toxicological evaluation. Many MMMF that have been investigated have induced tumors in animals and genotoxicity in vitro. Since these effects have been associated with long-thin fiber geometry and high durability in vivo, all fibers meeting such criteria are considered carcinogenic unless the opposite has been demonstrated. This approach is practicable. Investigations on fiber tumorigenicity/genotoxicity should include information on dose response, pathobiochemistry, particle clearance, and persistence of the material in the target organ. Such information will introduce quantitative aspects into the qualitative approach that has so far been used to classify fibrous dusts as carcinogens. The rationales for classifying the potential carcinogenicity of MMMF and for setting OELs used by the different European committees and regulatory agencies are described. PMID:9400750

  5. DIESEL PARTICLE GENERATION, CHARACTERIZATION, AND DIRECT ANIMAL EXPOSURE STUDIES

    EPA Science Inventory

    Inhalation of diesel exhaust is associated with the development of asthma as well as other adverse health effects. Studies have also demonstrated that diesel exhaust induces pulmonary changes that worsen asthmatic responses to respiratory allergens. This paper describes the des...

  6. Hamilton study: estimating exposure to ambient suspended particles

    SciTech Connect

    Pengelly, L.D.; Goldsmith, C.H.; Kerigan, A.T.; Furlong, W.; Toplack, S.

    1987-12-01

    In the industrial city of Hamilton, Ontario, Canada, we recently carried out an epidemiological study of the effect of environmental factors on respiratory health in 3500 elementary school children. The level and size distribution of suspended particles in ambient air was measured from 24-h samples taken at 6-day intervals from a network of 29 hivol TSP samplers, and nine Andersen 2000 4-stage cascade impactors. Exposure was computed by generating a 3-dimensional response surface using a linear regression model of the form: TSP = (1 + E + N)/sup 2/, based on monthly geometrical mean data for all sites. From this response surface generated for a given month, TSP levels were predicted by the model for all schools by specifying their geographical coordinates. The yearly exposure for a given child was determined from the arithmetic mean of the predicted values for 12 monthly TSP levels. A similar procedure was employed for calculation of the exposure to the fine (less than or equal to 3.3 ..mu..m) and coarse (> 3.3 ..mu..m) size fraction, as well as the aerodynamic mass median diameter of particles from the network of cascade impactors. Results of the measurements showed that gradients for TSP up to approximately 10 ..mu..g/m/sup 3//km exist over the city covering distances from 5 to 10 km. The range of 1 yr mean exposure values calculated for each child was from 30.5 ..mu..g/m/sup 3/ to 74.5 ..mu../m/sup 3/. Comparable figures for particle size were up to 0.3 ..mu..m AMMD (aerodynamic mass median diameter)/km and annual mean particle size exposure from 2.69 to 3.53 ..mu..m AMMD.

  7. Biodiesel exhaust-induced cytotoxicity and proinflammatory mediator production in human airway epithelial cells.

    PubMed

    Mullins, Benjamin J; Kicic, Anthony; Ling, Kak-Ming; Mead-Hunter, Ryan; Larcombe, Alexander N

    2016-01-01

    Increasing use of biodiesel has prompted research into the potential health effects of biodiesel exhaust exposure. Few studies directly compare the health consequences of mineral diesel, biodiesel, or blend exhaust exposures. Here, we exposed human epithelial cell cultures to diluted exhaust generated by the combustion of Australian ultralow-sulfur-diesel (ULSD), unprocessed canola oil, 100% canola biodiesel (B100), and a blend of 20% canola biodiesel mixed with 80% ULSD. The physicochemical characteristics of the exhaust were assessed and we compared cellular viability, apoptosis, and levels of interleukin (IL)-6, IL-8, and Regulated on Activation, Normal T cell Expressed and Secreted (RANTES) in exposed cultured cells. Different fuel types produced significantly different amounts of exhaust gases and different particle characteristics. All exposures resulted in significant apoptosis and loss of viability when compared with control, with an increasing proportion of biodiesel being correlated with a decrease in viability. In most cases, exposure to exhaust resulted in an increase in mediator production, with the greatest increases most often in response to B100. Exposure to pure canola oil (PCO) exhaust did not increase mediator production, but resulted in a significant decrease in IL-8 and RANTES in some cases. Our results show that canola biodiesel exhaust exposure elicits inflammation and reduces viability of human epithelial cell cultures in vitro when compared with ULSD exhaust exposure. This may be related to an increase in particle surface area and number in B100 exhaust when compared with ULSD exhaust. Exposure to PCO exhaust elicited the greatest loss of cellular viability, but virtually no inflammatory response, likely due to an overall increase in average particle size. PMID:25045158

  8. One versus five-days of exposure to varying concentrations of B100 soya biodiesel exhaust reveals a threshold concentration for increased sensitivity to aconitine-induced arrhythmia

    EPA Science Inventory

    Although biodiesel (BD) is rapidly being considered as an alternative to diesel fuel, its health effects have not been thoroughly characterized. We previously used the aconitine challenge test to demonstrate that a single exposure to petroleum diesel exhaust (DE) increases the ri...

  9. Increased levels of etheno-DNA adducts and genotoxicity biomarkers of long-term exposure to pure diesel engine exhaust.

    PubMed

    Shen, Meili; Bin, Ping; Li, Haibin; Zhang, Xiao; Sun, Xin; Duan, Huawei; Niu, Yong; Meng, Tao; Dai, Yufei; Gao, Weimin; Yu, Shanfa; Gu, Guizhen; Zheng, Yuxin

    2016-02-01

    Etheno-DNA adducts are biomarkers for assessing oxidative stress. In this study, the aim was to detect the level of etheno-DNA adducts and explore the relationship between the etheno-DNA adducts and genotoxicity biomarkers of the diesel engine exhaust (DEE)-exposed workers. We recruited 86 diesel engine testing workers with long-term exposure to DEE and 99 non-DEE-exposed workers. The urinary mono-hydroxylated polycyclic aromatic hydrocarbons (OH-PAHs) and etheno-DNA adducts (εdA and εdC) were detected by HPLC-MS/MS and UPLC-MS/MS, respectively. Genotoxicity biomarkers were also evaluated by comet assay and cytokinesis-block micronucleus assay. The results showed that urinary εdA was significantly higher in the DEE-exposed workers (p<0.001), exhibited 2.1-fold increase compared with the non-DEE-exposed workers. The levels of urinary OH-PAHs were positively correlated with the level of εdA among all the study subjects (p<0.001). Moreover, we found that the increasing level of εdA was significantly associated with the increased olive tail moment, percentage of tail DNA, or frequency of micronucleus in the study subjects (p<0.01). No significant association was observed between the εdC level and any measured genotoxicity biomarkers. In summary, εdA could serve as an indicator for DEE exposure in the human population. PMID:26588802

  10. Modelling of aircrew radiation exposure during solar particle events

    NASA Astrophysics Data System (ADS)

    Al Anid, Hani Khaled

    In 1990, the International Commission on Radiological Protection recognized the occupational exposure of aircrew to cosmic radiation. In Canada, a Commercial and Business Aviation Advisory Circular was issued by Transport Canada suggesting that action should be taken to manage such exposure. In anticipation of possible regulations on exposure of Canadian-based aircrew in the near future, an extensive study was carried out at the Royal Military College of Canada to measure the radiation exposure during commercial flights. The radiation exposure to aircrew is a result of a complex mixed-radiation field resulting from Galactic Cosmic Rays (GCRs) and Solar Energetic Particles (SEPs). Supernova explosions and active galactic nuclei are responsible for GCRs which consist of 90% protons, 9% alpha particles, and 1% heavy nuclei. While they have a fairly constant fluence rate, their interaction with the magnetic field of the Earth varies throughout the solar cycles, which has a period of approximately 11 years. SEPs are highly sporadic events that are associated with solar flares and coronal mass ejections. This type of exposure may be of concern to certain aircrew members, such as pregnant flight crew, for which the annual effective dose is limited to 1 mSv over the remainder of the pregnancy. The composition of SEPs is very similar to GCRs, in that they consist of mostly protons, some alpha particles and a few heavy nuclei, but with a softer energy spectrum. An additional factor when analysing SEPs is the effect of flare anisotropy. This refers to the way charged particles are transported through the Earth's magnetosphere in an anisotropic fashion. Solar flares that are fairly isotropic produce a uniform radiation exposure for areas that have similar geomagnetic shielding, while highly anisotropic events produce variable exposures at different locations on the Earth. Studies of neutron monitor count rates from detectors sharing similar geomagnetic shielding properties

  11. Predictive models for deposition of inhaled diesel exhaust particles in humans and laboratory species. Research report, July 1984-January 1987

    SciTech Connect

    Yu, C.P.; Xu, G.B.

    1987-07-01

    A deposition model for diesel-exhaust particles was formulated mathematically from available scientific data, and was used to predict the deposition of particles in the airways of laboratory animals and of humans of different ages. In addition, a lung-growth model was formulated for humans, from infancy to adulthood, to predict the effect of age on deposition. The investigators predicted from their models that: (1) deposition in the alveoli is markedly affected by changes in the size distribution of particles; (2) nose- versus mouth-breathing had little effect on deposition in the alveoli; (3) increased minute ventilation substantially increased the rate of particle deposition; and (4) age (in humans) influenced the levels of deposition observed in the unciliated regions of the airways (the highest levels of deposition occurred in infants under two years, decreased in children over two years, and decreased again in adults aged 25 years or older); and (5) the deposition rate in laboratory animals was higher than in humans of all ages.

  12. Organic extract of diesel exhaust particles stimulates expression of Ia and costimulatory molecules associated with antigen presentation in rat peripheral blood monocytes but not in alveolar macrophages

    SciTech Connect

    Koike, Eiko . E-mail: ekoike@nies.go.jp; Kobayashi, Takahiro

    2005-12-15

    We hypothesized that diesel exhaust particles (DEP) induce the activation of antigen-presenting cells (APC) in lung. The present study was designed to clarify the following about DEP: (1) whether it affects the expression of Ia and B7 molecules in alveolar macrophages (AM) as a mature cell or in peripheral blood monocytes (PBM) as an immature cell (2) if it affects the antigen-presenting (AP) activity of PBM (3) what component of DEP is responsible for the effects, and (4) whether the effect of DEP is related to oxidative stress. DEP was extracted with methylene chloride. Cells were exposed to whole DEP, organic extract, or residual particles for 24 h. Cell-surface molecules were measured by flow cytometry. AP activity was assessed by antigen-specific T cell proliferation. Whole DEP or organic extract significantly increased the expression of Ia and B7 molecules on PBM but not on AM. No significant effect of residual particles was observed. A low concentration of organic extract also increased the AP activity of PBM. When the induction of an antioxidative enzyme was assessed, heme oxygenase-1 protein was found to be significantly increased by exposure to whole DEP, and the organic extract was more effective than the residual particles. Furthermore, the organic extract-induced expression of Ia antigen on PBM was reduced by the addition of an antioxidative agent. These results suggest that DEP may act on immature APC and enhance their AP activity and that the action contributing to oxidative stress may be mediated by organic compounds of DEP.

  13. Evaluation of the particle measurement programme (PMP) protocol to remove the vehicles' exhaust aerosol volatile phase.

    PubMed

    Giechaskiel, B; Chirico, R; Decarlo, P F; Clairotte, M; Adam, T; Martini, G; Heringa, M F; Richter, R; Prevot, A S H; Baltensperger, U; Astorga, C

    2010-10-01

    European regulation for Euro 5/6 light duty emissions introduced the measurement of non-volatile particles with diameter >23 nm. The volatile phase is removed by using a heated dilution stage (150 degrees C) and a heated tube (at 300-400 degrees C). We investigated experimentally the removal efficiency for volatile species of the specific protocol by conducting measurements with two Euro 3 diesel light duty vehicles, a Euro 2 moped, and a Euro III heavy duty vehicle with the system's heaters on and off. The particle number distributions were measured with a Scanning Mobility Particle Sizer (SMPS) and a Fast Mobility Particle Sizer (FMPS). An Aerosol Mass Spectrometer (AMS) was used to identify the non-refractory chemical composition of the particles. A Multi-Angle Absorption Photometer (MAAP) was used to measure the black carbon concentration. The results showed that the condensed material in the accumulation mode (defined here as particles in the diameter range of approximately 50-500 nm) was removed with an efficiency of 50-90%. The (volatile) nucleation mode was also completely evaporated or was decreased to sizes <23 nm; thus these particles wouldn't be counted from the particle counter, indicating the robustness of the protocol. PMID:20692024

  14. The effects of an open and closed divertor on particle exhaust during edge-localized mode suppression by resonant magnetic perturbations in DIII-D

    SciTech Connect

    Unterberg, E. A.; Schmitz, O.; Evans, T.E.; Maingi, Rajesh; Brooks, N. H.; Fenstermacher, M. E.; Mordijck, S.; Moyer, R.A.; Orlov, D. M.

    2010-01-01

    This paper compares the effects of divertor geometry on particle exhaust characteristics during the suppression of ELM using resonant magnetic perturbations (RMPs) on DIII-D. The subject is timely, particularly for ITER, because the combination of techniques to control or mitigate ELMs and control particle exhaust can provide confidence in the ability of an external pumping system to fully remove the particle exhaust. The differences between an open and closed divertor magnetic topology show a strong coupling of the perturbed strikepoint to the pumping manifold in closed divertor configurations, which can increase the particle exhaust by a factor of four. There is also an observed dependence on q(95) in this configuration, which is a common feature of RMP ELM suppression. Neutral density in both the active and non-active divertors is seen to increase during the RMP in the ISS configuration, and edge plasma conditions (i.e. n(e,sep) and midplane profile of D(alpha)) are seen to increase in the closed divertor configuration. Finally, the pumping exhaust is also shown to have a strong dependence on local measurements of the recycling flux. These observations, when taken as a whole, point to a substantial change in the plasma edge conditions, i.e. near the LCFS, throughout the poloidal cross-section of the vacuum vessel. This is coincident with the application of the RMP affecting the pumping capability of the system.

  15. DIESEL EXHAUST PARTICLES ENHANCE INFLUENZA VIRUS INFECTIVITY BY INCREASING VIRUS ATTACHMENT

    EPA Science Inventory

    Despite vaccination and antiviral therapies, influenza infections continue to cause large scale morbidity and mortality every year. Several factors, such as age and nutritional status can affect the incidence and severity of influenza infections. Moreover, exposure to air polluta...

  16. Diesel exhaust exposure enhances venoconstriction via uncoupling of eNOS

    SciTech Connect

    Knuckles, Travis L.; Lund, Amie K.; Lucas, Selita N.; Campen, Matthew J.

    2008-08-01

    Environmental air pollution is associated with adverse cardiovascular events, including increased hospital admissions due to heart failure and myocardial infarction. The exact mechanism(s) by which air pollution affects the heart and vasculature is currently unknown. Recent studies have found that exposure to air pollution enhances arterial vasoconstriction in humans and animal models. Work in our laboratory has shown that diesel emissions (DE) enhance vasoconstriction of mouse coronary arteries. Thus, we hypothesized that DE could enhance vasoconstriction in arteries and veins through uncoupling of endothelial nitric oxide synthase (eNOS). To test this hypothesis, we first bubbled DE through a physiological saline solution and exposed isolated mesenteric veins. Second, we exposed animals, whole body, to DE at 350 {mu}g/m{sup 3} for 4 h, after which mesenteric arteries and veins were isolated. Results from these experiments show that saline bubbled with DE as well as inhaled DE enhances vasoconstriction in veins but not arteries. Exposure to several representative volatile organic compounds found in the DE-exposed saline did not enhance arterial constriction. L-nitro-arginine-methyl-ester (L-NAME), an eNOS inhibitor, normalized the control vessels to the DE-exposed vessels implicating an uncoupling of eNOS as a mechanism for enhanced vasoconstriction. The principal conclusions of this research are 1) veins exhibit endothelial dysfunction following in vivo and ex vivo exposures to DE, 2) veins appear to be more sensitive to DE effects than arteries, and 3) DE components most likely induce endothelial dysfunction through the uncoupling of eNOS.

  17. Monitoring of heavy metal particle emission in the exhaust duct of a foundry using LIBS.

    PubMed

    Dutouquet, C; Gallou, G; Le Bihan, O; Sirven, J B; Dermigny, A; Torralba, B; Frejafon, E

    2014-09-01

    Heavy metals have long been known to be detrimental to human health and the environment. Their emission is mainly considered to occur via the atmospheric route. Most of airborne heavy metals are of anthropogenic origin and produced through combustion processes at industrial sites such as incinerators and foundries. Current regulations impose threshold limits on heavy metal emissions. The reference method currently implemented for quantitative measurements at exhaust stacks consists of on-site sampling of heavy metals on filters for the particulate phase (the most prominent and only fraction considered in this study) prior to subsequent laboratory analysis. Results are therefore known only a few days after sampling. Stiffer regulations require the development of adapted tools allowing automatic, on-site or even in-situ measurements with temporal resolutions. The Laser-Induced Breakdown Spectroscopy (LIBS) technique was deemed as a potential candidate to meet these requirements. On site experiments were run by melting copper bars and monitoring emission of this element in an exhaust duct at a pilot-scale furnace in a French research center dedicated to metal casting. Two approaches designated as indirect and direct analysis were broached in these experiments. The former corresponds to filter enrichment prior to subsequent LIBS interrogation whereas the latter entails laser focusing right through the aerosol for detection. On-site calibration curves were built and compared with those obtained at laboratory scale in order to investigate possible matrix and analyte effects. Eventually, the obtained results in terms of detection limits and quantitative temporal monitoring of copper emission clearly emphasize the potentialities of the direct LIBS measurements. PMID:24913859

  18. Development of indigenous local exhaust ventilation system: reduction of welders exposure to welding fumes.

    PubMed

    Zaidi, Shakeel; Sathawara, Natvarbhai; Kumar, Sunil; Gandhi, Sumitra; Parmar, Chimanlal; Saiyed, Habibullah

    2004-07-01

    Two (portable and mobile) local exhaust ventilation (LEV) units were developed in collaboration with the Rural Technology Institute, Gandhinagar, India. Basically, each unit consists of three parts comprising an electric motor, a blower and a fume hood. In both units the motor is fixed in a rectangular iron frame in a foot-mount position and equipped compactly with a blower, which in turn is connected to a fume hood through a flexible hosepipe. The portable unit is light in weight (50 kg) and has a cone shaped metallic fume hood. The mobile unit, on the other hand, differs from the portable model with respect to its weight (150 kg), size, RPM, voltage requirement, hood shape and size, and has a motor enclosure. The efficiency of the portable and mobile units on trial bases was tested by measuring the manganese concentration as a reference metal in welding fumes generated by electric arc welding. The concentration of manganese (mean +/- SD) was 0.218 +/- 0.06 microg/m3 in the general environment. In the workplace area where joining of metal objects by welding was done, the concentration of manganese was found to be 0.63 +/- 0.09 and 3.75 +/- 0.56 microg/m3 at a distance of 5 m and 2 m away from the site of operation, respectively. In the breathing zone it was 22.16 +/- 20.90 microg/m3 which was reduced to 8.25 +/- 4.5 microg /m3 after application of a portable LEV showing about 63% removal of the manganese concentration from the breathing zone of the welder. In another experiment conducted with a mobile LEV unit for heavy-duty work, the concentration of manganese in the breathing zone without operating the mobile LEV was 70.06 +/- 37.38 microg /m3 but was lowered to 8.29 +/- 1.76 microg /m3 after operating the mobile LEV. This indicated an average removal of manganese content by about 88% from the breathing zone of the welder. In both the experiments locations of sample collection were similar. PMID:15308834

  19. Sequential and simultaneous thermal and particle exposure of tungsten

    NASA Astrophysics Data System (ADS)

    Steudel, I.; Huber, A.; Kreter, A.; Linke, J.; Sergienko, G.; Unterberg, B.; Wirtz, M.

    2016-02-01

    The broad array of expected loading conditions in a fusion reactor such as ITER necessitates high requirements on the plasma facing materials (PFMs). Tungsten, the PFM for the divertor region, the most affected part of the in-vessel components, must thus sustain severe, distinct exposure conditions. Accordingly, comprehensive experiments investigating sequential and simultaneous thermal and particle loads were performed on double forged pure tungsten, not only to investigate whether the thermal and particle loads cause damage but also if the sequence of exposure maintains an influence. The exposed specimens showed various kinds of damage such as roughening, blistering, and cracking at a base temperature where tungsten could be ductile enough to compensate the induced stresses exclusively by plastic deformation (Pintsuk et al 2011 J. Nucl. Mater. 417 481-6). It was found out that hydrogen has an adverse effect on the material performance and the loading sequence on the surface modification.

  20. Inhalation of diesel exhaust induces acute arterial vasocontruction in healthy volunteers

    EPA Science Inventory

    Epidemiological studies have shown an association between the incidence of adverse cardiovascular effects and exposure to ambient particulate matter (PM). Diesel exhaust particles (DE) are a major contributor to PM in urban areas. Advanced age and certain polymorphisms are among...

  1. Acute skin lesions due to localized ``hot particle`` radiation exposures

    SciTech Connect

    Baum, J.W.; Carsten, A.L.; Kaurin, D.G.L.; Schaefer, C.W.

    1996-06-01

    Purpose of the studies was to determine incidence and severity of lesions resulting from localized deposition of dose to the skin from small (<0.5 mm) discrete radioactive particles. Hanford mini-swine were exposed to localized doses from 0.2 to over 600 Gy (averaged over 1 cm{sup 2} at 70{mu}m depth) from isotopes having max beta particle energies from about 0.3-3 MeV. Incidence of erythema and scabs (indicating ulceration) were scored routinely for up to 71 days post-irradiation. Responses followed normal probability distributions, and thus, no true threshold could be defined. Ten and 50% incidence rates were deduced using probit analyses. Lowest dose producing 10% incidence was about 1 Gy for exposures to Yb-175 (0.5 MeV max energy) beta particles. Severity of lesions was estimated using diameters and persistence. From preliminary considerations of probability of induction, size, and persistence of acute lesions, a special limit for hot particle exposures in the range of 5-50 Gy may be reasonable, with an action level between about 1 Gy and the limit.

  2. Modelling the fate of ultrafine particles from exhaust pipe to rural background: an analysis of time scales for dilution, coagulation and deposition

    NASA Astrophysics Data System (ADS)

    Ketzel, Matthias; Berkowicz, Ruwim

    We investigate the time scales of various dynamic processes during the evolution of the particle size distribution from its emission from a vehicle exhaust pipe through its dilution at kerbside and urban level. In addition, the situation in a road tunnel or near a highway is discussed. The derived formula framework allows the estimation of approximated time scales based on a given particle size distribution for the processes dilution with background air, coagulation, deposition and condensation. The variation of the time scales for these processes with "lifetime" of the exhaust particles and the dependence of the time scales on the particle size is shown. We identify the spatial or temporal scales under which the discussed processes are important and have to be included in operational particle pollution models.

  3. Exhaust particle characterization for lean and stoichiometric DI vehicles operating on ethanol-gasoline blends

    SciTech Connect

    Storey, John Morse; Barone, Teresa L; Thomas, John F; Huff, Shean P

    2012-01-01

    Gasoline direct injection (GDI) engines can offer better fuel economy and higher performance over their port fuel-injected (PFI) counterparts, and are now appearing in increasingly more U.S. and European vehicles. Small displacement, turbocharged GDI engines are replacing large displacement engines, particularly in light-duty trucks and sport utility vehicles, in order for manufacturers to meet the U.S. fuel economy standards for 2016. Furthermore, lean-burn GDI engines can offer even higher fuel economy than stoichiometric GDI engines and have overcome challenges associated with cost-effective aftertreatment for NOx control. Along with changes in gasoline engine technology, fuel composition may increase in ethanol content beyond the current 10% due to the recent EPA waiver allowing 15% ethanol. In addition, the Renewable Fuels Standard passed as part of the 2007 Energy Independence and Security Act (EISA) mandates the use of biofuels in upcoming years. GDI engines are of environmental concern due to their high particulate matter (PM) emissions relative to port-fuel injected (PFI) gasoline vehicles; widespread market penetration of GDI vehicles may result in additional PM from mobile sources at a time when the diesel contribution is declining. In this study, we characterized particulate emissions from a European certified lean-burn GDI vehicle operating on ethanol-gasoline blends. Particle mass and particle number concentration emissions were measured for the Federal Test Procedure urban driving cycle (FTP 75) and the more aggressive US06 driving cycle. Particle number-size distributions and organic to elemental carbon ratios (OC/EC) were measured for 30 MPH and 80 MPH steady-state operation. In addition, particle number concentration was measured during wide open throttle accelerations (WOTs) and gradual accelerations representative of the FTP 75. Fuels included certification gasoline and 10% (E10) and 20% (E20) ethanol blends from the same supplier. The particle

  4. Characterization of Hairdresser Exposure to Airborne Particles during Hair Bleaching.

    PubMed

    Nilsson, Patrik T; Marini, Sara; Wierzbicka, Aneta; Kåredal, Monica; Blomgren, Eva; Nielsen, Jörn; Buonanno, Giorgio; Gudmundsson, Anders

    2016-01-01

    Respiratory symptoms among hairdressers are often ascribed to the use of bleaching powders that contain persulfate salts. Such salts can act as allergens and airway irritants but the mechanisms behind the negative health effects are not fully known. In order to understand why some hairdressers experience respiratory symptoms during, and after, sessions of hair bleaching, it is of importance to characterize how exposure occurs. In this work we used time and particle size resolved instrumentation with the aim to measure the concentration of particles that hairdressers are exposed to during sessions of hair bleaching. We also used filter samples to collect particles for quantitative determination of persulfate (S2O8(2-)) content and for analysis by light microscopy. Two different types of bleaching powders were used, one marked as dust-free and one without this marking (denoted regular). The time resolved instrumentation revealed that particles <10 µm were emitted, specifically when the regular powder was prepared and mixed with hydrogen peroxide. In contrast to other research our work also revealed that supercoarse particles (>10 µm) were emitted during application of the bleaching, when both the regular and the dust-free powders were used. The measured level of persulfate, sampled in the breathing zone of the hairdressers, was on average 26 µg m(-3) when the regular powder was used and 11 µg m(-3) when the dust-free powder was used. This indicates that use of dust-free powder does not eliminate exposure to persulfates, it only lowers the concentration. We show that the site of sampling, or position of the hairdresser with regards to the hair being bleached, is of high importance in the determination of persulfate levels and exposure. This work focuses on the physical and chemical characterization of the particles released to the air and the results are important for accurate exposure assessments. Accurate assessments may in turn lead to a better understanding of

  5. INHALATION OF OZONE AND DIESEL EXHAUST PARTICLES (DEP) INDUCES ACUTE AND REVERSIBLE CARDIAC GENE EXPRESSION CHANGES

    EPA Science Inventory

    We have recently shown that episodic but not acute exposure to ozone or DEP induces vascular effects that are associated with the loss of cardiac mitochondrial phospholipid fatty acids (DEP 2.0 mg/m3 > ozone, 0.4 ppm). In this study we determined ozone and DEP-induced cardiac gen...

  6. CHARACTERIZING THE SOURCES OF HUMAN EXPOSURE TO MUTAGENIC AND CARCINOGENIC CHEMICALS IN AIRBORNE FINE PARTICLES

    EPA Science Inventory

    Personal and ambient exposures to airborne fine particles, polycyclic aromatic hydrocarbons (PAH), and genotoxic activity has been studied in populations in the US, Japan, China, and the Czech Republic. Personal exposure monitors used to collect fine particles were extracted f...

  7. Real-time Characterization of Particle-bound Polycyclic Aromatic Hydrocarbons in Ambient Aerosols and From Motor-Vehicles Exhausts

    NASA Astrophysics Data System (ADS)

    Polidori, A.; Hu, S.; Biswas, S.; Sioutas, C.

    2007-12-01

    During the spring of 2007 a diffusion charger (DC), a photoelectric aerosol sensor (PAS), and a condensation particle counter (CPC) were operated a) in Wilmington (CA), an urban area near the Los Angeles port heavily influenced by a mix of industrial and gasoline- / diesel-fuelled vehicle emissions, and b) at the California Air Resource Board (CARB) Heavy-Duty Diesel Emissions Test Laboratory (HDETL), a dynamometer testing facility in downtown Los Angeles (CA). During the dynamometer tests, we characterized the exhausts of several individual types of vehicles, equipped with different emission control technologies, and operated under different driving conditions. Information about the chemical composition, active surface area, and particle number concentration from the PAS, DC, and CPC were combined to identify the main chemical and physical characteristics of the studied aerosols. In particular, the ratio between the PAS and the DC signals (PAS/DC) provided a reliable measurement of the amount of particle-bound Polycyclic Aromatic Hydrocarbon (pPAH) per unit area of the active surface of the particles. This quantity may be directly related to the amount of pPAHs transported into the human respiratory tract. Plots of the PAS/DC ratio versus the average surface particle diameter (Dp; estimated by combining DC and CPC measurements) were then used to distinguish between the presence/absence of nuclei mode particles and the presence/absence of an adsorbed layer on accumulation mode particles, for both ambient and dynamometer-tests data. All results were then complemented with measurements of the particle size distribution (SMPS) and of the black carbon (BC) aerosol content to obtain further insights on the pPAHs emitted by motor-vehicles and other sources. Integrated 24-h filter samples were also collected in Wilmington, solvent extracted and analyzed by GC/MS to determine the relative concentrations of the 11 most abundant pPAHs found at the urban site. Finally, these

  8. Mortality among members of a heavy construction equipment operators union with potential exposure to diesel exhaust emissions.

    PubMed Central

    Wong, O; Morgan, R W; Kheifets, L; Larson, S R; Whorton, M D

    1985-01-01

    A historical prospective mortality study was conducted on a cohort of 34 156 male members of a heavy construction equipment operators union with potential exposure to diesel exhaust emissions. This cohort comprised all individuals who were members of the International Union of Operating Engineers, Locals 3 and 3A, for at least one year between 1 January 1964 and 31 December 1978. The mortality experience of the entire cohort and several subcohorts was compared with that of United States white men, adjusted for age and calendar time. The comparison statistic was the commonly used standardised mortality ratio (SMR). Historical environmental measurements did not exist, but partial work histories were available for some cohort members through the union dispatch computer tapes. An attempt was made to relate mortality experience to the union members' dispatch histories. Overall mortality for the entire cohort and several subgroups was significantly lower than expected. When cause specific mortality was examined, however, the study provided suggestive evidence for the existence of several potential health problems in this cohort. Mortality from liver cancer for the entire cohort was significantly high. Although mortality from lung cancer for the entire cohort was similar to expected, a positive trend by latency was observed for lung cancer. A significant excess of mortality from lung cancer was found among the retirees and the group for whom no dispatch histories were available. Other dispatch groups showed no evidence of lung cancer excess. In addition, the total cohort experienced significant mortality excess from emphysema and accidental deaths. PMID:2410010

  9. Atmospheric scavenging of solid rocket exhaust effluents

    NASA Technical Reports Server (NTRS)

    Fenton, D. L.; Purcell, R. Y.

    1978-01-01

    Solid propellant rocket exhaust was directly utilized to ascertain raindrop scavenging rates for hydrogen chloride. Two chambers were used to conduct the experiments; a large, rigid walled, spherical chamber stored the exhaust constituents, while the smaller chamber housing all the experiments was charged as required with rocket exhaust HCl. Surface uptake experiments demonstrated an HCl concentration dependence for distilled water. Sea water and brackish water HCl uptake was below the detection limit of the chlorine-ion analysis technique used. Plant life HCl uptake experiments were limited to corn and soybeans. Plant age effectively correlated the HCl uptake data. Metallic corrosion was not significant for single 20 minute exposures to the exhaust HCl under varying relative humidity. Characterization of the aluminum oxide particles substantiated the similarity between the constituents of the small scale rocket and the full size vehicles.

  10. Individual dose and exposure of Italian children to ultrafine particles.

    PubMed

    Buonanno, G; Marini, S; Morawska, L; Fuoco, F C

    2012-11-01

    Time-activity patterns and the airborne pollutant concentrations encountered by children each day are an important determinant of individual exposure to airborne particles. This is demonstrated in this work by using hand-held devices to measure the real-time individual exposure of more than 100 children aged 8-11 years to particle number concentrations and average particle diameter, as well as alveolar and tracheobronchial deposited surface area concentration. A GPS-logger and activity diaries were also used to give explanation to the measurement results. Children were divided in three sample groups: two groups comprised of urban schools (school time from 8:30 am to 1:30 pm) with lunch and dinner at home, and the third group of a rural school with only dinner at home. The mean individual exposure to particle number concentration was found to differ between the three groups, ranging from 6.2 × 10(4)part.cm(-3) for children attending one urban school to 1.6 × 10(4)part.cm(-3) for the rural school. The corresponding daily alveolar deposited surface area dose varied from about 1.7 × 10(3)mm(2) for urban schools to 6.0 × 10(2)mm(2) for the rural school. For all of the children monitored, the lowest particle number concentrations are found during sleeping time and the highest were found during eating time. With regard to alveolar deposited surface area dose, a child's home was the major contributor (about 70%), with school contributing about 17% for urban schools and 27% for the rural school. An important contribution arises from the cooking/eating time spent at home, which accounted for approximately 20% of overall exposure, corresponding to more than 200 mm(2). These activities represent the highest dose received per time unit, with very high values also encountered by children with a fireplace at home, as well as those that spend considerable time stuck in traffic jams. PMID:23000716

  11. Skin exposure to micro- and nano-particles can cause haemostasis in zebrafish larvae.

    PubMed

    McLeish, Jennifer A; Chico, Timothy J A; Taylor, Harriet B; Tucker, Carl; Donaldson, Ken; Brown, Simon B

    2010-04-01

    Low mass ambient exposure to airborne particles is associated with atherothrombotic events that may be a consequence of the combustion-derived nanoparticle content. There is concern also over the potential cardiovascular impact of manufactured nanoparticles. To better understand the mechanism by which toxic airborne particles can affect cardiovascular function we utilised zebrafish as a genetically tractable model. Using light and confocal fluorescence video-microscopy, we measured heart-rate and blood flow in the dorsal aorta and caudal artery of zebrafish larvae that had been exposed to a number of toxic and non-toxic microparticles and nanoparticles. Diesel exhaust particles (DEP), carboxy-charged Latex beads (carboxy-beads) and toxic alumina (Taimicron TM300), but not non-toxic alumina (Baikalox A125), were found to promote both skin and gut cell damage, increased leukocyte invasion into the epidermis, tail muscle ischaemia and haemostasis within the caudal artery of free swimming zebrafish larvae. The presence of sodium sulfite, a reducing agent, or warfarin, an anticoagulant, within the system water abrogated the effects of both toxic alumina and carboxy-beads but not DEP. Genetic manipulation of skin barrier function augmented skin damage and haemostasis, even for the non-toxic alumina. The toxic effects of carboxy-beads were still apparent after leukocyte numbers were depleted with anti-Pu.1 morpholino. We conclude that particle uptake across skin epithelium and gut mucosal barriers, or the presence of leukocytes, is not required for particle-induced haemostasis while a compromised skin barrier function accentuated tissue injury and haemostasis. PMID:20174755

  12. Enriched inorganic compounds in diesel exhaust particles induce mitogen-activated protein kinase activation, cytoskeleton instability, and cytotoxicity in human bronchial epithelial cells.

    PubMed

    Seriani, Robson; Junqueira, Mara S; Carvalho-Sousa, Claudia E; Arruda, Alessandra C T; Martinez, Diana; Alencar, Adriano M; Garippo, Ana L; Brito, Jôse Mara; Martins, Milton A; Saldiva, Paulo H N; Negri, Elnara M; Mauad, Thais; Macchione, Mariangela

    2015-04-01

    This study assessed the effects of the diesel exhaust particles on ERK and JNK MAPKs activation, cell rheology (viscoelasticity), and cytotoxicity in bronchial epithelial airway cells (BEAS-2B). Crude DEP and DEP after extraction with hexane (DEP/HEX) were utilized. The partial reduction of some DEP/HEX organics increased the biodisponibility of many metallic elements. JNK and ERK were activated simultaneously by crude DEP with no alterations in viscoelasticity of the cells. Mitochondrial activity, however, revealed a decrease through the MTT assay. DEP/HEX treatment increased viscoelasticity and cytotoxicity (membrane damage), and also activated JNK. Our data suggest that the greater bioavailability of metals could be involved in JNK activation and, consequently, in the reduction of fiber coherence and increase in the viscoelasticity and cytotoxicity of BEAS cells. The adverse findings detected after exposure to crude DEP and to DEP/HEX reflect the toxic potential of diesel compounds. Considering the fact that the cells of the respiratory epithelium are the first line of defense between the body and the environment, our data contribute to a better understanding of the pathways leading to respiratory cell injury and provide evidence for the onset of or worsening of respiratory diseases caused by inorganic compounds present in DEP. PMID:25769681

  13. Comparison of the particle size distribution of heavy-duty diesel exhaust using a dilution tailpipe sampler and an in-plume sampler during on-road operation.

    PubMed

    Brown, J E; Clayton, M J; Harris, D B; King, F G

    2000-08-01

    Originally constructed to develop gaseous emission factors for heavy-duty diesel trucks, the U.S. Environmental Protection Agency's (EPA) On-Road Diesel Emissions Characterization Facility has been modified to incorporate particle measurement instrumentation. An electrical low-pressure impactor designed to continuously measure and record size distribution data was used to monitor the particle size distribution of heavy-duty diesel truck exhaust. For this study, which involved a high-mileage (900,000 mi) truck running at full load, samples were collected by two different methods. One sample was obtained directly from the exhaust stack using an adaptation of the University of Minnesota's air-ejector-based mini-dilution sampler. The second sample was pulled from the plume just above the enclosed trailer, at a point approximately 11 m from the exhaust discharge. Typical dilution ratios of about 300:1 were obtained for both the dilution and plume sampling systems. Hundreds of particle size distributions were obtained at each sampling location. These were compared both selectively and cumulatively to evaluate the performance of the dilution system in simulating real-world exhaust plumes. The data show that, in its current residence-time configuration, the dilution system imposes a statistically significant bias toward smaller particles, with substantially more nanoparticles being collected than from the plume sample. PMID:11002602

  14. Effects on symptoms and lung function in humans experimentally exposed to diesel exhaust.

    PubMed Central

    Rudell, B; Ledin, M C; Hammarström, U; Stjernberg, N; Lundbäck, B; Sandström, T

    1996-01-01

    OBJECTIVES: Diesel exhaust is a common air pollutant made up of several gases, hydrocarbons, and particles. An experimental study was carried out which was designed to evaluate if a particle trap on the tail pipe of an idling diesel engine would reduce effects on symptoms and lung function caused by the diesel exhaust, compared with exposure to unfiltered exhaust. METHODS: Twelve healthy non-smoking volunteers (aged 20-37) were investigated in an exposure chamber for one hour during light work on a bicycle ergometer at 75 W. Each subject underwent three separate double blind exposures in a randomised sequence: to air and to diesel exhaust with the particle trap at the tail pipe and to unfiltered diesel exhaust. Symptoms were recorded according to the Borg scale before, every 10 minutes during, and 30 minutes after the exposure. Lung function was measured with a computerised whole body plethysmograph. RESULTS: The ceramic wall flow particle trap reduced the number of particles by 46%, whereas other compounds were relatively constant. It was shown that the most prominent symptoms during exposure to diesel exhaust were irritation of the eyes and nose and an unpleasant smell increasing during exposure. Both airway resistance (R(aw)) and specific airway resistance (SR(aw)) increased significantly during the exposures to diesel exhaust. Despite the 46% reduction in particle numbers by the trap effects on symptoms and lung function were not significantly attenuated. CONCLUSION: Exposure to diesel exhaust caused symptoms and bronchoconstriction which were not significantly reduced by a particle trap. PMID:8943829

  15. Physicochemical characterisation of diesel exhaust particles: Factors for assessing biological activity

    NASA Astrophysics Data System (ADS)

    Bérubé, K. A.; Jones, T. P.; Williamson, B. J.; Winters, C.; Morgan, A. J.; Richards, R. J.

    A range of microscopy and analytical techniques have been used to investigate the physicochemical properties of diluted DEP that may be important in determining its biological activity. Transmission electron microscopy demonstrated four basic categories of particle morphology: (1) "spherulites" [individual particles]; (2) "chains" or "clusters" of spherulites; (3) "spherules", [large bodies of spherulites]; (4) "flake-like bodies". Image analysis of TEM photomicrographs determined empirical morphological parameters (30 nm mean spherulite diameter, aspect ratio 1.5, mean particle area 0.078 μm, equivalent spherical diameter 0.23 μm, roundness 2.76) and derived parameters (0.313 μm 2 surface area, 3.7 μm 2 pg surface area per mass and 0.042 μm 3 volume) of DEP. Distributions of the particle sizes by number showed 10.1% were ultrafine (<0.1 μm), 89.5% fine (0.1-2.0 μm), 0.4% coarse (>2.5 μm), but distributions based on a mass value were different (0.01% ultrafine; 52.6% fine, 47.4% coarse). In contrast, impacted DEP contained 60.87% ultrafine, 39.13% fine and 0% coarse particles by number. Field emission scanning electron microscopy of spherulites revealed smooth surfaces and flocculated spherules with large surface areas. Electron probe X-ray micro-analysis demonstrated the presence of C, O, Na, Mg, K, Al, Si, P, S, Cl, Ca along with a range of metals (Ti, Mn, Fe, Zn, Cr), that were heterogeneous in distribution. Inductively coupled plasma mass and atomic emission spectrometry identified Mg, P, Ca, Cr, Mn, Zn, Sr, Mo, Ba, Na, Fe, S, and Si as the mobile sorbed metals readily removed during sonication in water from DEP suspensions. X-ray Diffraction confirmed previous observations of the presence of nanometer sized crystallites of disordered graphite. Comparison of microscopy and analytical results between sonicated and impacted DEP revealed a physicochemical difference that must be taken into account in any toxicological investigations.

  16. Differential Responses upon Inhalation Exposure to Biodiesel versus Diesel Exhaust on Oxidative Stress, Inflammatory and Immune Outcomes

    EPA Science Inventory

    Biodiesel (BD) exhaust may have reduced adverse health effects due to lower mass emissions and reduced production of hazardous compounds compared to diesel exhaust. To investigate this possibility, we compared adverse effects in lungs and liver of BALB/cJ mice after inhalation ex...

  17. Municipal waste incinerators: air and biological monitoring of workers for exposure to particles, metals, and organic compounds

    PubMed Central

    Maitre, A; Collot-Fertey, D; Anzivino, L; Marques, M; Hours, M; Stoklov, M

    2003-01-01

    Aims: To evaluate occupational exposure to toxic pollutants at municipal waste incinerators (MWIs). Methods: Twenty nine male subjects working near the furnaces in two MWIs, and 17 subjects not occupationally exposed to combustion generated pollutants were studied. Individual air samples were taken throughout the shift; urine samples were collected before and after. Stationary air samples were taken near potential sources of emission. Results: Occupational exposure did not result in the infringement of any occupational threshold limit value. Atmospheric exposure levels to particles and metals were 10–100 times higher in MWIs than at the control site. The main sources were cleaning operations for particles, and residue transfer and disposal operations for metals. MWI workers were not exposed to higher levels of polycyclic aromatic hydrocarbons than workers who are routinely in contact with vehicle exhaust. The air concentrations of volatile organic compounds and aldehydes were low and did not appear to pose any significant threat to human health. Only the measurement of chlorinated hydrocarbon levels would seem to be a reliable marker for the combustion of plastics. Urine metal levels were significantly higher at plant 1 than at plant 2 because of high levels of pollutants emanating from one old furnace. Conclusion: While biological monitoring is an easy way of acquiring data on long term personal exposure, air monitoring remains the only method that makes it possible to identify the primary sources of pollutant emission which need to be controlled if occupational exposure and environmental pollution are to be reduced. PMID:12883016

  18. Concentrated ambient ultrafine particle exposure induces cardiac change in young healthy volunteers

    EPA Science Inventory

    Exposure to ambient ultrafine particles has been associated with cardiopulmonary toxicity and mortality. Adverse effects specifically linked to ultrafine particles include loss of sympathovagal balance and altered hemostasis. To characterize the effects of ultrafine particles in ...

  19. Transcription Factors in the Cellular Response to Charged Particle Exposure.

    PubMed

    Hellweg, Christine E; Spitta, Luis F; Henschenmacher, Bernd; Diegeler, Sebastian; Baumstark-Khan, Christa

    2016-01-01

    Charged particles, such as carbon ions, bear the promise of a more effective cancer therapy. In human spaceflight, exposure to charged particles represents an important risk factor for chronic and late effects such as cancer. Biological effects elicited by charged particle exposure depend on their characteristics, e.g., on linear energy transfer (LET). For diverse outcomes (cell death, mutation, transformation, and cell-cycle arrest), an LET dependency of the effect size was observed. These outcomes result from activation of a complex network of signaling pathways in the DNA damage response, which result in cell-protective (DNA repair and cell-cycle arrest) or cell-destructive (cell death) reactions. Triggering of these pathways converges among others in the activation of transcription factors, such as p53, nuclear factor κB (NF-κB), activated protein 1 (AP-1), nuclear erythroid-derived 2-related factor 2 (Nrf2), and cAMP responsive element binding protein (CREB). Depending on dose, radiation quality, and tissue, p53 induces apoptosis or cell-cycle arrest. In low LET radiation therapy, p53 mutations are often associated with therapy resistance, while the outcome of carbon ion therapy seems to be independent of the tumor's p53 status. NF-κB is a central transcription factor in the immune system and exhibits pro-survival effects. Both p53 and NF-κB are activated after ionizing radiation exposure in an ataxia telangiectasia mutated (ATM)-dependent manner. The NF-κB activation was shown to strongly depend on charged particles' LET, with a maximal activation in the LET range of 90-300 keV/μm. AP-1 controls proliferation, senescence, differentiation, and apoptosis. Nrf2 can induce cellular antioxidant defense systems, CREB might also be involved in survival responses. The extent of activation of these transcription factors by charged particles and their interaction in the cellular radiation response greatly influences the destiny of the irradiated and also

  20. Nitrophenols isolated from diesel exhaust particles regulate steroidogenic gene expression and steroid synthesis in the human H295R adrenocortical cell line

    SciTech Connect

    Furuta, Chie; Noda, Shiho; Li Chunmei; Suzuki, Akira K; Taneda, Shinji; Watanabe, Gen; Taya, Kazuyoshi

    2008-05-15

    Studies of nitrophenols isolated from diesel exhaust particles (DEPs), 3-methyl-4-nitrophenol (PNMC) and 4-nitro-3-phenylphenol (PNMPP) have revealed that these chemicals possess estrogenic and anti-androgenic activity in vitro and in vivo and that PNMC accumulate in adrenal glands in vivo. However, the impacts of exposure to these compounds on adrenal endocrine disruption and steroidogenesis have not been investigated. To elucidate the non-receptor mediated effects of PNMC and PNMPP, we investigated the production of the steroid hormones progesterone, cortisol, testosterone, and estradiol-17{beta} and modulation of nine major enzyme genes involved in the synthesis of steroid hormones (CYP11A, CYP11B1, CYP17, CYP19, 17{beta}HSD1, 17{beta}HSD4, CYP21, 3{beta}HSD2, StAR) in human adrenal H295R cells supplied with cAMP. Exposure to 10{sup -7} to 10{sup -5} M PNMC and 1 mM 8-Br-cAMP for 48 h decreased testosterone, cortisol, and estradiol-17{beta} levels and increased progesterone secretion. At 10{sup -5} M, PNMC with 1 mM 8-Br-cAMP significantly stimulated expression of the 17{beta}HSD4 and significantly suppressed expression of 3{beta}HSD2. In comparison, 10{sup -7} to 2 x 10{sup -5} M PNMPP with 1 mM 8-Br-cAMP for 48 h decreased concentrations of estradiol-17{beta}, increased progesterone levels, but did not affect testosterone and cortisol secretion due to the significant suppression of CYP17 and the non-significant but obvious suppression of CYP19. Our results clarified steroidogenic enzymes as candidates responsible for the inhibition or stimulation for the production of steroid hormones in the steroidogenic pathway, thus providing the first experimental evidence for multiple mechanisms of disruption of endocrine pathways by these nitrophenols.

  1. Aryl hydrocarbon receptor-dependent upregulation of Cyp1b1 by TCDD and diesel exhaust particles in rat brain microvessels

    PubMed Central

    2011-01-01

    Background AhR activates the transcription of several target genes including CYP1B1. Recently, we showed CYP1B1 as the major cytochrome P450 (CYP) enzyme expressed in human brain microvessels. Here, we studied the effect of AhR activation by environmental pollutants on the expression of Cyp1b1 in rat brain microvessels. Methods Expression of AhR and Cyp1b1 was detected in isolated rat brain microvessels. AhR was immunovisualised in brain microvessel endothelial cells. The effect of AhR ligands on Cyp1b1 expression was studied using isolated brain microvessels after ex vivo and/or in vivo exposure to TCDD, heavy hydrocarbons containing diesel exhaust particles (DEP) or Δ9-tetrahydrocannabinol (Δ9-THC). Results After ex vivo exposure to TCDD (a highly potent AhR ligand) for 3 h, Cyp1b1 expression was significantly increased by 2.3-fold in brain microvessels. A single i.p. dose of TCDD also increased Cyp1b1 transcripts (22-fold) and Cyp1b1 protein (2-fold) in rat brain microvessels at 72 h after TCDD. Likewise, DEP treatment (in vivo and ex vivo) strongly induced Cyp1b1 protein in brain microvessels. DEP-mediated Cyp1b1 induction was inhibited by actinomycin D, cycloheximide, or by an AhR antagonist. In contrast, a sub-chronic in vivo treatment with Δ9-THC once daily for 7 seven days had no effect on Cyp1b1 expression Conclusions Our results show that TCDD and DEP strongly induced Cyp1b1 in rat brain microvessels, likely through AhR activation. PMID:21867498

  2. Reactive oxygen species- and nitric oxide-mediated lung inflammation and mitochondrial dysfunction in wild-type and iNOS-deficient mice exposed to diesel exhaust particles.

    PubMed

    Zhao, Hongwen; Ma, Joseph K; Barger, Mark W; Mercer, Robert R; Millecchia, Lyndell; Schwegler-Berry, Diane; Castranova, Vince; Ma, Jane Y

    2009-01-01

    Pulmonary responses to diesel exhaust particles (DEP) exposure are mediated through enhanced production of reactive oxygen species (ROS) and nitric oxide (NO) by alveolar macrophages (AM). The current study examined the differential roles of ROS and NO in DEP-induced lung injury using C57B/6J wild-type (WT) and inducible NO synthase knockout (iNOS KO) mice. Mice exposed by pharyngeal aspiration to DEP or carbon black particles (CB) (35 mg/kg) showed an inflammatory profile that included neutrophil infiltration, increased lactate dehydrogenase (LDH) activity, and elevated albumin content in bronchoalveolar lavage fluid (BALF) at 1, 3, and 7 d postexposure. The organic extract of DEP (DEPE) did not induce an inflammatory response. Comparing WT to iNOS KO mice, the results show that NO enhanced DEP-induced neutrophils infiltration and plasma albumin content in BALF and upregulated the production of the pro-inflammatory cytokine interleukin 12 (IL-12) by AM. DEP-exposed AM from iNOS KO mice displayed diminished production of IL-12 and, in response to ex vivo lipopolysaccharide (LPS) challenge, decreased production of IL-12 but increased production of IL-10 when compared to cells from WT mice. DEP, CB, but not DEPE, induced DNA damage and mitochondria dysfunction in AM, however, that is independent of cellular production of NO. These results demonstrate that DEP-induced immune/inflammatory responses in mice are regulated by both ROS- and NO-mediated pathways. NO did not affect ROS-mediated mitochondrial dysfunction and DNA damage but upregulated IL-12 and provided a counterbalance to the ROS-mediated adaptive stress response that downregulates IL-12 and upregulates IL-10. PMID:19267316

  3. Design and testing of electrostatic aerosol in vitro exposure system (EAVES): An alternative exposure system for particles

    EPA Science Inventory

    Conventional in vitro exposure methods for cultured human lung cells rely on prior suspension of particles in a liquid medium; these have limitations for exposure intensity and may modify the particle composition. Here electrostatic precipitation was used as an effective method f...

  4. Shielding from Solar Particle Event Exposures in Deep Space

    NASA Technical Reports Server (NTRS)

    Wilson, John W.; Cucinotta, F. A.; Shinn, J. L.; Simonsen, L. C.; Dubey, R. R.; Jordan, W. R.; Jones, T. D.; Chang, C. K.; Kim, M. Y.

    1999-01-01

    The physical composition and intensities of solar particle event exposures or sensitive astronaut tissues are examined under conditions approximating an astronaut in deep space. Response functions for conversion of particle fluence into dose and dose equivalent averaged over organ tissue, are used to establish significant fluence levels and the expected dose and dose rates of the most important events from past observations. The BRYNTRN transport code is used to evaluate the local environment experienced by sensitive tissues and used to evaluate bioresponse models developed for use in tactical nuclear warfare. The present results will help to the biophysical aspects of such exposure in the assessment of RBE and dose rate effects and their impact on design of protection systems for the astronauts. The use of polymers as shielding material in place of an equal mass of aluminum would prowide a large safety factor without increasing the vehicle mass. This safety factor is sufficient to provide adequate protection if a factor of two larger event than has ever been observed in fact occurs during the mission.

  5. Rat inhalation test with particles from biomass combustion and biomass co-firing exhaust

    NASA Astrophysics Data System (ADS)

    Bellmann, B.; Creutzenberg, O.; Ernst, H.; Muhle, H.

    2009-02-01

    The health effects of 6 different fly ash samples from biomass combustion plants (bark, wood chips, waste wood, and straw), and co-firing plants (coal, co-firing of coal and sawdust) were investigated in a 28-day nose-only inhalation study with Wistar WU rats. Respirable fractions of carbon black (Printex 90) and of titanium dioxide (Bayertitan T) were used as reference materials for positive and negative controls. The exposure was done 6 hours per day, 5 days per week at an aerosol concentration of 16 mg/m3. The MMAD of all fly ash samples and reference materials in the inhalation unit were in the range from 1.5 to 3 μm. The investigations focused predominantly on the analysis of inflammatory effects in the lungs of rats using bronchoalveolar lavage (BAL) and histopathology. Different parameters (percentage of polymorphonuclear neutrophils (PMN), interleukin-8 and interstitial inflammatory cell infiltration in the lung tissue) indicating inflammatory effects in the lung, showed a statistically significant increase in the groups exposed to carbon black (positive control), C1 (coal) and C1+BM4 (co-firing of coal and sawdust) fly ashes. Additionally, for the same groups a statistically significant increase of cell proliferation in the lung epithelium was detected. No significant effects were detected in the animal groups exposed to BM1 (bark), BM2 (wood chips), BM3 (waste wood), BM6 (straw) or titanium dioxide.

  6. Sensitive and selective detection of urinary 1-nitropyrene metabolites following administration of a single intragastric dose of diesel exhaust particles (SRM 2975) to rats.

    PubMed

    van Bekkum, Y M; van den Broek, P H; Scheepers, P T; Bos, R P

    1998-11-01

    1-Nitropyrene (1-NP) has been proposed as a marker for exposure to diesel exhaust particles (DEP). Since the extent of the actual intake of 1-NP adsorbed on DEP will be relatively low, sensitive and selective methods are needed regarding human exposure assessment. Two analytical methods are presented for the assessment of 1-NP metabolites in urine of male Sprague-Dawley rats administered a single intragastric dose of native DEP (SRM 2975, 20 mg, 35.7 microgram of 1-NP/g). Enzymatically hydrolyzed urine was extracted using Blue Rayon. The extracts were analyzed directly, using HPLC with postcolumn on-line reduction and fluorescence detection (HPLC-Flu), or were processed further for GC/MS/MS analysis. Although sensitive to several metabolites, the HPLC-Flu method lacked selectivity for quantitation of some important metabolites in rat urinary extracts, and therefore seems suitable for screening purposes only. With regard to GC/MS/MS analysis, derivatization with heptafluorobutyrylimidazole (HFBI) yielded low limits of determination for hydroxy-1-aminopyrenes, hydroxy-N-acetyl-1-aminopyrenes (converted to derivatized hydroxy-1-aminopyrenes by the reagent), and 1-aminopyrene (1.8-9.2 fmol on the column). Derivatization of hydroxy-1-nitropyrenes yielded relatively high limits of determination, and therefore, hydroxy-1-nitropyrenes were reduced to hydroxy-1-aminopyrenes prior to derivatization with HFBI. Intragastric administration of DEP to rats resulted in urinary excretion of 6-hydroxy-N-acetyl-1-aminopyrene, 8-hydroxy-N-acetyl-1-aminopyrene, 6-hydroxy-1-nitropyrene, 8-hydroxy-1-nitropyrene, and 3-hydroxy-1-nitropyrene (7, 1.2, 1.6, 0.3, and 0.5% of the dose within 12 h, respectively). 1-Nitropyrene, N-acetyl-1-aminopyrene, and 3-, 6-, and 8-hydroxy-1-aminopyrene were not observed as urinary metabolites following administration of a single dose of DEP. The observed excretion pattern and urinary metabolite concentrations suggest that 1-NP present on unmodified DEP

  7. Transcription Factors in the Cellular Response to Charged Particle Exposure

    PubMed Central

    Hellweg, Christine E.; Spitta, Luis F.; Henschenmacher, Bernd; Diegeler, Sebastian; Baumstark-Khan, Christa

    2016-01-01

    Charged particles, such as carbon ions, bear the promise of a more effective cancer therapy. In human spaceflight, exposure to charged particles represents an important risk factor for chronic and late effects such as cancer. Biological effects elicited by charged particle exposure depend on their characteristics, e.g., on linear energy transfer (LET). For diverse outcomes (cell death, mutation, transformation, and cell-cycle arrest), an LET dependency of the effect size was observed. These outcomes result from activation of a complex network of signaling pathways in the DNA damage response, which result in cell-protective (DNA repair and cell-cycle arrest) or cell-destructive (cell death) reactions. Triggering of these pathways converges among others in the activation of transcription factors, such as p53, nuclear factor κB (NF-κB), activated protein 1 (AP-1), nuclear erythroid-derived 2-related factor 2 (Nrf2), and cAMP responsive element binding protein (CREB). Depending on dose, radiation quality, and tissue, p53 induces apoptosis or cell-cycle arrest. In low LET radiation therapy, p53 mutations are often associated with therapy resistance, while the outcome of carbon ion therapy seems to be independent of the tumor’s p53 status. NF-κB is a central transcription factor in the immune system and exhibits pro-survival effects. Both p53 and NF-κB are activated after ionizing radiation exposure in an ataxia telangiectasia mutated (ATM)-dependent manner. The NF-κB activation was shown to strongly depend on charged particles’ LET, with a maximal activation in the LET range of 90–300 keV/μm. AP-1 controls proliferation, senescence, differentiation, and apoptosis. Nrf2 can induce cellular antioxidant defense systems, CREB might also be involved in survival responses. The extent of activation of these transcription factors by charged particles and their interaction in the cellular radiation response greatly influences the destiny of the irradiated and also

  8. Characteristics of aerosol particles and trace gases in ship exhaust plumes

    NASA Astrophysics Data System (ADS)

    Drewnick, F.; Diesch, J.; Borrmann, S.

    2011-12-01

    Gaseous and particulate matter from marine vessels gain increasing attention due to their significant contribution to the anthropogenic burden of the atmosphere, implying the change of the atmospheric composition and the impact on local and regional air quality and climate (Eyring et al., 2010). As ship emissions significantly affect air quality of onshore regions, this study deals with various aspects of gas and particulate plumes from marine traffic measured near the Elbe river mouth in northern Germany. In addition to a detailed investigation of the chemical and physical particle properties from different types of commercial marine vessels, we will focus on the chemistry of ship plumes and their changes while undergoing atmospheric processing. Measurements of the ambient aerosol, various trace gases and meteorological parameters using a mobile laboratory (MoLa) were performed on the banks of the Lower Elbe which is passed on average, daily by 30 ocean-going vessels reaching the port of Hamburg, the second largest freight port of Europe. During 5 days of sampling from April 25-30, 2011 170 commercial marine vessels were probed at a distance of about 1.5-2 km with high temporal resolution. Mass concentrations in PM1, PM2.5 and PM10 and number as well as PAH and black carbon (BC) concentrations in PM1 were measured; size distribution instruments covered the size range from 6 nm up to 32 μm. The chemical composition of the non-refractory aerosol in the submicron range was measured by means of an Aerosol Mass Spectrometer (Aerodyne HR-ToF-AMS). Gas phase species analyzers monitored various trace gas concentrations in the air and a weather station provided meteorological parameters. Additionally, a wide spectrum of ship information for each vessel including speed, size, vessel type, fuel type, gross tonnage and engine power was recorded via Automatic Identification System (AIS) broadcasts. Although commercial marine vessels powered by diesel engines consume high

  9. Exposure to wear particles generated from studded tires and pavement induces inflammatory cytokine release from human macrophages.

    PubMed

    Lindbom, John; Gustafsson, Mats; Blomqvist, Göran; Dahl, Andreas; Gudmundsson, Anders; Swietlicki, Erik; Ljungman, Anders G

    2006-04-01

    Health risks associated with exposure to airborne particulate matter (PM) have been shown epidemiologically as well as experimentally, pointing to both respiratory and cardiovascular effects. Lately, wear particles generated from traffic have been recognized to be a major contributing source to the overall particle load, especially in the Nordic countries were studded tires are used. In this work, we investigated the inflammatory effect of PM10 generated from the wear of studded tires on two different types of pavement. As comparison, we also investigated PM10 from a traffic-intensive street, a subway station, and diesel exhaust particles (DEP). Human monocyte-derived macrophages, nasal epithelial cells (RPMI 2650), and bronchial epithelial cells (BEAS-2B) were exposed to the different types of particles, and the secretion of IL-6, IL-8, IL-10, and TNF-alpha into the culture medium was measured. The results show a significant release of cytokines from macrophages after exposure for all types of particles. When particles generated from asphalt/granite pavement were compared to asphalt/quartzite pavement, the granite pavement had a significantly higher capacity to induce the release of cytokines. The granite pavement particles induced cytokine release at the same magnitude as the street particles did, which was higher than what particles from both a subway station and DEP did. Exposure of epithelial cells to PM10 resulted in a significant increase of TNF-alpha secreted from BEAS-2B cells for all types of particles used (DEP was not tested), and the highest levels were induced by subway particles. None of the particle types were able to evoke detectable cytokine release from RPMI 2650 cells. The results indicate that PM10 generated by the wear of studded tires on the street surface is a large contributor to the cytokine-releasing ability of particles in traffic-intensive areas and that the type of pavement used is important for the level of this contribution

  10. Human exposure to large solar particle events in space

    NASA Technical Reports Server (NTRS)

    Townsend, L. W.; Wilson, J. W.; Shinn, J. L.; Curtis, S. B.

    1992-01-01

    Whenever energetic solar protons produced by solar particle events traverse bulk matter, they undergo various nuclear and atomic collision processes which significantly alter the physical characteristics and biologically important properties of their transported radiation fields. These physical interactions and their effect on the resulting radiation field within matter are described within the context of a recently developed deterministic, coupled neutron-proton space radiation transport computer code (BRYNTRN). Using this computer code, estimates of human exposure in interplanetary space, behind nominal (2 g/sq cm) and storm shelter (20 g/sq cm) thicknesses of aluminum shielding, are made for the large solar proton event of August 1972. Included in these calculations are estimates of cumulative exposures to the skin, ocular lens, and bone marrow as a function of time during the event. Risk assessment in terms of absorbed dose and dose equivalent is discussed for these organs. Also presented are estimates of organ exposures for hypothetical, worst-case flare scenarios. The rate of dose equivalent accumulation places this situation in an interesting region of dose rate between the very low values of usual concern in terrestrial radiation environments and the high-dose-rate values prevalent in radiation therapy.

  11. Nose-only exposure system for inhalation exposures of rodents to large particles

    SciTech Connect

    Yeh, H.C.; Snipes, M.B.; Brodbeck, R.D.

    1987-03-01

    A large-particle exposure system for animals was designed, constructed and evaluated. The system was designed by incorporating a fluidized bed aerosol generator (FBG) and a nose-only exposure device to accommodate 40 small animals into a single unit. The system has four levels of exposure ports, each level having ten exposure ports radially positioned around the aerosol delivery components of the system. The aerosol generator produces aerosols that travel to the top of the system then downwards in order to be drawn past each animal's nose via vacuum ports immediately above the exposure ports. Nearly monodisperse polystyrene latex aerosols with nominal sizes of 3.0, 9.0 and 15.0 ..mu..m were generated as dry powders in an FBG with an inside diameter of 5 cm. During 60-min test runs, average aerosol mass concentrations up to 37 mg/m/sup 3/ were achieved with less than 10% variation in mass concentration distribution throughout the unit.

  12. The Role of MAC1 in Diesel Exhaust Particle-induced Microglial Activation and Loss of Dopaminergic Neuron Function

    PubMed Central

    Levesque, Shannon; Taetzsch, Thomas; Lull, Melinda E.; Johnson, Jo Anne; McGraw, Constance; Block, Michelle L.

    2013-01-01

    Increasing reports support that air pollution causes neuroinflammation and is linked to central nervous system (CNS) disease/damage. Diesel exhaust particles (DEP) are a major component of urban air pollution, which has been linked to microglial activation and Parkinson’s disease-like pathology. To begin to address how DEP may exert CNS effects, microglia and neuron-glia cultures were treated with either nanometer-sized DEP (<0.22 µM; 50µg/mL), ultrafine carbon black (ufCB, 50µg/ml), or DEP extracts (eDEP; from 50 µg/ml DEP) and the effect of microglial activation and dopaminergic (DA) neuron function was assessed. All three treatments showed enhanced amoeboid microglia morphology, increased H2O2 production, and decreased DA uptake. Mechanistic inquiry revealed that the scavenger receptor inhibitor fucoidan blocked DEP internalization in microglia, but failed to alter DEP-induced H2O2 production in microglia. However, pretreatment with the MAC1/CD11b inhibitor antibody blocked microglial H2O2 production in response to DEP. MAC1−/− mesencephalic neuron-glia cultures were protected from DEP-induced loss of DA neuron function, as measured by DA uptake. These findings support that DEP may activate microglia through multiple mechanisms, where scavenger receptors regulate internalization of DEP and the MAC1 receptor is mandatory for both DEP-induced microglial H2O2 production and loss of DA neuron function. PMID:23470120

  13. Size-segregated emissions and metal content of vehicle-emitted particles as a function of mileage: Implications to population exposure.

    PubMed

    Golokhvast, Kirill S; Chernyshev, Valery V; Chaika, Vladimir V; Ugay, Sergey M; Zelinskaya, Elena V; Tsatsakis, Aristidis M; Karakitsios, Spyros P; Sarigiannis, Denis A

    2015-10-01

    The study aims at investigating the characteristics (size distribution, active surface and metal content) of particles emitted by cars as a function of mileage using a novel methodology for characterizing particulate emissions captured by Exhaust Gas Suspension (EGS). EGS was obtained by passing the exhaust gases through a container of deionized water. EGS analysis was performed using laser granulometry, electron scanning microscopy, and high resolution mass spectrometry. Implications of the differences in key features of the emitted particles on population exposure were investigated using numerical simulation for estimating size-segregated PM deposition across human respiratory tract (HRT). It was found that vehicle mileage, age and the respective emissions class have almost no effect on the size distribution of the exhaust gas particulate released into the environment; about half of the examined vehicles with low mileage were found to release particles of aerodynamic diameter above 10 μm. The exhaust gas particulate detected in the EGS of all cars can be classified into three major size classes: (1) 0.1-5 µm - soot and ash particles, metals (Au, Pt, Pd, Ir); (2) 10-30 µm - metal (Cr, Fe, Cu, Zr, Ni) and ash particles; (3) 400-1,000 µm - metal (Fe, Cr, Pb) and ash particles. Newer vehicles with low mileage are substantial sources of soot and metal particles with median diameter of 200 nm with a higher surface area (up to 89,871.16 cm(2)/cm(3)). These tend to deposit in the lower part of the human respiratory tract. PMID:26264860

  14. Estimation of Exposure Levels for Consequences of Solar Particle Events

    NASA Technical Reports Server (NTRS)

    Kim, Myung-Hee Y.; Blattnig, Steve R.

    2016-01-01

    The potential for exposure to large solar particle events (SPEs) with fluxes that extend to high energies is a major concern during interplanetary transfer and extra-vehicular activities (EVAs) on the lunar and Martian surfaces. Prediction of sporadic occurrence of SPEs is not accurate for near or long term scales, while the expected frequency of such events is strongly influenced by solar cycle activity. In the development of NASA’s operational strategies real-time estimation of exposure to SPEs has been considered, so that adequate responses can be applied in a timely manner to reduce exposures to well below the exposure limits. Previously, the organ doses of large historical SPEs had been calculated by using the complete energy spectra of each event, and then developing a prediction model for blood forming organ (BFO) dose based solely on an assumed value of integrated fluence above 30 millielectronvolts (phi (sub 30)) for an otherwise unspecified future SPE. Since BFO dose is determined primarily by solar protons with high energies, it was reasoned that more accurate BFO dose prediction models could be developed using integrated fluence above 60 millielectronvolts (phi (sub 60)) and above 100 millielectronvolts (phi (sub 100)) as predictors instead of phi (sub 30) . In the current study, re-analysis of major SPEs, in which the proton spectra of the ground level enhancement (GLE) events since 1956 are correctly described by Band functions, has been utilized in evaluation of exposure levels. More accurate prediction models for BFO dose and NASA effective dose are then developed using integrated fluence above 200 millielectronvolts (phi (sub 200)), which by far have the most weight in the calculation of doses for deep-seated organs from exposure to extreme SPEs (GLEs or sub-GLEs). The unconditional probability of a BFO dose exceeding a pre-specified BFO dose limit is simultaneously calculated by taking into account the distribution of the predictor (phi (sub 30

  15. Exposure to Airborne Particles and Volatile Organic Compounds from Polyurethane Molding, Spray Painting, Lacquering, and Gluing in a Workshop

    PubMed Central

    Mølgaard, Bjarke; Viitanen, Anna-Kaisa; Kangas, Anneli; Huhtiniemi, Marika; Larsen, Søren Thor; Vanhala, Esa; Hussein, Tareq; Boor, Brandon E.; Hämeri, Kaarle; Koivisto, Antti Joonas

    2015-01-01

    Due to the health risk related to occupational air pollution exposure, we assessed concentrations and identified sources of particles and volatile organic compounds (VOCs) in a handcraft workshop producing fishing lures. The work processes in the site included polyurethane molding, spray painting, lacquering, and gluing. We measured total VOC (TVOC) concentrations and particle size distributions at three locations representing the various phases of the manufacturing and assembly process. The mean working-hour TVOC concentrations in three locations studied were 41, 37, and 24 ppm according to photo-ionization detector measurements. The mean working-hour particle number concentration varied between locations from 3000 to 36,000 cm−3. Analysis of temporal and spatial variations of TVOC concentrations revealed that there were at least four substantial VOC sources: spray gluing, mold-release agent spraying, continuous evaporation from various lacquer and paint containers, and either spray painting or lacquering (probably both). The mold-release agent spray was indirectly also a major source of ultrafine particles. The workers’ exposure can be reduced by improving the local exhaust ventilation at the known sources and by increasing the ventilation rate in the area with the continuous source. PMID:25849539

  16. Acute effects of exposure to 56Fe and 16O particles on learning and memory

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Although it has been shown that exposure to HZE particles disrupts cognitive performance when tested 2-4 weeks after irradiation, it has not been determined whether exposure to HZE particles can exert acute effects on cognitive performance; i.e., effects within 4-48 hrs after exposure. The present ...

  17. Urinary mutagenic activity in workers exposed to diesel exhaust

    SciTech Connect

    Schenker, M.B.; Samuels, S.J.; Kado, N.Y. ); Hammond, S.K.; Woskie, S.R.; Smith, T.J. )

    1992-04-01

    The authors measured postshift urinary mutagenicity on a population of railroad workers with a range of diesel exhaust exposures. Postshift urinary mutagenicity was determined by a sensitive microsuspension procedure using Salmonella strain TA 98 {plus minus} S9. Number of cigarettes smoked on the study day and urinary cotinine were highly correlated with postshift urinary mutagenicity. Diesel exhaust exposure was measured over the work shift by constant-flow personal sampling pumps. The relative ranking of jobs by this adjusted respirable particle concentration (ARP) was correlated with relative contact the job groups have with operating diesel locomotives. After adjustment for cigarette smoking in multiple regressions, there was no independent association of diesel exhaust exposure, as estimated by ARP, with postshift urinary mutagenicity among smokers or nonsmokers. An important finding is the detection of baseline mutagenicity in most of the nonsmoking workers. Despite the use of individual measurements of diesel exhaust exposure, the absence of a significant association in this study may be due to the low levels of diesel exposure, the lack of a specific marker for diesel exhaust exposure, and/or urinary mutagenicity levels from diesel exposure below the limit of sensitivity for the mutagenicity assay.

  18. Immune Exhaustion and Transplantation.

    PubMed

    Sanchez-Fueyo, A; Markmann, J F

    2016-07-01

    Exhaustion of lymphocyte function through chronic exposure to a high load of foreign antigen is well established for chronic viral infection and antitumor immunity and has been found to be associated with a distinct molecular program and characteristic cell surface phenotype. Although exhaustion has most commonly been studied in the context of CD8 viral responses, recent studies indicate that chronic antigen exposure may affect B cells, NK cells and CD4 T cells in a parallel manner. Limited information is available regarding the extent of lymphocyte exhaustion development in the transplant setting and its impact on anti-graft alloreactivity. By analogy to the persistence of a foreign virus, the large mass of alloantigen presented by an allograft in chronic residence could provide an ideal setting for exhausting donor-reactive T cells. The extent of T cell exhaustion occurring with various allografts, the kinetics of its development, whether exhaustion is influenced positively or negatively by different immunosuppressants, and the impact of exhaustion on graft survival and tolerance development remains a fertile area for investigation. Harnessing or encouraging the natural processes of exhaustion may provide a novel means to promote graft survival and transplantation tolerance. PMID:26729653

  19. Exposure to galactic cosmic radiation and solar energetic particles.

    PubMed

    O'Sullivan, D

    2007-01-01

    Several investigations of the radiation field at aircraft altitudes have been undertaken during solar cycle 23 which occurred in the period 1993-2003. The radiation field is produced by the passage of galactic cosmic rays and their nuclear reaction products as well as solar energetic particles through the Earth's atmosphere. Galactic cosmic rays reach a maximum intensity when the sun is least active and are at minimum intensity during solar maximum period. During solar maximum an increased number of coronal mass ejections and solar flares produce high energy solar particles which can also penetrate down to aircraft altitudes. It is found that the very complicated field resulting from these processes varies with altitude, latitude and stage of solar cycle. By employing several active and passive detectors, the whole range of radiation types and energies were encompassed. In-flight data was obtained with the co-operation of many airlines and NASA. The EURADOS Aircraft Crew in-flight data base was used for comparison with the predictions of various computer codes. A brief outline of some recent studies of exposure to radiation in Earth orbit will conclude this contribution. PMID:17846031

  20. Diesel Exhaust Particles Activate the Matrix-Metalloproteinase-1 Gene in Human Bronchial Epithelia in a β-Arrestin–Dependent Manner via Activation of RAS

    PubMed Central

    Li, Jinju; Ghio, Andrew J.; Cho, Seung-Hyun; Brinckerhoff, Constance E.; Simon, Sidney A.; Liedtke, Wolfgang

    2009-01-01

    Background Diesel exhaust particles (DEPs) are globally relevant air pollutants that exert a detrimental human health impact. However, mechanisms of damage by DEP exposure to human respiratory health and human susceptibility factors are only partially known. Matrix metalloproteinase-1 (MMP-1) has been implied as an (etio)pathogenic factor in human lung and airway diseases such as emphysema, chronic obstructive pulmonary disease, chronic asthma, tuberculosis, and bronchial carcinoma and has been reported to be regulated by DEPs. Objective We elucidated the molecular mechanisms of DEPs’ up-regulation of MMP-1. Methods/Results Using permanent and primary human bronchial epithelial (HBE) cells at air–liquid interface, we show that DEPs activate the human MMP-1 gene via RAS and subsequent activation of RAF-MEK-ERK1/2 mitogen-activated protein kinase signaling, which can be scaffolded by β-arrestins. Short interfering RNA mediated β-arrestin1/2 knockout eliminated formation, subsequent nuclear trafficking of phosphorylated ERK1/2, and resulting MMP-1 transcriptional activation. Transcriptional regulation of the human MMP-1 promoter was strongly influenced by the presence of the –1607GG polymorphism, present in 60–80% of humans, which led to striking up-regulation of MMP-1 transcriptional activation. Conclusion Our results confirm up-regulation of MMP-1 in response to DEPs in HBE and provide new mechanistic insight into how these epithelia, the first line of protection against environmental insults, up-regulate MMP-1 in response to DEP inhalation. These mechanisms include a role for the human –1607GG polymorphism as a susceptibility factor for an accentuated response, which critically depends on the ability of β-arrestin1/2 to generate scaffolding and nuclear trafficking of phosphorylated ERK1/2. PMID:19337515

  1. Interplanetary particle transport simulation for warning system for aviation exposure to solar energetic particles

    NASA Astrophysics Data System (ADS)

    Kubo, Yûki; Kataoka, Ryuho; Sato, Tatsuhiko

    2015-07-01

    Solar energetic particles (SEPs) are one of the extreme space weather phenomena. A huge SEP event increases the radiation dose received by aircrews, who should be warned of such events as early as possible. We developed a warning system for aviation exposure to SEPs. This article describes one component of the system, which calculates the temporal evolution of the SEP intensity and the spectrum immediately outside the terrestrial magnetosphere. To achieve this, we performed numerical simulations of SEP transport in interplanetary space, in which interplanetary SEP transport is described by the focused transport equation. We developed a new simulation code to solve the equation using a set of stochastic differential equations. In the code, the focused transport equation is expressed in a magnetic field line coordinate system, which is a non-orthogonal curvilinear coordinate system. An inverse Gaussian distribution is employed as the injection profile of SEPs at an inner boundary located near the Sun. We applied the simulation to observed SEP events as a validation test. The results show that our simulation can closely reproduce observational data for the temporal evolution of particle intensity. By employing the code, we developed the WArning System for AVIation Exposure to Solar energetic particles (WASAVIES).

  2. Exposure to wood smoke particles produces an inflammation in healthy volunteers

    EPA Science Inventory

    Background. Human exposure to wood smoke particles (WSP) is of consequence in indoor air quality, exposures from wild fires, burning ofbiomass, and air pollution. This investigation tested the postulate that healthy volunteers exposed to WSP would demonstrate pulmonary and cardio...

  3. UPREGULATION OF TISSUE FACTOR IN HUMAN ENDOTHELIAL CELLS FOLLOWING ULTRAFINE PARTICLE EXPOSURE

    EPA Science Inventory

    Epidemiology studies have linked the exposure to air pollutant particles with increased cardiovascular mortality and morbidity, but the mechanisms remain unknown. In our laboratory we have tested the hypothesis that the ultrafine fraction of ambient pollutant particles would cau...

  4. Different exposure of infants and adults to ultrafine particles in the urban area of Barcelona.

    PubMed

    Garcia-Algar, Oscar; Canchucaja, Lizzeth; d'Orazzio, Valentina; Manich, Andrea; Joya, Xavier; Vall, Oriol

    2015-01-01

    Air pollutants have been linked with a number of adverse health effects. Children are especially sensitive, particularly when they get close to the exhaust emissions of the vehicles on the street. The objective of this study was to measure the different exposure of infants and adults to ultrafine particles (UFP) as a surrogate marker of air pollution and of risk of deleterious health effects. Two different portable P-TRAK were used to measure simultaneously exposure to UFPs at different heights, one corresponding to the height of an infant in a stroller (0.55 m) and the other one to the height of the face of an adult pedestrian (1.70 m). Measurements were taken on three different streets with high traffic density in Barcelona, in 10 consecutive days during spring, with two sampling sessions of 1 h each day, moving afoot and taking into account temperature, humidity, and wind speed. Fifty-two thousand and eight (52,008) paired values were obtained, and the results showed about 10% higher levels of UFP concentration at 0.55 m (48,198 ± 25,296 pt/cm(3)) compared to 1.70 m (43,151 ± 22,517 pt/cm(3)). Differences between working and nonworking days were observed. Concentration patterns and variation by days of the week and time periods were related to traffic intensity. This study revealed that infants transported by stroller in urban areas are more exposed to air pollution than walking adults. As infants are more vulnerable and UFP have more effects on their health, measures should be taken to protect this population when it is transported in the street. PMID:25433547

  5. Hypotension and AV block after diesel exhaust exposure in heart failure-prone rats: role of gaseous and particulate components

    EPA Science Inventory

    Acute inhalations ofdiesel engine exhaust (DE) and fine particulate matter (PM2.5) have been demonstrated to provoke adverse cardiac events in humans with preexisting heart disease. Electrophysiologic dysfunction and autonomic imbalance are among the mechanisms widely held to und...

  6. Treadmill stress test after diesel exhaust particulate exposure reveals a time-dependent shift from parasympathetic to sympathetic dominance

    EPA Science Inventory

    Epidemiological studies suggest that particulate matter (PM) air pollution is a major trigger of acute cardiac events-including arrhythmia-especially in those with preexisting cardiac disease. Diesel exhaust (DE) contributes the majority of urban fine and ultrafine PM, and is thu...

  7. Traffic generated non-exhaust particulate emissions from concrete pavement: A mass and particle size study for two-wheelers and small cars

    NASA Astrophysics Data System (ADS)

    Aatmeeyata; Kaul, D. S.; Sharma, Mukesh

    This study aimed to understand the non-exhaust (NE) emission of particles from wear of summer tire and concrete pavement, especially for two wheelers and small cars. A fully enclosed laboratory-scale model was fabricated to simulate road tire interaction with a facility to collect particles in different sizes. A road was cast using the M-45 concrete mixture and the centrifugal casting method. It was observed that emission of large particle non exhaust emission (LPNE) as well as PM 10 and PM 2.5 increased with increasing load. The LPNE was 3.5 mg tire -1 km -1 for a two wheeler and 6.4 mg tire -1 km -1 for a small car. The LPNE can lead to water pollution through water run-off from the roads. The contribution of the PM 10 and PM 2.5 was smaller compared to the LPNE particles (less than 0.1%). About 32 percent of particle mass of PM 10 was present below 1 μm. The number as well as mass size distribution for PM 10 was observed to be bi-modal with peaks at 0.3 μm and 4-5 μm. The NE emissions did not show any significant trend with change in tire pressure.

  8. Exhaust purification apparatus

    SciTech Connect

    Shinzawa, M.; Ushimura, S.

    1987-05-05

    An exhaust purification apparatus is described for use in an internal combustion engine having an exhaust conduit through which exhaust particles are discharged together with exhaust gas to the atmosphere. Included is an outer shell having an inlet connected to the exhaust conduit and an outlet connected to the atmosphere. The outer shell contains a trap element and a regenerative burner located upstream of the trap element, the regenerative burner comprising: a cylindrical hollow member fixed to the liner and extending within a combustion chamber to define an evaporation chamber, a glow plug for igniting the mixture supplied into the evaporated chamber when actuated; and a control unit responsive to a regeneration requirement for actuating the glow plug and supplying an air-fuel mixture into the evaporation chamber through the mixture conduit.

  9. Glutathione-S-transferase M1 regulation of diesel exhaust particle-induced pro-inflammatory mediator expression in normal human bronchial epithelial cells

    PubMed Central

    2012-01-01

    Background Diesel exhaust particles (DEP) contribute substantially to ambient particulate matter (PM) air pollution in urban areas. Inhalation of PM has been associated with increased incidence of lung disease in susceptible populations. We have demonstrated that the glutathione S-transferase M1 (GSTM1) null genotype could aggravate DEP-induced airway inflammation in human subjects. Given the critical role airway epithelial cells play in the pathogenesis of airway inflammation, we established the GSTM1 deficiency condition in primary bronchial epithelial cells from human volunteers with GSTM1 sufficient genotype (GSTM1+) using GSTM1 shRNA to determine whether GSTM1 deficiency could exaggerate DEP-induced expression of interleukin-8 (IL-8) and IL-1β proteins. Furthermore, the mechanisms underlying GSTM1 regulation of DEP-induced IL-8 and IL-1β expression were also investigated. Methods IL-8 and IL-1β protein levels were measured using enzyme-linked immunosorbent assay. GSTM1 deficiency in primary human bronchial epithelial cells was achieved using lentiviral GSTM1 shRNA particles and verified using real-time polymerase chain reaction and immunoblotting. Intracellular reactive oxygen species (ROS) production was evaluated using flow cytometry. Phosphorylation of protein kinases was detected using immunoblotting. Results Exposure of primary human bronchial epithelial cells (GSTM1+) to 25-100 μg/ml DEP for 24 h significantly increased IL-8 and IL-1β protein expression. Knockdown of GSTM1 in these cells further elevated DEP-induced IL-8 and IL-1β expression, implying that GSTM1 deficiency aggravated DEP-induced pro-inflammatory response. DEP stimulation induced the phosphorylation of extracellular signal-regulated kinase (ERK) and Akt, the downstream kinase of phosphoinositide 3-kinase (PI3K), in GSTM1+ bronchial epithelial cells. Pharmacological inhibition of ERK kinase and PI3K activity blocked DEP-induced IL-8 and IL-1β expression. DEP-induced ERK and Akt

  10. ATTRIBUTION OF PARTICLE EXPOSURE AND RISK TO COMBUSTION SOURCE EMISSIONS BASED ON PERSONAL PAH EXPOSURE AND URINARY METABOLITES

    EPA Science Inventory

    Personal airborne exposures to carcinogenic particulate PAH have been significantly correlated with exposure to respirable fine particle mass (PM 2.5) in several studies. All combustion sources emit PAH, however the relative concentrations of different PAH and other organic tr...

  11. Solar system exposure histories of interplanetary dust particles

    NASA Technical Reports Server (NTRS)

    Nier, Alfred O.

    1994-01-01

    The topics discussed include the following: stratospheric collection of interplanetary dust particles (IDP's); sources of interplanetary dust particles; and solar wind and noble gas isotopic ratios in IDP's.

  12. Full Useful Life (120,000 miles) Exhaust Emission Performance of a NOx Adsorber and Diesel Particle Filter Equipped Passenger Car and Medium-duty Engine in Conjunction with Ultra Low Sulfur Fuel (Presentation)

    SciTech Connect

    Thornton, M.; Tatur, M.; Tomazic, D.; Weber, P.; Webb, C.

    2005-08-25

    Discusses the full useful life exhaust emission performance of a NOx (nitrogen oxides) adsorber and diesel particle filter equipped light-duty and medium-duty engine using ultra low sulfur diesel fuel.

  13. Airborne concentrations of PM(2.5) and diesel exhaust particles on Harlem sidewalks: a community-based pilot study.

    PubMed Central

    Kinney, P L; Aggarwal, M; Northridge, M E; Janssen, N A; Shepard, P

    2000-01-01

    Residents of the dense urban core neighborhoods of New York City (NYC) have expressed increasing concern about the potential human health impacts of diesel vehicle emissions. We measured concentrations of particulate matter [less than/equal to] 2.5 micro in aerodynamic diameter (PM(2.5)) and diesel exhaust particles (DEP) on sidewalks in Harlem, NYC, and tested whether spatial variations in concentrations were related to local diesel traffic density. Eight-hour (1000-1800 hr) air samples for PM(2.5 )and elemental carbon (EC) were collected for 5 days in July 1996 on sidewalks adjacent to four geographically distinct Harlem intersections. Samples were taken using portable monitors worn by study staff. Simultaneous traffic counts for diesel trucks, buses, cars, and pedestrians were carried out at each intersection on [Greater/equal to] 2 of the 5 sampling days. Eight-hour diesel vehicle counts ranged from 61 to 2,467 across the four sites. Mean concentrations of PM(2.5) exhibited only modest site-to-site variation (37-47 microg/m(3)), reflecting the importance of broader regional sources of PM(2.5). In contrast, EC concentrations varied 4-fold across sites (from 1.5 to 6 microg/m(3)), and were associated with bus and truck counts on adjacent streets and, at one site, with the presence of a bus depot. A high correlation (r = 0.95) was observed between EC concentrations measured analytically and a blackness measurement based on PM(2.5) filter reflectance, suggesting the utility of the latter as a surrogate measure of DEP in future community-based studies. These results show that local diesel sources in Harlem create spatial variations in sidewalk concentrations of DEP. The study also demonstrates the feasibility of a new paradigm for community-based research involving full and active partnership between academic scientists and community-based organizations. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 PMID:10706526

  14. HEMATOLOGICAL AND MOLECULAR CARDIAC EFFECTS FOLLOWING PULMONARY EXPOSURE TO OIL COMBUSTION PARTICLES

    EPA Science Inventory

    Hematological and Molecular Cardiac Effects Following Pulmonary Exposure to Oil Combustion Particles
    K. Dreher, R. Jaskot, and J. Richards. USEPA, Research Triangle Park, NC

    Systemic health effects induced following pulmonary exposure to various combustion particles are...

  15. PERSONAL EXPOSURE TO PARTICLES IN BANSKA BYSTRICA, SLOVAKIA

    EPA Science Inventory

    Epidemiological studies have associated adverse health impacts with ambient concentrations of particulate matter (PM), though these studies have been limited in their characterization of personal exposure to PM. An exposure study of healthy nonsmoking adults and children was cond...

  16. Circulating factors induce coronary endothelial cell activation following exposure to inhaled diesel exhaust and nitrogen dioxide in humans: evidence from a novel translational in vitro model.

    PubMed

    Channell, Meghan M; Paffett, Michael L; Devlin, Robert B; Madden, Michael C; Campen, Matthew J

    2012-05-01

    The vascular toxicity of inhaled agents may be caused by soluble factors that are released into the systemic circulation. To confirm this in a straightforward manner, we obtained plasma from healthy human volunteers before and after exposure to diesel exhaust (DE) and nitrogen dioxide (NO(2)). Plasma samples were obtained from human volunteers exposed to 100 μg/m(3) DE or filtered air for 2 h. A second cohort was exposed to 500 ppb NO(2) or filtered air in an identical protocol. Primary human coronary artery endothelial cells (hCAECs) were grown to confluence and treated for 24 h with a 10 or 30% (in media) mixture of plasma obtained before, immediately post or 24 h postexposure to pollutant exposures. Messenger RNA (mRNA) was isolated from hCAECs following the incubation and probed for intracellular cell adhesion molecule (ICAM-1) and vascular cell adhesion molecule (VCAM-1) expression. ICAM-1 mRNA expression was increased by plasma obtained at both timepoints following the NO(2) exposures. VCAM-1 was significantly elevated in cells treated with plasma obtained 24 h following diesel exposure and at both timepoints following NO(2) exposure. Interleukin-8 protein was elevated in the hCAEC supernatant when cells were incubated with plasma from NO(2) exposures. These data indicate that proinflammatory circulating factors are elevated acutely following exposure to both DE and a primary component thereof, NO(2). These functional translational assays offer novel approaches to assessing the cardiovascular risk associated with air pollution exposure. PMID:22331494

  17. Development of a two dimensional-high performance liquid chromatography-tandem mass spectrometry method to quantify nitro-PAHs in particulate matter and assess personal exposures to diesel exhaust

    NASA Astrophysics Data System (ADS)

    Miller-Schulze, Justin P.

    Ambient particulate matter (PM) is of concern to regulatory agencies due to its adverse impacts on public health. A significant contributor to ambient PM is diesel exhaust (as diesel particulate matter, DPM). Current methods for accurately quantifying ambient exposures to DPM are inadequate, as they employ markers that are not well-suited as specific markers for diesel exhaust or because they lack the selectivity and sensitivity to quantify the specific markers at ambient levels. To address this issue, a 2D-HPLC-MS/MS method was developed. This method exhibited novel sensitivity and selectivity for 1-nitropyrene (1NP), a specific molecular marker for diesel exhaust; in addition, this method was used to monitor two additional nitro-PAH species, 2-nitrofluoranthene and 2-nitropyrene, which are formed exclusively via secondary atmospheric reactions. This method was applied to four sets of filter samples from three different locations which were expected to represent three different classes of exposure to diesel exhaust. These locations were: Trujillo, Peru (high exposure); Shenyang, China (medium exposure); and Seattle, Washington (low exposure). The results of these analyses were congruent with what was anticipated due to existing knowledge of environmental regulations in these areas. In addition, urine samples were analyzed for urinary metabolites of 1NP in two of these groups; the Shenyang group and a Seattle group. Differences in the concentrations of 1NP metabolites were observed, although these differences were not of the same magnitude as the differences in 1NP exposures. The results of the filter analyses indicate that the 2D-HPLC-MS/MS method developed has adequate selectivity and sensitivity to detect trace levels of environmentally relevant nitro-PAH species in ambient PM samples. The results of the urine analysis indicate that while the 1NP metabolites detected may not be adequate as biomarkers of acute exposure to diesel exhaust, they may have potential

  18. Case report: Atrial fibrillation following exposure to ambient air pollution particles

    EPA Science Inventory

    CONTEXT: Exposure to air pollution can result in the onset of atrial fibrillation. CASE PRESENTATION: We present a case of a 58 year old woman who volunteered to participate in a controlled exposure to concentrated ambient particles (CAPs). Twenty minutes into the exposure, there...

  19. Prediction of frequency and exposure level of solar particle events.

    PubMed

    Kim, Myung-Hee Y; Hayat, Matthew J; Feiveson, Alan H; Cucinotta, Francis A

    2009-07-01

    For future space missions outside of the Earth's magnetic field, the risk of radiation exposure from solar particle events (SPEs) during extra-vehicular activities (EVAs) or in lightly shielded vehicles is a major concern when designing radiation protection including determining sufficient shielding requirements for astronauts and hardware. While the expected frequency of SPEs is strongly influenced by solar modulation, SPE occurrences themselves are chaotic in nature. We report on a probabilistic modeling approach, where a cumulative expected occurrence curve of SPEs for a typical solar cycle was formed from a non-homogeneous Poisson process model fitted to a database of proton fluence measurements of SPEs that occurred during the past 5 solar cycles (19-23) and those of large SPEs identified from impulsive nitrate enhancements in polar ice. From the fitted model, we then estimated the expected frequency of SPEs at any given proton fluence threshold with energy >30 MeV (Phi(30)) during a defined space mission period. Analytic energy spectra of 34 large SPEs observed in the space era were fitted over broad energy ranges extending to GeV, and subsequently used to calculate the distribution of mGy equivalent (mGy-Eq) dose for a typical blood-forming organ (BFO) inside a spacecraft as a function of total Phi(30) fluence. This distribution was combined with a simulation of SPE events using the Poisson model to estimate the probability of the BFO dose exceeding the NASA 30-d limit of 250 mGy-Eq per 30 d. These results will be useful in implementing probabilistic risk assessment approaches at NASA and guidelines for protection systems for astronauts on future space exploration missions. PMID:19509510

  20. DIESEL EXHAUST PARTICULATE (DEP)-INDUCED ACTIV ATION OF STAT3 REQUIRES ACTIVITIES OF EGFR AND SRC IN AIRWAY EPITHELIAL CELLS

    EPA Science Inventory

    In vivo exposure to diesel exhaust particles (DEP) elicits acute inflammatory responses in the lung characterized by inflammatory cell influx and elevated expression of mediators such as cytokines, and chemokines. Signal transducers and activators of transcription (STAT) protein...

  1. Ozone enhances diesel exhaust particles (DEP)-induced interleukin-8 (IL-8) gene expression in human airway epithelial cells through activation of nuclear factors- kappaB (NF-kappaB) and IL-6 (NF-IL6).

    PubMed

    Kafoury, Ramzi M; Kelley, James

    2005-12-01

    Ozone, a highly reactive oxidant gas is a major component of photochemical smog. As an inhaled toxicant, ozone induces its adverse effects mainly on the lung. Inhalation of particulate matter has been reported to cause airway inflammation in humans and animals. Furthermore, epidemiological evidence has indicated that exposure to particulate matter (PM[2.5-10]), including diesel exhaust particles (DEP) has been correlated with increased acute and chronic respiratory morbidity and exacerbation of asthma. Previously, exposure to ozone or particulate matter and their effect on the lung have been addressed as separate environmental problems. Ozone and particulate matter may be chemically coupled in the ambient air. In the present study we determined whether ozone exposure enhances DEP effect on interleukin-8 (IL-8) gene expression in human airway epithelial cells. We report that ozone exposure (0.5 ppm x 1 hr) significantly increased DEP-induced IL-8 gene expression in A549 cells (117 +/- 19 pg/ml, n = 6, p < 0.05) as compared to cultures treated with DEP (100 microg/ml x 4 hr) alone (31 +/- 3 pg/ml, n = 6), or cultures exposed to purified air (24 +/- 6 pg/ml, n = 6). The increased DEP-induced IL-8 gene expression following ozone exposure was attributed to ozone-induced increase in the activity of the transcription factors NF-kappaB and NF-IL6. The results of the present study indicate that ozone exposure enhances the toxicity of DEP in human airway epithelial cells by augmenting IL-8 gene expression, a potent chemoattractant of neutrophils in the lung. PMID:16819095

  2. Comparison of Algorithm-based Estimates of Occupational Diesel Exhaust Exposure to Those of Multiple Independent Raters in a Population-based Case–Control Study

    PubMed Central

    Friesen, Melissa C.

    2013-01-01

    Objectives: Algorithm-based exposure assessments based on patterns in questionnaire responses and professional judgment can readily apply transparent exposure decision rules to thousands of jobs quickly. However, we need to better understand how algorithms compare to a one-by-one job review by an exposure assessor. We compared algorithm-based estimates of diesel exhaust exposure to those of three independent raters within the New England Bladder Cancer Study, a population-based case–control study, and identified conditions under which disparities occurred in the assessments of the algorithm and the raters. Methods: Occupational diesel exhaust exposure was assessed previously using an algorithm and a single rater for all 14 983 jobs reported by 2631 study participants during personal interviews conducted from 2001 to 2004. Two additional raters independently assessed a random subset of 324 jobs that were selected based on strata defined by the cross-tabulations of the algorithm and the first rater’s probability assessments for each job, oversampling their disagreements. The algorithm and each rater assessed the probability, intensity and frequency of occupational diesel exhaust exposure, as well as a confidence rating for each metric. Agreement among the raters, their aggregate rating (average of the three raters’ ratings) and the algorithm were evaluated using proportion of agreement, kappa and weighted kappa (κw). Agreement analyses on the subset used inverse probability weighting to extrapolate the subset to estimate agreement for all jobs. Classification and Regression Tree (CART) models were used to identify patterns in questionnaire responses that predicted disparities in exposure status (i.e., unexposed versus exposed) between the first rater and the algorithm-based estimates. Results: For the probability, intensity and frequency exposure metrics, moderate to moderately high agreement was observed among raters (κw = 0.50–0.76) and between the

  3. On-road and laboratory investigations on non-exhaust ultrafine particles from the interaction between the tire and road pavement under braking conditions

    NASA Astrophysics Data System (ADS)

    Kwak, Jihyun; Lee, Sunyoup; Lee, Seokhwan

    2014-11-01

    We investigated the physical and chemical characteristics of non-exhaust ultrafine particles from on-road driving and laboratory measurements using a mobile sampling vehicle. The on-road driving and laboratory measurements during constant speed conditions revealed no enhancement of ultrafine particles. Under braking events, the total number concentrations of tire particles (TPs) sampled 90 mm above the road surface was 6 times higher with broader mode diameters when compared to 40 mm above the road surface. In contrast to braking events, under cornering conditions, the total number concentrations of TPs sampled 40 mm above the road surface were 50 times higher relative to 90 mm above the road surface. From the morphological and elemental analyses, it is likely that the ultrafine particles generated from the interaction between the tire and the road surface under braking conditions might originated from sulfur-containing materials or anti-oxidants which are contained in TPs, and/or graphite and solid lubricants which are mainly present in brake particles (BPs). However, Zn which was a distinguishing elemental marker of tire wear particles didn't show in EDS spectra. Further research would be required as to the exact emission source of ultrafine particles.

  4. Human Bronchial Epithelial Cell Response to Heavy Particle Exposure

    NASA Astrophysics Data System (ADS)

    Story, Michael; Ding, Liang-Hao; Minna, John; Park, Seong-mi; Peyton, Michael; Larsen, Jill

    2012-07-01

    A battery of non-oncogenically immortalized human bronchial epithelial cells (HBECs) are being used to examine the molecular changes that lead to lung carcinogenesis after exposure to heavy particles found in the free space environment. The goal is to ultimately identify biomarkers of radioresponse that can be used for prediction of carcinogenic risk for fatal lung cancer. Our initial studies have focused on the cell line HBEC3 KT and the isogenic variant HBEC3 KTR53, which overexpresses the RASv12 mutant and where p53 has been knocked down by shRNA, and is considered to be a more oncogenically progressed variant. We have previously described the response of HBEC3 KT at the cellular and molecular level, however, the focus here is on the rate of cellular transformation after HZE radiation exposure and the molecular changes in transformed cells. When comparing the two cell lines we find that there is a maximum rate of cellular transformation at 0.25 Gy when cells are exposed to 1 GeV Fe particles, and, for the HBEC3 KTR53 there are multiple pathways upregulated that promote anchorage independent growth including the mTOR pathway, the TGF-1 pathway, RhoA signaling and the ERK/MAPK pathway as early as 2 weeks after radiation. This does not occur in the HBEC3 KT cell line. Transformed HBEC3 KT cells do not show any morphologic or phenotypic changes when grown as cell cultures. HBEC3 KTR53 cells on the other hand show substantial changes in morphology from a cobblestone epithelial appearance to a mesenchymal appearance with a lack of contact inhibition. This epithelial to mesenchymal change in morphology is accompanied by the expression of vimentin and a reduction in the expression of E-cadherin, which are hallmarks of epithelial to mesenchymal transition. Interestingly, for HBEC3 KT transformed cells there are no mutations in the p53 gene, 2 of 15 clones were found to be heterozygous for the RASV12 mutation, and 3 of 15 clones expressed high levels of BigH3, a TGFB

  5. Atmospheric scavenging exhaust

    NASA Technical Reports Server (NTRS)

    Fenton, D. L.; Purcell, R. Y.

    1977-01-01

    Solid propellant rocket exhaust was directly utilized to ascertain raindrop scavenging rates for hydrogen chloride. The airborne HCl concentration varied from 0.2 to 10.0 ppm and the raindrop sizes tested included 0.55 mm, 1.1 mm, and 3.0 mm. Two chambers were used to conduct the experiments. A large, rigid walled, spherical chamber stored the exhaust constituents while the smaller chamber housing all the experiments was charged as required with rocket exhaust HCl. Surface uptake experiments demonstrated an HCl concentration dependence for distilled water. Sea water and brackish water HCl uptake was below the detection limit of the chlorine-ion analysis technique employed. Plant life HCl uptake experiments were limited to corn and soybeans. Plant age effectively correlated the HCl uptake data. Metallic corrosion was not significant for single 20 minute exposures to the exhaust HCl under varying relative humidity.

  6. Influence of compressive strength and applied force in concrete on particles exposure concentrations during cutting processes.

    PubMed

    Soo, Jhy-Charm; Tsai, Perng-Jy; Chen, Ching-Hwa; Chen, Mei-Ru; Hsu, Hsin-I; Wu, Trong-Neng

    2011-08-01

    The objective of this research was to identify the influence of applied force (AF) and the compressive strength (CS) of concrete on particle exposure concentrations during concrete cutting processes. Five cutting conditions were selected with AF varied between 9.8 and 49 N and CS varied between 2500 and 6000 psi. For each selected cutting condition, the measured total dust concentrations (C(tot)) were used to further determine the corresponding three health-related exposure concentrations of the inhalable (C(inh)), thoracic (C(thor)), and respirable fraction (C(res)). Results show that particle size distribution was consistently in a bimodal form under all selected cutting conditions. An increase in CS resulted in an increase in coarse particle generations leading to an increase in the four measured particle exposure levels. An increase in AF resulted in an increase in exposure concentrations with a higher fraction of fine particles (i.e., C(tho) and C(res)) However, for particle exposure concentrations with a higher fraction of coarse particles (i.e., C(tot) and C(inh)), an increase in AF resulted in an initial increase, followed by a decrease in concentration. Finally, the above inferences were further confirmed through the use of fixed-effect models to determine the influence of both CS and AF on the four exposure concentrations. These results provide a reference for industries to initiate appropriate control strategies to reduce the exposure levels encountered by workers. PMID:21621248

  7. Dietary modulation of the effects of exposure to 56Fe particles

    NASA Astrophysics Data System (ADS)

    Rabin, B. M.; Joseph, J. A.; Shukitt-Hale, B.; Carey, A. N.

    On exploratory missions to other planets, astronauts will be exposed to galactic cosmic rays composed of protons and heavy particles, such as 56Fe. Long-term exposure to these particles can cause cancer. However, there are significant uncertainties in the risk estimates for the probability of developing heavy particle-induced cancer, and in the amount of shielding needed to provide an adequate level of radiation protection. The results of this preliminary study, using a ground-based model for exposure to cosmic rays, show reduced tumorigenesis in rats maintained on diets containing blueberry or strawberry extract prior to exposure to 56Fe particles. Because the study was not initially designed to evaluate tumorigenesis following exposure to 56Fe particles, additional research is needed to evaluate the effectiveness of strawberry and blueberry supplementation. However, the preliminary results presented in this study suggest that diets containing antioxidant phytochemicals can provide additional radiation protection on interplanetary voyages.

  8. FINE PARTICLE EXPOSURE IS ASSOCIATED WITH ALTERED VENTRICULAR REPOLARIZATION

    EPA Science Inventory

    Exposure to fine airborne particulate matter (PM2.5) has previously been associated with cardiac events, especially in older people with cardiovascular disease and in diabetics. This study examined the cardiac effects of short-term exposures to ambient PM2.5 in a prospective pane...

  9. Evaluation of the reactivity of exhaust from various biodiesel blends as a measure of possible oxidative effects: A concern for human exposure.

    PubMed

    Adenuga, Adeniyi A; Wright, Monica E; Atkinson, Dean B

    2016-03-01

    Diesel exhaust particles (DEP) are a major constituent of ambient air pollution and are associated with various adverse health effects, posing a major safety and public health concern in ambient and occupational environments. The effects of DEP from various biodiesel blends on biological systems was investigated using glutathione (GSH) as a marker of possible oxidative effects, based on the decrease in the concentration of GSH at physiological pH. The fluorophoric agent 2,3-naphthalenedicarboxaldehyde (NDA) was used as a selective probe of GSH in the presence of any likely interferents via fluorescence detection. Three different polar solvents (acetonitrile, methanol and water) were used to extract DEP generated during the combustion of different biodiesel blends (5%-99%). Oxidation of GSH to the disulfide (GSSG) was confirmed using electrospray ionization mass spectrometry. A decrease in the concentration of GSH was observed in the presence of DEP extracts from all of the biodiesel blends studied, with reaction rates that depend on the biodiesel blend. Interestingly the reactivity peaked at 50% biodiesel (B50) rather than decreasing monotonically with increased biodiesel content, as was expected. Organic solvent DEP extracts showed wider variations in reactivity with GSH, with methanol extracts giving the largest decrease in GSH concentrations. This may imply a more organic nature of the oxidants in the biodiesel exhaust. It is therefore important to consider ways of reducing concentrations of organic components in biodiesel exhaust that can cause different toxic activity before any blend is offered as a preferred alternative to petroleum diesel fuel. PMID:26774305

  10. Aconitine "challenge" test reveals a single whole-body exposure to diesel exhaust increases cardiac arrhythmia risk in hypertensive rats

    EPA Science Inventory

    Epidemiological studies demonstrate a significant association between cardiac electrical dysfunction, arrhythmias and air pollution exposure. Sensitivity to aconitine-induced arrhythmia has been used repeatedly to examine the factors that increase the risk of such cardiac electri...

  11. Application of Novel Method to Measure Endogenous VOCs in Exhaled Breath Condensate Before and After Exposure to Diesel Exhaust

    EPA Science Inventory

    Polar volatile organic compounds (PVOCs) such as aldehydes, ketones, and alcohols are byproducts of normal human metabolism and are present in exhaled breath and blood. Environmental exposures, individual activities, and disease states can perturb normal metabolic processes and ...

  12. Commuter exposure to ultrafine particles in different urban locations, transportation modes and routes

    NASA Astrophysics Data System (ADS)

    Ragettli, Martina S.; Corradi, Elisabetta; Braun-Fahrländer, Charlotte; Schindler, Christian; de Nazelle, Audrey; Jerrett, Michael; Ducret-Stich, Regina E.; Künzli, Nino; Phuleria, Harish C.

    2013-10-01

    A better understanding of ultrafine particle (UFP) exposure in different urban transport microenvironments is important for epidemiological exposure assessments and for policy making. Three sub-studies were performed to characterize personal exposure to UFP concentration and average particle size distribution diameters in frequently traveled commuter microenvironments in the city of Basel, Switzerland. First, the spatial variation of sidewalk UFP exposures within urban areas and transport-specific microenvironments was explored. Second, exposure to UFP concentration and average particle size were quantified for five modes of transportation (walking, bicycle, bus, tram, car) during different times of the day and week, along the same route. Finally, the contribution of bicycle commuting along two different routes (along main roads, away from main roads) to total daily exposures was assessed by 24-h personal measurements. In general, smaller average particle sizes and higher UFP levels were measured at places and for travel modes in close proximity to traffic. Average trip UFP concentrations were higher in car (31,784 particles cm-³) and on bicycle (22,660 particles cm-³) compared to walking (19,481 particles cm-³) and public transportation (14,055-18,818 particles cm-³). Concentrations were highest for all travel modes during weekday morning rush hours, compared to other time periods. UFP concentration was lowest in bus, regardless of time period. Bicycle travel along main streets between home and work place (24 min on average) contributed 21% and 5% to total daily UFP exposure in winter and summer, respectively. Contribution of bicycle commutes to total daily UFP exposure could be reduced by half if main roads are avoided. Our results show the importance of considering commuter behavior and route choice in exposure assessment studies.

  13. Acute Effects of Exposure to (56)Fe and (16)O Particles on Learning and Memory.

    PubMed

    Rabin, Bernard M; Poulose, Shibu M; Carrihill-Knoll, Kirsty L; Ramirez, Francisco; Bielinski, Donna F; Heroux, Nicholas; Shukitt-Hale, Barbara

    2015-08-01

    Although it has been shown that exposure to HZE particles disrupts cognitive performance when tested 2-4 weeks after irradiation, it has not been determined whether exposure to HZE particles acutely affects cognitive performance, i.e., within 4-48 h after exposure. The current experiments were designed to determine the acute effects of exposure to HZE particles ((16)O and (56)Fe) on cognitive performance and whether exposure to HZE particles affected learning or memory, as well as to understand the relationship between acute changes in the levels of NOX2 (a measure of oxidative stress) and COX2 (a measure of neuroinflammation) in specific brain regions and cognitive performance. The results of these studies indicate that the acute effects of radiation exposure on cognitive performance are on memory, not learning. Further, the acute effects of exposure to HZE particles on oxidative stress and neuroinflammation and their relationship to cognitive performance indicate that, although the effects of exposure to both (56)Fe and (16)O are widespread, only changes in specific regions of the brain may be related to changes in cognitive function. PMID:26207687

  14. Diesel exhaust particle-treated human bronchial epithelial cells upregulate Jagged-1 and OX40L in myeloid dendritic cells via TSLP1

    PubMed Central

    Bleck, Bertram; Tse, Doris B.; Gordon, Terry; Ahsan, Mohammad R.; Reibman, Joan

    2014-01-01

    Ambient particulate matter (PM), including diesel exhaust particles (DEP), promote the development of allergic disorders. Diesel exhaust particles increase oxidative stress and influence human bronchial epithelial cell (HBEC)-dendritic cell (DC) interactions via cytokines including thymic stromal lymphopoietin (TSLP). Upregulation of TSLP results in Th2 responses. Using primary culture human bronchial epithelial cells (pHBEC) and human myeloid DC co-cultures we now show that DEP upregulation of Th2 responses occurred via HBEC-dependent mechanisms that resulted from oxidative stress. Moreover, DEP-treated HBEC and ambient-PM-treated HBEC upregulated OX40L and the Notch ligand Jagged-1 mRNA and expression on mDC. Upregulation of OX40L as well as Jagged-1 on mDC required HBEC and did not occur in the presence of n-acetylcysteine (NAC). Furthermore, OX40L and Jagged-1 upregulation was inhibited when HBEC expression of TSLP was silenced. Thus DEP-treatment of HBEC targeted two distinct pathways in mDC that were downstream of TSLP expression. Upregulation of OX40L and Jagged-1 by mDC resulted in mDC driven Th2 responses. These studies expand our understanding of the mechanism by which ambient pollutants alter mucosal immunity and promote disorders such as asthma. PMID:20974985

  15. Comparison of two expert-based assessments of diesel exhaust exposure in a case-control study: Programmable decision rules versus expert review of individual jobs

    PubMed Central

    Pronk, Anjoeka; Stewart, Patricia A.; Coble, Joseph B.; Katki, Hormuzd A.; Wheeler, David C.; Colt, Joanne S.; Baris, Dalsu; Schwenn, Molly; Karagas, Margaret R.; Johnson, Alison; Waddell, Richard; Verrill, Castine; Cherala, Sai; Silverman, Debra T.; Friesen, Melissa C.

    2012-01-01

    Objectives Professional judgment is necessary to assess occupational exposure in population-based case-control studies; however, the assessments lack transparency and are time-consuming to perform. To improve transparency and efficiency, we systematically applied decision rules to the questionnaire responses to assess diesel exhaust exposure in the New England Bladder Cancer Study, a population-based case-control study. Methods 2,631 participants reported 14,983 jobs; 2,749 jobs were administered questionnaires (‘modules’) with diesel-relevant questions. We applied decision rules to assign exposure metrics based solely on the occupational history responses (OH estimates) and based on the module responses (module estimates); we combined the separate OH and module estimates (OH/module estimates). Each job was also reviewed one at a time to assign exposure (one-by-one review estimates). We evaluated the agreement between the OH, OH/module, and one-by-one review estimates. Results The proportion of exposed jobs was 20–25% for all jobs, depending on approach, and 54–60% for jobs with diesel-relevant modules. The OH/module and one-by-one review had moderately high agreement for all jobs (κw=0.68–0.81) and for jobs with diesel-relevant modules (κw=0.62–0.78) for the probability, intensity, and frequency metrics. For exposed subjects, the Spearman correlation statistic was 0.72 between the cumulative OH/module and one-by-one review estimates. Conclusions The agreement seen here may represent an upper level of agreement because the algorithm and one-by-one review estimates were not fully independent. This study shows that applying decision-based rules can reproduce a one-by-one review, increase transparency and efficiency, and provide a mechanism to replicate exposure decisions in other studies. PMID:22843440

  16. Combusting vegetable oils in diesel engines: the impact of unsaturated fatty acids on particle emissions and mutagenic effects of the exhaust.

    PubMed

    Bünger, Jürgen; Bünger, Jörn F; Krahl, Jürgen; Munack, Axel; Schröder, Olaf; Brüning, Thomas; Hallier, Ernst; Westphal, Götz A

    2016-06-01

    High particle emissions and strong mutagenic effects were observed after combustion of vegetable oil in diesel engines. This study tested the hypothesis that these results are affected by the amount of unsaturated or polyunsaturated fatty acids of vegetable oils. Four different vegetable oils (coconut oil, CO; linseed oil, LO; palm tree oil, PO; and rapeseed oil, RO) and common diesel fuel (DF) were combusted in a heavy-duty diesel engine. The exhausts were investigated for particle emissions and mutagenic effects in direct comparison with emissions of DF. The engine was operated using the European Stationary Cycle. Particle masses were measured gravimetrically while mutagenicity was determined using the bacterial reverse mutation assay with tester strains TA98 and TA100. Combustion of LO caused the largest amount of total particulate matter (TPM). In comparison with DF, it particularly raised the soluble organic fraction (SOF). RO presented second highest TPM and SOF, followed by CO and PO, which were scarcely above DF. RO revealed the highest number of mutations of the vegetable oils closely followed by LO. PO was less mutagenic, but still induced stronger effects than DF. While TPM and SOF were strongly correlated with the content of polyunsaturated fatty acids in the vegetable oils, mutagenicity had a significant correlation with the amount of total unsaturated fatty acids. This study supports the hypothesis that numbers of double bounds in unsaturated fatty acids of vegetable oils combusted in diesel engines influence the amount of emitted particles and the mutagenicity of the exhaust. Further investigations have to elucidate the causal relationship. PMID:26126632

  17. COMPARISON OF THE PARTICLE SIZE DISTRIBUTION OF HEAVY-DUTY DIESEL EXHAUST USING A DILUTION TAIL-PIPE SAMPLER AND IN-PLUME SAMPLER DURING ON-ROAD OPERATION

    EPA Science Inventory

    The paper compares the particle size distribution of heavy-duty diesel exhaust using a dilution tail-pipe sampler and an in-plume sampler during on-road operation. EPA's On-road Diesel Emissions Characterization Facility, modified to incorporate particle measurement instrumentat...

  18. Effects of biodiesel, engine load and diesel particulate filter on nonvolatile particle number size distributions in heavy-duty diesel engine exhaust.

    PubMed

    Young, Li-Hao; Liou, Yi-Jyun; Cheng, Man-Ting; Lu, Jau-Huai; Yang, Hsi-Hsien; Tsai, Ying I; Wang, Lin-Chi; Chen, Chung-Bang; Lai, Jim-Shoung

    2012-01-15

    Diesel engine exhaust contains large numbers of submicrometer particles that degrade air quality and human health. This study examines the number emission characteristics of 10-1000 nm nonvolatile particles from a heavy-duty diesel engine, operating with various waste cooking oil biodiesel blends (B2, B10 and B20), engine loads (0%, 25%, 50% and 75%) and a diesel oxidation catalyst plus diesel particulate filter (DOC+DPF) under steady modes. For a given load, the total particle number concentrations (N(TOT)) decrease slightly, while the mode diameters show negligible changes with increasing biodiesel blends. For a given biodiesel blend, both the N(TOT) and mode diameters increase modestly with increasing load of above 25%. The N(TOT) at idle are highest and their size distributions are strongly affected by condensation and possible nucleation of semivolatile materials. Nonvolatile cores of diameters less than 16 nm are only observed at idle mode. The DOC+DPF shows remarkable filtration efficiency for both the core and soot particles, irrespective of the biodiesel blend and engine load under study. The N(TOT) post the DOC+DPF are comparable to typical ambient levels of ≈ 10(4)cm(-3). This implies that, without concurrent reductions of semivolatile materials, the formation of semivolatile nucleation mode particles post the after treatment is highly favored. PMID:22119306

  19. Exhaust Fine Particle and Nitrogen Oxide Emissions from Individual Heavy-Duty Trucks at the Port of Oakland

    NASA Astrophysics Data System (ADS)

    Dallmann, T. R.; Harley, R. A.; Kirchstetter, T.

    2010-12-01

    Heavy-duty (HD) diesel trucks are a source of nitrogen oxide (NOx) emissions as well as primary fine particulate matter (PM2.5) that includes black carbon (BC) as a major component. Heavy-duty trucks contribute significantly to elevated levels of diesel particulate matter found near highways and in communities surrounding major freight-handling facilities. To reduce the air quality impact of diesel engine emissions, the California Air Resources Board has adopted new rules requiring the retrofit or replacement of in-use HD trucks. These rules take effect during 2010 at ports and railyards, and apply to all trucks operating in California by 2014. This study involves on-road measurements of PM2.5, BC, and NOx emission factor distributions from individual HD trucks driving into the Port of Oakland in the San Francisco Bay area. Measurements of exhaust plumes from individual trucks were made using a mobile laboratory equipped with fast time response (1 Hz) PM2.5, BC, NOx, and carbon dioxide (CO2) sensors. The mobile laboratory was stationed on an overpass above an arterial roadway that connects the Port to a nearby highway (I-880). The air sampling inlet was thereby located above the vertical exhaust pipes of HD diesel trucks passing by on the arterial roadway below. Fuel-specific PM2.5, BC, and NOx emission factors for individual trucks were calculated using a carbon balance method in which concentrations of these species in an exhaust plume are normalized to CO2 concentrations. Initial field sampling was conducted in November, 2009 prior to the implementation of new emission rules. Additional emission measurements were made at the same location during June 2010 and emission factor distributions and averages will be compared.

  20. Part 3. Assessment of genotoxicity and oxidative damage in rats after chronic exposure to new-technology diesel exhaust in the ACES bioassay.

    PubMed

    Hallberg, Lance M; Ward, Jonathan B; Hernandez, Caterina; Ameredes, Bill T; Wickliffe, Jeffrey K

    2015-01-01

    In 2001, the U.S. Environmental Protection Agency (EPA*) and the California Air Resources Board (CARB) adopted new standards for diesel fuel and emissions from heavy-duty diesel engines. By 2007, diesel engines were required to meet these new standards for particulate matter (PM), with other standards to follow. Through a combination of advanced compression-ignition engine technology, development of exhaust aftertreatment systems, and reformulated fuels, stringent standards were introduced. Before the 2007 standards were put in place by the EPA, human health effects linked to diesel exhaust (DE) exposure had been associated with diesel-fuel solvent and combustion components. In earlier research, diesel engine exhaust components were, in turn, linked to increased mutagenicity in cultures of Salmonella typhimurium and mammalian cells (Tokiwa and Ohnishi 1986). In addition, DE was shown to increase both the incidence of tumors and the induction of 8-hydroxy-deoxyguanosine (8-OHdG) adducts in rodents (Ichinose et al. 1997) and total DNA adducts in rats (Bond et al. 1990). Furthermore, DE is composed of a complex mixture of polycyclic aromatic hydrocarbons (PAHs) and particulates. One such PAH, 3-nitrobenzanthrone (3-NBA), is also found in urban air. 3-NBA has been observed to induce micronucleus formation in the DNA of human hepatoma cells (Lamy et al. 2004). The current study is part of the Advanced Collaborative Emissions Study (ACES), a multidisciplinary program carried out by the Health Effects Institute and the Coordinating Research Council. Its purpose was to determine whether recent improvements in the engineering of heavy-duty diesel engines reduce the toxicity associated with exposure to DE components. To this end, we evaluated potential genotoxicity and induction of oxidative stress in bioassays of serum and tissues from Wistar Han rats chronically exposed--for up to 24 months--to DE from a 2007-compliant diesel engine (new-technology diesel exhaust, or NTDE

  1. Dermal absorption of amorphous nanosilica particles after topical exposure for three days.

    PubMed

    Hirai, T; Yoshikawa, T; Nabeshi, H; Yoshida, T; Akase, T; Yoshioka, Y; Itoh, N; Tsutsumi, Y

    2012-08-01

    The skin penetration and cellular localization of well-dispersed amorphous nanosilica particles (nSPs) with a diameter of 70 nm was analyzed in mice. Our results suggest that after topical exposure for three days the particles penetrate the skin barrier and are transported to the lymph nodes. These findings underscore the need to examine biological effects following dermal exposure to nSPs for the development of safer use of nSPs. PMID:22957443

  2. Protective Effects of N-Acetyl Cysteine against Diesel Exhaust Particles-Induced Intracellular ROS Generates Pro-Inflammatory Cytokines to Mediate the Vascular Permeability of Capillary-Like Endothelial Tubes

    PubMed Central

    Tseng, Chia-Yi; Chang, Jing-Fen; Wang, Jhih-Syuan; Chang, Yu-Jung; Gordon, Marion K.; Chao, Ming-Wei

    2015-01-01

    Exposure to diesel exhaust particles (DEP) is associated with pulmonary and cardiovascular diseases. Previous studies using in vitro endothelial tubes as a simplified model of capillaries have found that DEP-induced ROS increase vascular permeability with rearrangement or internalization of adherens junctional VE-cadherin away from the plasma membrane. This allows DEPs to penetrate into the cell and capillary lumen. In addition, pro-inflammatory cytokines are up-regulated and mediate vascular permeability in response to DEP. However, the mechanisms through which these DEP-induced pro-inflammatory cytokines increase vascular permeability remain unknown. Hence, we examined the ability of DEP to induce permeability of human umbilical vein endothelial cell tube cells to investigate these mechanisms. Furthermore, supplementation with NAC reduces ROS production following exposure to DEP. HUVEC tube cells contributed to a pro-inflammatory response to DEP-induced intracellular ROS generation. Endothelial oxidative stress induced the release of TNF-α and IL-6 from tube cells, subsequently stimulating the secretion of VEGF-A independent of HO-1. Our data suggests that DEP-induced intracellular ROS and release of the pro-inflammatory cytokines TNF- α and IL-6, which would contribute to VEGF-A secretion and disrupt cell-cell borders and increase vasculature permeability. Addition of NAC suppresses DEP-induced ROS efficiently and reduces subsequent damages by increasing endogenous glutathione. PMID:26148005

  3. Operant responding following exposure to HZE particles and its relationship to particle energy and LET

    Technology Transfer Automated Retrieval System (TEKTRAN)

    On exploratory class missions astronauts will be exposed to range of heavy particles which differ in terms of particle energy and particle linear energy transfer. The present experiments were designed to evaluate how these physical characteristics of different particles affect cognitive performance...

  4. Biomarker as a Research Tool in Linking Exposure to Air Particles and Respiratory Health

    PubMed Central

    2015-01-01

    Some of the environmental toxicants from air pollution include particulate matter (PM10), fine particulate matter (PM2.5), and ultrafine particles (UFP). Both short- and long-term exposure could result in various degrees of respiratory health outcomes among exposed persons, which rely on the individuals' health status. Methods. In this paper, we highlight a review of the studies that have used biomarkers to understand the association between air particles exposure and the development of respiratory problems resulting from the damage in the respiratory system. Data from previous epidemiological studies relevant to the application of biomarkers in respiratory system damage reported from exposure to air particles are also summarized. Results. Based on these analyses, the findings agree with the hypothesis that biomarkers are relevant in linking harmful air particles concentrations to increased respiratory health effects. Biomarkers are used in epidemiological studies to provide an understanding of the mechanisms that follow airborne particles exposure in the airway. However, application of biomarkers in epidemiological studies of health effects caused by air particles in both environmental and occupational health is inchoate. Conclusion. Biomarkers unravel the complexity of the connection between exposure to air particles and respiratory health. PMID:25984536

  5. On-bicycle exposure to particulate air pollution: Particle number, black carbon, PM2.5, and particle size

    NASA Astrophysics Data System (ADS)

    Hankey, Steve; Marshall, Julian D.

    2015-12-01

    Inhalation of air pollution during transport is an important exposure pathway, especially for certain modes of travel and types of particles. We measured concentrations of particulate air pollution (particle number [PN], black carbon [BC], fine particles [PM2.5], particle size) using a mobile, bicycle-based monitoring platform during morning and afternoon rush-hour to explore patterns of exposure while cycling (34 days between August 14 and October 16, 2012 in Minneapolis, MN). Measurements were geo-located at 1 ​s intervals along 3 prescribed monitoring routes totaling 85 h (1426 km) of monitoring. Mean morning [afternoon] on-road concentrations were 32,500 [16,600] pt cm-3, 2.5 [0.7] μg m-3 BC, 8.7 [8.3] μg m-3 PM2.5, and 42 [39] nm particle diameter. Concentrations were correlated with street functional class and declined within small distances from a major road (e.g., for PN and BC, mean concentration decreased ∼20% by moving 1 block away from major roads to adjacent local roads). We estimate the share of on-bicycle exposure attributable to near-traffic emissions (vs. regional pollution) is ∼50% for PN and BC; ∼25% for PM2.5. Regression models of instantaneous traffic volumes, derived from on-bicycle video recordings of nearby traffic, quantify the increase in particle-concentrations associated with each passing vehicle; for example, trucks were associated with acute, high concentration exposure events (average concentration-increase per truck: 31,000 pt cm-3, 1.0 μg m-3 PM2.5, 1.6 μg m-3 BC). Our findings could be used to inform design of low-exposure bicycle networks in urban areas.

  6. Reducing silica and dust exposures in construction during use of powered concrete-cutting hand tools: efficacy of local exhaust ventilation on hammer drills.

    PubMed

    Shepherd, S; Woskie, S R; Holcroft, C; Ellenbecker, M

    2009-01-01

    Concrete cutting in construction is a major source of exposure to respirable crystalline silica. To reduce exposures, local exhaust ventilation (LEV) may be integrated into the hand tools used in concrete cutting. Volunteers from the New England Laborers Training Center participated in a field study focused on the use of LEV on concrete-cutting hammer drills. A randomized block design field experiment employing four workers measured the efficacy of four hood-vacuum source combinations compared with no LEV in reducing dust and silica exposures. Using four-stage personal cascade impactors (Marple 294) to measure dust exposure, a total of 18 personal samples were collected. Reductions of over 80% in all three biologically relevant size fractions of dust (inhalable, thoracic, and respirable) were obtained by using any combination of hood and vacuum source. This study found that respirable dust concentrations were reduced from 3.77 mg/m(3) to a range of 0.242 to 0.370 mg/m(3); thoracic dust concentrations from 12.5 mg/m(3) to a range of 0.774 to 1.23 mg/m(3); and inhalable dust concentration from 47.2 mg/m(3) to a range of 2.13 to 6.09 mg/m(3). Silica concentrations were reduced from 0.308 mg/m(3) to a range of 0.006 to 0.028 mg/m(3) in the respirable size fraction, from 0.821 mg/m(3) to a range of 0.043 to 0.090 mg/m(3) in the thoracic size fraction, and from 2.71 mg/m(3) to a range of 0.124 to 0.403 mg/m(3) in the inhalable size fraction. Reductions in dust concentrations while using the four LEV systems were not statistically significantly different from each other. PMID:19005968

  7. TOTAL HUMAN EXPOSURE MODEL (THEM) FOR RESPIRABLE SUSPENDED PARTICLES (RSP)

    EPA Science Inventory

    A Total Human Exposure Model (THEM) has been developed that calculates 24-hour profiles using real human activity patterns and indoor air models derived from actual measurements of pollutants. HEM was designed for implementation on personal computers. urrently, the model uses the...

  8. CONTROLLED EXPOSURES OF HEALTHY AND ASTHMATIC VOLUNTEERS TO CONCENTRATED AMBIENT PARTICLES IN METROPOLITAN LOS ANGELES

    EPA Science Inventory

    Investigators expect to use a Harvard ambient particle concentrator to assess the effects of exposure to concentrated ambient particles (CAPs) on healthy and asthmatic people.  12 healthy individuals and 12 individuals with mild asthma will be exposed to either filtere...

  9. PERSONAL EXPOSURE TO FINE PARTICLE POLYCYCLIC AROMATIC HYDROCARBONS: OUTDOOR SOURCE TRACERS

    EPA Science Inventory


    The most carcinogenic and toxic polycyclic aromatic hydrocarbons (PAH) are the 4-5 ring PAH found preferentially adsorbed to the fine particles (<2.54u in urban ambient air and personal air. Personal exposure to the carcinogenic particle bound PAH is also highly correlated ...

  10. Neuronal stress following exposure to 56Fe particles and the effects of antioxidant-rich diets

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Exposing young rats to particles of high energy and charge (HZE particles), a ground-based model for exposure to cosmic rays, enhances indices of oxidative stress and inflammation and disrupts the functioning of neuronal communication in critical regions of the brain. These changes in neuronal funct...

  11. UP-REGULATION OF TISSUE FACTOR IN HUMAN PULMONARY ARTERY ENDOTHELIAL CELLS AFTER ULTRAFINE PARTICLE EXPOSURE

    EPA Science Inventory

    Background: Epidemiology studies have linked exposure to pollutant particles to

    increased cardiovascular mortality and morbidity, but the mechanisms remain unknown.

    Objectives: We tested the hypothesis that the ultrafine fraction of ambient pollutant

    particle...

  12. Neuronal stress following exposure to 56Fe particles and the effects of antioxidant-rich diets

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Exposing young rats to particles of high energy and charge (HZE particles), a ground-based model for exposure to cosmic rays, enhances indices of oxidative stress and inflammation and disrupts the functioning of neuronal communication in critical regions of the brain, similar to those seen in aging....

  13. EXPOSURE RELATIONSHIP OF PERSONAL EXPOSURE OF HIGH-RISK SUBPOPULATIONS TO AMBIENT CONCENTRATIONS OF FINE PARTICLES.

    EPA Science Inventory

    An association has been demonstrated between ambient particulate matter (PM 2.5 and PM 10) concentrations and human morbidity/mortality. However, little is known regarding the most important sources of PM exposure, interpersonal and intrapersonal variability in exposure, and the...

  14. Part 3. Assessment of genotoxicity and oxidative stress after exposure to diesel exhaust from U.S. 2007-compliant diesel engines: report on 1- and 3-month exposures in the ACES bioassay.

    PubMed

    Hallberg, L M; Ward, J B; Hernandez, C; Ameredes, B T; Wickliffe, J K

    2012-09-01

    Human health hazards due to diesel exhaust (DE*) exposure have been associated with both solvent and combustion components. In the past, diesel engine exhaust components have been linked to increased mutagenicity in cultures of Salmonella typhimurium and mammalian cells (Tokiwa and Ohnishi 1986). In addition, DE has been shown to increase both the incidence of tumors and the induction of 8-hydroxy-deoxyguanosine adducts (8-OHdG) in ICR mice (Ichinose et al. 1997). Furthermore, DE is composed of a complex mixture of polycyclic aromatic hydrocarbons (PAHs) and particulates. One such PAH, 3-nitrobenzanthrone (3-NBA), has been identified in DE and found in urban air. 3-NBA has been observed to induce micronucleus formation in DNA of human hepatoma cells (Lamy et al. 2004). The purpose of the current research, which is part of the Advanced Collaborative Emissions Study (ACES), a multidisciplinary program being carried out by the Health Effects Institute and the Coordinating Research Council, is to determine whether improvements in the engineering of heavy-duty diesel engines reduce the oxidative stress and genotoxic risk associated with exposure to DE components. To this end, the genotoxicity and oxidative stress of DE from an improved diesel engine was evaluated in bioassays of tissues from Wistar Han rats and C57BL/6 mice exposed to DE. Genotoxicity was measured as strand breaks using an alkaline-modified comet assay. To correlate possible DNA damage found by the comet assay, measurement of DNA-adduct formation was evaluated by a competitive enzyme-linked immunosorbent assay (ELISA) to determine the levels of free 8-OHdG found in the serum of the animals exposed to DE. 8-OHdG is a specific modified base indicating an oxidative type of DNA damage to DNA nucleotides. In addition, a thiobarbituric acid reactive substances (TBARS) assay was used to assess oxidative stress and damage in the form of lipid peroxidation in the hippocampus region of the brains of DE

  15. Diet as a factor in behavioral radiation protection following exposure to heavy particles

    NASA Technical Reports Server (NTRS)

    Rabin, Bernard M.; Shukitt-Hale, Barbara; Joseph, James; Todd, Paul

    2005-01-01

    Major risks associated with radiation exposures on deep space missions include carcinogenesis due to heavy-particle exposure of cancer-prone tissues and performance decrements due to neurological damage produced by heavy particles. Because exposure to heavy particles can cause oxidative stress, it is possible that antioxidants can be used to mitigate these risks (and possibly some health risks of microgravity). To assess the capacity of antioxidant diets to mitigate the effects of exposure to heavy particles, rats were maintained on antioxidant diets containing 2% blueberry or strawberry extract or a control diet for 8 weeks prior to exposure to 1.5 or 2.0 Gy of accelerated iron particles at Brookhaven National Laboratory. Following irradiation rats were tested on a series of behavioral tasks: amphetamine-induced taste aversion learning, operant responding and spatial learning and memory. The results indicated that the performance of the irradiated rats maintained on the antioxidant diets was, in general, significantly better than that of the control animals, although the effectiveness of the diets ameliorating the radiation-induced deterioration in performance varied as a function of both the specific diet and the specific endpoint. In addition, animals fed antioxidant diets prior to exposure showed reduced heavy particle-induced tumorigenesis one year after exposure compared to the animals fed the control diet. These results suggest that antioxidant diets have the potential to serve as part of a system designed to provide protection to astronauts against the effects of heavy particles on exploratory missions outside the magnetic field of the earth.

  16. Aryl hydrocarbon receptor-dependent up-regulation of the heterodimeric amino acid transporter LAT1 (SLC7A5)/CD98hc (SLC3A2) by diesel exhaust particle extract in human bronchial epithelial cells.

    PubMed

    Le Vee, Marc; Jouan, Elodie; Lecureur, Valérie; Fardel, Olivier

    2016-01-01

    The heterodimeric L-type amino acid transporter (LAT) 1/CD98hc is overexpressed in lung cancers with a poor prognosis factor. Factors that contribute to LAT1/CD98hc overexpression in lung cells remain however to be determined, but the implication of atmospheric pollution can be suspected. The present study was therefore designed to analyze the effects of diesel exhaust particle (DEP) extract (DEPe) on LAT1/CD98hc expression in bronchial epithelial BEAS-2B cells. Exposure to DEPe up-regulated LAT1 and CD98hc mRNA levels in a concentration-dependent manner, with DEPe EC50 values (around 0.2 μg/mL) relevant to environmental situations. DEPe concomitantly induced LAT1/CD98hc protein expression and LAT1-mediated leucine accumulation in BEAS-2B cells. Inhibition of the aryl hydrocarbon receptor (AhR) pathway through the use of a chemical AhR antagonist or the siRNA-mediated silencing of AhR expression was next found to prevent DEPe-mediated induction of LAT1/CD98hc, indicating that this regulation depends on AhR, known to be activated by major chemical DEP components like polycyclic aromatic hydrocarbons. DEPe exposure was finally shown to induce mRNA expression and activity of matrix metalloproteinase (MMP)-2 in BEAS-2B cells, in a CD98hc/focal adhesion kinase (FAK)/extracellular regulated kinase (ERK) manner, thus suggesting that DEPe-mediated induction of CD98hc triggers activation of the integrin/FAK/ERK signaling pathway known to be involved in MMP-2 regulation. Taken together, these data demonstrate that exposure to DEPe induces functional overexpression of the amino acid transporter LAT1/CD98hc in lung cells. Such a regulation may participate to pulmonary carcinogenic effects of DEPs, owing to the well-documented contribution of LAT1 and CD98hc to cancer development. PMID:26621329

  17. Protective effects of pulmonary epithelial lining fluid on oxidative stress and DNA single-strand breaks caused by ultrafine carbon black, ferrous sulphate and organic extract of diesel exhaust particles.

    PubMed

    Chuang, Hsiao-Chi; Cheng, Yi-Ling; Lei, Yu-Chen; Chang, Hui-Hsien; Cheng, Tsun-Jen

    2013-02-01

    Pulmonary epithelial lining fluid (ELF) is the first substance to make contact with inhaled particulate matter (PM) and interacts chemically with PM components. The objective of this study was to determine the role of ELF in oxidative stress, DNA damage and the production of proinflammatory cytokines following physicochemical exposure to PM. Ultrafine carbon black (ufCB, 15 nm; a model carbonaceous core), ferrous sulphate (FeSO(4); a model transition metal) and a diesel exhaust particle (DEP) extract (a model organic compound) were used to examine the acellular oxidative potential of synthetic ELF and non-ELF systems. We compared the effects of exposure to ufCB, FeSO(4) and DEP extract on human alveolar epithelial Type II (A549) cells to determine the levels of oxidative stress, DNA single-strand breaks and interleukin-8 (IL-8) production in ELF and non-ELF systems. The effects of ufCB and FeSO(4) on the acellular oxidative potential, cellular oxidative stress and DNA single-strand breakage were mitigated significantly by the addition of ELF, whereas there was no decrease following treatment with the DEP extract. There was no significant effect on IL-8 production following exposure to samples that were suspended in ELF/non-ELF systems. The results of the present study indicate that ELF plays an important role in the initial defence against PM in the pulmonary environment. Experimental components, such as ufCB and FeSO(4), induced the production of oxidative stress and led to DNA single-strand breaks, which were moderately prevented by the addition of ELF. These findings suggest that ELF plays a protective role against PM-driven oxidative stress and DNA damage. PMID:23261976

  18. Efficiency of automotive cabin air filters to reduce acute health effects of diesel exhaust in human subjects

    PubMed Central

    Rudell, B.; Wass, U.; Horstedt, P.; Levin, J. O.; Lindahl, R.; Rannug, U.; Sunesson, A. L.; Ostberg, Y.; Sandstrom, T.

    1999-01-01

    OBJECTIVES: To evaluate the efficiency of different automotive cabin air filters to prevent penetration of components of diesel exhaust and thereby reduce biomedical effects in human subjects. Filtered air and unfiltered diluted diesel exhaust (DDE) were used as negative and positive controls, respectively, and were compared with exposure to DDE filtered with four different filter systems. METHODS: 32 Healthy non- smoking subjects (age 21-53) participated in the study. Each subject was exposed six times for 1 hour in a specially designed exposure chamber: once to air, once to unfiltered DDE, and once to DDE filtered with the four different cabin air filters. Particle concentrations during exposure to unfiltered DDE were kept at 300 micrograms/m3. Two of the filters were particle filters. The other two were particle filters combined with active charcoal filters that might reduce certain gaseous components. Subjective symptoms were recorded and nasal airway lavage (NAL), acoustic rhinometry, and lung function measurements were performed. RESULTS: The two particle filters decreased the concentrations of diesel exhaust particles by about half, but did not reduce the intensity of symptoms induced by exhaust. The combination of active charcoal filters and a particle filter significantly reduced the symptoms and discomfort caused by the diesel exhaust. The most noticable differences in efficacy between the filters were found in the reduction of detection of an unpleasant smell from the diesel exhaust. In this respect even the two charcoal filter combinations differed significantly. The efficacy to reduce symptoms may depend on the abilities of the filters investigated to reduce certain hydrocarbons. No acute effects on NAL, rhinometry, and lung function variables were found. CONCLUSIONS: This study has shown that the use of active charcoal filters, and a particle filter, clearly reduced the intensity of symptoms induced by diesel exhaust. Complementary studies on vehicle

  19. Rat- and human-based risk estimates of lung cancer from occupational exposure to poorly-soluble particles: A quantitative evaluation

    NASA Astrophysics Data System (ADS)

    Kuempel, E. D.; Smith, R. J.; Dankovic, D. A.; Stayner, L. T.

    2009-02-01

    In risk assessment there is a need for quantitative evaluation of the capability of animal models to predict disease risks in humans. In this paper, we compare the rat- and human-based excess risk estimates for lung cancer from working lifetime exposures to inhaled poorly-soluble particles. The particles evaluated include those for which long-term dose-response data are available in both species, i.e., coal dust, carbon black, titanium dioxide, silica, and diesel exhaust particulate. The excess risk estimates derived from the rat data were generally lower than those derived from the human studies, and none of the rat- and human-based risk estimates were significantly different (all p-values>0.05). Residual uncertainty in whether the rat-based risk estimates would over- or under-predict the true excess risks of lung cancer from inhaled poorly-soluble particles in humans is due in part to the low power of the available human studies, limited particle size exposure data for humans, and ambiguity about the best animal models and extrapolation methods.

  20. Comparison of the effects of partial-or-whole-body exposures to 16O particles on cognitive performance in rats

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Studies using a ground-based system (NASA Space Radiation Laboratory) to study the effects of exposure to particles of high energy and charge (HZE particles) on cognitive performance have interchangeably used whole-body exposures or exposures restricted to the head of the subject. It is possible th...

  1. Effect of time-activity adjustment on exposure assessment for traffic-related ultrafine particles

    PubMed Central

    Lane, Kevin J; Levy, Jonathan I; Scammell, Madeleine Kangsen; Patton, Allison P; Durant, John L; Mwamburi, Mkaya; Zamore, Wig; Brugge, Doug

    2015-01-01

    Exposures to ultrafine particles (<100 nm, estimated as particle number concentration, PNC) differ from ambient concentrations because of the spatial and temporal variability of both PNC and people. Our goal was to evaluate the influence of time-activity adjustment on exposure assignment and associations with blood biomarkers for a near-highway population. A regression model based on mobile monitoring and spatial and temporal variables was used to generate hourly ambient residential PNC for a full year for a subset of participants (n=140) in the Community Assessment of Freeway Exposure and Health study. We modified the ambient estimates for each hour using personal estimates of hourly time spent in five micro-environments (inside home, outside home, at work, commuting, other) as well as particle infiltration. Time-activity adjusted (TAA)-PNC values differed from residential ambient annual average (RAA)-PNC, with lower exposures predicted for participants who spent more time away from home. Employment status and distance to highway had a differential effect on TAA-PNC. We found associations of RAA-PNC with high sensitivity C-reactive protein and Interleukin-6, although exposure-response functions were non-monotonic. TAA-PNC associations had larger effect estimates and linear exposure-response functions. Our findings suggest that time-activity adjustment improves exposure assessment for air pollutants that vary greatly in space and time. PMID:25827314

  2. Project SOLWIND: Space radiation exposure. [evaluation of particle fluxes

    NASA Technical Reports Server (NTRS)

    Stassinopoulos, E. G.

    1975-01-01

    A special orbital radiation study was conducted for the SOLWIND project to evaluate mission-encountered energetic particle fluxes. Magnetic field calculations were performed with a current field model, extrapolated to the tentative spacecraft launch epoch with linear time terms. Orbital flux integrations for circular flight paths were performed with the latest proton and electron environment models, using new improved computational methods. Temporal variations in the ambient electron environment are considered and partially accounted for. Estimates of average energetic solar proton fluences are given for a one year mission duration at selected integral energies ranging from E greater than 10 to E greater than 100 MeV; the predicted annual fluence is found to relate to the period of maximum solar activity during the next solar cycle. The results are presented in graphical and tabular form; they are analyzed, explained, and discussed.

  3. Influence of preexisting pulmonary emphysema on susceptibility of rats to inhaled diesel exhaust

    SciTech Connect

    Mauderly, J.L.; Bice, D.E.; Cheng, Y.S.; Gillett, N.A.; Griffith, W.C.; Henderson, R.F.; Pickrell, J.A.; Wolff, R.K. )

    1990-05-01

    The susceptibilities of normal rats and rats with preexisting pulmonary emphysema to chronically inhaled diesel exhaust were compared. Rats were exposed 7 h/day, 5 days/wk for 24 months to diesel exhaust at 3.5 mg soot/m3, or to clean air as controls. Emphysema was induced in one-half of the rats by intratracheal instillation of elastase 6 wk before exhaust exposure. Measurements included lung burdens of diesel soot, respiratory function, bronchoalveolar lavage, clearance of radiolabeled particles, pulmonary immune responses, lung collagen, excised lung weight and volume, histopathology, and mean linear intercept of terminal air spaces. Parameters indicated by analysis of variance to exhibit significant interactions between the influences of emphysema and exhaust were examined to determine if the effects were more than additive (indicating increased susceptibility). Although 14 of 63 parameters demonstrated emphysema-exhaust interactions, none indicated increased susceptibility. Less soot accumulated in lungs of emphysematous rats than in those of nonemphysematous rats, and the reduced accumulation had a sparing effect in the emphysematous rats. The results did not support the hypothesis that emphysematous lungs are more susceptible than are normal lungs to chronic exposure to high levels of diesel exhaust. The superimposition of effects of emphysema and exhaust, however, might still warrant special concern for heavy exposures of emphysematous subjects.

  4. Ultrafine particle emission of waste incinerators and comparison to the exposure of urban citizens.

    PubMed

    Buonanno, Giorgio; Morawska, Lidia

    2015-03-01

    On the basis of the growing interest on the impact of airborne particles on human exposure as well as the strong debate in Western countries on the emissions of waste incinerators, this work reviewed existing literature to: (i) show the emission factors of ultrafine particles (particles with a diameter less than 100 nm) of waste incinerators; and (ii) assess the contribution of waste incinerators in terms of ultrafine particles to exposure and dose of people living in the surrounding areas of the plants in order to estimate eventual risks. The review identified only a limited number of studies measuring ultrafine particle emissions, and in general they report low particle number concentrations at the stack (the median value was equal to 5.5×10(3) part cm(-3)), in most cases higher than the outdoor background value. The lowest emissions were achieved by utilization of the bag-house filter which has an overall number-based filtration efficiency higher than 99%. Referring to reference case, the corresponding emission factor is equal to 9.1×10(12) part min(-1), that is lower than one single high-duty vehicle. Since the higher particle number concentrations found in the most contributing microenvironments to the exposure (indoor home, transportation, urban outdoor), the contribution of the waste incinerators to the daily dose can be considered as negligible. PMID:24726660

  5. Pulmonary function in workers exposed to diesel exhausts: The effect of control measures

    SciTech Connect

    Ulfvarson, U.; Alexandersson, R.; Dahlqvist, M.; Ekholm, U.; Bergstroem, B. )

    1991-01-01

    To assess the protective effect of exhausts pipe filters or respirators on pulmonary function, 15 workers in a tunnel construction site, truck and loading machine drivers, rock workers, and others were studied. The total and respirable dust, combustible matter in respirable dust, carbon monoxide, nitrogen monoxide and nitrogen dioxide were measured for each subject during entire work shifts. The effect of the exposure on the lung function variables was measured by dynamic spirometry, carbon monoxide single breath technique, and nitrogen single breath wash-out. The exhaust pipe filtering had a protective effect, directly discernible in the drivers on vital capacity and FEV1.0 and for the whole group on FEV% and TLco. The dust respirators had no effect, probably because of the difficulties in correctly using personal protection under the circumstances in the tunnel. In the absence of a true exposure assessment, control measures for diesel exhausts can be tested by medical effect studies. Catalytic particle filters of diesel exhausts are one method of rendering the emissions less irritant, although they will not remove irritant gases. An indicator of diesel exhaust exposure should include the particle fraction of the diesel exhausts, but a discrimination between different sources of organic dust must be possible.

  6. Human bronchial epithelial cells exposed in vitro to diesel exhaust particles exhibit alterations in cell rheology and cytotoxicity associated with decrease in antioxidant defenses and imbalance in pro- and anti-apoptotic gene expression.

    PubMed

    Seriani, Robson; de Souza, Claudia Emanuele Carvalho; Krempel, Paloma Gava; Frias, Daniela Perroni; Matsuda, Monique; Correia, Aristides Tadeu; Ferreira, Márcia Zotti Justo; Alencar, Adriano Mesquita; Negri, Elnara Marcia; Saldiva, Paulo Hilário Nascimento; Mauad, Thais; Macchione, Mariangela

    2016-05-01

    Diesel exhaust particles (DEPs) from diesel engines produce adverse alterations in cells of the airways by activating intracellular signaling pathways and apoptotic gene overexpression, and also by influencing metabolism and cytoskeleton changes. This study used human bronchial epithelium cells (BEAS-2B) in culture and evaluates their exposure to DEPs (15ug/mL for 1 and 2 h) in order to determine changes to cell rheology (viscoelasticity) and gene expression of the enzymes involved in oxidative stress, apoptosis, and cytotoxicity. BEAS-2B cells exposed to DEPs were found to have a significant loss in stiffness, membrane stability, and mitochondrial activity. The genes involved in apoptosis [B cell lymphoma 2 (BCL-2 and caspase-3)] presented inversely proportional expressions (p = 0.05, p = 0.01, respectively), low expression of the genes involved in antioxidant responses [SOD1 (superoxide dismutase 1); SOD2 (superoxide dismutase 2), and GPx (glutathione peroxidase) (p = 0.01)], along with an increase in cytochrome P450, family 1, subfamily A, polypeptide 1 (CYP1A1) (p = 0.01). These results suggest that alterations in cell rheology and cytotoxicity could be associated with oxidative stress and imbalance between pro- and anti-apoptotic genes. PMID:26856867

  7. Biopersistence of nonfibrous mineral particles in the respiratory tracts of subjects following occupational exposure.

    PubMed Central

    Pairon, J C; Billon-Galland, M A; Iwatsubo, Y; Bernstein, M; Gaudichet, A; Bignon, J; Brochard, P

    1994-01-01

    Transmission electron microscopy analysis (TEMA) was used to analyze the bronchoalveolar lavage fluid (BALF) of 262 subjects occupationally exposed (OE) to nonfibrous mineral particles (NFMP) and 42 controls not occupationally exposed to mineral dusts. OE subjects were divided into three groups according to the lapse of time since last exposure: < or = 1 year and < 10 years (E2), > or = 10 years (E3). The total BALF mineral particle concentration was significantly higher in OE patients than in controls and was closely related to the time lapse since last exposure to NFMP (median values for OE, 7.7 x 10(5) particles/ml; E1, 9 x 10(5) particles/ml; E2, 5 x 10(5) particles/ml; E3, 4.3 x 10(5) particles/ml; controls, 2 x 10(5) particles/ml). No statistical difference was observed for age and smoking habits between OE and control subjects. Concentrations of crystalline silica and metals (exogenous iron, aluminum, metallic alloys and other metals) were significantly higher in OE subjects than in controls, and even though these mineral concentrations decreased with increasing time since last occupational exposure, they still remained higher in the E3 group than in controls. Crystalline silica and metals were thus identified as biopersistent NFMP in the human lung using BALF ATEM method. This method is a useful tool in assessing occupational exposure to NFMP, even when a long period has elapsed since last exposure, and may be used in studying etiology of some respiratory diseases. PMID:7882949

  8. LIVE CELL IMAGING OF THE OXIDATIVE EFFECTS OF EXPOSURE TO AN ORGANIC PM COMPONENT

    EPA Science Inventory

    RATIONALE. Exposure to ambient particulate matter (PM) has been associated with adverse health effects, including inflammatory responses in the lung. Diesel exhaust particles (DEP) are a ubiquitous contributor of the fine and ultrafine PM burden in ambient air. Toxicological stud...

  9. Exposure To An Organic PM Component Induces Inflammatory And Adaptive Gene Expression Through Mitochondrial Oxidative Stress

    EPA Science Inventory

    RATIONALE. Exposure to ambient particulate matter (PM) has been associated with adverse health effects including inflammatory responses in the lung. Diesel exhaust particles (DEP) are a ubiquitous contributor to the fine and ultrafine PM burden in ambient air. Toxicological studi...

  10. Exposure for ultrafine carbon particles at levels below detectable pulmonary inflammation affects cardiovascular performance in spontaneously hypertensive rats*

    EPA Science Inventory

    Rationale: Exposure to particulate matter is a risk factor for cardiopulmonary disease but the related molecular mechanisms are poorly understood. Previously we studied cardiovascular responses in healthy WKY rats following inhalation exposure to ultrafine carbon particles (UfCPs...

  11. The exposure to coarse, fine and ultrafine particle emissions from concrete mixing, drilling and cutting activities.

    PubMed

    Azarmi, Farhad; Kumar, Prashant; Mulheron, Mike

    2014-08-30

    Building activities generate coarse (PM10≤10μm), fine (PM2.5≤2.5μm) and ultrafine particles (<100nm) making it necessary to understand both the exposure levels of operatives on site and the dispersion of ultrafine particles into the surrounding environment. This study investigates the release of particulate matter, including ultrafine particles, during the mixing of fresh concrete (incorporating Portland cement with Ground Granulated Blastfurnace Slag, GGBS or Pulverised Fuel Ash, PFA) and the subsequent drilling and cutting of hardened concrete. Particles were measured in the 5-10,000nm size range using a GRIMM particle spectrometer and a fast response differential mobility spectrometer (DMS50). The mass concentrations of PM2.5-10 fraction contributed ∼52-64% of total mass released. The ultrafine particles dominated the total particle number concentrations (PNCs); being 74, 82, 95 and 97% for mixing with GGBS, mixing with PFA, drilling and cutting, respectively. Peak values measured during the drilling and cutting activities were 4 and 14 times the background. Equivalent emission factors were calculated and the total respiratory deposition dose rates for PNCs for drilling and cutting were 32.97±9.41×10(8)min(-1) and 88.25±58.82×10(8)min(-1). These are a step towards establishing number and mass emission inventories for particle exposure during construction activities. PMID:25068443

  12. Diesel Exhaust-Induced Pulmonary and Cardiovascular Impairment: The Role of Hypertension Intervention

    EPA Science Inventory

    Background–Exposure to diesel exhaust (DE) particles and associated gases is linked to cardiovascular impairments; however the susceptibility of hypertensive individuals is less well understood. Objective–1) To determine cardiopulmonary effects of gas-phase versus whole-DE, and 2...

  13. Effects of exposure to heavy particles and aging on object recognition memory in rats

    NASA Astrophysics Data System (ADS)

    Rabin, Bernard; Joseph, James; Shukitt-Hale, Barbara; Carrihill-Knoll, Kirsty; Shannahan, Ryan; Hering, Kathleen

    Exposure to HZE particles produces changes in neurocognitive performance. These changes, including deficits in spatial learning and memory, object recognition memory and operant responding, are also observed in the aged organism. As such, it has been proposed that exposure to heavy particles produces "accelerated aging". Because aging is an ongoing process, it is possible that there would be an interaction between the effects of exposure and the effects of aging, such that doses of HZE particles that do not affect the performance of younger organisms will affect the performance of organisms as they age. The present experiments were designed to test the hypothesis that young rats that had been exposed to HZE particles would show a progressive deterioration in object recognition memory as a function of the age of testing. Rats were exposed to 12 C, 28 S or 48 Ti particles at the N.A.S.A. Space Radiation Laboratory at Brookhaven National Laboratory. Following irradiation the rats were shipped to UMBC for behavioral testing. HZE particle-induced changes in object recognition memory were tested using a standard procedure: rats were placed in an open field and allowed to interact with two identical objects for up to 30 sec; twenty-four hrs later the rats were again placed in the open field, this time containing one familiar and one novel object. Non-irradiated control animals spent significantly more time with the novel object than with the familiar object. In contrast, the rats that been exposed to heavy particles spent equal amounts of time with both the novel and familiar object. The lowest dose of HZE particles which produced a disruption of object recognition memory was determined three months and eleven months following exposure. The threshold dose needed to disrupt object recognition memory three months following irradiation varied as a function of the specific particle and energy. When tested eleven months following irradiation, doses of HZE particles that did

  14. Multi-metric measurement of personal exposure to ultrafine particles in selected urban microenvironments

    NASA Astrophysics Data System (ADS)

    Spinazzè, Andrea; Cattaneo, Andrea; Scocca, Damiano R.; Bonzini, Matteo; Cavallo, Domenico M.

    2015-06-01

    At the beginning of the study, our hypothesis was that visiting certain microenvironments (MEs) is one of the most important determinants of personal exposure to ultrafine particles (UFP) and that moving between microenvironments significantly differentiates exposure. The overall aim of this study is to perform relevant exposure measurements to extend our knowledge on environmental exposure to UFP in urban environments. The UFP concentrations in different urban MEs were measured by personal monitoring in repeated sampling campaigns along a fixed route. The measurement runs were performed on one-week periods and at different times of day (AM: 08.00-10.30; PM: 16.00-18.30) and repeated in different periods of the year (winter, spring, summer, and autumn) for a total of 56 runs (>110 h). Measurements included on-line monitoring of the UFP particle number concentration (PNC), mean diameter (mean-d) and lung-deposited surface-area (LDSA). Additionally, the PNC, particle mass concentration (PMC) profiles for quasi-ultrafine particles (QUFP; PM0.25) were estimated. A significant seasonal difference in the PNC and PMC, mean diameter and surface area was observed as well as between different times of the day and days of the week. In addition, differences in the UFP concentrations were also found in each ME, and there were specific mean-diameter and surface area concentrations. In general, the mean particle diameters showed an inverse relationship with the PNC, while the LDSA had the opposite behaviour. Appreciable differences among all MEs and monitoring periods were observed; the concentration patterns and variations seemed related to the typical sources of urban pollutants (traffic), proximity to sources and time of day. The highest exposures were observed for walking or biking along high-trafficked routes and while using public buses. The UFP exposure levels in modern cars, equipped with high-efficiency filters and in air recirculation mode, were significantly lower.

  15. Effects of particle exposure and particle-elicited inflammatory cells on mutation in rat alveolar epithelial cells.

    PubMed

    Driscoll, K E; Deyo, L C; Carter, J M; Howard, B W; Hassenbein, D G; Bertram, T A

    1997-02-01

    To investigate mechanisms underlying development of lung adenomas and carcinomas in rats exposed to poorly soluble particles the relationships between particle exposure, inflammation and mutagenesis in rat alveolar type II cells were characterized. Rats were exposed to saline or saline suspensions of 10 and 100 mg/kg of alpha-quartz, carbon black or titanium dioxide by intratracheal instillation. Fifteen months after exposure, bronchoalveolar lavage (BAL) cells were characterized as to number and type and lung histopathology performed. The alveolar type II cells were isolated and cultured in 6 thioguanine (6TG) containing media to select for mutation in the hprt gene. The potential contribution of lung inflammatory cells to in vivo mutagenic responses, were evaluated by co-culturing BAL cells with the rat alveolar epithelial cell line, RLE-6TN for 24 h and the RLE-6TN cells selected for 6TG resistance. Neutrophilic inflammation was detected in all rats exposed to 10 and 100 mg/kg of alpha-quartz and carbon black and 100 mg/kg titanium dioxide; epithelial hyperplasia was observed in rats exposed to 10 and 100 mg/kg of alpha-quartz and 100 mg/kg carbon black. Hprt mutation frequency was increased in alveolar type II cells from rats exposed to 10 and 100 mg/kg of alpha-quartz, 100 mg/kg carbon black and 100 mg/kg titanium dioxide. In vitro exposure of RLE-6TN cells to BAL cells from rats treated with 10 and 100 mg/kg of alpha-quartz or 100 mg/kg carbon black increased hprt mutant frequency. Both macrophage and neutrophil enriched BAL cell populations were mutagenic to RLE-6TN cells, however, the mutagenic activity appeared greatest for neutrophils. Addition of catalase to BAL cell:RLE-6TN co-cultures inhibited the increase in hprt mutation frequency. These studies demonstrate exposure of rats to doses of particles producing significant neutrophilic inflammation is associated with increased mutation in rat alveolar type II cells. The ability of particle

  16. Protective effects of blueberry- and strawberry diets on neuronal stress following exposure to (56)Fe particles.

    PubMed

    Poulose, Shibu M; Bielinski, Donna F; Carrihill-Knoll, Kirsty L; Rabin, Bernard M; Shukitt-Hale, Barbara

    2014-12-17

    Particles of high energy and charge (HZE particles), which are abundant outside the magnetic field of the Earth, have been shown to disrupt the functioning of neuronal communication in critical regions of the brain. Previous studies with HZE particles, have shown that irradiation produces enhanced indices of oxidative stress and inflammation as well as altered neuronal function that are similar to those seen in aging. Feeding animals antioxidant-rich berry diets, specifically blueberries and strawberries, countered the deleterious effects of irradiation by reducing oxidative stress and inflammation, thereby improving neuronal signaling. In the current study, we examined the effects of exposure to (56)Fe particles in critical regions of brain involved in cognitive function, both 36h and 30 days post irradiation. We also studied the effects of antioxidant-rich berry diets, specifically a 2% blueberry or strawberry diet, fed for 8 weeks prior to radiation as well as 30 days post irradiation. (56)Fe exposure caused significant differential, neurochemical changes in critical regions of the brain, such as hippocampus, striatum, frontal cortex, and cerebellum, through increased inflammation, and increased oxidative stress protein markers. (56)Fe exposure altered the autophagy markers, and antioxidant-rich berry diets significantly reduced the accumulation of p62 in hippocampus, a scaffold protein that co-localizes with ubiquitinated protein at the 30 days post irradiation time-point. Exposure to (56)Fe particles increased the accumulation of disease-related proteins such as PHF-tau in the hippocampus of animals fed the control diet, but not in the irradiated animals fed the blueberry diet. These results indicate the potential protective effects of antioxidant-rich berry diets on neuronal functioning following exposure to HZE particles. PMID:25451098

  17. A practical alpha particle irradiator for studying internal alpha particle exposure.

    PubMed

    Lee, Ki-Man; Lee, Ui-Seob; Kim, Eun-Hee

    2016-09-01

    An alpha particle irradiator has been built in the Radiation Bioengineering Laboratory at Seoul National University (SNU) to investigate the cellular responses to alpha emissions from radon and the progeny. This irradiator is designed to have the energy of alpha particles entering target cells similar to that of alpha emissions from the radon progeny Po-218 and Po-214 residing in the human respiratory tract. For the SNU alpha particle irradiator, an irradiation system is equipped with cell dishes of 4µm thick Mylar bottom and a special setup of cells on slide for gamma-H2AX assay. Dose calibration for the alpha particle irradiator was performed by dual approaches, detection and computer simulation, in consideration of the source-to-target distance (STD) and the size of a cell dish. The uniformity of dose among cells in a dish is achieved by keeping the STD and the size of cell dish in certain ranges. The performance of the SNU alpha particle irradiator has been proven to be reliable through the gamma-H2AX assay with the human lung epithelial cells irradiated. PMID:27475622

  18. Contribution of particle counting in assessment of exposure to airborne microorganisms

    NASA Astrophysics Data System (ADS)

    Parat, Sylvie; Perdrix, Alain; Mann, Sylvie; Baconnier, Pierre

    The aim of the study was to determine the relationship between airborne bacterial concentrations and particle counts measured simultaneously at different sites. Andersen single stage viable particle samplers were used for microbial measurements while a Laser particle counter gave the cumulated counts of particles larger than 0.5 μm diameter. The first phase of the study was performed in two experimental rooms where the basic level of microbial contamination was low. Peaks of concentrations were generated by human activity and both bacterial and particle counts were monitored over 1 h. In the second phase, measurements were run for several days in three different buildings normally occupied. Natural variations of bacterial and particle counts were monitored: microbial measurements were performed each hour while particle counts were started with a 10 min frequency. Statistics revealed strong positive correlations between bacterial and particle counts in four sites out of five. Analyses of covariance used to compare the regression lines obtained in each area showed that except for two natural sites, the regression lines were significantly different, indicating that no absolute relationship can be established between the two parameters. Therefore, particle counting should, of course, not take the place of microorganism measurements, but combining particle counting with bioaerosols measurements may allow detection of rapid variations instantaneously and indicate further microbial measurements. This strategy should improve the assessment of people"s real exposure to airborne microorganisms.

  19. Characterization, Exposure Measurement and Control for Nanoscale Particles in Workplaces and on the Road

    NASA Astrophysics Data System (ADS)

    Wang, Jing; Pui, David Y. H.

    2011-07-01

    The amount of engineered nanoparticles is increasing at a rapid rate and more concerns are being raised about the occupational health and safety of nanoparticles in the workplace, and implications of nanotechnology on the environment and living systems. At the same time, diesel engine emissions are one of the serious air pollution sources in urban area. Ultrafine particles on the road can result in harmful effects on the health of drivers and passengers. Research on characterization, exposure measurement and control is needed to address the environmental, health and safety issues of nanoscale particles. We present results of our studies on airborne particles in workplaces and on the road.

  20. Exposure to ultrafine particles and PM 2.5 in four Sydney transport modes

    NASA Astrophysics Data System (ADS)

    Knibbs, Luke D.; de Dear, Richard J.

    2010-08-01

    Concentrations of ultrafine (<0.1 μm) particles (UFPs) and PM 2.5 (<2.5 μm) were measured whilst commuting along a similar route by train, bus, ferry and automobile in Sydney, Australia. One trip on each transport mode was undertaken during both morning and evening peak hours throughout a working week, for a total of 40 trips. Analyses comprised one-way ANOVA to compare overall (i.e. all trips combined) geometric mean concentrations of both particle fractions measured across transport modes, and assessment of both the correlation between wind speed and individual trip means of UFPs and PM 2.5, and the correlation between the two particle fractions. Overall geometric mean concentrations of UFPs and PM 2.5 ranged from 2.8 (train) to 8.4 (bus) × 10 4 particles cm -3 and 22.6 (automobile) to 29.6 (bus) μg m -3, respectively, and a statistically significant difference ( p < 0.001) between modes was found for both particle fractions. Individual trip geometric mean concentrations were between 9.7 × 10 3 (train) and 2.2 × 10 5 (bus) particles cm -3 and 9.5 (train) to 78.7 (train) μg m -3. Estimated commuter exposures were variable, and the highest return trip mean PM 2.5 exposure occurred in the ferry mode, whilst the highest UFP exposure occurred during bus trips. The correlation between fractions was generally poor, and in keeping with the duality of particle mass and number emissions in vehicle-dominated urban areas. Wind speed was negatively correlated with, and a generally poor determinant of, UFP and PM 2.5 concentrations, suggesting a more significant role for other factors in determining commuter exposure.

  1. Exposure to ultrafine and fine particles and noise during cycling and driving in 11 Dutch cities

    NASA Astrophysics Data System (ADS)

    Boogaard, Hanna; Borgman, Frank; Kamminga, Jaap; Hoek, Gerard

    Recent studies have suggested that exposures during traffic participation may be associated with adverse health effects. Traffic participation involves relatively short but high exposures. Potentially relevant exposures include ultrafine particles, fine particles (PM 2.5) and noise. Simultaneously, detailed real time exposure of particle number concentration (PNC), PM 2.5 and noise has been measured while driving and cycling 12 predefined routes of approximately 10-20 min duration. Sampling took place in eleven medium-sized Dutch cities on eleven weekdays in August till October 2006. To investigate variability in cyclists exposure, we systematically collected information on meteorology, GPS coordinates, type of road, traffic intensity, passing vehicles and mopeds while cycling. The overall mean PNC of car drivers was 5% higher than the mean PNC of cyclists. The overall mean concentration of PM 2.5 in the car was 11% higher than during cycling. Slightly higher 1-min peak concentrations were measured in the car (PNC 14%; PM 2.5 29% for 95-percentiles). Shorter duration peaks of PNC were higher during cycling (43% for 99-percentile of 1-s averages). Peaks in PNC typically last for less than 10 s. A large variability of exposure was found within and between routes. Factors that significantly predicted PNC variability during cycling were: passing vehicles (mopeds, cars), waiting for traffic lights, passing different types of (large) intersections and bicycle lanes and bike paths close to motorized traffic. No relation was found between PM 2.5 and those predictor variables. The correlation between PNC and noise was moderate (median 0.34). PM 2.5 had very low correlations with PNC and noise. PNC and PM 2.5 exposure of car drivers was slightly higher than that of cyclists. PNC was largely uncorrelated with PM 2.5 and reflected local traffic variables more than PM 2.5. Different factors were associated with high PNC and high noise exposures.

  2. The influence of diesel-truck exhaust particles on the kinetics of the atmospheric oxidation of dissolved sulfur dioxide by oxygen.

    PubMed

    Meena, Vimlesh Kumar; Dhayal, Yogpal; Saxena, Deepa; Rani, Ashu; Chandel, C P Singh; Gupta, K S

    2016-09-01

    The automobile exhausts are one of the major sources of particulate matter in urban areas and these particles are known to influence the atmospheric chemistry in a variety of ways. Because of this, the oxidation of dissolved sulfur dioxide by oxygen was studied in aqueous suspensions of particulates, obtained by scraping the particles deposited inside a diesel truck exhaust pipe (DEP). A variation in pH showed the rate to increase with increase in pH from 5.22 to about ∼6.3 and to decrease thereafter becoming very slow at pH = 8.2. In acetate-buffered medium, the reaction rate was higher than the rate in unbuffered medium at the same pH. Further, the rate was found to be higher in suspension than in the leachate under otherwise identical conditions. And, the reaction rate in the blank reaction was the slowest. This appears to be due to catalysis by leached metal ions in leachate and due to catalysis by leached metal ions and particulate surface both in suspensions. The kinetics of dissolved SO2 oxidation in acetate-buffered medium as well as in unbuffered medium at pH = 5.22 were defined by rate law: k obs  = k 0 + k cat [DEP], where k obs and k 0 are observed rate constants in the presence and the absence of DEP and k cat is the rate constant for DEP-catalyzed pathway. At pH = 8.2, the reaction rate was strongly inhibited by DEP in buffered and unbuffered media. Results suggest that the DEP would have an inhibiting effect in those areas where rainwater pH is 7 or more. These results at high pH are of particular significance to the Indian subcontinent, because of high rainwater pH. Conversely, it indicates the DEP to retard the oxidation of dissolved SO2 and control rainwater acidification. PMID:27230141

  3. PARTICLE TOTAL EXPOSURE ASSESSMENT METHODOLOGY (PTEAM): RIVERSIDE, CALIFORNIA PILOT STUDY - VOLUME I

    EPA Science Inventory

    The goal of this study was to estimate the frequency distribution of exposure of an urban population to inhalable particles (less than 10 micrometers in diameter). Probability sampling design was used to select 178 nonsmoking residents aged 10 or above in Riverside, CA. Each pers...

  4. Cognitive effects of partial and whole body exposures to 160 particles

    Technology Transfer Automated Retrieval System (TEKTRAN)

    When rats and mice are exposed to HZE particles at the NASA Space Radiation Laboratory (NSRL) at Brookhaven National Laboratory to simulate the effect of exposure to space radiation on cognitive performance, there may be differences in the amount of tissue that is irradiated: some experimenters irra...

  5. RESPIRABLE PARTICLES AND MISTS IN MOUSE PULMONARY INFECTIVITY MODEL. EFFECT OF CHRONIC OR INTERMITTENT EXPOSURE

    EPA Science Inventory

    The effects of respirable-sized sulfuric acid mist or mixtures containing acid mist and carbon particles (A-C) on the susceptibility to bacterial and viral respiratory infection were studied in mice and hamsters. Both species showed mortalities upon single 3-hour exposure to 600 ...

  6. Analysis of Exposure-Dose Variation of Inhaled Particles in Adult Subjects.

    EPA Science Inventory

    Although internal dose is a key factor for determining the health risk of inhaled pollutant particles, available dose information is largely limited to young healthy adults under a few typical exposure conditions. Extrapolation of the limited dose information to different populat...

  7. Interaction between age and exposure to 56Fe particles on behavior and neurochemistry

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Previous research has shown that exposure to HZE particles, which will be encountered on long-term space missions, can adversely affect the ability of rats to perform a variety of behavioral tasks. This outcome has implications for an astronaut's ability to successfully complete requirements associ...

  8. Exposure to concentrated coarse air pollution particles causes mild cardiopulmonary effects in young healthy adults

    EPA Science Inventory

    Rationale: There is ample epidemiological and toxicological evidence that exposure to fme air pollution particles (PM2.5), which are primarily derived from combustion processes, can result in increased mortality and morbidity. There is less certainty as to the contribution of coa...

  9. School children's personal exposure to ultrafine particles in the urban environment.

    PubMed

    Mazaheri, Mandana; Clifford, Sam; Jayaratne, Rohan; Megat Mokhtar, Megat Azman; Fuoco, Fernanda; Buonanno, Giorgio; Morawska, Lidia

    2014-01-01

    There has been considerable scientific interest in personal exposure to ultrafine particles (UFP). In this study, the inhaled particle surface area doses and dose relative intensities in the tracheobronchial and alveolar regions of lungs were calculated using measured 24-h UFP time series of school children personal exposures. Bayesian hierarchical modeling was used to determine mean doses and dose intensities for the various microenvironments. Analysis of measured personal exposures for 137 participating children from 25 schools in the Brisbane Metropolitan Area showed similar trends for all participating children. Bayesian regression modeling was performed to calculate the daily proportion of children's total doses in different microenvironments. The proportion of total daily alveolar doses for home, school, commuting, and other were 55.3%, 35.3%, 4.5%, and 5.0%, respectively, with the home microenvironment contributing a majority of children's total daily dose. Children's mean indoor dose was never higher than the outdoor's at any of the schools, indicating there were no persistent indoor particle sources in the classrooms during the measurements. Outdoor activities, eating/cooking at home, and commuting were the three activities with the highest dose intensities. Children's exposure during school hours was more strongly influenced by urban background particles than traffic near the school. PMID:24274338

  10. USE OF METAL- AND FLUORESCEIN-TAGGED MATERIALS TO STUDY SETTLED PARTICLES EXPOSURE PATHWAYS

    EPA Science Inventory

    Through the use of ten size ranges of tagged materials (Antley et. al., 2000a), inductively coupled plasma- mass spectrometry (ICP-MS) and flourometry are being used to study the movement of settled particles in the indoor environment, exposure pathways, and the collection effi...

  11. A single-particle characterization of a mobile Versatile Aerosol Concentration Enrichment System for exposure studies

    PubMed Central

    Freney, Evelyn J; Heal, Mathew R; Donovan, Robert J; Mills, Nicholas L; Donaldson, Kenneth; Newby, David E; Fokkens, Paul HB; Cassee, Flemming R

    2006-01-01

    Background An Aerosol Time-of-Flight Mass Spectrometer (ATOFMS) was used to investigate the size and chemical composition of fine concentrated ambient particles (CAPs) in the size range 0.2–2.6 μm produced by a Versatile Aerosol Concentration Enrichment System (VACES) contained within the Mobile Ambient Particle Concentrator Exposure Laboratory (MAPCEL). The data were collected during a study of human exposure to CAPs, in Edinburgh (UK), in February-March 2004. The air flow prior to, and post, concentration in the VACES was sampled in turn into the ATOFMS, which provides simultaneous size and positive and negative mass spectral data on individual fine particles. Results The particle size distribution was unaltered by the concentrator over the size range 0.2–2.6 μm, with an average enrichment factor during this study of ~5 (after dilution of the final air stream). The mass spectra from single particles were objectively grouped into 20 clusters using the multivariate K-means algorithm and then further grouped manually, according to similarity in composition and time sequence, into 8 main clusters. The particle ensemble was dominated by pure and reacted sea salt and other coarse inorganic dusts (as a consequence of the prevailing maritime-source climatology during the study), with relatively minor contributions from carbonaceous and secondary material. Very minor variations in particle composition were noted pre- and post-particle concentration, but overall there was no evidence of any significant change in particle composition. Conclusion These results confirm, via single particle analysis, the preservation of the size distribution and chemical composition of fine ambient PM in the size range 0.2–2.6 μm after passage through the VACES concentration instrumentation. PMID:16723024

  12. Protective effects of pulmonary epithelial lining fluid on oxidative stress and DNA single-strand breaks caused by ultrafine carbon black, ferrous sulphate and organic extract of diesel exhaust particles

    SciTech Connect

    Chuang, Hsiao-Chi; Cheng, Yi-Ling; Lei, Yu-Chen; Chang, Hui-Hsien; Cheng, Tsun-Jen

    2013-02-01

    Pulmonary epithelial lining fluid (ELF) is the first substance to make contact with inhaled particulate matter (PM) and interacts chemically with PM components. The objective of this study was to determine the role of ELF in oxidative stress, DNA damage and the production of proinflammatory cytokines following physicochemical exposure to PM. Ultrafine carbon black (ufCB, 15 nm; a model carbonaceous core), ferrous sulphate (FeSO{sub 4}; a model transition metal) and a diesel exhaust particle (DEP) extract (a model organic compound) were used to examine the acellular oxidative potential of synthetic ELF and non-ELF systems. We compared the effects of exposure to ufCB, FeSO{sub 4} and DEP extract on human alveolar epithelial Type II (A549) cells to determine the levels of oxidative stress, DNA single-strand breaks and interleukin-8 (IL-8) production in ELF and non-ELF systems. The effects of ufCB and FeSO{sub 4} on the acellular oxidative potential, cellular oxidative stress and DNA single-strand breakage were mitigated significantly by the addition of ELF, whereas there was no decrease following treatment with the DEP extract. There was no significant effect on IL-8 production following exposure to samples that were suspended in ELF/non-ELF systems. The results of the present study indicate that ELF plays an important role in the initial defence against PM in the pulmonary environment. Experimental components, such as ufCB and FeSO{sub 4}, induced the production of oxidative stress and led to DNA single-strand breaks, which were moderately prevented by the addition of ELF. These findings suggest that ELF plays a protective role against PM-driven oxidative stress and DNA damage. -- Highlights: ► To determine the role of ELF in ROS, DNA damage and IL-8 after exposure to PM. ► ufCB, FeSO{sub 4} and DEP extract were used to examine the protective effects of ELF. ► PM-driven oxidative stress and DNA single-strand breakage were mitigated by ELF. ► The findings

  13. Behavioral and neurochemical abnormalities after exposure to low doses of high-energy iron particles.

    PubMed

    Hunt, W A; Joseph, J A; Rabin, B M

    1989-01-01

    Exposure of rats to high-energy iron particles (600 MeV/amu) has been found to alter behavior after doses as low as 10 rads. The performance of a task that measures upper body strength was significantly degraded after irradiation. In add