Spatial and temporal associations of road traffic noise and air pollution in London: Implications for epidemiological studies.

Science.gov (United States)

Fecht, Daniela; Hansell, Anna L; Morley, David; Dajnak, David; Vienneau, Danielle; Beevers, Sean; Toledano, Mireille B; Kelly, Frank J; Anderson, H Ross; Gulliver, John

2016-03-01

Road traffic gives rise to noise and air pollution exposures, both of which are associated with adverse health effects especially for cardiovascular disease, but mechanisms may differ. Understanding the variability in correlations between these pollutants is essential to understand better their separate and joint effects on human health. We explored associations between modelled noise and air pollutants using different spatial units and area characteristics in London in 2003-2010. We modelled annual average exposures to road traffic noise (LAeq,24h, Lden, LAeq,16h, Lnight) for ~190,000 postcode centroids in London using the UK Calculation of Road Traffic Noise (CRTN) method. We used a dispersion model (KCLurban) to model nitrogen dioxide, nitrogen oxide, ozone, total and the traffic-only component of particulate matter ≤2.5μm and ≤10μm. We analysed noise and air pollution correlations at the postcode level (~50 people), postcodes stratified by London Boroughs (~240,000 people), neighbourhoods (Lower layer Super Output Areas) (~1600 people), 1km grid squares, air pollution tertiles, 50m, 100m and 200m in distance from major roads and by deprivation tertiles. Across all London postcodes, we observed overall moderate correlations between modelled noise and air pollution that were stable over time (Spearman's rho range: |0.34-0.55|). Correlations, however, varied considerably depending on the spatial unit: largest ranges were seen in neighbourhoods and 1km grid squares (both Spearman's rho range: |0.01-0.87|) and was less for Boroughs (Spearman's rho range: |0.21-0.78|). There was little difference in correlations between exposure tertiles, distance from road or deprivation tertiles. Associations between noise and air pollution at the relevant geographical unit of analysis need to be carefully considered in any epidemiological analysis, in particular in complex urban areas. Low correlations near roads, however, suggest that independent effects of road noise and

Road traffic air and noise pollution exposure assessment - A review of tools and techniques.

Science.gov (United States)

Khan, Jibran; Ketzel, Matthias; Kakosimos, Konstantinos; Sørensen, Mette; Jensen, Steen Solvang

2018-09-01

Road traffic induces air and noise pollution in urban environments having negative impacts on human health. Thus, estimating exposure to road traffic air and noise pollution (hereafter, air and noise pollution) is important in order to improve the understanding of human health outcomes in epidemiological studies. The aims of this review are (i) to summarize current practices of modelling and exposure assessment techniques for road traffic air and noise pollution (ii) to highlight the potential of existing tools and techniques for their combined exposure assessment for air and noise together with associated challenges, research gaps and priorities. The study reviews literature about air and noise pollution from urban road traffic, including other relevant characteristics such as the employed dispersion models, Geographic Information System (GIS)-based tool, spatial scale of exposure assessment, study location, sample size, type of traffic data and building geometry information. Deterministic modelling is the most frequently used assessment technique for both air and noise pollution of short-term and long-term exposure. We observed a larger variety among air pollution models as compared to the applied noise models. Correlations between air and noise pollution vary significantly (0.05-0.74) and are affected by several parameters such as traffic attributes, building attributes and meteorology etc. Buildings act as screens for the dispersion of pollution, but the reduction effect is much larger for noise than for air pollution. While, meteorology has a greater influence on air pollution levels as compared to noise, although also important for noise pollution. There is a significant potential for developing a standard tool to assess combined exposure of traffic related air and noise pollution to facilitate health related studies. GIS, due to its geographic nature, is well established and has a significant capability to simultaneously address both exposures. Copyright �

Modeling near-road air quality using a computational fluid dynamics model, CFD-VIT-RIT.

Science.gov (United States)

Wang, Y Jason; Zhang, K Max

2009-10-15

It is well recognized that dilution is an important mechanism governing the near-road air pollutant concentrations. In this paper, we aim to advance our understanding of turbulent mixing mechanisms on and near roadways using computation fluid dynamics. Turbulent mixing mechanisms can be classified into three categories according to their origins: vehicle-induced turbulence (VIT), road-induced turbulence (RIT), and atmospheric boundary layer turbulence. RIT includes the turbulence generated by road embankment, road surface thermal effects, and roadside structures. Both VIT and RIT are affected by the roadway designs. We incorporate the detailed treatment of VIT and RIT into the CFD (namely CFD-VIT-RIT) and apply the model in simulating the spatial gradients of carbon monoxide near two major highways with different traffic mix and roadway configurations. The modeling results are compared to the field measurements and those from CALINE4 and CFD without considering VIT and RIT. We demonstrate that the incorporation of VIT and RIT considerably improves the modeling predictions, especially on vertical gradients and seasonal variations of carbon monoxide. Our study implies that roadway design can significantly influence the near-road air pollution. Thus we recommend that mitigating near-road air pollution through roadway designs be considered in the air quality and transportation management In addition, thanks to the rigorous representation of turbulent mixing mechanisms, CFD-VIT-RIT can become valuable tools in the roadway designs process.

Operational evaluation of the RLINE dispersion model for studies of traffic-related air pollutants

Science.gov (United States)

Milando, Chad W.; Batterman, Stuart A.

2018-06-01

Exposure to traffic-related air pollutants (TRAP) remains a key public health issue, and improved exposure measures are needed to support health impact and epidemiologic studies and inform regulatory responses. The recently developed Research LINE source model (RLINE), a Gaussian line source dispersion model, has been used in several epidemiologic studies of TRAP exposure, but evaluations of RLINE's performance in such applications have been limited. This study provides an operational evaluation of RLINE in which predictions of NOx, CO and PM2.5 are compared to observations at air quality monitoring stations located near high traffic roads in Detroit, MI. For CO and NOx, model performance was best at sites close to major roads, during downwind conditions, during weekdays, and during certain seasons. For PM2.5, the ability to discern local and particularly the traffic-related portion was limited, a result of high background levels, the sparseness of the monitoring network, and large uncertainties for certain processes (e.g., formation of secondary aerosols) and non-mobile sources (e.g., area, fugitive). Overall, RLINE's performance in near-road environments suggests its usefulness for estimating spatially- and temporally-resolved exposures. The study highlights considerations relevant to health impact and epidemiologic applications, including the importance of selecting appropriate pollutants, using appropriate monitoring approaches, considering prevailing wind directions during study design, and accounting for uncertainty.

Diurnal variation of on-road air pollution in an urban street canyon in Seoul

Science.gov (United States)

Ho, Woo, Sung; Lee, Seung-Bok; Kim, Kyung Hwan; Bae, Gwi-Nam; Sunwoo, Young; Ma, Young-Il; Han, Dokyoung; Song, Sanghoo

2014-05-01

Motor vehicles are a major source of CO, NOx and particulate matters. Especially, in the surroundings of high-raised buildings, so-called an urban street canyon, air pollution levels increase due to limited dispersion of vehicle emissions. In this study, a mobile laboratory was used to measure diurnal variation of on-road concentrations of air pollutants such as NOx, particle-bound polycyclic aromatic hydrocarbons, black carbon and particle number in the urban street canyon on the Teheran road with eight lanes in Seoul, Korea from 5th to 8th November 2013. Each traveling distance was about 3.3km. Traveling vehicle at the middle of the Teheran road was recorded by video camera, and then the car counting by vehicle types. On road measurements conducted for 3~6 hours per day. Hourly average of air pollutant concentration in morning rush hour more than two times higher than those at the daybreak. We will analyze the correlation between air pollution levels and traffic volume by vehicle types. We will discuss about spatial characteristics of on-road air pollution levels in the urban street canyon.

Characteristics of air pollutant dispersion around a high-rise building

International Nuclear Information System (INIS)

Zhang, Y.; Kwok, K.C.S.; Liu, X.-P.; Niu, J.-L.

2015-01-01

A numerical wind tunnel model was proposed. The computed results of the pollutant diffusion around a typical Hong Kong high-rise building model (at a linear scale of 1:30), were found to show a similar trend to the outcomes of self-conducted experimental measurements that the pathways of pollutant migration for windward and leeward pollutant emission are different. For the case with windward pollutant emission at the 3rd floor within a re-entry, the pollutant migrated downwards due to the downwash created by the wind. In contrast, for the case with leeward pollution emission, dispersion is dominated by intense turbulent mixing in the near wake and characterized by the upward migration of the pollutant in the leeward re-entry. The simulated results of haze-fog (HF) studies confirm that the pathway of pollutant migration is dominated by wind–structure interaction and buoyancy effect only plays a minor role in the dispersion process. - Highlights: • A self-developed numerical wind tunnel model was proposed. • Characteristics of air pollutant dispersion with windward/leeward emission were discussed. • Wind–structure interaction controls the air pollutant dispersion around the building. - The different characteristics of air pollutant dispersion around a high-rise building, for both cases of a dispersion source in either the windward face or leeward face, are dominated by wind–structure interaction, with buoyancy effect playing only a minor role

Near-road air pollution impacts of goods movement in communities adjacent to the Ports of Los Angeles and Long Beach

Science.gov (United States)

Kozawa, Kathleen H.; Fruin, Scott A.; Winer, Arthur M.

A mobile platform was outfitted with real-time instruments to spatially characterize pollution concentrations in communities adjacent to the Ports of Los Angeles and Long Beach, communities heavily impacted by emissions related to dieselized goods movement, with the highest localized air pollution impacts due to heavy-duty diesel trucks (HDDT). Measurements were conducted in the winter and summer of 2007 on fixed routes driven both morning and afternoon. Diesel-related pollutant concentrations such as black carbon, nitric oxide, ultrafine particles, and particle-bound polycyclic aromatic hydrocarbons were frequently elevated two to five times within 150 m downwind of freeways (compared to more than 150 m) and up to two times within 150 m downwind of arterial roads with significant amounts of diesel traffic. While wind direction was the dominant factor associated with downwind impacts, steady and consistent wind direction was not required to produce; high impacts were observed when a given area was downwind of a major roadway for any significant fraction of time. This suggests elevated pollution impacts downwind of freeways and of busy arterials are continuously occurring on one side of the road or the other, depending on wind direction. The diesel truck traffic in the area studied was high, with more than 2000 trucks per peak hour on the freeway and two- to six-hundred trucks per hour on the arterial roads studied. These results suggest that similarly-frequent impacts occur throughout urban areas in rough proportion to diesel truck traffic fractions. Thus, persons living or working near and downwind of busy roadways can have several-fold higher exposures to diesel vehicle-related pollution than would be predicted by ambient measurements in non-impacted locations.

The influence of roadside solid and vegetation barriers on near-road air quality

Science.gov (United States)

Ghasemian, Masoud; Amini, Seyedmorteza; Princevac, Marko

2017-12-01

The current study evaluates the influence of roadside solid and vegetation barriers on the near-road air quality. Reynolds Averaged Navier-Stokes (RANS) technique coupled with the k - ε realizable turbulence model is utilized to investigate the flow pattern and pollutant concentration. A scalar transport equation is solved for a tracer gas to represent the roadway pollutant emissions. In addition, a broad range of turbulent Schmidt numbers are tested to calibrate the scalar transport equation. Three main scenarios including flat terrain, solid barrier, and vegetative barrier are studied. To validate numerical methodology, predicted pollutant concentration is compared with published wind tunnel data. Results show that the solid barrier induces an updraft motion and lofts the vehicle emission plume. Therefore, the ground-level pollutant concentration decreases compared to the flat terrain. For the vegetation barrier, different sub-scenarios with different vegetation densities ranging from approximately flat terrain to nearly solid barrier are examined. Dense canopies act in a similar manner as a solid barrier and mitigate the pollutant concentration through vertical mixing. On the other hand, the high porosity vegetation barriers reduce the wind speed and lead to a higher pollutant concentration. As the vegetation density increases, i.e. the barrier porosity decreases, the recirculation zone behind the canopy becomes larger and moves toward the canopy. The dense plant canopy with LAD = 3.33m-2m3 can improve the near-road air quality by 10% and high porosity canopy with LAD = 1m-2m3 deteriorates near-road air quality by 15%. The results of this study can be implemented as green infrastructure design strategies by urban planners and forestry organizations.

Urban snow indicates pollution originating from road traffic.

Science.gov (United States)

Kuoppamäki, Kirsi; Setälä, Heikki; Rantalainen, Anna-Lea; Kotze, D Johan

2014-12-01

Traffic is a major source of pollutants in cities. In this well-replicated study we analysed a broad array of contaminants in snowpacks along roads of different traffic intensities. The majority of pollutants showed a similar pattern with respect to traffic intensity: pH and conductivity as well as concentrations of PAHs, total suspended solids, phosphorus and most heavy metals were higher next to high intensity roads compared to low intensity roads. These pollutant levels also decreased considerably up to 5 m distance from the roads. Furthermore, apart from nitrogen, these variables increased in concentration from control sites in urban forest patches to road bank sites next to roads of low, intermediate and high traffic intensities. The deposition pattern of various traffic-derived pollutants--whether gaseous or particle-bound--was the same. Such information can be useful for the purposes of managing pollutants in urban areas. Copyright © 2014 Elsevier Ltd. All rights reserved.

Road pricing, air pollution and external costs; Road pricing, luftforurening og eksternalitetsomkostninger

Energy Technology Data Exchange (ETDEWEB)

Solvang Jensen, S.; Ketzel, M. (Aarhus Univ., Danmarks Miljoeundersoegelser, Afd. for Atmosfaerisk Miljoe, Roskilde (Denmark)); Skou Andersen, M. (Aarhus Univ., Danmarks Miljoeundersoegelser, Afd. for Systemanalyse, Roskilde (Denmark))

2010-06-15

The objective of this assessment is to improve the foundation for decision-making about introduction of a road pricing system that aims to reduce the health impacts and social costs of traffic-related air pollution. The analysis focuses on how road emissions, air quality, population exposure, and social costs of air pollution depend on geography (different city sizes and rural areas) and time of the day (rush hours versus non-rush hours). A review of Danish studies related to road pricing has also been carried out to assess the expected effect of road pricing on traffic performance (km travelled), vehicle composition and speed that are factors affecting air pollution. (LN)

A national-scale review of air pollutant concentrations measured in the U.S. near-road monitoring network during 2014 and 2015

Science.gov (United States)

DeWinter, Jennifer L.; Brown, Steven G.; Seagram, Annie F.; Landsberg, Karin; Eisinger, Douglas S.

2018-06-01

In 2010, the U.S. Environmental Protection Agency (EPA) revised the National Ambient Air Quality Standards (NAAQS) for NO2 to include a primary health-based standard for hourly NO2, and required air quality monitoring next to major roadways in urban areas in the U.S. Requirements for near-road measurements also include carbon monoxide (CO) and particulate matter smaller than 2.5 μm in diameter (PM2.5). We performed a national-scale assessment of air pollutants measured at 81 sites in the near-road environment during the first two years (2014 and 2015) of the new measurement program. We evaluated how concentrations at these locations compared to the NAAQS, to concentrations measured at other sites within the same urban areas, and when considering their site characteristics (distance of monitor to road, traffic volume, and meteorology). We also estimated the contribution of emissions from adjacent roadways at each near-road site to the PM2.5 concentrations above the local urban background concentrations, i.e., the near-road "increment." Hourly values of CO reached a maximum of 4.8 ppm across 31 sites in 2014 and 9.6 ppm across 47 sites in 2015, and were well below the NAAQS levels for both the 1-hr (35 ppm) and 8-hr (9 ppm) standards. Hourly concentrations of near-road NO2 reached 258 ppb across 40 sites in 2014; however, there were only two occurrences of a daily 1-hr maximum NO2 concentration above 100 ppb (the level of the hourly NO2 standard). In 2015, hourly concentrations of near-road NO2, monitored at 61 sites in 55 urban areas, reached 154 ppb. Only 0.0015% (n = 5) of hourly NO2 observations in 2015 exceeded 100 ppb. The highest annual NO2 average recorded in 2015 (29.9 ppb) occurred at the Ontario site located along I-10 in the Los Angeles, California, area and was below the level of the NO2 annual standard (53 ppb); in 2014, the highest annual mean NO2 was also observed in Los Angeles at the Anaheim site (27.1 ppb). In 2014, sites in Cincinnati

Impacts of Traffic Tidal Flow on Pollutant Dispersion in a Non-Uniform Urban Street Canyon

Directory of Open Access Journals (Sweden)

Tingzhen Ming

2018-02-01

Full Text Available A three-dimensional geometrical model was established based on a section of street canyons in the 2nd Ring Road of Wuhan, China, and a mathematical model describing the fluid flow and pollutant dispersion characteristics in the street canyon was developed. The effect of traffic tidal flow was investigated based on the measurement results of the passing vehicles as the pollution source of the CFD method and on the spatial distribution of pollutants under various ambient crosswinds. Numerical investigation results indicated that: (i in this three-dimensional asymmetrical shallow street canyon, if the pollution source followed a non-uniform distribution due to the traffic tidal flow and the wind flow was perpendicular to the street, a leeward side source intensity stronger than the windward side intensity would cause an expansion of the pollution space even if the total source in the street is equal. When the ambient wind speed is 3 m/s, the pollutant source intensity near the leeward side that is stronger than that near the windward side (R = 2, R = 3, and R = 5 leads to an increased average concentration of CO at pedestrian breathing height by 26%, 37%, and 41%, respectively. (R is the ratio parameter of the left side pollution source and the right side pollution source; (ii However, this feature will become less significant with increasing wind speeds and changes of wind direction; (iii the pollution source intensity exerted a decisive influence on the pollutant level in the street canyon. With the decrease of the pollution source intensity, the pollutant concentration decreased proportionally.

A Modeling Framework for Improved Characterization of Near-Road Exposure at Fine Scales

Science.gov (United States)

Traffic-related air pollutants could cause adverse health impact to communities near roadways. To estimate the population risk and locate "hotspots" in the near-road environment, quantifying the exposure at a fine spatial resolution is essential. A new state-of-the-art ...

Reduction of Air Pollution Levels Downwind of a Road with an Upwind Noise Barrier

Science.gov (United States)

We propose a dispersion model to characterize the impact of an upwind solid noise barrier next to a highway on air pollution concentrations downwind of the road. The model is based on data from wind tunnel experiments conducted by Heist et al. (2009). The model assumes that the...

Spatial resolution requirements for traffic-related air pollutant exposure evaluations

Science.gov (United States)

Batterman, Stuart; Chambliss, Sarah; Isakov, Vlad

2014-09-01

Vehicle emissions represent one of the most important air pollution sources in most urban areas, and elevated concentrations of pollutants found near major roads have been associated with many adverse health impacts. To understand these impacts, exposure estimates should reflect the spatial and temporal patterns observed for traffic-related air pollutants. This paper evaluates the spatial resolution and zonal systems required to estimate accurately intraurban and near-road exposures of traffic-related air pollutants. The analyses use the detailed information assembled for a large (800 km2) area centered on Detroit, Michigan, USA. Concentrations of nitrogen oxides (NOx) due to vehicle emissions were estimated using hourly traffic volumes and speeds on 9700 links representing all but minor roads in the city, the MOVES2010 emission model, the RLINE dispersion model, local meteorological data, a temporal resolution of 1 h, and spatial resolution as low as 10 m. Model estimates were joined with the corresponding shape files to estimate residential exposures for 700,000 individuals at property parcel, census block, census tract, and ZIP code levels. We evaluate joining methods, the spatial resolution needed to meet specific error criteria, and the extent of exposure misclassification. To portray traffic-related air pollutant exposure, raster or inverse distance-weighted interpolations are superior to nearest neighbor approaches, and interpolations between receptors and points of interest should not exceed about 40 m near major roads, and 100 m at larger distances. For census tracts and ZIP codes, average exposures are overestimated since few individuals live very near major roads, the range of concentrations is compressed, most exposures are misclassified, and high concentrations near roads are entirely omitted. While smaller zones improve performance considerably, even block-level data can misclassify many individuals. To estimate exposures and impacts of traffic

Tracer Studies to Characterize the Effects of Roadside Noise Barriers on Near-Road Pollutant Dispersion under Varying Atmospheric Stability Conditions

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A roadway toxics dispersion study was conducted by the Field Research Division (FRD) of NOAA at the Idaho National Laboratory (INL) near Idaho Falls, ID to document the effects on concentrations of roadway emissions behind a roadside sound barrier in various conditions of atmosph...

Living Near Major Traffic Roads and Risk of Deep Vein Thrombosis

Science.gov (United States)

Baccarelli, Andrea; Martinelli, Ida; Pegoraro, Valeria; Melly, Steven; Grillo, Paolo; Zanobetti, Antonella; Hou, Lifang; Bertazzi, Pier Alberto; Mannucci, Pier Mannuccio; Schwartz, Joel

2010-01-01

Background Particulate air pollution has been consistently linked to increased risk of arterial cardiovascular disease. Few data on air pollution exposure and risk of venous thrombosis are available. We investigated whether living near major traffic roads increases the risk of deep vein thrombosis (DVT), using distance from roads as a proxy for traffic exposure. Methods and Results Between 1995-2005, we examined 663 patients with DVT of the lower limbs and 859 age-matched controls from cities with population>15,000 inhabitants in Lombardia Region, Italy. We assessed distance from residential addresses to the nearest major traffic road using geographic information system methodology. The risk of DVT was estimated from logistic regression models adjusting for multiple clinical and environmental covariates. The risk of DVT was increased (Odds Ratio [OR]=1.33; 95% CI 1.03-1.71; p=0.03 in age-adjusted models; OR=1.47; 95%CI 1.10-1.96; p=0.008 in models adjusted for multiple covariates) for subjects living near a major traffic road (3 meters, 10th centile of the distance distribution) compared to those living farther away (reference distance of 245 meters, 90th centile). The increase in DVT risk was approximately linear over the observed distance range (from 718 to 0 meters), and was not modified after adjusting for background levels of particulate matter (OR=1.47; 95%CI 1.11-1.96; p=0.008 for 10th vs. 90th distance centile in models adjusting for area levels of particulate matter roads is associated with increased risk of DVT. PMID:19506111

A CFD study on the effectiveness of trees to disperse road traffic emissions at a city scale

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Jeanjean, A. P. R.; Hinchliffe, G.; McMullan, W. A.; Monks, P. S.; Leigh, R. J.

2015-11-01

This paper focuses on the effectiveness of trees at dispersing road traffic emissions on a city scale. CFD simulations of air-pollutant concentrations were performed using the OpenFOAM software platform using the k-ε model. Results were validated against the CODASC wind tunnel database before being applied to a LIDAR database of buildings and trees representing the City of Leicester (UK). Most other CFD models in the literature typically use idealised buildings to model wind flow and pollution dispersion. However, the methodology used in this study uses real buildings and trees data from LIDAR to reconstruct a 3D representation of Leicester City Centre. It focuses on a 2 × 2 km area which is on a scale larger than those usually used in other CFD studies. Furthermore, the primary focus of this study is on the interaction of trees with wind flow dynamics. It was found that in effect, trees have a regionally beneficial impact on road traffic emissions by increasing turbulence and reducing ambient concentrations of road traffic emissions by 7% at pedestrian height on average. This was an important result given that previous studies generally concluded that trees trapped pollution by obstructing wind flow in street canyons. Therefore, this study is novel both in its methodology and subsequent results, highlighting the importance of combining local and regional scale models for assessing the impact of trees in urban planning.

Mobile assessment of on-road air pollution and its sources along the East-West Highway in Bhutan

Science.gov (United States)

Wangchuk, Tenzin; Knibbs, Luke D.; He, Congrong; Morawska, Lidia

2015-10-01

Human exposures in transportation microenvironments are poorly represented by ambient stationary monitoring. A number of on-road studies using vehicle-based mobile monitoring have been conducted to address this. Most previous studies were conducted on urban roads in developed countries where the primary emission source was vehicles. Few studies have examined on-road pollution in developing countries in urban settings. Currently, no study has been conducted for roadways in rural environments where a substantial proportion of the population live. This study aimed to characterize on-road air quality on the East-West Highway (EWH) in Bhutan and identify its principal sources. We conducted six mobile measurements of PM10, particle number (PN) count and CO along the entire 570 km length of the EWH. We divided the EWH into five segments, R1-R5, taking the road length between two district towns as a single road segment. The pollutant concentrations varied widely along the different road segments, with the highest concentrations for R5 compared with other road segments (PM10 = 149 μg/m3, PN = 5.74 × 104 particles/cm-3, CO = 0.19 ppm), which is the final segment of the road to the capital. Apart from vehicle emissions, the dominant sources were road works, unpaved roads and roadside combustion activities. Overall, the highest contributions above the background levels were made by unpaved roads for PM10 (6 times background), and vehicle emissions for PN and CO (5 and 15 times background, respectively). Notwithstanding the differences in instrumentation used and particle size range measured, the current study showed lower PN concentrations compared with similar on-road studies. However, concentrations were still high enough that commuters, road maintenance workers and residents living along the EWH, were potentially exposed to elevated pollutant concentrations from combustion and non-combustion sources. Future studies should focus on assessing the dispersion patterns of

On - road mobile source pollutant emissions : identifying hotspots and ranking roads.

Science.gov (United States)

2010-12-30

A considerable amount of pollution to the air in the forms of hydrocarbons, carbon : monoxide (CO), nitrogen oxides (NOx), particulate matter (PM) and air toxics comes : from the on-road mobile sources. Estimation of the emissions of these pollutants...

Simulating the production and dispersion of environmental pollutants in aerosol phase in an urban area of great historical and cultural value.

Science.gov (United States)

Librando, Vito; Tringali, Giuseppe; Calastrini, Francesca; Gualtieri, Giovanni

2009-11-01

Mathematical models were developed to simulate the production and dispersion of aerosol phase atmospheric pollutants which are the main cause of the deterioration of monuments of great historical and cultural value. This work focuses on Particulate Matter (PM) considered the primary cause of monument darkening. Road traffic is the greatest contributor to PM in urban areas. Specific emission and dispersion models were used to study typical urban configurations. The area selected for this study was the city of Florence, a suitable test bench considering the magnitude of architectural heritage together with the remarkable effect of the PM pollution from road traffic. The COPERT model, to calculate emissions, and the street canyon model coupled with the CALINE model, to simulate pollutant dispersion, were used. The PM concentrations estimated by the models were compared to actual PM concentration measurements, as well as related to the trend of some meteorological variables. The results obtained may be defined as very encouraging even the models correlated poorly: the estimated concentration trends as daily averages moderately reproduce the same trends of the measured values.

Synthesis report: program ecosystems, transport, pollutions, 1998 - 2001; Rapport de synthese: programme ecosystemes, transport, pollutions, 1998 - 2001

Energy Technology Data Exchange (ETDEWEB)

Etchelecou, A; Deletraz, G; Elichegaray, Ch

2001-04-01

The ''Ecosystems, Transports, Pollution Program'' ETP Program, has been elaborated to evaluate the road pollution impacts on the mountain ecosystems. Four mountains valleys have been chosen: two in Alps (Chamonix and Maurienne) and two in Pyrenees (Biriatou and Vallee d'Aspe). This Program presents six objectives: the road traffic characterization, the pollutants emission estimation, the pollutants concentrations in the air, the pollutants dispersion according to relief, the relationships between pollutants emissions and bio-monitoring, the road pollution effects on nearby ecosystems. (A.L.B.)

Synthesis report: program ecosystems, transport, pollutions, 1998 - 2001; Rapport de synthese: programme ecosystemes, transport, pollutions, 1998 - 2001

Energy Technology Data Exchange (ETDEWEB)

Etchelecou, A.; Deletraz, G.; Elichegaray, Ch

2001-04-01

The ''Ecosystems, Transports, Pollution Program'' ETP Program, has been elaborated to evaluate the road pollution impacts on the mountain ecosystems. Four mountains valleys have been chosen: two in Alps (Chamonix and Maurienne) and two in Pyrenees (Biriatou and Vallee d'Aspe). This Program presents six objectives: the road traffic characterization, the pollutants emission estimation, the pollutants concentrations in the air, the pollutants dispersion according to relief, the relationships between pollutants emissions and bio-monitoring, the road pollution effects on nearby ecosystems. (A.L.B.)

Near-Roadway Pollution and Childhood Asthma: Implications for Developing “Win–Win” Compact Urban Development and Clean Vehicle Strategies

Science.gov (United States)

Perez, Laura; Lurmann, Fred; Wilson, John; Pastor, Manuel; Brandt, Sylvia J.; Künzli, Nino

2012-01-01

Background: The emerging consensus that exposure to near-roadway traffic-related pollution causes asthma has implications for compact urban development policies designed to reduce driving and greenhouse gases. Objectives: We estimated the current burden of childhood asthma-related disease attributable to near-roadway and regional air pollution in Los Angeles County (LAC) and the potential health impact of regional pollution reduction associated with changes in population along major traffic corridors. Methods: The burden of asthma attributable to the dual effects of near-roadway and regional air pollution was estimated, using nitrogen dioxide and ozone as markers of urban combustion-related and secondary oxidant pollution, respectively. We also estimated the impact of alternative scenarios that assumed a 20% reduction in regional pollution in combination with a 3.6% reduction or 3.6% increase in the proportion of the total population living near major roads, a proxy for near-roadway exposure. Results: We estimated that 27,100 cases of childhood asthma (8% of total) in LAC were at least partly attributable to pollution associated with residential location within 75 m of a major road. As a result, a substantial proportion of asthma-related morbidity is a consequence of near-roadway pollution, even if symptoms are triggered by other factors. Benefits resulting from a 20% regional pollution reduction varied markedly depending on the associated change in near-roadway proximity. Conclusions: Our findings suggest that there are large and previously unappreciated public health consequences of air pollution in LAC and probably in other metropolitan areas with dense traffic corridors. To maximize health benefits, compact urban development strategies should be coupled with policies to reduce near-roadway pollution exposure. PMID:23008270

Modelling Air Pollution Near Arterial Roads and Highways

Science.gov (United States)

Shenouda, Deloor Abdel Shaheed

In this study emissions of carbon dioxide (CO _2), carbon monoxide (CO), hydrocarbons (HC) and nitrogen oxides (NO_{rm x}) from vehicles are modelled by considering the instantaneous power generated by each vehicle and modifying the expressions developed by Post et al, (1981). The emissions from both spark ignition (SI) and diesel vehicles have been included. The model was used to estimate fuel consumption and emissions over a standard driving cycle. When used for spark ignition vehicles over a driving cycle, the influence of cold starts was quantified and allowance was made, in the case of equipped vehicles, for catalyst warm-up and for variations in catalyst efficiency. The model was validated against fuel consumption and emissions data obtained using ADR27 and ADR37 tests, and also against detailed, high time resolution analysis of ADR27 tests carried out by the Victorian EPA. The emissions model was used in conjunction with two pollution dispersion models viz: HIWAY and CALINE to compare predicted concentrations with an experimental data -set consisting of measurements of the pollutants of CO _2, CO, HC, and NO_ {rm x}, and were made under a variety of traffic and meteorological conditions. The measurements were made at locations up to 60 metres downwind from the roadside and to heights of 10m above the ground. A video camera was used to record the traffic flow, speed and type (classified simply as domestic, light or heavy commercial). The emission rates of CO, HC, and NO_ {rm x} (at slope 0^ circ) for spark ignition and diesel vehicles produced by the power-based emissions model were found to be similar to those produced by the California EPA, EMFAC7, emissions model.

Dispersion and transport of atmospheric pollutants

International Nuclear Information System (INIS)

Cieslik, S.

1991-01-01

This paper presents the physical mechanisms that govern the dispersion and transport of air pollutant; the influence of the state of the 'carrying fluid', i.e. the role of meteorology; and finally, outlines the different techniques of assessing the process. Aspects of physical mechanisms and meteorology covered include: fate of an air pollutant; turbulence and dispersion; transport; wind speed and direction; atmospheric stability; and the role of atmospheric water. Assessment techniques covered are: concentrations measurements; modelling meteorological observations; and tracer releases. It is concluded that the only way to reduce air pollution is to pollute less. 10 refs., 12 figs., 2 tabs

Near-Source Modeling Updates: Building Downwash & Near-Road

Science.gov (United States)

The presentation describes recent research efforts in near-source model development focusing on building downwash and near-road barriers. The building downwash section summarizes a recent wind tunnel study, ongoing computational fluid dynamics simulations and efforts to improve ...

Synthesis report: program ecosystems, transport, pollutions, 1998 - 2001

International Nuclear Information System (INIS)

Etchelecou, A.; Deletraz, G.; Elichegaray, Ch.

2001-04-01

The ''Ecosystems, Transports, Pollution Program'' ETP Program, has been elaborated to evaluate the road pollution impacts on the mountain ecosystems. Four mountains valleys have been chosen: two in Alps (Chamonix and Maurienne) and two in Pyrenees (Biriatou and Vallee d'Aspe). This Program presents six objectives: the road traffic characterization, the pollutants emission estimation, the pollutants concentrations in the air, the pollutants dispersion according to relief, the relationships between pollutants emissions and bio-monitoring, the road pollution effects on nearby ecosystems. (A.L.B.)

Effects of Fetch on Turbulent Flow and Pollutant Dispersion Within a Cubical Canopy

Science.gov (United States)

Michioka, Takenobu; Takimoto, Hiroshi; Ono, Hiroki; Sato, Ayumu

2018-03-01

The effects of fetch on turbulent flow and pollutant dispersion within a canopy formed by regularly-spaced cubical objects is investigated using large-eddy simulation. Six tracer gases are simultaneously released from a ground-level continuous pollutant line source placed parallel to the spanwise axis at the first, second, third, fifth, seventh and tenth rows. Beyond the seventh row, the standard deviations of the fluctuations in the velocity components and the Reynolds shear stresses reach nearly equivalent states. Low-frequency turbulent flow is generated near the bottom surface around the first row and develops as the fetch increases. The turbulent flow eventually passes through the canopy at a near-constant interval. The mean concentration within the canopy reaches a near-constant value beyond the seventh row. In the first and second rows, narrow coherent structures frequently affect the pollutant escape from the top of the canopy. These structures increase in width as the fetch increases, and they mainly affect the removal of pollutants from the canopy.

Monitoring Gaseous and Particulate Air Pollutants near Major ...

African Journals Online (AJOL)

High traffic volume and traffic congestion on Nigerian roads have led to increase in the concentration of pollutants in the air t posing health risks for human population. This study investigates air quality due to vehicular emissions in some busy roads in Abeokuta metropolis, Nigeria. Air pollutants such as CO, CO2, NO, NO2, ...

Pollution level assessment of road dust from islamabad expressway

International Nuclear Information System (INIS)

Faiz, Y.; Siddiqui, N.

2013-01-01

Thirteen road dust and four soil samples were analyzed using Instrumental Neutron Activation Analysis (INAA) and Flame Atomic Absorption Spectroscopy (FAAS) to determine the elemental composition of road dust collected from Islamabad Expressway. Pollution parameters and indicators such as Enrichment Factors (EFs), Pollution Load Index (PLI), Geoaccumulation Index (I G eo), Pollution Index (PI) and Integrated Pollution Index (IPI) were calculated and showed that the area around Islamabad Expressway is low to moderately polluted especially by elements such as Mg and Sb. The IPI of the elements was found to vary in the order; Mg>Sb>Cu>Sr ≅Pb>Ga>Na >Sn≅ Zn>Yb>Se>Hf. The 5 samples collected around the busy intersections of Faizabad and Zero Point have higher amounts of most of the elements determined. Moreover the pollution indices for these samples indicate that these sites are more contaminated than the remaining 8 sampling sites. (author)

AIR POLLUTION FROM TRAFFIC AND RESPIRATORY HEALTH

Directory of Open Access Journals (Sweden)

Maja Nikolić

2004-12-01

Full Text Available Air pollution has very important influence on human health. Earlier investigations were not employed with estimation of influence of air pollution, which spring from traffic, on people health who live near busy cross – road.The aim of this paper was to determine how living near busy cross – road influences on appearance of respiratory symptoms and illness.400 adult people between 18-76 age who live five year least on this location at took a part in investigation. One group (200 live in Nis near the busiest cross-road, another group live in Niska Banja near cross-road with the smallest concentration of pollutants in last five years.We have determined that examines, who live near busy cross – road had statistical signify greater prevalence of all respiratory symptoms and pneumonia.Our investigation showed that living near busy cross road present risk factor for appearance of respiratory symptoms and pneumonia.

Study on road surface source pollution controlled by permeable pavement

Science.gov (United States)

Zheng, Chaocheng

2018-06-01

The increase of impermeable pavement in urban construction not only increases the runoff of the pavement, but also produces a large number of Non-Point Source Pollution. In the process of controlling road surface runoff by permeable pavement, a large number of particulate matter will be withheld when rainwater is being infiltrated, so as to control the source pollution at the source. In this experiment, we determined the effect of permeable road surface to remove heavy pollutants in the laboratory and discussed the related factors that affect the non-point pollution of permeable pavement, so as to provide a theoretical basis for the application of permeable pavement.

On the pollutant removal, dispersion, and entrainment over two-dimensional idealized street canyons

Science.gov (United States)

Liu, Chun-Ho; Wong, Colman C. C.

2014-01-01

Pollutant dispersion over urban areas is not that well understood, in particular at the street canyon scale. This study is therefore conceived to examine how urban morphology modifies the pollutant removal, dispersion, and entrainment over urban areas. An idealized computational domain consisting of 12 two-dimensional (2D) identical street canyons of unity aspect ratio is employed. The large-eddy simulation (LES) is used to calculate the turbulent flows and pollutant transport in the urban boundary layer (UBL). An area source of uniform pollutant concentration is applied on the ground of the first street canyon. A close examination on the roof-level turbulence reveals patches of low-speed air masses in the streamwise flows and narrow high-speed downdrafts in the shear layer. Different from the flows over a smooth surface, the turbulence intensities are peaked near the top of the building roughness. The pollutant is rather uniformly distributed inside a street canyon but disperses quickly in the UBL over the buildings. Partitioning the vertical pollutant flux into its mean and turbulent components demystifies that the pollutant removal is mainly governed by turbulence. Whereas, mean wind carries pollutant into and out of a street canyon simultaneously. In addition to wind speed promotion, turbulent mixing is thus required to dilute the ground-level pollutants, which are then removed from the street canyon to the UBL. Atmospheric flows slow down rapidly after the leeward buildings, leading to updrafts carrying pollutants away from the street canyons (the basic pollutant removal mechanism).

Numerical simulation on pollutant dispersion from vehicle exhaust in street configurations.

Science.gov (United States)

Yassin, Mohamed F; Kellnerová, R; Janour, Z

2009-09-01

The impact of the street configurations on pollutants dispersion from vehicles exhausts within urban canyons was numerically investigated using a computational fluid dynamics (CFD) model. Three-dimensional flow and dispersion of gaseous pollutants were modeled using standard kappa - epsilon turbulence model, which was numerically solved based on Reynolds-averaged Navier-Stokes equations by the commercial CFD code FLUENT. The concentration fields in the urban canyons were examined in three cases of street configurations: (1) a regular-shaped intersection, (2) a T-shaped intersection and (3) a Skew-shaped crossing intersection. Vehicle emissions were simulated as double line sources along the street. The numerical model was validated against wind tunnel results in order to optimize the turbulence model. Numerical predictions agreed reasonably well with wind tunnel results. The results obtained indicate that the mean horizontal velocity was very small in the center near the lower region of street canyon. The lowest turbulent kinetic energy was found at the separation and reattachment points associated with the corner of the down part of the upwind and downwind buildings in the street canyon. The pollutant concentration at the upwind side in the regular-shaped street intersection was higher than that in the T-shaped and Skew-shaped street intersections. Moreover, the results reveal that the street intersections are important factors to predict the flow patterns and pollutant dispersion in street canyon.

On the use of numerical modelling for near-field pollutant dispersion in urban environments − A review

International Nuclear Information System (INIS)

Lateb, M.; Meroney, R.N.; Yataghene, M.; Fellouah, H.; Saleh, F.; Boufadel, M.C.

2016-01-01

This article deals with the state-of-the-art of experimental and numerical studies carried out regarding air pollutant dispersion in urban environments. Since the simulation of the dispersion field around buildings depends strongly on the correct simulation of the wind-flow structure, the studies performed during the past years on the wind-flow field around buildings are reviewed. This work also identifies errors that can produce poor results when numerically modelling wind flow and dispersion fields around buildings in urban environments. Finally, particular attention is paid to the practical guidelines developed by researchers to establish a common methodology for verification and validation of numerical simulations and/or to assist and support the users for a better implementation of the computational fluid dynamics (CFD) approach. - This review article enlightens the reader on the use of CFD for pollutant dispersion. Errors that induce poor results and critical parameters that compromise significantly the accuracy and reliability are identified.

Application of magnetic, geochemical and micro-morphological methods in environmental studies of urban pollution generated by road traffic

Energy Technology Data Exchange (ETDEWEB)

Bucko, M.

2012-11-01

Road traffic is at present one of the major sources of environmental pollution in urban areas. Magnetic particles, heavy metals and other compounds generated by traffic can greatly affect ambient air quality and have direct implications for human health. The general aim of this research was to identify and characterize magnetic vehicle-derived particulates using magnetic, geochemical and micro-morphological methods. A combination of three different methods was used to discriminate sources of particular anthropogenic particles. Special emphasis was placed on the application of various collectors (roadside soil, snow, lichens and moss bags) to monitor spatial and temporal distribution of traffic pollution on roadsides. The spatial distribution of magnetic parameters of road dust accumulated in roadside soil, snow, lichens and moss bags indicates that the highest concentration of magnetic particles is in the sampling points situated closest to the road edge. The concentration of magnetic particles decreases with increasing distance from the road indicating vehicle traffic as a major source of emission. Significant differences in horizontal distribution of magnetic susceptibility were observed between soil and snow. Magnetic particles derived from road traffic deposit on soil within a few meters from the road, but on snow up to 60 m from the road. The values of magnetic susceptibility of road dust deposited near busy urban motorway are significantly higher than in the case of low traffic road. These differences are attributed to traffic volume, which is 30 times higher on motorway than on local road. Moss bags placed at the edge of urban parks situated near major roads show higher values of magnetic susceptibility than moss bags from parks located near minor routes. Enhanced concentrations of heavy metals (e.g. Fe, Mn, Zn, Cu, Cr, Ni and Co) were observed in the studied samples. This may be associated with specific sources of vehicle emissions (e.g. exhaust and non

Macroeconomic analysis of road vehicles related environmental pollution in Hungary

Science.gov (United States)

Török, Árpád; Török, Ádám

2014-06-01

The article aims to examine the relationship between road transport and macro economy, especially the use of fossil energy in transport sector. Nowadays environmental pollution is a key issue on the EU level as well as in Hungary. Lots of effort have been already done in order to decrease emissions in road transport, but a lot more need to be done. The article aims to prove that the only possible solution is technological innovation in order to reach emission reduction target without decline of the GDP. The basic idea is to ensure sustainable development, to decrease environmental pollution in road transport without harming the economy. In the EU and in Hungary road vehicles are powered by fossil fuelled internal combustion engines. This paper aims to analyse the role of the fossil fuel-based road transport sector within the economy with the usage of constant elasticity substitution (CES) production functions. Authors have built CES production function for Hungary. Parameters were calculated based on the validated model.

Road traffic noise, air pollution components and cardiovascular events

NARCIS (Netherlands)

Kluizenaar, Y. de; Lenthe, F.J. van; Visschedijk, A.J.H.; Zandveld, P.Y.J; Miedema, H.M.E.; Mackenbach, J.P.

2013-01-01

Traffic noise and air pollution have been associated with cardiovascular health effects. Until date, only a limited amount of prospective epidemiological studies is available on long-term effects of road traffic noise and combustion related air pollution. This study investigates the relationship

Exposure to long-term air pollution and road traffic noise in relation to cholesterol: A cross-sectional study.

Science.gov (United States)

Sørensen, Mette; Hjortebjerg, Dorrit; Eriksen, Kirsten T; Ketzel, Matthias; Tjønneland, Anne; Overvad, Kim; Raaschou-Nielsen, Ole

2015-12-01

Exposure to traffic noise and air pollution have both been associated with cardiovascular disease, though the mechanisms behind are not yet clear. We aimed to investigate whether the two exposures were associated with levels of cholesterol in a cross-sectional design. In 1993–1997, 39,863 participants aged 50–64 year and living in the Greater Copenhagen area were enrolled in a population-based cohort study. For each participant, non-fasting total cholesterol was determined in whole blood samples on the day of enrolment. Residential addresses 5-years preceding enrolment were identified in a national register and road traffic noise (Lden) were modeled for all addresses. For air pollution, nitrogen dioxide (NO2) was modeled at all addresses using a dispersion model and PM2.5 was modeled at all enrolment addresses using a land-use regression model. Analyses were done using linear regression with adjustment for potential confounders as well as mutual adjustment for the three exposures. Baseline residential exposure to the interquartile range of road traffic noise,NO2 and PM2.5 was associated with a 0.58 mg/dl (95% confidence interval: −0.09; 1.25), a 0.68 mg/dl (0.22; 1.16) and a 0.78 mg/dl (0.22; 1.34) higher level of total cholesterol in single pollutant models, respectively. In two pollutant models with adjustment for noise in air pollution models and vice versa, the association between air pollution and cholesterol remained for both air pollution variables (NO2: 0.72 (0.11; 1.34); PM2.5: 0.70 (0.12; 1.28) mg/dl), whereas there was no association for noise (−0.08mg/dl). In three-pollutant models (NO2, PM2.5 and road traffic noise), estimates for NO2 and PM2.5 were slightly diminished (NO2: 0.58 (−0.05; 1.22); PM2.5: 0.57 (−0.02; 1.17) mg/dl). Air pollution and possibly also road traffic noise may be associated with slightly higher levels of cholesterol, though associations for the two exposures were difficult to separate.

Impact of noise barriers on the dispersal of solid pollutants from car emissions and their deposition in soil

Directory of Open Access Journals (Sweden)

Wawer Małgorzata

2017-03-01

Full Text Available Despite the existence of various methods aimed at protecting the environment from the negative influence of roads, there is a lack of adequate techniques for monitoring and reducing the spread of roadside pollution into the air and soils. The aim of this study was to assess the impact of noise barriers (sound walls on the dispersal and soil deposition of solid pollutants from car emissions, based on both quantitative and qualitative analysis. Magnetic susceptibility measurements, trace elements analyses, and platinum (Pt and rhodium (Rh content determinations were performed on soil samples collected in the vicinity of various types of noise barrier. Previous investigations have shown that most traffic emissions are deposited in the close vicinity of roads (up to 10 m, with pollution levels decreasing with increasing distance from the road edge. However, the results of the present study indicate that this distribution is disturbed in areas in which noise barriers are located. Moreover, additional soil enrichment with trace elements was observed at approx. 10-15 m behind the barriers. The spatial distribution of trace elements contents in the tested soil samples corresponded to the magnetic susceptibility values. High Fe, Zn, Mn and Pb levels were observed adjacent to noise barriers composed of sawdust concrete and steel panels.

Understanding road surface pollutant wash-off and underlying physical processes using simulated rainfall.

Science.gov (United States)

Egodawatta, Prasanna; Goonetilleke, Ashantha

2008-01-01

Pollutant wash-off is one of the key pollutant processes that detailed knowledge is required in order to develop successful treatment design strategies for urban stormwater. Unfortunately, current knowledge relating to pollutant wash-off is limited. This paper presents the outcomes of a detailed investigation into pollutant wash-off on residential road surfaces. The investigations consisted of research methodologies formulated to overcome the physical constraints due to the heterogeneity of urban paved surfaces and the dependency on naturally occurring rainfall. This entailed the use of small road surface plots and artificially simulated rainfall. Road surfaces were selected due to its critical importance as an urban stormwater pollutant source. The study results showed that the influence of initially available pollutants on the wash-off process was limited. Furthermore, pollutant wash-off from road surfaces can be replicated using an exponential equation. However, the typical version of the exponential wash-off equation needs to be modified by introducing a non dimensional factor referred to as 'capacity factor' CF. Three rainfall intensity ranges were identified where the variation of CF can be defined. Furthermore, it was found that particulate density rather than size is the critical parameter that influences the process of pollutant wash-off. (c) IWA Publishing 2008.

Road traffic and cardiovascular health effects - Road traffic noise and air pollution

NARCIS (Netherlands)

Kluizenaar, Y. de; Miedema, H.M.E.

2009-01-01

Exposure to both environmental noise and air pollution has been associated with cardiovascular health effects. Until now, few studies have considered both stressors simultaneously. Two large studies were carried out investigating the relationship between road traffic noise and several cardiovascular

Road traffic noise, air pollution components and cardiovascular events.

Science.gov (United States)

de Kluizenaar, Yvonne; van Lenthe, Frank J; Visschedijk, Antoon J H; Zandveld, Peter Y J; Miedema, Henk M E; Mackenbach, Johan P

2013-01-01

Traffic noise and air pollution have been associated with cardiovascular health effects. Until date, only a limited amount of prospective epidemiological studies is available on long-term effects of road traffic noise and combustion related air pollution. This study investigates the relationship between road traffic noise and air pollution and hospital admissions for ischemic heart disease (IHD: International Classification of Diseases (ICD9) 410-414) or cerebrovascular disease (cerebrovascular event [CVE]: ICD9 430-438). We linked baseline questionnaire data to 13 years of follow-up on hospital admissions and road traffic noise and air pollution exposure, for a large random sample (N = 18,213) of inhabitants of the Eindhoven region, Netherlands. Subjects with cardiovascular event during follow-up on average had higher road traffic noise day, evening, night level (L den) and air pollution exposure at the home. After adjustment for confounders (age, sex, body mass index, smoking, education, exercise, marital status, alcohol use, work situation, financial difficulties), increased exposure did not exert a significant increased risk of hospital admission for IHD or cerebrovascular disease. Relative risks (RRs) for a 5 (th) to 95 (th) percentile interval increase were 1.03 (0.88-1.20) for L den; 1.04 (0.90-1.21) for particulate matter (PM 10 ); 1.05 (0.91-1.20) for elemental carbon (EC); and 1.12 (096-1.32) for nitrogen dioxide (NO 2 ) in the full model. While the risk estimate seemed highest for NO 2 , for a 5 (th) to 95 (th) percentile interval increase, expressed as RRs per 1 μg/m 3 increases, hazard ratios seemed highest for EC (RR 1.04 [0.92-1.18]). In the subgroup of study participants with a history of cardiovascular disease, RR estimates seemed highest for noise exposure (1.19 [0.87-1.64] for L den); in the subgroup of elderly RR seemed highest for air pollution exposure (RR 1.24 [0.93-1.66] for NO 2 ).

A Numerical Study on Characteristics of Flow and Reactive Pollutant Dispersion in Step‒up Street Canyons

Science.gov (United States)

Kim, E. R.; Kim, J.

2014-12-01

For decades, many metro‒ and/or mega‒cities have grown and densities of population and building have increased. Because pollutants released from sources near ground surface such as vehicles are not easy to escape from street canyons which are spaces between buildings standing along streets pedestrians, drivers and residents are likely to be exposed to high concentrations of hazardous pollutants. Therefore, it is important to understand characteristics of flow and pollutant dispersion in street canyons. In this study, step‒up street canyons with higher downwind buildings are considered for understanding flow and reactive pollutants' dispersion characteristics there as a basic step to understand the characteristics in wider urban areas. This study used a CFD model coupled to a chemistry module. Detailed flow and air pollutant concentration are analyzed in step‒up street canyons with different upwind building heights.

Residential proximity to major roads and term low birth weight: the roles of air pollution, heat, noise, and road-adjacent trees.

Science.gov (United States)

Dadvand, Payam; Ostro, Bart; Figueras, Francesc; Foraster, Maria; Basagaña, Xavier; Valentín, Antònia; Martinez, David; Beelen, Rob; Cirach, Marta; Hoek, Gerard; Jerrett, Michael; Brunekreef, Bert; Nieuwenhuijsen, Mark J

2014-07-01

Maternal residential proximity to roads has been associated with adverse pregnancy outcomes. However, there is no study investigating mediators or buffering effects of road-adjacent trees on this association. We investigated the association between mothers' residential proximity to major roads and term low birth weight (LBW), while exploring possible mediating roles of air pollution (PM(2.5), PM(2.5-10), PM(10), PM(2.5) absorbance, nitrogen dioxide, and nitrogen oxides), heat, and noise and buffering effect of road-adjacent trees on this association. This cohort study was based on 6438 singleton term births in Barcelona, Spain (2001-2005). Road proximity was measured as both continuous distance to and living within 200 m from a major road. We assessed individual exposures to air pollution, noise, and heat using, respectively, temporally adjusted land-use regression models, annual averages of 24-hour noise levels across 50 m and 250 m, and average of satellite-derived land-surface temperature in a 50-m buffer around each residential address. We used vegetation continuous fields to abstract tree coverage in a 200-m buffer around major roads. Living within 200 m of major roads was associated with a 46% increase in term LBW risk; an interquartile range increase in heat exposure with an 18% increase; and third-trimester exposure to PM(2.5), PM(2.5-10), and PM10 with 24%, 25%, and 26% increases, respectively. Air pollution and heat exposures together explained about one-third of the association between residential proximity to major roads and term LBW. Our observations on the buffering of this association by road-adjacent trees were not consistent between our 2 measures of proximity to major roads. An increased risk of term LBW associated with proximity to major roads was partly mediated by air pollution and heat exposures.

Cyclists’ Anger As Determinant of Near Misses Involving Different Road Users

Directory of Open Access Journals (Sweden)

Víctor Marín Puchades

2017-12-01

Full Text Available Road anger constitutes one of the determinant factors related to safety outcomes (e.g., accidents, near misses. Although cyclists are considered vulnerable road users due to their relatively high rate of fatalities in traffic, previous research has solely focused on car drivers, and no study has yet investigated the effect of anger on cyclists’ safety outcomes. The present research aims to investigate, for the first time, the effects of cycling anger toward different types of road users on near misses involving such road users and near misses in general. Using a daily diary web-based questionnaire, we collected data about daily trips, bicycle use, near misses experienced, cyclist’s anger and demographic information from 254 Spanish cyclists. Poisson regression was used to assess the association of cycling anger with near misses, which is a count variable. No relationship was found between general cycling anger and near misses occurrence. Anger toward specific road users had different effects on the probability of near misses with different road users. Anger toward the interaction with car drivers increased the probability of near misses involving cyclists and pedestrians. Anger toward interaction with pedestrians was associated with higher probability of near misses with pedestrians. Anger toward cyclists exerted no effect on the probability of near misses with any road user (i.e., car drivers, cyclists or pedestrians, whereas anger toward the interactions with the police had a diminishing effect on the occurrence of near misses’ involving all types of road users. The present study demonstrated that the effect of road anger on safety outcomes among cyclists is different from that of motorists. Moreover, the target of anger played an important role on safety both for the cyclist and the specific road users. Possible explanations for these differences are based on the difference in status and power with motorists, as well as on the potential

Energy Dispersive X-Ray Fluorescent Analysis of Soil in the Vicinity of Industrial Areas and Heavy Metal Pollution Assessment

Science.gov (United States)

Singh, V.; Joshi, G. C.; Bisht, D.

2017-05-01

The soil of two agricultural sites near an industrial area was investigated for heavy metal pollution using energy dispersive X-ray fluorescence (EDXRF). The concentration values for 17 elements were determined in the soil samples including eight heavy metal elements, i.e., Fe, Ni, As, Pb, Mn, Cr, Cu, and Zn. The soil near a pulp and paper mill was found to be highly polluted by the heavy metals. The concentration data obtained by EDXRF were further examined by calculating the pollution index and Nemerow integrated pollution index.

Effect of real-time boundary wind conditions on the air flow and pollutant dispersion in an urban street canyon—Large eddy simulations

Science.gov (United States)

Zhang, Yun-Wei; Gu, Zhao-Lin; Cheng, Yan; Lee, Shun-Cheng

2011-07-01

Air flow and pollutant dispersion characteristics in an urban street canyon are studied under the real-time boundary conditions. A new scheme for realizing real-time boundary conditions in simulations is proposed, to keep the upper boundary wind conditions consistent with the measured time series of wind data. The air flow structure and its evolution under real-time boundary wind conditions are simulated by using this new scheme. The induced effect of time series of ambient wind conditions on the flow structures inside and above the street canyon is investigated. The flow shows an obvious intermittent feature in the street canyon and the flapping of the shear layer forms near the roof layer under real-time wind conditions, resulting in the expansion or compression of the air mass in the canyon. The simulations of pollutant dispersion show that the pollutants inside and above the street canyon are transported by different dispersion mechanisms, relying on the time series of air flow structures. Large scale air movements in the processes of the air mass expansion or compression in the canyon exhibit obvious effects on pollutant dispersion. The simulations of pollutant dispersion also show that the transport of pollutants from the canyon to the upper air flow is dominated by the shear layer turbulence near the roof level and the expansion or compression of the air mass in street canyon under real-time boundary wind conditions. Especially, the expansion of the air mass, which features the large scale air movement of the air mass, makes more contribution to the pollutant dispersion in this study. Comparisons of simulated results under different boundary wind conditions indicate that real-time boundary wind conditions produces better condition for pollutant dispersion than the artificially-designed steady boundary wind conditions.

Lead pollution of road-side vegetation

Energy Technology Data Exchange (ETDEWEB)

Quinche, J P; Zuber, R; Bovay, E

1969-01-01

In Switzerland, investigations have been made in 1967/1968 concerning the distribution of lead issued from the antiknocking additive of petrol. Observations show that the deposits in meadows in the immediate surrounding (first meter) of roads and highways with high traffic density were especially high (50-100 ppm in dry matter). The pollution is still perceptible even as far as 50 meters from the road. Moreover, during the summer (July and August), a second zone of high lead accumulation (more than 100 ppm) was detected 50 to 100 m from the road, particularly along the highways. This probably is caused by certain climatic conditions and the increase of traffic volume. With regard to fruits, only the downy species (e.g. apricots, peaches) retain some quantities of lead on their skin. Vegetables with large leaves, e.g. lettuce, spinach, and particularly vegetables with definite dissected foliage, such as fennel and parsley, may accumulate relatively high quantities of lead. According to some authors, up to 50 percent of these deposits may be eliminated by washing with water. Conversely, root vegetables (e.g. carrots, onions) do not show a perceptible lead contamination. Likewise the flesh of fruits is not markedly polluted by lead. Trials with foddering milk cows using hay harvested along a highway are not yet analyzed. The results from these trials should permit determining the proportion of lead which remains in the tissues (meat etc.) or passes over into the milk.

Characterizing spatial variability of air pollution from vehicle traffic around the Houston Ship Channel area

Science.gov (United States)

Zhang, Xueying; Craft, Elena; Zhang, Kai

2017-07-01

Mobile emissions are a major source of urban air pollution and have been associated with a variety of adverse health outcomes. The Houston Ship Channel area is the home of a large number of diesel-powered vehicles emitting fine particulate matter (PM2.5; ≤2.5 μm in aerodynamic diameter) and nitrogen oxides (NOx). However, the spatial variability of traffic-related air pollutants in the Houston Ship Channel area has rarely been investigated. The objective of this study is to characterize spatial variability of PM2.5 and NOx concentrations attributable to on-road traffic in the Houston Ship Channel area in the year of 2011. We extracted the road network from the Texas Department of Transportation Road Inventory, and calculated emission rates using the Motor Vehicle Emission Simulator version 2014a (MOVES2014a). These parameters and preprocessed meteorological parameters were entered into a Research LINE-source Dispersion Model (RLINE) to conduct a simulation. Receptors were placed at 50 m resolution within 300 m to major roads and at 150 m resolution in the rest of the area. Our findings include that traffic-related PM2.5 were mainly emitted from trucks, while traffic-related NOx were emitted from both trucks and cars. The traffic contributed 0.90 μg/m3 PM2.5 and 29.23 μg/m3 NOx to the annual average mass concentrations of on-road air pollution, and the concentrations of the two pollutants decreased by nearly 40% within 500 m distance to major roads. The pollution level of traffic-related PM2.5 and NOx was higher in winter than those in the other three seasons. The Houston Ship Channel has earlier morning peak hours and relative late afternoon hours, which indicates the influence of goods movement from port activity. The varied near-road gradients illustrate that proximities to major roads are not an accurate surrogate of traffic-related air pollution.

Assessment of pollution in road runoff using a Bufo viridis biological assay

International Nuclear Information System (INIS)

Dorchin, A.; Shanas, U.

2010-01-01

Road runoff is a major source of environmental pollution, significantly threatening nearby aquatic habitats. Chemical analyses indicate high pollutant concentrations in the road's 'first flush', but bioassays are more advantageous for addressing the cumulative effects of the numerous pollutants within the runoff. We used Bufo viridis embryos and larvae to assess the toxicity of road runoff from two major highways in Israel. We show, for the first time, that exposure to midseason runoff not only has an adverse effect on growth and development rates of B. viridis larvae but can also lead to increased rates of morphological deformations. Seasonal first flushes, despite having higher metal concentrations, did not adversely affect the toad larvae, apparently due to a counter effect of organic matter that potentially served as a supplementary energy resource. Road runoff can be a major cause for a qualitative decrease in the quality of aquatic habitats threatening amphibians in Israel. - Highway runoff has detrimental effects on the development of B. viridis larvae.

Assessment of pollution in road runoff using a Bufo viridis biological assay.

Science.gov (United States)

Dorchin, A; Shanas, U

2010-12-01

Road runoff is a major source of environmental pollution, significantly threatening nearby aquatic habitats. Chemical analyses indicate high pollutant concentrations in the road's "first flush", but bioassays are more advantageous for addressing the cumulative effects of the numerous pollutants within the runoff. We used Bufo viridis embryos and larvae to assess the toxicity of road runoff from two major highways in Israel. We show, for the first time, that exposure to midseason runoff not only has an adverse effect on growth and development rates of B. viridis larvae but can also lead to increased rates of morphological deformations. Seasonal first flushes, despite having higher metal concentrations, did not adversely affect the toad larvae, apparently due to a counter effect of organic matter that potentially served as a supplementary energy resource. Road runoff can be a major cause for a qualitative decrease in the quality of aquatic habitats threatening amphibians in Israel. Copyright © 2010 Elsevier Ltd. All rights reserved.

Combined effects of road traffic noise and ambient air pollution in relation to risk for stroke?

DEFF Research Database (Denmark)

Sørensen, Mette; Lühdorf, Pernille; Ketzel, Matthias

2014-01-01

Exposure to road traffic noise and air pollution have both been associated with risk for stroke. The few studies including both exposures show inconsistent results. We aimed to investigate potential mutual confounding and combined effects between road traffic noise and air pollution in association...... to 2009 were identified in national registers and road traffic noise and air pollution were modeled for all addresses. Analyses were done using Cox regression. A higher mean annual exposure at time of diagnosis of 10µg/m(3) nitrogen dioxide (NO2) and 10dB road traffic noise at the residential address...... was found for combination of high noise and high NO2 (IRR=1.28; 95% CI=1.09-1.52). Fatal stroke was positively associated with air pollution and not with traffic noise. In conclusion, in mutually adjusted models road traffic noise and not air pollution was associated ischemic stroke, while only air...

The measurement of dry deposition and surface runoff to quantify urban road pollution in Taipei, Taiwan.

Science.gov (United States)

Wang, Yunn-Jinn; Chen, Chi-Feng; Lin, Jen-Yang

2013-10-16

Pollutants deposited on road surfaces and distributed in the environment are a source of nonpoint pollution. Field data are traditionally hard to collect from roads because of constant traffic. In this study, in cooperation with the traffic administration, the dry deposition on and road runoff from urban roads was measured in Taipei City and New Taipei City, Taiwan. The results showed that the dry deposition is 2.01-5.14 g/m(2) · day and 78-87% of these solids are in the 75-300 µm size range. The heavy metals in the dry deposited particles are mainly Fe, Zn, and Na, with average concentrations of 34,978, 1,519 and 1,502 ppm, respectively. Elevated express roads show the highest heavy metal concentrations. Not only the number of vehicles, but also the speed of the traffic should be considered as factors that influence road pollution, as high speeds may accelerate vehicle wear and deposit more heavy metals on road surfaces. In addition to dry deposition, the runoff and water quality was analyzed every five minutes during the first two hours of storm events to capture the properties of the first flush road runoff. The sample mean concentration (SMC) from three roads demonstrated that the first flush runoff had a high pollution content, notably for suspended solid (SS), chemical oxygen demand (COD), oil and grease, Pb, and Zn. Regular sweeping and onsite water treatment facilities are suggested to minimize the pollution from urban roads.

Pollutant concentrations in road runoff: Southeast Queensland case study

Energy Technology Data Exchange (ETDEWEB)

Drapper, D.; Tomlinson, R.; Williams, P.

2000-04-01

This paper discusses the results of research into the pollutants in runoff from road pavement surfaces following natural rainfall events. Road runoff water quality was monitored at 21 sites centering around Brisbane, in southeast Queensland, Australia. The sites were selected according to traffic volumes, surrounding land use, pavement surface type, ease of access, and commercial vehicle percentage. Bridge sites were chosen for convenience of sample collection and minimized infrastructure modification. First flush grab samplers were permanently installed at each site to collect the first 20 L of runoff from one of the bridge drainage scuppers. The runoff samples were tested for a number of heavy metals, hydrocarbons, pesticides, and other physical characteristics. The observed results fall within the ranges of concentrations reported internationally and nationally but do not typically follow the 30,000 average annual daily traffic results reported in the United States. Traffic volumes have not been found to be the best indicator of road runoff pollutant concentrations. Interevent duration has been found to be a statistically significant factor for pollutant concentrations. Sites incorporating exit lanes have recorded higher concentrations of acid-extractable copper and zinc, tending to support the hypothesis that brake pad and tire wear caused by rapid deceleration contributes to the concentrations of these metals in road runoff. Laser particle sizing has shown that a significant proportion of the sediment found in the runoff is <100 {micro}m. However, these particulates do settle in water within 24 h, under laboratory conditions. This may be due to the presence of heavy metals.

Estimation of economic costs of particulate air pollution from road transport in China

Science.gov (United States)

Guo, X. R.; Cheng, S. Y.; Chen, D. S.; Zhou, Y.; Wang, H. Y.

2010-09-01

Valuation of health effects of air pollution is becoming a critical component of the performance of cost-benefit analysis of pollution control measures, which provides a basis for setting priorities for action. Beijing has focused on control of transport emission as vehicular emissions have recently become an important source of air pollution, particularly during Olympic games and Post-games. In this paper, we conducted an estimation of health effects and economic cost caused by road transport-related air pollution using an integrated assessment approach which utilizes air quality model, engineering, epidemiology, and economics. The results show that the total economic cost of health impacts due to air pollution contributed from transport in Beijing during 2004-2008 was 272, 297, 310, 323, 298 million US (mean value), respectively. The economic costs of road transport accounted for 0.52, 0.57, 0.60, 0.62, and 0.58% of annual Beijing GDP from 2004 to 2008. Average cost per vehicle and per ton of PM 10 emission from road transport can also be estimated as 106 US /number and 3584 US $ t -1, respectively. These findings illustrate that the impact of road transport contributed particulate air pollution on human health could be substantial in Beijing, whether in physical and economic terms. Therefore, some control measures to reduce transport emissions could lead to considerable economic benefit.

dispersion characteristics of settleable and dissolvable pollutants in ...

African Journals Online (AJOL)

The implication of this in waste stabilization pond design was also discussed. KEYWORDS: Dispersion, settleable pollutants, waste stabilization ponds. INTRODUCTION. A waste ...... and Soil Pollution 52, 237-245. Agunwamba, J. C., 1991.

Wind tunnel experimental study on effect of inland nuclear power plant cooling tower on air flow and dispersion of pollutant

International Nuclear Information System (INIS)

Qiao Qingdang; Yao Rentai; Guo Zhanjie; Wang Ruiying; Fan Dan; Guo Dongping; Hou Xiaofei; Wen Yunchao

2011-01-01

A wind tunnel experiment for the effect of the cooling tower at Taohuajiang nuclear power plant on air flow and dispersion of pollutant was introduced in paper. Measurements of air mean flow and turbulence structure in different directions of cooling tower and other buildings were made by using an X-array hot wire probe. The effects of the cooling tower and its drift on dispersion of pollutant from the stack were investigated through tracer experiments. The results show that the effect of cooling tower on flow and dispersion obviously depends on the relative position of stack to cooling towers, especially significant for the cooling tower parallel to stack along wind direction. The variation law of normalized maximum velocity deficit and perturbations in longitudinal turbulent intensity in cooling tower wake was highly in accordance with the result of isolated mountain measured by Arya and Gadiyaram. Dispersion of pollutant in near field is significantly enhanced and plume trajectory is changed due to the cooling towers and its drift. Meanwhile, the effect of cooling tower on dispersion of pollutant depends on the height of release. (authors)

The Measurement of Dry Deposition and Surface Runoff to Quantify Urban Road Pollution in Taipei, Taiwan

Science.gov (United States)

Wang, Yunn-Jinn; Chen, Chi-Feng; Lin, Jen-Yang

2013-01-01

Pollutants deposited on road surfaces and distributed in the environment are a source of nonpoint pollution. Field data are traditionally hard to collect from roads because of constant traffic. In this study, in cooperation with the traffic administration, the dry deposition on and road runoff from urban roads was measured in Taipei City and New Taipei City, Taiwan. The results showed that the dry deposition is 2.01–5.14 g/m2·day and 78–87% of these solids are in the 75–300 µm size range. The heavy metals in the dry deposited particles are mainly Fe, Zn, and Na, with average concentrations of 34,978, 1,519 and 1,502 ppm, respectively. Elevated express roads show the highest heavy metal concentrations. Not only the number of vehicles, but also the speed of the traffic should be considered as factors that influence road pollution, as high speeds may accelerate vehicle wear and deposit more heavy metals on road surfaces. In addition to dry deposition, the runoff and water quality was analyzed every five minutes during the first two hours of storm events to capture the properties of the first flush road runoff. The sample mean concentration (SMC) from three roads demonstrated that the first flush runoff had a high pollution content, notably for suspended solid (SS), chemical oxygen demand (COD), oil and grease, Pb, and Zn. Regular sweeping and onsite water treatment facilities are suggested to minimize the pollution from urban roads. PMID:24135820

[Effect of greenbelt on pollutant dispersion in street canyon].

Science.gov (United States)

Xu, Wei-Jia; Xing, Hong; Yu, Zhi

2012-02-01

The effect feature of greenbelt on flow field and pollutant dispersion in urban street canyon was researched. The greenbelt was assumed as uniform porous media and its aerodynamics property defined by the pressure loss coefficient. Subsequently, the pollutant dispersion in the street canyon of which there was greenbelt in the middle was simulated with the steady-state standard kappa-epsilon turbulence model and species transport equation. The simulated results agreed well with the wind-tunnel data. Compared with the treeless case, it finds that the street canyon contain a clockwise vortex, the pollutant concentration of the leeward was several times than the windward and the growth rate of pollutant concentration was 46.0%. The further simulation for the impact of tree crown position on the airflow and pollutant dispersion finds that the height of major vortex center in the street canyon increases with the height of tree crown and gradually closes the top of windward building This causes that the average wind speed in the street canyon decreases. Especially when the top of tree crown over the roof and hinder the air flow above the street canyon, the average pollutant concentration increases with the height of tree crown rapidly.

A numerical study of diurnally varying surface temperature on flow patterns and pollutant dispersion in street canyons

Science.gov (United States)

Tan, Zijing; Dong, Jingliang; Xiao, Yimin; Tu, Jiyuan

2015-03-01

The impacts of the diurnal variation of surface temperature on street canyon flow pattern and pollutant dispersion are investigated based on a two-dimensional street canyon model under different thermal stratifications. Uneven distributed street temperature conditions and a user-defined wall function representing the heat transfer between the air and the street canyon are integrated into the current numerical model. The prediction accuracy of this model is successfully validated against a published wind tunnel experiment. Then, a series of numerical simulations representing four time scenarios (Morning, Afternoon, Noon and Night) are performed at different Bulk Richardson number (Rb). The results demonstrate that uneven distributed street temperature conditions significantly alters street canyon flow structure and pollutant dispersion characteristics compared with conventional uniform street temperature assumption, especially for the morning event. Moreover, air flow patterns and pollutant dispersion are greatly influenced by diurnal variation of surface temperature under unstable stratification conditions. Furthermore, the residual pollutant in near-ground-zone decreases as Rb increases in noon, afternoon and night events under all studied stability conditions.

Numerical study on flow and pollutant dispersion inside street canyons

OpenAIRE

Yunkai, Yang

2013-01-01

This thesis analyzes the characteristics of flow pattern and vehicle-emitted pollutant dispersion in roughness surface layer. In an urban environment, wind flow and transported-pollutant source interfere strongly with buildings and other roughness elements on the surface ground, which results in complex characteristics of flow pattern and pollutant dispersion in 3D circumstances. The present study intends to simplify the research domain and investigate the fundamental modeling problems that e...

Computer Simulation for Dispersion of Air Pollution Released from a Line Source According to Gaussian Model

International Nuclear Information System (INIS)

Emad, A.A.; El Shazly, S.M.; Kassem, Kh.O.

2010-01-01

A line source model, developed in laboratory of environmental physics, faculty of science at Qena, Egypt is proposed to describe the downwind dispersion of pollutants near roadways, at different cities in Egypt. The model is based on the Gaussian plume methodology and is used to predict air pollutants' concentrations near roadways. In this direction, simple software has been presented in this paper, developed by authors, adopted completely Graphical User Interface (GUI) technique for operating in various windows-based microcomputers. The software interface and code have been designed by Microsoft Visual basic 6.0 based on the Gaussian diffusion equation. This software is developed to predict concentrations of gaseous pollutants (eg. CO, SO 2 , NO 2 and particulates) at a user specified receptor grid

Road traffic noise, air pollution and myocardial infarction: a prospective cohort study.

Science.gov (United States)

Bodin, Theo; Björk, Jonas; Mattisson, Kristoffer; Bottai, Matteo; Rittner, Ralf; Gustavsson, Per; Jakobsson, Kristina; Östergren, Per-Olof; Albin, Maria

2016-07-01

Both road traffic noise and air pollution have been linked to cardiovascular disease. However, there are few prospective epidemiological studies available where both road traffic noise and air pollution have been analyzed simultaneously. The aim of this study was to investigate the relation between road traffic noise, air pollution and incident myocardial infarction in both current (1-year average) and medium-term (3-year average) perspective. This study was based on a stratified random sample of persons aged 18-80 years who answered a public health survey in Skåne, Sweden, in 2000 (n = 13,512). The same individuals received a repeated survey in 2005 and 2010. Diagnoses of myocardial infarction (MI) were obtained from medical records for both inpatient and outpatient specialized care. The endpoint was first MI during 2000-2010. Participants with prior myocardial infarction were excluded at baseline. Yearly average levels of noise (L DEN) and air pollution (NO x ) were estimated using geographic information system for residential address every year until censoring. The mean exposure levels for road traffic noise and air pollution in 2005 were L DEN 51 dB(A) and NO x 11 µg/m(3), respectively. After adjustment for individual confounders (age, sex, body mass index, smoking, education, alcohol consumption, civil status, year, country of birth and physical activity), a 10-dB(A) increase in current noise exposure did not increase the incidence rate ratio (IRR) for MI, 0.99 (95 % CI 0.86-1.14). Neither did a 10-μg/m(3) increase in current NO x increase the risk of MI, 1.02 (95 % CI 0.86-1.21). The IRR for MI associated with combined exposure to road traffic noise >55 dB(A) and NO x >20 µg/m(3) was 1.21 (95 % CI 0.90-1.64) compared to noise or air pollution at moderate average exposure levels.

The Brooklyn traffic real-time ambient pollutant penetration and environmental dispersion (B-TRAPPED) field study methodology.

Science.gov (United States)

Richmond-Bryant, Jennifer; Hahn, Intaek; Fortune, Christopher R; Rodes, Charles E; Portzer, Jeffrey W; Lee, Sangdon; Wiener, Russell W; Smith, Luther A; Wheeler, Michael; Seagraves, Jeremy; Stein, Mark; Eisner, Alfred D; Brixey, Laurie A; Drake-Richman, Zora E; Brouwer, Lydia H; Ellenson, William D; Baldauf, Richard

2009-12-01

The Brooklyn Traffic Real-Time Ambient Pollutant Penetration and Environmental Dispersion (B-TRAPPED) field study examined indoor and outdoor exposure to traffic-generated air pollution by studying the individual processes of generation of traffic emissions, transport and dispersion of air contaminants along a roadway, and infiltration of the contaminants into a residence. Real-time instrumentation was used to obtain highly resolved time-series concentration profiles for a number of air pollutants. The B-TRAPPED field study was conducted in the residential Sunset Park neighborhood of Brooklyn, NY, USA, in May 2005. The neighborhood contained the Gowanus Expressway (Interstate 278), a major arterial road (4(th) Avenue), and residential side streets running perpendicular to the Gowanus Expressway and 4(th) Avenue. Synchronized measurements were obtained inside a test house, just outside the test house façade, and along the urban residential street canyon on which the house was located. A trailer containing Federal Reference Method (FRM) and real-time monitors was located next to the Gowanus Expressway to assess the source. Ultrafine particulate matter (PM), PM(2.5), nitrogen oxides (NO(x)), sulfur dioxide (SO(2)), carbon monoxide (CO), carbon dioxide (CO(2)), temperature, relative humidity, and wind speed and direction were monitored. Different sampling schemes were devised to focus on dispersion along the street canyon or infiltration into the test house. Results were obtained for ultrafine PM, PM(2.5), criteria gases, and wind conditions from sampling schemes focused on street canyon dispersion and infiltration. For comparison, the ultrafine PM and PM(2.5) results were compared with an existing data set from the Los Angeles area, and the criteria gas data were compared with measurements from a Vancouver epidemiologic study. Measured ultrafine PM and PM(2.5) concentration levels along the residential urban street canyon and at the test house façade in Sunset Park

Pollutant Removal, Dispersion and Entrainment over Two-Dimensional Idealized Street Canyons: an LES Approach

Science.gov (United States)

Wong, C.; Liu, C.

2010-12-01

Unlike pollutant transport over flat terrain, the mechanism and plume dispersion over urban areas is not well known. This study is therefore conceived to examine how urban morphology modifies the pollutant transport over urban areas. The computational domain and boundary condition used in this study is shown in Figure 1. The LES shows that inside the street canyon, the ground-level pollutants are carried to roof-level by the re-circulating flow, which are then removed from the street canyon to the UBL. Right above the roof level, narrow high-speed air masses in the streamwise flows and intensive downdrafts have been found in the shear layer. Different from the flows over a smooth surface, the maximum turbulence intensities descend that are peaked near the top of the building roughness. The pollutant is rather uniformly distributed inside a street canyon but disperses rapidly over the buildings exhibiting a Gaussian-plume form in the UBL. The mean component of vertical pollutant flux shows that the mean wind contributes to pollutant removal and entrainment simultaneously. Whereas, the fluctuating component demystifies that pollutant removal is mainly governed by atmospheric turbulence. Over the roof level, atmospheric flows slow down rapidly in the wake behind leeward building, suggesting the momentum entrainment into the street canyons. The decelerating streamwise flows in turn lead to upward flows carrying pollutants away from the street canyons, illustrating the basic pollutant removal mechanism in the skimming flow regime. Figure 1: Computational domain and boundary conditions Figure 2: Ensemble average vertical pollutant flux along the roof level. (a). Mean component; (b). turbulent component.

Pollutant dispersion models for issues of air pollution control

International Nuclear Information System (INIS)

1985-01-01

14 papers entered separately into the data base were presented at the meeting for application-oriented dispersion models for issues of air pollution control. These papers focus on fields of application, availability of required input data relevant to emissions and meteorology, performance and accuracy of these methods and their practicability. (orig./PW) [de

mathematical modelling of atmospheric dispersion of pollutants

International Nuclear Information System (INIS)

Mohamed, M.E.

2002-01-01

the main objectives of this thesis are dealing with environmental problems adopting mathematical techniques. in this respect, atmospheric dispersion processes have been investigated by improving the analytical models to realize the realistic physical phenomena. to achieve these aims, the skeleton of this work contained both mathematical and environmental topics,performed in six chapters. in chapter one we presented a comprehensive review study of most important informations related to our work such as thermal stability , plume rise, inversion, advection , dispersion of pollutants, gaussian plume models dealing with both radioactive and industrial contaminants. chapter two deals with estimating the decay distance as well as the decay time of either industrial or radioactive airborne pollutant. further, highly turbulent atmosphere has been investigated as a special case in the three main thermal stability classes namely, neutral, stable, and unstable atmosphere. chapter three is concerned with obtaining maximum ground level concentration of air pollutant. the variable effective height of pollutants has been considered throughout the mathematical treatment. as a special case the constancy of effective height has been derived mathematically and the maximum ground level concentration as well as its location have been established

Using continuous sampling to examine the distribution of traffic related air pollution in proximity to a major road

Science.gov (United States)

McAdam, Kim; Steer, Peter; Perrotta, Kim

2011-04-01

A study to characterize the distribution of vehicle related air pollution in proximity to a major arterial road was undertaken to inform local land use planning and policy regarding separation distances that could help reduce exposure for new sensitive land use development. Measurements of criteria air contaminants were made at ground level, 10 m, 30 m, and 60 m from curb side, and at 9 m height, 10 m from curb side along a traffic corridor carrying over 34,000 vehicles per day. Pollutant decay with distance or height was not statistically significant for O 3, CO, or SO 2. No clear distance decay pattern emerged for PM 2.5. Compared to concentrations at ground level 30 m from curb side, concentrations at 10 m, 60 m, and 10 m at 9 m height were 83%, 45% and 54% higher, respectively. For NO, NO 2, and NO x, however, there was a statistically significant decline in concentrations with distance with the decay most apparent from 30 m to 60 m from the road. Concentrations at 10 m from curb side at 9 m height were equivalent to (all wind conditions) or less than (downwind conditions) those at 30 m and ground level. These findings suggest that for protection of public health in the near road environment, vertical distance is an important determinant of exposure to pollutants that are key indicators of traffic related air pollution. This has implications for sensitive land use development in proximity to high volume traffic corridors.

[Characteristics of fugitive dust emission from paved road near construction activities].

Science.gov (United States)

Tian, Gang; Fan, Shou-Bin; Li, Gang; Qin, Jian-Ping

2007-11-01

Because of the mud/dirt carryout from construction activities, the silt loading of paved road nearby is higher and the fugitive dust emission is stronger. By sampling and laboratory analysis of the road surface dust samples, we obtain the silt loading (mass of material equal to or less than 75 micromaters in physical diameter per unit area of travel surface) of paved roads near construction activities. The result show that silt loading of road near construction activities is higher than "normal road", and silt loading is negatively correlated with length from construction's door. According to AP-42 emission factor model of fugitive dust from roads, the emission factor of influenced road is 2 - 10 times bigger than "normal road", and the amount of fugitive dust emission influenced by one construction activity is "equivalent" to an additional road length of approximately 422 - 3 800 m with the baseline silt loading. Based on the spatial and temporal distribution of construction activities, in 2002 the amount of PM10 emission influenced by construction activities in Beijing city areas account of for 59% of fugitive dust from roads.

PREDICTION OF ATMOSPHERIC AIR POLLUTION BY EMISSIONS OF MOTOR TRANSPORT TAKING INTO ACCOUNT THE CHEMICAL TRANSFORMATION OF HARMFUL SUBSTANCES

Directory of Open Access Journals (Sweden)

M. M. Biliaiev

2017-06-01

Full Text Available Purpose. Development of 3D numerical models, which allow us to calculate air pollution process from road transport emissions based on chemical transformation of pollutants. Creating numerical models, which would give the opportunity to predict the level of air pollution in urban areas. Methodology. To address the evaluation of the air pollution problem of emissions of vehicles the equations of aerodynamics and mass transfer were used. In order to solve differential equations of aerodynamics and mass transfer the finite difference methods are used. For the numerical integration of the equation for the velocity potential the method of conditional approximation was applied. The equation for the velocity potential written in difference form, is being split into two equations, and at each step of splitting the unknown value of the potential speed is determined by the explicit scheme of running account and the difference scheme itself is implicit. For the numerical integration of the equation of dispersion of emissions in the atmosphere is used implicit alternating-triangular difference splitting scheme. Emissions from the road are simulated by a series of point sources of a given intensity. The developed numerical models are the basis of established software package.Findings. There were developed 3D numerical models, which belong to the class «diagnostic models». These models take into account the main physical factors affecting the process of dispersion of pollutants in the atmosphere when emissions from road transport taking into account the chemical transformation of pollutants. On the basis of the constructed numerical models a computational experiment to assess the level of air pollution in the street was carried out. Originality. Numerical models that allow you to calculate the 3D aerodynamic of wind flow in urban areas and the process of mass transfer of emissions from the road were developed. The models make it possible to account the

Combined effects of road traffic noise and ambient air pollution in relation to risk for stroke?

Science.gov (United States)

Sørensen, Mette; Lühdorf, Pernille; Ketzel, Matthias; Andersen, Zorana J; Tjønneland, Anne; Overvad, Kim; Raaschou-Nielsen, Ole

2014-08-01

Exposure to road traffic noise and air pollution have both been associated with risk for stroke. The few studies including both exposures show inconsistent results. We aimed to investigate potential mutual confounding and combined effects between road traffic noise and air pollution in association with risk for stroke. In a population-based cohort of 57,053 people aged 50-64 years at enrollment, we identified 1999 incident stroke cases in national registries, followed by validation through medical records. Mean follow-up time was 11.2 years. Present and historical residential addresses from 1987 to 2009 were identified in national registers and road traffic noise and air pollution were modeled for all addresses. Analyses were done using Cox regression. A higher mean annual exposure at time of diagnosis of 10 µg/m(3) nitrogen dioxide (NO2) and 10 dB road traffic noise at the residential address was associated with ischemic stroke with incidence rate ratios (IRR) of 1.11 (95% CI: 1.03, 1.20) and 1.16 (95% CI: 1.07, 1.24), respectively, in single exposure models. In two-exposure models road traffic noise (IRR: 1.15) and not NO2 (IRR: 1.02) was associated with ischemic stroke. The strongest association was found for combination of high noise and high NO2 (IRR=1.28; 95% CI=1.09-1.52). Fatal stroke was positively associated with air pollution and not with traffic noise. In conclusion, in mutually adjusted models road traffic noise and not air pollution was associated ischemic stroke, while only air pollution affected risk for fatal strokes. There were indications of combined effects. Copyright © 2014 Elsevier Inc. All rights reserved.

Road user charges for heavy goods vehicles (HGV). Tables with external costs of air pollution

Energy Technology Data Exchange (ETDEWEB)

Skou Andersen, M.

2013-02-15

In this report, the European Environment Agency (EEA) presents updated estimates of the external costs of air pollution for different categories of heavy goods vehicles (HGVs). The amended Eurovignette Directive (2011/76/EU) relating to the charging of HGVs for use of major European motorways prescribes that from 2013, Member States may include air pollution costs in any charging structure for roads under the Trans-European Network (TEN-T) and for comparable domestic motorways. The tables published here provide the basis for the inclusion of a vehicle-specific air pollution component in road user charges. Air pollution costs have been calculated on the basis of the formula prescribed in the directive, taking into account the fact that road transport emissions are mixed in a low volume of air. Following Article 9 in the Eurovignette Directive, additional revenues from external-cost charges must be used by Member States to benefit the transport sector and promote sustainable mobility. Making use of scientific developments subsequent to the 2007 Handbook of external costs (Maibach et al., 2008), the EEA is able to provide an updated estimate of the external costs of air pollution from road transport. The tables in this report indicate for each country and for the relevant vehicle categories, estimates of the external costs of air pollution in 2010 prices. The high level of detail gives member countries an informed basis to group the vehicle categories for administrative purposes. The tables also include estimates for three non-EU member countries of the EEA, of which one (Switzerland) pioneered the first HGV road user charge in Europe. (LN)

Air pollutant concentrations near three Texas roadways, Part I: Ultrafine particles

Science.gov (United States)

Zhu, Yifang; Pudota, Jayanth; Collins, Donald; Allen, David; Clements, Andrea; DenBleyker, Allison; Fraser, Matt; Jia, Yuling; McDonald-Buller, Elena; Michel, Edward

Vehicular emitted air pollutant concentrations were studied near three types of roadways in Austin, Texas: (1) State Highway 71 (SH-71), a heavily traveled arterial highway dominated by passenger vehicles; (2) Interstate 35 (I-35), a limited access highway north of Austin in Georgetown; and (3) Farm to Market Road 973 (FM-973), a heavily traveled surface roadway dominated by truck traffic. Air pollutants examined include carbon monoxide (CO), oxides of nitrogen (NO x), and carbonyl species in the gas-phase. In the particle phase, ultrafine particle (UFP) concentrations (diameter road were found to be the most important factors determining UFP concentrations near the roadways. Since wind directions were not consistent during the sampling periods, distances along wind trajectories from the roadway to the sampling points were used to study the decay characteristics of UFPs. Under perpendicular wind conditions, for all studied roadway types, particle number concentrations increased dramatically moving from the upwind side to the downwind side. The elevated particle number concentrations decay exponentially with increasing distances from the roadway with sharp concentration gradients observed within 100-150 m, similar to previously reported studies. A single exponential decay curve was found to fit the data collected from all three roadways very well under perpendicular wind conditions. No consistent pattern was observed for UFPs under parallel wind conditions. However, regardless of wind conditions, particle concentrations returned to background levels within a few hundred meters of the roadway. Within measured UFP size ranges, smaller particles (6-25 nm) decayed faster than larger ones (100-300 nm). Similar decay rates were observed among UFP number, surface, and volume.

Urban air pollution in school-related microenvironments in Bogota, Colombia

Directory of Open Access Journals (Sweden)

Juan Felipe Franco

2013-05-01

Full Text Available Particle-related pollution (PM10, PM2.5 and soot was measured in both indoor and outdoor microenvironments at four public elementary schools in Bogota, Colombia. Three of these schools were located alongside major urban roads in which different types of public transit systems are used (bus rapid transit system and conventional transit buses. The fourth school was located on a non-congested road (background school. Pollutant levels at schools situated on major-roads were higher than those found at the low-congestion-road school. Outdoor black carbon daily mean concentrations at the schools located near major roads were up to six times higher than those recorded at the background school. Mean particulate matter concentrations at schools near major roads were above international standards, suggesting that school-age children in Bogota are exposed to pollution levels that are considered to be harmful by environmental and public health authorities. Elevated indoor and outdoor pollutant concentrations documented in this study suggested that traffic has a direct impact on air quality regarding the schools’ characterised microenvironments.

Pollution level and health risk assessment of road dust from Islamabad expressway, Pakistan

International Nuclear Information System (INIS)

Faiz, Y.; Siddique, N.

2012-01-01

Thirteen road dust and four soil samples were analyzed using instrumental neutron activation analysis (INAA) to determine the elemental composition of road dust collected from Islamabad Expressway. The amounts of most of the elements determined were generally in the lower range of the global data with the exception of Ce, Nd, Sn and Zr which were measured at higher concentrations in Islamabad. Pollution parameters and indicators such as Enrichment Factors (EFs), Pollution Load Index (PLI), Geo accumulation Index (Igeo), Pollution Index (PI) and Integrated Pollution Index (IPI) showed that the area around Islamabad Expressway is low to moderately polluted especially by elements such as Mg and Sb. The IPI of the elements was found to vary in the order; Mg>Sb>Cu>Sr Pb>Ga>Na >Sn Zn>Yb>Se>Hf. Elemental health risk was assessed through dose calculations for carcinogenic and non carcinogenic metals; and by the determination of LADD (lifetime average daily dose). The carcinogenic metals studied showed the following variation in their LADD values; Cr>Ni>Co>Cd>As. Dose calculations for non-cancerous and cancerous elements showed the data obtained to lie within the safe threshold of 10 3 10 6 mg kg/sup -1/ day/sup -1/ for most elements. The soil based elements Al, Fe, K, Mg, Na and Ti were the exception and originated from the exposed soil around the highway. Moreover highest Hazard Index (HI) was found to be associated with the presence of Al, Cr, Pb and V in road dust showing soil, transport and industry to be the major sources of road dust. (orig./A.B.)

Plant pollution from lead produced by automobile exhaust system near certain highways of Iran

International Nuclear Information System (INIS)

Rahmani, H.R.; Kalbasi, M.; Hajrasuliha, Sh.

2001-01-01

Plants polluted with Pb produced by automobiles along the roads and highways have extensively been reported all over the world. It is the most important source of pollution in the environment. This research was carried out to determine the polluting degree of plants along the highways such as: Rasht-Anzaly, Kelachay-Ramsar, Tehran-Karaj, and Isfahan-Tehran. At each arbitrary point, a transect 100 meters long perpendicular to the highway was selected for sampling. Along each transect, plants were sampled at 15 cm above the ground, in different distances from the highway. Samples were transported to the laboratory and analyzed by a standard method. The average concentration of total Pb determined in Anzali, Ramsar, Karaj and Delijan (east and west of the road) areas respectively were 114.5, 58.3, 260.2, 75.1 and microgram per gram dry plant weight. Total Pb content in plants along the roads were high and exponentially decreasing with distance from the roadside. Pb concentration in plants were higher than threshold of Standard, so the risk of entrain g of this poisonous element in nutrition system along the roads is very considerable. The plants were polluted from medium degree up to a very high degree. The rate of pollution in plant samples is very high in Karaj area, high in Anzali area, and medium in Ramsar and Delijan areas. Plant pollution was directly related to the traffic volume in road

[Environmental pollution by products of wear and tear automobile-road complex].

Science.gov (United States)

Levanchuk, A V

2014-01-01

North-West State Medical University named after I.I. Mechnikov, Saint Petersburg, Russian Federation, 191015. There is supposed the method for the assessment of amounts of pollutants released into the environment during the operational wear of tyre treads, brake system of cars and the road pavement. There are presented results of chemical analysis of residues of combustion. The necessity of control of products of work wear of automobile-road complex has been substantiated.

Assessing vanadium and arsenic exposure of people living near a petrochemical complex with two-stage dispersion models

International Nuclear Information System (INIS)

Chio, Chia-Pin; Yuan, Tzu-Hsuen; Shie, Ruei-Hao; Chan, Chang-Chuan

2014-01-01

Highlights: • Two-stage dispersion models can estimate exposures to hazardous air pollutants. • Spatial distribution of V levels is derived for sources without known emission rates. • A distance-to-source gradient is found for V levels from a petrochemical complex. • Two-stage dispersion is useful for modeling air pollution in resource-limited areas. - Abstract: The goal of this study is to demonstrate that it is possible to construct a two-stage dispersion model empirically for the purpose of estimating air pollution levels in the vicinity of petrochemical plants. We studied oil refineries and coal-fired power plants in the No. 6 Naphtha Cracking Complex, an area of 2,603-ha situated on the central west coast of Taiwan. The pollutants targeted were vanadium (V) from oil refineries and arsenic (As) from coal-fired power plants. We applied a backward fitting method to determine emission rates of V and As, with 192 PM 10 filters originally collected between 2009 and 2012. Our first-stage model estimated emission rates of V and As (median and 95% confidence intervals at 0.0202 (0.0040–0.1063) and 0.1368 (0.0398–0.4782) g/s, respectively. In our second stage model, the predicted zone-average concentrations showed a strong correlation with V, but a poor correlation with As. Our findings show that two-stage dispersion models are relatively precise for estimating V levels at residents’ addresses near the petrochemical complex, but they did not work as well for As levels. In conclusion, our model-based approach can be widely used for modeling exposure to air pollution from industrial areas in countries with limited resources

Road Traffic Noise Pollution Analysis for Cernavoda City

Science.gov (United States)

Manea, L.; Manea, A.; Florea, D.; Tarulescu, S.

2017-10-01

In the present paper was studied the noise pollution in Cernavodă city. The noise measurements were made for nine intersections from different city areas. Noise measurements were taken for three chosen routes with high population density, heavy traffic, commercial and residential buildings. Average, maximum and minimum values were collected and compared with standards. The impact of road traffic noise on the community depends on various factors such as road location and design, land use planning measures, building design, traffic composition, driver behaviour and the relief. In the study area 9 locations are identified to measure noise level. By using sound level meter noise levels are measured at different peak sessions i.e. morning, afternoon and evening. The presented values were collected for evening rush hour.

A Numerical Study on the Effects of Street‒canyon Aspect‒ratio on Reactive Pollutant Dispersion

Science.gov (United States)

Park, S. J.; Kim, J.

2014-12-01

In this study, the effects of street‒canyon aspect‒ratio on reactive pollutant dispersion were investigated using the coupled CFD‒chemistry model. For this, flow characteristics were analyzed first in street canyons with different aspect ratios and flow regimes were classified according to the building height. For each flow regime, dispersion characteristics were investigated in views of reactive pollutant concentration and VOCs‒NOX ratio. Finally, the relations between pollutant concentration and aspect ratio in urban street canyons were investigated. In the case of H/S = 1.0 (H is building height and S is street width), one clockwise‒rotating vortex appeared vertically and the reverse and outward flows were dominant near the street bottom. In the case of H/S = 2.0, two counter‒rotating vortices appeared vertically in the street canyon. The primary (secondary) vortex rotating clockwise (counterclockwise) was formed in upper (lower) layer. The flow patterns affected the reactive pollutant concentration in street canyons. As building height increased, mean concentration of NO decreased when one vortex was generated in street canyons and increased when two vortexes appeared in street canyons. O3 concentration showed almost contrasted tendency with those of NO because O3 was depleted by the NO titration.

Disperse reinforced concrete used in obtaining prefabricated elements for roads

Directory of Open Access Journals (Sweden)

Bogdan MEZEI

2014-07-01

Full Text Available Concrete is the most used material in construction. By improving the performance of materials and of technologies, concretes with outstanding performances were also developed, in the past two decades. Concrete with dispersed reinforcement represents a new generation of reinforced concrete that combines a good behavior of concrete compressive strength with an increased tensile strength of steel fibers. Using this material, monolithic and prefabricated concrete elements with high mechanical strengths and high durability can be obtained. Technological processes for preparation of concrete with dispersed reinforcement are similar to the conventional methods and do not involve using additional equipment for dosing the dispersed reinforcement. The study aimed the development of road plates made with optimized disperse- reinforced concrete. The first tests were done on plates from the gutter roadway, having a classic reinforcement, using different percentages of fibre reinforcement in the concrete composition, leading to the development of a new optimized economical solution. The results prove the enhanced characteristics of the disperse-reinforced concrete versus conventional concrete, and hence of the developed concrete plates.

On the impact of snow cover on daytime pollution dispersion

Science.gov (United States)

Segal, M.; Garratt, J. R.; Pielke, R. A.; Hildebrand, P.; Rogers, F. A.; Cramer, J.; Schanot, A.

A preliminary evaluation of the impact of snow cover on daytime pollutant dispersion conditions is made by using conceptual, scaling, and observational analyses. For uniform snow cover and synoptically unperturbed sunny conditions, observations indicate a considerate suppression of the surface sensible heat flux, the turbulence, and the development of the daytime atmospheric boundary layer (ABL) when compared to snow-free conditions. However, under conditions of non-uniform snow cover, as in urban areas, or associated with vegetated areas or bare ground patches, a milder effect on pollutant dispersion conditions would be expected. Observed concentrations of atmospheric particles within the ABL, and surface pollutant concentrations in urban areas, reflect the impact of snow cover on the modification of ABL characteristics.

Use of the landfill water pollution index (LWPI) for groundwater quality assessment near the landfill sites.

Science.gov (United States)

Talalaj, Izabela A; Biedka, Pawel

2016-12-01

The purpose of the paper is to assess the groundwater quality near the landfill sites using landfill water pollution index (LWPI). In order to investigate the scale of groundwater contamination, three landfills (E, H and S) in different stages of their operation were taken into analysis. Samples of groundwater in the vicinity of studied landfills were collected four times each year in the period from 2004 to 2014. A total of over 300 groundwater samples were analysed for pH, EC, PAH, TOC, Cr, Hg, Zn, Pb, Cd, Cu, as required by the UE legal acts for landfill monitoring system. The calculated values of the LWPI allowed the quantification of the overall water quality near the landfill sites. The obtained results indicated that the most negative impact on groundwater quality is observed near the old Landfill H. Improper location of piezometer at the Landfill S favoured infiltration of run-off from road pavement into the soil-water environment. Deep deposition of the groundwater level at Landfill S area reduced the landfill impact on the water quality. Conducted analyses revealed that the LWPI can be used for evaluation of water pollution near a landfill, for assessment of the variability of water pollution with time and for comparison of water quality from different piezometers, landfills or time periods. The applied WQI (Water Quality Index) can also be an important information tool for landfill policy makers and the public about the groundwater pollution threat from landfill.

Statistical classification of road pavements using near field vehicle rolling noise measurements.

Science.gov (United States)

Paulo, Joel Preto; Coelho, J L Bento; Figueiredo, Mário A T

2010-10-01

Low noise surfaces have been increasingly considered as a viable and cost-effective alternative to acoustical barriers. However, road planners and administrators frequently lack information on the correlation between the type of road surface and the resulting noise emission profile. To address this problem, a method to identify and classify different types of road pavements was developed, whereby near field road noise is analyzed using statistical learning methods. The vehicle rolling sound signal near the tires and close to the road surface was acquired by two microphones in a special arrangement which implements the Close-Proximity method. A set of features, characterizing the properties of the road pavement, was extracted from the corresponding sound profiles. A feature selection method was used to automatically select those that are most relevant in predicting the type of pavement, while reducing the computational cost. A set of different types of road pavement segments were tested and the performance of the classifier was evaluated. Results of pavement classification performed during a road journey are presented on a map, together with geographical data. This procedure leads to a considerable improvement in the quality of road pavement noise data, thereby increasing the accuracy of road traffic noise prediction models.

Investigation on the pollution of road rainwater runoff in Shijiazhuang City

Directory of Open Access Journals (Sweden)

Tongjun GUAN

2017-12-01

Full Text Available To protect groundwater and urban ecological environment, much more sponge cities have been built in China. The sponge road is an important part of a sponge city. In recent years, Shijiazhuang Municipal Design Institute proposes a new sponge road structure, namely planting soil and crushed stone green belt, and it has been extensively used in Shijiazhuang City. In the design of the road structure, it is a key issue whether the infiltration rainwater quality pollutes the groundwater. Therefore, it is necessary to investigate the pollution of road rainwater runoff in Shijiazhuang City for the design of sponge road and the construction of sponge city. To obtain the characteristics of rainwater runoff pollution in Shijiazhuang City, four investigation points are chosen at the intersection of the Nanerhuan Road and Yuxiang Street, the east gate of Hebei University of Science and Technology, the site under the Xierhuan Road and Zhongshan Road overpass, and the catch-basin along the roadside in Shijiazhuang City. The investigating points are located in the main road of Shijiazhuang urban area, which covers Shijiazhuang City, and can represent the pollution characteristics of road runoff in Shijiazhuang City. Six rainfalls are collected from March to June in 2017. The rainfall on 3, May is viewed as typical middle and light one which is studied in this paper. The concentration of COD, TP, TN, NH3-N and SS in road runoff is tested by potassium dichromate method, ammonium molybdate spectrophotometry, potassium persulfate digestion-UV spectrophotometry and Nessler’s reagent spectrophotometry and filter paper filtration, respectively. The concentrations of Zn ions and Pb ions are tested by inductively coupled plasma method. According to the test results, the concentration evolutions of COD, TP, TN, NH3-N, SS, Zn and Pb ion in runoff during rainfall are studied. The results show that the contaminant concentration approximately decreases during the rainfall

Implications of tree planting on pollutant dispersion in street canyons

NARCIS (Netherlands)

Gromke, C.B.; Ruck, B.

2009-01-01

Traffic pollutant dispersion processes inside urban street canyons with avenue-like tree planting have been studied in wind tunnel experiments. Tree planting of different crown porosities and their effects on the pollutant concentrations at the canyon walls have been investigated for wind

Experimental and numerical simulations of the hydrodynamic dispersion of a pollutant effluent in a estuarine coastal zone

International Nuclear Information System (INIS)

Gidas, N.K.; Koutitonsky, V.G.

1996-01-01

An experimental and numerical study was performed to measure and simulate the hydrodynamic dispersion of a pollutant effluent discharged by an outfall diffuser into an estuarine coastal zone near Rimouski, Canada. Field measurements of currents, tides, salinity, and winds were obtained in the vicinity of the injection site, and two tracer dispersion experiments were carried on in these coastal waters. The measurements were taken before and after the construction of the marine outfall diffuser. The similitude between the plume of a tracer (physical model) released into the coastal waters before construction and that of the real effluent (prototype) discharged at the same site was studied. A new coefficient of similitude was established, which allows to transpose the concentrations of the physical model tracer to the waste water concentrations of the prototype. The numerical simulation (2D) is performed with a hydrodynamic model and an advection-dispersion model of the MIKE21 system from the Danish Hydraulic Institute, using the so-called telescopic approach. The objective of these simulations was to predict, among other things, the pollutant effluent concentrations for critical hydrodynamic conditions relative to the aquatic ecosystem to be protected. The methodology elaborated was used for the management of the coastal environments subjected to pollution. (author). 28 refs., 2 tabs., 12 figs

Pollutant Plume Dispersion in the Atmospheric Boundary Layer over Idealized Urban Roughness

Science.gov (United States)

Wong, Colman C. C.; Liu, Chun-Ho

2013-05-01

The Gaussian model of plume dispersion is commonly used for pollutant concentration estimates. However, its major parameters, dispersion coefficients, barely account for terrain configuration and surface roughness. Large-scale roughness elements (e.g. buildings in urban areas) can substantially modify the ground features together with the pollutant transport in the atmospheric boundary layer over urban roughness (also known as the urban boundary layer, UBL). This study is thus conceived to investigate how urban roughness affects the flow structure and vertical dispersion coefficient in the UBL. Large-eddy simulation (LES) is carried out to examine the plume dispersion from a ground-level pollutant (area) source over idealized street canyons for cross flows in neutral stratification. A range of building-height-to-street-width (aspect) ratios, covering the regimes of skimming flow, wake interference, and isolated roughness, is employed to control the surface roughness. Apart from the widely used aerodynamic resistance or roughness function, the friction factor is another suitable parameter that measures the drag imposed by urban roughness quantitatively. Previous results from laboratory experiments and mathematical modelling also support the aforementioned approach for both two- and three-dimensional roughness elements. Comparing the UBL plume behaviour, the LES results show that the pollutant dispersion strongly depends on the friction factor. Empirical studies reveal that the vertical dispersion coefficient increases with increasing friction factor in the skimming flow regime (lower resistance) but is more uniform in the regimes of wake interference and isolated roughness (higher resistance). Hence, it is proposed that the friction factor and flow regimes could be adopted concurrently for pollutant concentration estimate in the UBL over urban street canyons of different roughness.

An index for estimating the potential metal pollution contribution to atmospheric particulate matter from road dust in Beijing.

Science.gov (United States)

Zhao, Hongtao; Shao, Yaping; Yin, Chengqing; Jiang, Yan; Li, Xuyong

2016-04-15

The resuspension of road dust from street surfaces could be a big contributor to atmospheric particulate pollution in the rapid urbanization context in the world. However, to date what its potential contribution to the spatial pattern is little known. Here we developed an innovative index model called the road dust index (RIatmospheric suspended particles. The factors were ranked and weighted based on road dust characteristics (the amounts, grain sizes, and mobilities of the road dust, and the concentrations and toxicities of metals in the road dust). We then applied the RIatmospheric suspended particles. The results demonstrated that the road dust in urban areas has higher potential risk of metal to atmospheric particles than that in rural areas. The RIatmospheric suspended particles and for controlling atmospheric particulate pollution caused by road dust emissions. Copyright © 2016 Elsevier B.V. All rights reserved.

Residential Air Pollution, Road Traffic, Greenness and Maternal Hypertension: Results from GINIplus and LISAplus.

Science.gov (United States)

Jendrossek, Mario; Standl, Marie; Koletzko, Sibylle; Lehmann, Irina; Bauer, Carl-Peter; Schikowski, Tamara; von Berg, Andrea; Berdel, Dietrich; Heinrich, Joachim; Markevych, Iana

2017-07-01

The public health burden of hypertension is high, but its relationship with long-term residential air pollution, road traffic, and greenness remains unclear. To investigate associations between residential air pollution, traffic, greenness, and hypertension among mothers. Information on doctor-diagnosed maternal hypertension was collected at the 15-year follow-up of two large population-based multicenter German birth cohorts-GINIplus and LISAplus (n=3063). Residential air pollution was modelled by land use regression models within the ESCAPE and universal kriging within the APMoSPHERE projects. Road traffic was defined as traffic load on major roads within a 100-m buffer around residences. Vegetation level ( ie , greenness) was defined as the mean Normalized Difference Vegetation Index in a 500-m buffer around residences and was assessed from Landsat 5 TM satellite images. All the exposure variables were averaged over three residential addresses during the last 10 years and categorized into tertiles or dichotomized. The individual associations between each of the exposure variables and hypertension were assessed using logistic regression analysis. No significant and consistent associations across different levels of adjustment were observed between the exposures of interest and hypertension. The only significant estimate was found with coarse particulate matter concentrations (OR 1.66, 95% CI 1.01 to 2.74; 3 rd vs 1 st tertile) among mothers residing in the Wesel area. No significant associations were observed with traffic load or greenness. This study does not provide evidence on detrimental effects of air pollution and road traffic or beneficial effects of greenness on hypertension among German adults.

Influence of low impact development construction on pollutant process of road-deposited sediments and associated heavy metals.

Science.gov (United States)

Ma, Yukun; Gong, Manli; Zhao, Hongtao; Li, Xuyong

2018-02-01

Intense Low-Impact Development (LID) construction in China could lead to increasingly severe stormwater and receiving water pollution due to the lack of appropriate regulation for mitigating pollution from LID construction. Samples of road-deposited sediments (RDS) were collected from 50 study sites at seven LID construction stages and four road hierarchies to analyze the pollution process and determine the size of the region influenced by LID construction. Six heavy metals were analyzed, and the RDS index model was adopted to estimate the potential heavy metal load washed off by stormwater runoff. Analysis of variance revealed that the excavation and gravel filling of rain gardens and excavation of porous pavements were critical LID construction stages that contributed the largest masses of RDS per unit area to road surfaces. Although the concentration of heavy metals at LID construction sites was lower than at sites without LID construction, the load of heavy metals washed off from LID construction was much higher. In addition, the sizes of regions influenced by accumulated RDS from LID construction descended in the following order: arterial road (600-775m)>collector road (150-200m)>access road (100-150m)>laneway (20-30m). According to the characteristics of LID construction at the study sites, the potential total solid loads in stormwater throughout China were estimated to reach 36,694t by 2020 and 146,777t by 2030. According to the results of analysis, several recommendations are provided for designing LID construction regulations to mitigate stormwater pollution. Copyright © 2017 Elsevier B.V. All rights reserved.

Modelling Pollutant Dispersion in a Street Network

Science.gov (United States)

Salem, N. Ben; Garbero, V.; Salizzoni, P.; Lamaison, G.; Soulhac, L.

2015-04-01

This study constitutes a further step in the analysis of the performances of a street network model to simulate atmospheric pollutant dispersion in urban areas. The model, named SIRANE, is based on the decomposition of the urban atmosphere into two sub-domains: the urban boundary layer, whose dynamics is assumed to be well established, and the urban canopy, represented as a series of interconnected boxes. Parametric laws govern the mass exchanges between the boxes under the assumption that the pollutant dispersion within the canopy can be fully simulated by modelling three main bulk transfer phenomena: channelling along street axes, transfers at street intersections, and vertical exchange between street canyons and the overlying atmosphere. Here, we aim to evaluate the reliability of the parametrizations adopted to simulate these phenomena, by focusing on their possible dependence on the external wind direction. To this end, we test the model against concentration measurements within an idealized urban district whose geometrical layout closely matches the street network represented in SIRANE. The analysis is performed for an urban array with a fixed geometry and a varying wind incidence angle. The results show that the model provides generally good results with the reference parametrizations adopted in SIRANE and that its performances are quite robust for a wide range of the model parameters. This proves the reliability of the street network approach in simulating pollutant dispersion in densely built city districts. The results also show that the model performances may be improved by considering a dependence of the wind fluctuations at street intersections and of the vertical exchange velocity on the direction of the incident wind. This opens the way for further investigations to clarify the dependence of these parameters on wind direction and street aspect ratios.

Residential Air Pollution, Road Traffic, Greenness and Maternal Hypertension: Results from GINIplus and LISAplus

Directory of Open Access Journals (Sweden)

Mario Jendrossek

2017-07-01

Full Text Available Background: The public health burden of hypertension is high, but its relationship with long-term residential air pollution, road traffic, and greenness remains unclear. Objective: To investigate associations between residential air pollution, traffic, greenness, and hypertension among mothers. Methods: Information on doctor-diagnosed maternal hypertension was collected at the 15-year follow-up of two large population-based multicenter German birth cohorts—GINIplus and LISAplus (n=3063. Residential air pollution was modelled by land use regression models within the ESCAPE and universal kriging within the APMoSPHERE projects. Road traffic was defined as traffic load on major roads within a 100-m buffer around residences. Vegetation level (ie, greenness was defined as the mean Normalized Difference Vegetation Index in a 500-m buffer around residences and was assessed from Landsat 5 TM satellite images. All the exposure variables were averaged over three residential addresses during the last 10 years and categorized into tertiles or dichotomized. The individual associations between each of the exposure variables and hypertension were assessed using logistic regression analysis. Results: No significant and consistent associations across different levels of adjustment were observed between the exposures of interest and hypertension. The only significant estimate was found with coarse particulate matter concentrations (OR 1.66, 95% CI 1.01 to 2.74; 3rd vs 1st tertile among mothers residing in the Wesel area. No significant associations were observed with traffic load or greenness. Conclusion: This study does not provide evidence on detrimental effects of air pollution and road traffic or beneficial effects of greenness on hypertension among German adults.

The effect of a tall tower on flow and dispersion through a model urban neighborhood: part 2. Pollutant dispersion.

Science.gov (United States)

Brixey, Laurie A; Heist, David K; Richmond-Bryant, Jennifer; Bowker, George E; Perry, Steven G; Wiener, Russell W

2009-12-01

This article is the second in a two-paper series presenting results from wind tunnel and computational fluid dynamics (CFD) simulations of flow and dispersion in an idealized model urban neighborhood. Pollutant dispersion results are presented and discussed for a model neighborhood that was characterized by regular city blocks of three-story row houses with a single 12-story tower located at the downwind edge of one of these blocks. The tower had three significant effects on pollutant dispersion in the surrounding street canyons: drawing the plume laterally towards the tower, greatly enhancing the vertical dispersion of the plume in the wake of the tower, and significantly decreasing the residence time of pollutants in the wake of the tower. In the wind tunnel, tracer gas released in the avenue lee of the tower, but several blocks away laterally, was pulled towards the tower and lifted in the wake of the tower. The same lateral movement of the pollutant was seen in the next avenue, which was approximately 2.5 tower heights downwind of the tower. The tower also served to ventilate the street canyon directly in its wake more rapidly than the surrounding areas. This was evidenced by CFD simulations of concentration decay where the residence time of pollutants lee of the 12-story tower was found to be less than half the residence time behind a neighboring three-story building. This same phenomenon of rapid vertical dispersion lee of a tower among an array of smaller buildings was also demonstrated in a separate set of wind tunnel experiments using an array of cubical blocks. A similar decrease in the residence time was observed when the height of one block was increased.

A numerical study of air pollutant dispersion with bimolecular chemical reactions in an urban street canyon using large-eddy simulation

Science.gov (United States)

Kikumoto, Hideki; Ooka, Ryozo

2012-07-01

A large-eddy simulation is performed on a turbulent dispersion of chemically reactive air pollutants in a two-dimensional urban street canyon with an aspect ratio of 1.0. Nitrogen monoxide emitted from a line-source set on the bottom of the street canyon disperses and reacts with Ozone included in a free stream. The reactions have significant influences on the concentrations of pollutants in the canyon space, and they increase the concentrations of the reaction products relative to of the concentrations of the reactants. The transport of air pollutants through a free shear layer above the canyon is closely related to the structure of the turbulence. Gases in the canyon are mainly exhausted when low-speed regions appear above the canyon. In contrast, pollutants in the free stream flow into the canyon with high-speed fluid bodies. Consequently, the correlation between the time fluctuations of the reactants' concentrations strongly affects the reaction rates in the region near the free shear layer. In this calculation, the correlation term reaches to a value of 20% of the mean reaction rate at a maximum there.

Spatial and temporal differences in traffic-related air pollution in three urban neighborhoods near an interstate highway

Science.gov (United States)

Patton, Allison P.; Perkins, Jessica; Zamore, Wig; Levy, Jonathan I.; Brugge, Doug; Durant, John L.

2014-01-01

Relatively few studies have characterized differences in intra- and inter-neighborhood traffic-related air pollutant (TRAP) concentrations and distance-decay gradients in along an urban highway for the purposes of exposure assessment. The goal of this work was to determine the extent to which intra- and inter-neighborhood differences in TRAP concentrations can be explained by traffic and meteorology in three pairs of neighborhoods along Interstate 93 (I-93) in the metropolitan Boston area (USA). We measured distance-decay gradients of seven TRAPs (PNC, pPAH, NO, NOX, BC, CO, PM2.5) in near-highway (1 km) in Somerville, Dorchester/South Boston, Chinatown and Malden to determine whether (1) spatial patterns in concentrations and inter-pollutant correlations differ between neighborhoods, and (2) variation within and between neighborhoods can be explained by traffic and meteorology. The neighborhoods ranged in area from 0.5 to 2.3 km2. Mobile monitoring was performed over the course of one year in each pair of neighborhoods (one pair of neighborhoods per year in three successive years; 35-47 days of monitoring in each neighborhood). Pollutant levels generally increased with highway proximity, consistent with I-93 being a major source of TRAP; however, the slope and extent of the distance-decay gradients varied by neighborhood as well as by pollutant, season and time of day. Correlations among pollutants differed between neighborhoods (e.g., ρ = 0.35-0.80 between PNC and NOX and ρ = 0.11-0.60 between PNC and BC) and were generally lower in Dorchester/South Boston than in the other neighborhoods. We found that the generalizability of near-road gradients and near-highway/urban background contrasts was limited for near-highway neighborhoods in a metropolitan area with substantial local street traffic. Our findings illustrate the importance of measuring gradients of multiple pollutants under different ambient conditions in individual near-highway neighborhoods for health

Numerical Study of Traffic Pollutant Dispersion within Different Street Canyon Configurations

Directory of Open Access Journals (Sweden)

Yucong Miao

2014-01-01

Full Text Available The objective of this study is to numerically study flow and traffic exhaust dispersion in urban street canyons with different configurations to find out the urban-planning strategies to ease the air pollution. The Computational Fluid Dynamics (CFD model used in this study—Open Source Field Operation and Manipulation (OpenFOAM software package—was firstly validated against the wind-tunnel experiment data by using three different k-ε turbulence models. And then the patterns of flow and dispersion within three different kinds of street canyon configuration under the perpendicular approaching flow were numerically studied. The result showed that the width and height of building can dramatically affect the pollution level inside the street canyon. As the width or height of building increases, the pollution at the pedestrian level increases. And the asymmetric configuration (step-up or step-down street canyon could provide better ventilation. It is recommended to design a street canyon with nonuniform configurations. And the OpenFOAM software package can be used as a reliable tool to study flows and dispersions around buildings.

Methods for estimating wake flow and effluent dispersion near simple block-like buildings

International Nuclear Information System (INIS)

Hosker, R.P. Jr.

1981-05-01

This report is intended as an interim guide for those who routinely face air quality problems associated with near-building exhaust stack placement and height, and the resulting concentration patterns. Available data and methods for estimating wake flow and effluent dispersion near isolated block-like structures are consolidated. The near-building and wake flows are described, and quantitative estimates for frontal eddy size, height and extent of roof and wake cavities, and far wake behavior are provided. Concentration calculation methods for upwind, near-building, and downwind pollutant sources are given. For an upwind source, it is possible to estimate the required stack height, and to place upper limits on the likely near-building concentration. The influences of near-building source location and characteristics relative to the building geometry and orientation are considered. Methods to estimate effective stack height, upper limits for concentration due to flush roof vents, and the effect of changes in rooftop stack height are summarized. Current wake and wake cavity models are presented. Numerous graphs of important expressions have been prepared to facilitate computations and quick estimates of flow patterns and concentration levels for specific simple buildings. Detailed recommendations for additional work are given

Characterization of road runoff with regard to seasonal variations, particle size distribution and the correlation of fine particles and pollutants.

Science.gov (United States)

Hilliges, R; Endres, M; Tiffert, A; Brenner, E; Marks, T

2017-03-01

Urban runoff is known to transport a significant pollutant load consisting of e.g. heavy metals, salts and hydrocarbons. Interactions between solid and dissolved compounds, proper understanding of particle size distribution, dissolved pollutant fractions and seasonal variations is crucial for the selection and development of appropriate road runoff treatment devices. Road runoff at an arterial road in Augsburg, Germany, has been studied for 3.5 years. A strong seasonal variation was observed, with increased heavy metal concentrations with doubled and tripled median concentrations for heavy metals during the cold season. Correlation analysis showed that de-icing salt is not the only factor responsible for increased pollutant concentrations in winter. During the cold period, the fraction of dissolved metals was lower compared to the warm season. In road dust, the highest metal concentrations were measured for fine particles. Metals in road runoff were found to show a significant correlation to fine particles SS63 (removal rates.

2-D model for pollutant dispersion at the coastal outfall off Paradip

Digital Repository Service at National Institute of Oceanography (India)

Suryanarayana, A.; Babu, M.T.; Vethamony, P.; Gouveia, A.D.

Simulation of dispersion of the effluent discharge has been carried out using 2-D Model to verify the advection and diffusion of the pollutant patch of the proposed effluent disposal off Paradip, Orissa, India. The simulation of dispersion...

A study of the physical factors affecting air pollution dispersion in Helwan

International Nuclear Information System (INIS)

Megahed, A.A.

1992-01-01

Air pollution is considered as one of the most important environmental problems facing the humanity. Cement industry, usually, is responsible for building high levels of pollutants. The present research focused on the study of air pollution control of cement industry using mathematical modeling. A mathematical dispersion model was developed based on Gaussian distribution where the dispersion parameters increase with increasing atmospheric turbulence. The Gaussian equation takes in consideration the effect of emission rates. stack height, buoyant plume rise, weather and meteorological parameters. The model was tested for different stack heights, wind speeds. And atmospheric stability classes. Maximum ground level concentration of cement pollutants were measured in different locations of Helwan, south Cairo around the cement factories. Analysis of results shows that the ground level of pollutants concentrations are inversely proportional to wind speed and atmospheric stability classes. Stack height also affects the behaviour of deposition of cement particulates. The model results show satisfactory agreement with the measured concentrations. 6 figs

Experimental tests of light-pollution impacts on nocturnal insect courtship and dispersal.

Science.gov (United States)

Firebaugh, Ariel; Haynes, Kyle J

2016-12-01

Though a number of effects of artificial light pollution on behavior and physiology have been described, there is little understanding of their consequences for the growth and distribution of populations. Here, we document impacts of light pollution on aspects of firefly population ecology and underlying mating behaviors. Many firefly species have a unique communication system whereby bioluminescent flashes are used in courtship displays to find and attract mates. We performed a series of manipulative field experiments in which we quantified the effects of adding artificial nighttime lighting on abundances and total flashing activity of fireflies, courtship behaviors and mating between tethered females and free-flying males, and dispersal distances of marked individuals. We show that light pollution reduces flashing activities in a dark-active firefly species (Photuris versicolor) by 69.69 % and courtship behavior and mating success in a twilight-active species (Photinus pyralis). Though courtship behavior and mating success of Photinus pyralis was reduced by light pollution, we found no effects of light pollution on male dispersal in this species. Our findings suggest that light pollution is likely to adversely impact firefly populations, and contribute to wider discussions about the ecological consequences of sensory pollution.

Atmospheric dispersion of pollutants in an industrial area of Cuba

International Nuclear Information System (INIS)

Cruz Monte de Oca, Feliberto de la; Furet Bridon, Norma Raisa; Turtos Carbonell, Leonor; Lorente Vera, Mercedes

2011-01-01

Air pollution by different chemicals; take a great connotation in the world, given the adverse effects on ecosystems and particularly human health. The urban development, the modification of the land surface and the climate change, phenomena derived from a world population explosion, are altering the composition of the air. The atmosphere deposits pollutants in the water courses and in land, which harms not only the persons, but also to the animals and the plants of the ecosystem. To know as these pollutants are dispersed in the atmosphere it is very important in the establishment of better urban, regional and world predictions of the air quality. The present study aims to assess the local spread of sulphur dioxide, nitrogen oxides and particulate matter from an industrial zone. The study was done using the pollutant Gaussian Dispersion Models AERMOD. For the evaluation of contaminants were considered two modeling scenarios: urban and rural. The SO 2 concentrations (μg/m 3 ) were obtained for 1 h, 24 h and all period (1 year), exceeding the permissible limits (500, 50 y 20 μg/m 3 ). It was also recorded for each period the number of times SO 2 concentrations exceeded the reference values in each of the scenarios discussed (urban: 39, 61 y 39; rural: 99, 75 y 25). At the end of modeling in the urban setting, 39 recipients exceeded the reference value, occupying an area of 9.75 km 2 and 25 receivers in the case of the rural setting, for an area of 6.25 km 2 . For NOx and particulate matter concentrations estimated values were always below the reference values. The obtained results in this case show the potentiality of AERMOD system for the evaluation of atmospheric dispersion of pollutants

NUMERICAL PREDICTION MODELS FOR AIR POLLUTION BY MOTOR VEHICLE EMISSIONS

Directory of Open Access Journals (Sweden)

M. M. Biliaiev

2016-12-01

Full Text Available Purpose. Scientific work involves: 1 development of 3D numerical models that allow calculating the process of air pollution by motor vehicles emissions; 2 creation of models which would allow predicting the air pollution level in urban areas. Methodology. To solve the problem upon assessing the level of air pollution by motor vehicles emissions fundamental equations of aerodynamics and mass transfer are used. For the solution of differential equations of aerodynamics and mass transfer finite-difference methods are used. For the numerical integration of the equation for the velocity potential the method of conditional approximations is applied. The equation for the velocity potential written in differential form, splits into two equations, where at each step of splitting an unknown value of the velocity potential is determined by an explicit scheme of running computation, while the difference scheme is implicit one. For the numerical integration of the emissions dispersion equation in the atmosphere applies the implicit alternating-triangular difference scheme of splitting. Emissions from the road are modeled by a series of point sources of given intensity. Developed numerical models form is the basis of the created software package. Findings. 3D numerical models were developed; they belong to the class of «diagnostic models». These models take into account main physical factors that influence the process of dispersion of harmful substances in the atmosphere when emissions from vehicles in the city occur. Based on the constructed numerical models the computational experiment was conducted to assess the level of air pollution in the street. Originality. Authors have developed numerical models that allow to calculate the 3D aerodynamics of the wind flow in urban areas and the process of mass transfer emissions from the highway. Calculations to determine the area of contamination, which is formed near the buildings, located along the highway were

Modeling of pollutant emissions from road transport; Modelisation des emissions de polluants par le transport routier

Energy Technology Data Exchange (ETDEWEB)

NONE

2003-07-01

COPERT III (computer programme to calculate emissions from road transport) is the third version of an MS Windows software programme aiming at the calculation of air pollutant emissions from road transport. COPERT estimates emissions of all regulated air pollutants (CO, NO{sub x}, VOC, PM) produced by different vehicle categories as well as CO{sub 2} emissions on the basis of fuel consumption. This research seminar was organized by the French agency of environment and energy mastery (Ademe) around the following topics: the uncertainties and sensitiveness analysis of the COPERT III model, the presentation of case studies that use COPERT III for the estimation of road transport emissions, and the future of the modeling of road transport emissions: from COPERT III to ARTEMIS (assessment and reliability of transport emission models and inventory systems). This document is a compilation of 8 contributions to this seminar and dealing with: the uncertainty and sensitiveness analysis of the COPERT III model; the road mode emissions of the ESCOMPTE program: sensitivity study; the sensitivity analysis of the spatialized traffic at the time-aggregation level: application in the framework of the INTERREG project (Alsace); the road transport aspect of the regional air quality plan of Bourgogne region: exhaustive consideration of the road network; intercomparison of tools and methods for the inventory of emissions of road transport origin; evolution of the French park of vehicles by 2025: new projections; application of COPERT III to the French context: a new version of IMPACT-ADEME; the European ARTEMIS project: new structural considerations for the modeling of road transport emissions. (J.S.)

Pollution and health risk of potentially toxic metals in urban road dust in Nanjing, a mega-city of China

International Nuclear Information System (INIS)

Liu, Enfeng; Yan, Ting; Birch, Gavin; Zhu, Yuxin

2014-01-01

Spatial variations in concentrations of a suite of potentially toxic metals (Ba, Cr, Cu, Fe, Mn, Ni, Pb and Zn) and Ca in road dusts (n = 99) from urban trunk roads (TR) in Nanjing, a mega-city in China, were established. Metal pollution levels, sources and human health risk (non-carcinogenic) were studied. In contrast to previous studies, we labeled the indicative metals relating to non-exhaust traffic emissions by comparing metal pollution between crossroad and park road dusts, and then anthropogenic sources of metals in TR dusts were assessed combining their spatial pollution patterns, principal component analysis and Pb isotopic compositions. Results showed that the metals were enriched in TR dusts compared to background soil concentrations with mean enrichment factors (EFs) of 2.2–23, indicating considerable anthropogenic influence. The degrees of metal pollution ranged from minimal to extremely high and ranked by Ca > Cu > Pb ≈ Zn > Cr ≈ Fe > Ni ≈ Ba > Mn on average. Pollution of Cr, Cu, Fe, Mn, Ni, Pb and Zn in TR dusts resulted primarily from industrial emissions (e.g., coal combustion and smelting) and high pollution levels were found close to suburb industrial complexes, whereas pollution of Ba and Ca was mainly related to construction/demolition sources and was generally distributed homogeneously. The relatively minor contribution of non-exhaust traffic emissions to metal pollution in TR dusts was considered to be due to overwhelming industrial and construction/demolition contributions, as well as to the dilution effect of natural soil particles. Ingestion appears to be the major route of exposure for road dust for both adults and children, followed by dermal contact. The non-carcinogenic health risk resulting from exposure to the potentially toxic metals in TR dusts was within the safe level based on the Hazard Index (HI), except in pollution hotspots where exposure to Pb, Cr, and Cu may be hazardous to children. - Highlights: • Pollution and

Pollution and health risk of potentially toxic metals in urban road dust in Nanjing, a mega-city of China

Energy Technology Data Exchange (ETDEWEB)

Liu, Enfeng, E-mail: efliu@niglas.ac.cn [State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008 (China); Yan, Ting [State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008 (China); Graduate University of Chinese Academy of Sciences, Beijing 100049 (China); Birch, Gavin [School of Geosciences, University of Sydney, Sydney, NSW 2006 (Australia); Zhu, Yuxin [State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008 (China)

2014-04-01

Spatial variations in concentrations of a suite of potentially toxic metals (Ba, Cr, Cu, Fe, Mn, Ni, Pb and Zn) and Ca in road dusts (n = 99) from urban trunk roads (TR) in Nanjing, a mega-city in China, were established. Metal pollution levels, sources and human health risk (non-carcinogenic) were studied. In contrast to previous studies, we labeled the indicative metals relating to non-exhaust traffic emissions by comparing metal pollution between crossroad and park road dusts, and then anthropogenic sources of metals in TR dusts were assessed combining their spatial pollution patterns, principal component analysis and Pb isotopic compositions. Results showed that the metals were enriched in TR dusts compared to background soil concentrations with mean enrichment factors (EFs) of 2.2–23, indicating considerable anthropogenic influence. The degrees of metal pollution ranged from minimal to extremely high and ranked by Ca > Cu > Pb ≈ Zn > Cr ≈ Fe > Ni ≈ Ba > Mn on average. Pollution of Cr, Cu, Fe, Mn, Ni, Pb and Zn in TR dusts resulted primarily from industrial emissions (e.g., coal combustion and smelting) and high pollution levels were found close to suburb industrial complexes, whereas pollution of Ba and Ca was mainly related to construction/demolition sources and was generally distributed homogeneously. The relatively minor contribution of non-exhaust traffic emissions to metal pollution in TR dusts was considered to be due to overwhelming industrial and construction/demolition contributions, as well as to the dilution effect of natural soil particles. Ingestion appears to be the major route of exposure for road dust for both adults and children, followed by dermal contact. The non-carcinogenic health risk resulting from exposure to the potentially toxic metals in TR dusts was within the safe level based on the Hazard Index (HI), except in pollution hotspots where exposure to Pb, Cr, and Cu may be hazardous to children. - Highlights: • Pollution and

NOx dispersion modelling around roundabout in a small city, example from Hungary

Science.gov (United States)

Farkas, Orsolya; Rákai, Anikó; Czáder, Károly; Török, Ákos

2013-04-01

The present paper focuses on the modelling of pollutant distribution and dispersion in an urban region that is located in a moderately industrialized town of Hungary, Székesfehérvár, with a population of 100,000. The study area is located close to the city centre, with different housing styles and different building elevations. High-rise buildings with 10 floors to small houses with gardens are found in the modelled area. The roundabout has 5 access roads; three major ones and two minor ones with different geometries and traffic load. The traffic load of the roads was defined by traffic count, while for the meteorological characteristics wind-statistics were created. Additional input parameters were the ground plan and the elevation of buildings. To simulate the airflow and the dispersion of pollutants a Computational Fluid Dynamics code called MISKAM was used. The background concentration was taken from the dataset of a nearby air quality monitoring station. According to vehicle counting the 5 roads of the roundabout have very different loads from 12 vehicles to more than 412 vehicles/hour. Three different grid systems were applied ranging from half million to 5 million cells. The difference in the results related to grid density was also evaluated. Wind speed distribution, wind turbulence and building wake flow patterns were identified by using the model. With the help of the simulation the NOx flow and dispersion of pollutants around the roundabout can be estimated and the critical locations with higher pollution concentration are presented. The results of the modelling can be more generalized and used in the design of the layout, development, traffic-control and environmental aspects of roundabouts located in small urban areas.

Road user charges for heavy goods vehicles (HGV):Tables with external costs of air pollution

OpenAIRE

Andersen, Mikael Skou

2013-01-01

In this report, the European Environment Agency (EEA) presents updated estimates of the external costs of air pollution for different categories of heavy goods vehicles (HGVs). This report on road transport is a continuation of previous reporting from EEA on estimates for the external costs of air pollution from industrial facilities (EEA, 2011).

Comparison of heavy metal loads in stormwater runoff from major and minor urban roads using pollutant yield rating curves

International Nuclear Information System (INIS)

Davis, Brett; Birch, Gavin

2010-01-01

Trace metal export by stormwater runoff from a major road and local street in urban Sydney, Australia, is compared using pollutant yield rating curves derived from intensive sampling data. The event loads of copper, lead and zinc are well approximated by logarithmic relationships with respect to total event discharge owing to the reliable appearance of a first flush in pollutant mass loading from urban roads. Comparisons of the yield rating curves for these three metals show that copper and zinc export rates from the local street are comparable with that of the major road, while lead export from the local street is much higher, despite a 45-fold difference in traffic volume. The yield rating curve approach allows problematic environmental data to be presented in a simple yet meaningful manner with less information loss. - A simple method for representing data onroad runoff pollution allows comparisons among dissimilar sites and could form the basis for a pollution database.

Numerical models for computation of pollutant-dispersion in the atmosphere

International Nuclear Information System (INIS)

Leder, S.M.; Biesemann-Krueger, A.

1985-04-01

The report describes some models which are used to compute the concentration of emitted pollutants in the lower atmosphere. A dispersion model, developed at the University of Hamburg, is considered in more detail and treated with two different numerical methods. The convergence of the methods is investigated and a comparison of numerical results and dispersion experiments carried out at the Nuclear Research Center Karlsruhe is given. (orig.) [de

Influence of Roads on the Surrounding Natural Environment - Vegetation, Soil, and Ground Water

Science.gov (United States)

1980-02-01

lands. The spreading of salt to combat slipperiness and to hold down the dust results in the pollution of the ground water near the highways under...Among meadow-type forests elm , ash, and alder forests are particularly sensitive to reduced water availability, while meadow-oak, meadow-beech, and... slipperiness on more heavily travelled roads (primarily K_ _ - -41- NaCi), dust-binding on gravel roads (road salt/CaClg/ and previouslv road lye

Numerical Simulation to Air Pollution Emission Control near an Industrial Zone

OpenAIRE

Oyjinda, Pravitra; Pochai, Nopparat

2017-01-01

A rapid industrial development causes several environment pollution problems. One of the main problems is air pollution, which affects human health and the environment. The consideration of an air pollutant has to focus on a polluted source. An industrial factory is an important reason that releases the air pollutant into the atmosphere. Thus a mathematical model, an atmospheric diffusion model, is used to estimate air quality that can be used to describe the sulfur dioxide dispersion. In thi...

Evaluation of Multi-Year Continuous Measurements of Ultrafine Particles at Two Near-Road Stations in Toronto, Canada

Science.gov (United States)

Su, Y.; Sofowote, U.; Debosz, J.; Munoz, T.; Whitelaw, C.

2013-12-01

Particles with an aerodynamic diameter less than 100 nanometre (nm) are referred to as ultrafine particles (UFPs). Relative to fine and course particles, UFPs have greater potential to be suspended in air for a longer time and absorb toxic chemicals due to their larger surface areas per unit mass. UFPs could penetrate deep into the respiratory or cardiovascular systems and pose adverse health effects. In urban environments, primary sources of UFPs are from road traffic emissions and account for most of the total particle numbers. Controls on UPFs rely on better understanding of their emission sources and environmental behaviour. Ontario Ministry of the Environment have monitored UFPs since 2010 at two near-road stations in Toronto by using TSI 3031 UFP monitors. The two monitoring stations are approximately 20-30 meters adjacent to major arterial roads with over 20,000 vehicles per day. UFPs concentrations were monitored using six size channels: 20-30nm, 30-50nm, 50-70nm, 70-100nm, 100-200nm, and 200-450nm. Data are collected at time intervals of 11 or 15 minutes and averaged hourly. Concurrent measurements include wind speeds, wind directions, and concentrations of other air pollutants such as nitrogen oxides and black carbon. Data influenced by road-side traffic emissions were filtered by wind direction within 45° of normal to the road and wind speed greater than 1 m/s. Number concentrations were found higher for particles with sizes of 20-30nm and 30-50nm than for other sizes of UFPs. The observed particle number distributions are generally consistent with the theoretical understanding of particle nuclei mode and accumulation mode. During the day, for UFPs with sizes of 20-30nm and 30-50nm, elevated number concentrations were observed in morning traffic hours and to a less extent in the late afternoon. The elevated UFPs number concentrations coincided with nitrogen oxides and black carbon. Moreover, higher number concentrations were found on weekdays than

Pollutant Plume Dispersion over Hypothetical Urban Areas based on Wind Tunnel Measurements

Science.gov (United States)

Mo, Ziwei; Liu, Chun-Ho

2017-04-01

Gaussian plume model is commonly adopted for pollutant concentration prediction in the atmospheric boundary layer (ABL). However, it has a number of limitations being applied to pollutant dispersion over complex land-surface morphology. In this study, the friction factor (f), as a measure of aerodynamic resistance induced by rough surfaces in the engineering community, was proposed to parameterize the vertical dispersion coefficient (σz) in the Gaussian model. A series of wind tunnel experiments were carried out to verify the mathematical hypothesis and to characterize plume dispersion as a function of surface roughness as well. Hypothetical urban areas, which were assembled in the form of idealized street canyons of different aspect (building-height-to-street-width) ratios (AR = 1/2, 1/4, 1/8 and 1/12), were fabricated by aligning identical square aluminum bars at different separation apart in cross flows. Pollutant emitted from a ground-level line source into the turbulent boundary layer (TBL) was simulated using water vapour generated by ultrasonic atomizer. The humidity and the velocity (mean and fluctuating components) were measured, respectively, by humidity sensors and hot-wire anemometry (HWA) with X-wire probes in streamwise and vertical directions. Wind tunnel results showed that the pollutant concentration exhibits the conventional Gaussian distribution, suggesting the feasibility of using water vapour as a passive scalar in wind tunnel experiments. The friction factor increased with decreasing aspect ratios (widening the building separation). It was peaked at AR = 1/8 and decreased thereafter. Besides, a positive correlation between σz/xn (x is the distance from the pollutant source) and f1/4 (correlation coefficient r2 = 0.61) was observed, formulating the basic parameterization of plume dispersion over urban areas.

Dispersion model computations of urban air pollution in Espoo, Finland

Energy Technology Data Exchange (ETDEWEB)

Valkonen, E.; Haerkoenen, J.; Kukkonen, J.; Rantakrans, E.; Jalkanen, L.

1997-12-31

This report presents the numerical results of air quality studies of the city of Espoo in southern Finland. This city is one of the four cities in the Helsinki metropolitan area, having a total population of 850 000. A thorough emission inventory was made of both mobile and stationary sources in the Helsinki metropolitan area. The atmospheric dispersion was evaluated using an urban dispersion modelling system, including a Gaussian multiple-source plume model and a meteorological pre-processing model. The hourly time series of CO, NO{sub 2} and SO{sub 2} concentrations were predicted, using the emissions and meteorological data for the year 1990. The predicted results show a clear decrease in the yearly mean concentrations from southeast to northwest. This is due in part to the denser traffic in the southern parts of Espoo, and in part to pollution from the neighbouring cities of Helsinki and Vantaa, located east of Espoo. The statistical concentration parameters found for Espoo were lower than the old national air quality guidelines (1984); however, some occurrences of above-threshold values were found for NO{sub 2} in terms of the new guidelines (1996). The contribution of traffic to the total concentrations varies spatially from 30 to 90 % for NO{sub 2} from 1 to 65 % for SO{sub 2} while for CO it is nearly 100 %. The concentrations database will be further utilised to analyse the influence of urban air pollution on the health of children attending selected day nurseries in Espoo. The results of this study can also be applied in traffic and city planning. In future work the results will also be compared with data from the urban measurement network of the Helsinki Metropolitan Area Council. (orig.) 19 refs.

Inventory of conventional air pollutants emissions from road transportation for the state of Rio de Janeiro

International Nuclear Information System (INIS)

Souza, Cristiane Duarte Ribeiro de; Silva, Suellem Deodoro; Silva, Marcelino Aurélio Vieira da; D’Agosto, Márcio de Almeida; Barboza, Arthur Prado

2013-01-01

Road transportation has contributed to increased emissions of conventional air pollutants and, consequently, to the increase in problems associated with the environment and human health, depending on the type of pollutant and the concentration of it. To support the development of public policies aimed to decrease total tonnes of emissions, we used a bottom-up approach to estimate the amount of air pollutants, such as carbon monoxide (CO), total hydrocarbons (THC), nitrogen oxides (NO x ), particulate matter (PM), and aldehydes (RCHO), that are emitted by road transportation in the state of Rio de Janeiro (RJ) from 1980 to 2010. The results from 2010 show that cars are responsible for 55% of CO emissions, 61% of THC emissions, and 93% of RCHO emissions. Due to the use of hydrated ethanol and compressed natural gas (CNG) instead of petroleum based fuels during the period analyzed, 1,760,370 t of air pollutant emissions were avoided. Compared to Brazil, in 2010, RJ had a quantity of emissions per vehicle from 12% (CO) to 59% (PM) smaller than the national average. As strategies to reduce air pollutant emissions, we consider reducing the intensity of use, with a proportional reduction in emissions, and increased the use of biodiesel. - Highlights: ► We estimate road transportation emissions for Rio de Janeiro from 1980 to 2010. ► C gasoline was most responsible for CO (74%) and diesel for PM (91%). ► Emissions/vehicle for Rio de Janeiro are (12% to 59%) smaller than Brazilian. ► 1,760,370 t of emissions was avoided using non-petroleum-based fuels. ► Strategies to reduce the emissions of these air pollutants were proposed.

Noise pollution alters ecological services: enhanced pollination and disrupted seed dispersal.

Science.gov (United States)

Francis, Clinton D; Kleist, Nathan J; Ortega, Catherine P; Cruz, Alexander

2012-07-22

Noise pollution is a novel, widespread environmental force that has recently been shown to alter the behaviour and distribution of birds and other vertebrates, yet whether noise has cumulative, community-level consequences by changing critical ecological services is unknown. Herein, we examined the effects of noise pollution on pollination and seed dispersal and seedling establishment within a study system that isolated the effects of noise from confounding stimuli common to human-altered landscapes. Using observations, vegetation surveys and pollen transfer and seed removal experiments, we found that effects of noise pollution can reverberate through communities by disrupting or enhancing these ecological services. Specifically, noise pollution indirectly increased artificial flower pollination by hummingbirds, but altered the community of animals that prey upon and disperse Pinus edulis seeds, potentially explaining reduced P. edulis seedling recruitment in noisy areas. Despite evidence that some ecological services, such as pollination, may benefit indirectly owing to noise, declines in seedling recruitment for key-dominant species such as P. edulis may have dramatic long-term effects on ecosystem structure and diversity. Because the extent of noise pollution is growing, this study emphasizes that investigators should evaluate the ecological consequences of noise alongside other human-induced environmental changes that are reshaping human-altered landscapes worldwide.

Noise pollution alters ecological services: enhanced pollination and disrupted seed dispersal

Science.gov (United States)

Francis, Clinton D.; Kleist, Nathan J.; Ortega, Catherine P.; Cruz, Alexander

2012-01-01

Noise pollution is a novel, widespread environmental force that has recently been shown to alter the behaviour and distribution of birds and other vertebrates, yet whether noise has cumulative, community-level consequences by changing critical ecological services is unknown. Herein, we examined the effects of noise pollution on pollination and seed dispersal and seedling establishment within a study system that isolated the effects of noise from confounding stimuli common to human-altered landscapes. Using observations, vegetation surveys and pollen transfer and seed removal experiments, we found that effects of noise pollution can reverberate through communities by disrupting or enhancing these ecological services. Specifically, noise pollution indirectly increased artificial flower pollination by hummingbirds, but altered the community of animals that prey upon and disperse Pinus edulis seeds, potentially explaining reduced P. edulis seedling recruitment in noisy areas. Despite evidence that some ecological services, such as pollination, may benefit indirectly owing to noise, declines in seedling recruitment for key-dominant species such as P. edulis may have dramatic long-term effects on ecosystem structure and diversity. Because the extent of noise pollution is growing, this study emphasizes that investigators should evaluate the ecological consequences of noise alongside other human-induced environmental changes that are reshaping human-altered landscapes worldwide. PMID:22438504

More efforts needed to curb air pollution caused by road transport

International Nuclear Information System (INIS)

Ba, M.; Traimany, A.

2001-09-01

In France, road transport is the main source of pollutant emissions in urban areas despite a fall in emissions of certain pollutants, recently achieved following significant technological progress and new legislation adopted. In addition, CO 2 emissions from motor vehicles continue to rise, accounting for about 40 % of net CO 2 emissions in France. These trends are mainly due to consumer behaviour and the use of motor vehicles. The sharp increase in passenger and freight traffic and an increase in the distances covered have negative impacts on the environment. In light of this situation, new technologies appear to be an inadequate solution to reverse emission trends. (A.L.B.)

Identification and elucidation of anthropogenic source contribution in PM10 pollutant: Insight gain from dispersion and receptor models.

Science.gov (United States)

Roy, Debananda; Singh, Gurdeep; Yadav, Pankaj

2016-10-01

Source apportionment study of PM 10 (Particulate Matter) in a critically polluted area of Jharia coalfield, India has been carried out using Dispersion model, Principle Component Analysis (PCA) and Chemical Mass Balance (CMB) techniques. Dispersion model Atmospheric Dispersion Model (AERMOD) was introduced to simplify the complexity of sources in Jharia coalfield. PCA and CMB analysis indicates that monitoring stations near the mining area were mainly affected by the emission from open coal mining and its associated activities such as coal transportation, loading and unloading of coal. Mine fire emission also contributed a considerable amount of particulate matters in monitoring stations. Locations in the city area were mostly affected by vehicular, Liquid Petroleum Gas (LPG) & Diesel Generator (DG) set emissions, residential, and commercial activities. The experimental data sampling and their analysis could aid understanding how dispersion based model technique along with receptor model based concept can be strategically used for quantitative analysis of Natural and Anthropogenic sources of PM 10 . Copyright © 2016. Published by Elsevier B.V.

A vegetation modeling concept for Building and Environmental Aerodynamics wind tunnel tests and its application in pollutant dispersion studies

International Nuclear Information System (INIS)

Gromke, Christof

2011-01-01

A new vegetation modeling concept for Building and Environmental Aerodynamics wind tunnel investigations was developed. The modeling concept is based on fluid dynamical similarity aspects and allows the small-scale modeling of various kinds of vegetation, e.g. field crops, shrubs, hedges, single trees and forest stands. The applicability of the modeling concept was validated in wind tunnel pollutant dispersion studies. Avenue trees in urban street canyons were modeled and their implications on traffic pollutant dispersion were investigated. The dispersion experiments proved the modeling concept to be practicable for wind tunnel studies and suggested to provide reliable concentration results. Unfavorable effects of trees on pollutant dispersion and natural ventilation in street canyons were revealed. Increased traffic pollutant concentrations were found in comparison to the tree-free reference case. - Highlights: → A concept for aerodynamic modelling of vegetation in small scale wind tunnel studies is presented. → The concept was applied to study pollutant dispersion in urban street canyons with avenue tress. → The wind tunnel studies show that modelling the aerodynamic effects of vegetation is important. → Avenue trees give rise to increased pollutant concentrations in urban street canyons. - Avenue trees in urban street canyons affect the pollutant dispersion and result in increased traffic exhaust concentrations.

Multiple evaluations of the removal of pollutants in road runoff by soil infiltration.

Science.gov (United States)

Murakami, Michio; Sato, Nobuyuki; Anegawa, Aya; Nakada, Norihide; Harada, Arata; Komatsu, Toshiya; Takada, Hideshige; Tanaka, Hiroaki; Ono, Yoshiro; Furumai, Hiroaki

2008-05-01

Groundwater replenishment by infiltration of road runoff is expected to be a promising option for ensuring a sustainable urban water cycle. In this study, we performed a soil infiltration column test using artificial road runoff equivalent to approximately 11-12 years of rainfall to evaluate the removal of pollutants by using various chemical analyses and bioassay tests. These results indicated that soil infiltration treatment works effectively to remove most of the pollutants such as organic matter (chemical oxygen demand (CODMn) and dissolved organic carbon (DOC)), P species, polycyclic aromatic hydrocarbons (PAHs), numerous heavy metals and oestrogenic activities. Bioassay tests, including algal growth inhibition test, Microtox and mutagen formation potential (MFP) test, also revealed effective removal of toxicities by the soils. However, limited amounts of NO3, Mn, Ni, alkaline earth metals, perfluorooctane sulphonate (PFOS) and perfluorooctane sulphonamide (FOSA) were removed by the soils and they possibly reach the groundwater and cause contamination.

Inroads into Equestrian Safety: Rider-Reported Factors Contributing to Horse-Related Accidents and Near Misses on Australian Roads

Science.gov (United States)

Thompson, Kirrilly; Matthews, Chelsea

2015-01-01

Simple Summary Riding horses on roads can be dangerous, but little is known about accidents and near misses. To explore road safety issues amongst Australian equestrians, we conducted an online survey. More than half of all riders (52%) reported having experienced at least one accident or near miss in the 12 months prior to the survey, mostly attributed to speed. Whilst our findings confirmed factors identified overseas, we also identified issues around road rules, hand signals and road rage. This paper suggests strategies for improving the safety of horses, riders and other road users. Abstract Horse riding and horse-related interactions are inherently dangerous. When they occur on public roads, the risk profile of equestrian activities is complicated by interactions with other road users. Research has identified speed, proximity, visibility, conspicuity and mutual misunderstanding as factors contributing to accidents and near misses. However, little is known about their significance or incidence in Australia. To explore road safety issues amongst Australian equestrians, we conducted an online survey. More than half of all riders (52%) reported having experienced at least one accident or near miss in the 12 months prior to the survey. Whilst our findings confirm the factors identified overseas, we also identified issues around rider misunderstanding of road rules and driver misunderstanding of rider hand signals. Of particular concern, we also found reports of potentially dangerous rider-directed road rage. We identify several areas for potential safety intervention including (1) identifying equestrians as vulnerable road users and horses as sentient decision-making vehicles; (2) harmonising laws regarding passing horses; (3) mandating personal protective equipment; (4) improving road signage; (5) comprehensive data collection; (6) developing mutual understanding amongst road-users; (7) safer road design and alternative riding spaces; and (8) increasing investment

Overview of the Brooklyn traffic real-time ambient pollutant penetration and environmental dispersion (B-TRAPPED) study: theoretical background and model for design of field experiments.

Science.gov (United States)

Hahn, Intaek; Wiener, Russell W; Richmond-Bryant, Jennifer; Brixey, Laurie A; Henkle, Stacy W

2009-12-01

The Brooklyn traffic real-time ambient pollutant penetration and environmental dispersion (B-TRAPPED) study was a multidisciplinary field research project that investigated the transport, dispersion, and infiltration processes of traffic emission particulate matter (PM) pollutants in a near-highway urban residential area. The urban PM transport, dispersion, and infiltration processes were described mathematically in a theoretical model that was constructed to develop the experimental objectives of the B-TRAPPED study. In the study, simultaneous and continuous time-series PM concentration and meteorological data collected at multiple outdoor and indoor monitoring locations were used to characterize both temporal and spatial patterns of the PM concentration movements within microscale distances (street canyon; (2) investigating the effects of urban structures such as a tall building or an intersection on the transport and dispersion of PM; (3) studying the influence of meteorological variables on the transport, dispersion, and infiltration processes; (4) characterizing the relationships between the building parameters and the infiltration mechanisms; (5) establishing a cause-and-effect relationship between outdoor-released PM and indoor PM concentrations and identifying the dominant mechanisms involved in the infiltration process; (6) evaluating the effectiveness of a shelter-in-place area for protection against outdoor-released PM pollutants; and (7) understanding the predominant airflow and pollutant dispersion patterns within the neighborhood using wind tunnel and CFD simulations. The 10 papers in this first set of papers presenting the results from the B-TRAPPED study address these objectives. This paper describes the theoretical background and models representing the interrelated processes of transport, dispersion, and infiltration. The theoretical solution for the relationship between the time-dependent indoor PM concentration and the initial PM concentration

Magnetic susceptibility of road deposited sediments at a national scale – Relation to population size and urban pollution

International Nuclear Information System (INIS)

Jordanova, Diana; Jordanova, Neli; Petrov, Petar

2014-01-01

Magnetic properties of road dusts from 26 urban sites in Bulgaria are studied. Temporal variations of magnetic susceptibility (χ) during eighteen months monitoring account for approximately 1/3rd of the mean annual values. Analysis of heavy metal contents and magnetic parameters for the fraction d  2  = −0.84) is observed between the ratio ARM/χ and Pb content. It suggests that Pb is related to brake/tyre wear emissions, releasing larger particles and higher Pb during slow driving – braking. Bulk χ values of road dusts per city show significant correlation with population size and mean annual NO 2 concentration on a log-normal scale. The results demonstrate the applicability of magnetic measurements of road dusts for estimation of mean NO 2 levels at high spatial density, which is important for pollution modelling and health risk assessment. - Highlights: • temporal variations of road dust magnetic susceptibility comprise 1/3 of the signal. • high negative correlation between Pb content and magnetic ratio ARM/χ is obtained. • brake- and tyre ware emissions are the main pollution sources of the road dusts. • road dust magnetic susceptibility rises parallel with logarithm of population size. • linear correlation is found between mean NO 2 concentrations and susceptibility. - Magnetic susceptibility of road dusts on a national scale increases proportionally to the population size and mean NO 2 concentrations due to the effect of traffic related pollution

CFD modelling of the aerodynamic effect of trees on urban air pollution dispersion.

Science.gov (United States)

Amorim, J H; Rodrigues, V; Tavares, R; Valente, J; Borrego, C

2013-09-01

The current work evaluates the impact of urban trees over the dispersion of carbon monoxide (CO) emitted by road traffic, due to the induced modification of the wind flow characteristics. With this purpose, the standard flow equations with a kε closure for turbulence were extended with the capability to account for the aerodynamic effect of trees over the wind field. Two CFD models were used for testing this numerical approach. Air quality simulations were conducted for two periods of 31h in selected areas of Lisbon and Aveiro, in Portugal, for distinct relative wind directions: approximately 45° and nearly parallel to the main avenue, respectively. The statistical evaluation of modelling performance and uncertainty revealed a significant improvement of results with trees, as shown by the reduction of the NMSE from 0.14 to 0.10 in Lisbon, and from 0.14 to 0.04 in Aveiro, which is independent from the CFD model applied. The consideration of the plant canopy allowed to fulfil the data quality objectives for ambient air quality modelling established by the Directive 2008/50/EC, with an important decrease of the maximum deviation between site measurements and CFD results. In the non-aligned wind situation an average 12% increase of the CO concentrations in the domain was observed as a response to the aerodynamic action of trees over the vertical exchange rates of polluted air with the above roof-level atmosphere; while for the aligned configuration an average 16% decrease was registered due to the enhanced ventilation of the street canyon. These results show that urban air quality can be optimised based on knowledge-based planning of green spaces. Copyright © 2013 Elsevier B.V. All rights reserved.

Characterization of non point source pollutants and their dispersion ...

African Journals Online (AJOL)

EJIRO

landing site in Uganda. N. Banadda. Agricultural and Bio-Systems Engineering Department, Makerere University, P. O. Box 7062, Kampala, Uganda. E-mail: banadda@agric.mak.ac.ug. Fax: +256-414-53.16.41. Accepted 5 January, 2011. The aim of this research is to characterize non point pollutants and their dispersion in ...

DETECTION RELEVANCY OF SOME FACTORS INFLUENCING ON AIR POLLUTION FROM AUTOMOBILE AND ROAD COMPLEX

Directory of Open Access Journals (Sweden)

Radkevich, M.

2013-01-01

Full Text Available The dependence between the pavement evenness and the emissions of air pollutants from automobile – road sector is detected. It is proposed to take the pavement evenness for the assessment criterion of greenhouse and other gases emissions.

[Risk for environment-induced diseases due to air pollution from motor vehicles in road-patrol officers].

Science.gov (United States)

Mikhaĭlichenko, K Iu; Kas'ianenko, A A; Shchelkunova, I G; Grechko, A V

2010-01-01

The paper describes risk factors for environment-induced diseases in road-patrol (RP) officers under the existing working conditions: noise and chemical ambient air pollution from motor vehicles. There is evidence for a significant increase in the incidence of diseases of the cardiovascular and nervous system, sense organs, digestive and endocrine metabolic systems in the State Road Safety Inspectorate officers who are directly engaged in traffic management. Potential and real risks from motor transport to the health of RP roads have been estimated. Recommendations on optimizing the working conditions are given.

Parametric laws to model urban pollutant dispersion with a street network approach

Science.gov (United States)

Soulhac, L.; Salizzoni, P.; Mejean, P.; Perkins, R. J.

2013-03-01

This study discusses the reliability of the street network approach for pollutant dispersion modelling in urban areas. This is essentially based on a box model, with parametric relations that explicitly model the main phenomena that contribute to the street canyon ventilation: the mass exchanges between the street and the atmosphere, the pollutant advection along the street axes and the pollutant transfer at street intersections. In the first part of the paper the focus is on the development of a model for the bulk transfer street/atmosphere, which represents the main ventilation mechanisms for wind direction that are almost perpendicular to the axis of the street. We then discuss the role of the advective transfer along the street axis on its ventilation, depending on the length of the street and the direction of the external wind. Finally we evaluate the performances of a box model integrating parametric exchange laws for these transfer phenomena. To that purpose we compare the prediction of the model to wind tunnel experiments of pollutant dispersion within a street canyon placed in an idealised urban district.

Characteristics of flow and reactive pollutant dispersion in urban street canyons

Science.gov (United States)

Park, Soo-Jin; Kim, Jae-Jin; Kim, Minjoong J.; Park, Rokjin J.; Cheong, Hyeong-Bin

2015-05-01

In this study, the effects of aspect ratio defined as the ratio of building height to street width on the dispersion of reactive pollutants in street canyons were investigated using a coupled CFD-chemistry model. Flow characteristics for different aspect ratios were analyzed first. For each aspect ratio, six emission scenarios with different VOC-NOX ratios were considered. One vortex was generated when the aspect ratio was less than 1.6 (shallow street canyon). When the aspect ratio was greater than 1.6 (deep street canyon), two vortices were formed in the street canyons. Comparing to previous studies on two-dimensional street canyons, the vortex center is slanted toward the upwind building and reverse and downward flows are dominant in street canyons. Near the street bottom, there is a marked difference in flow pattern between in shallow and deep street canyons. Near the street bottom, reverse and downward flows are dominant in shallow street canyon and flow convergence exists near the center of the deep street canyons, which induces a large difference in the NOX and O3 dispersion patterns in the street canyons. NOX concentrations are high near the street bottom and decreases with height. The O3 concentrations are low at high NO concentrations near the street bottom because of NO titration. At a low VOC-NOX ratio, the NO concentrations are sufficiently high to destroy large amount of O3 by titration, resulting in an O3 concentration in the street canyon much lower than the background concentration. At high VOC-NOX ratios, a small amount of O3 is destroyed by NO titration in the lower layer of the street canyons. However, in the upper layer, O3 is formed through the photolysis of NO2 by VOC degradation reactions. As the aspect ratio increases, NOX (O3) concentrations averaged over the street canyons decrease (increase) in the shallow street canyons. This is because outward flow becomes strong and NOX flux toward the outsides of the street canyons increases

Effects of canyon geometry on the distribution of traffic-related air pollution in a large urban area: Implications of a multi-canyon air pollution dispersion model

Science.gov (United States)

Fu, Xiangwen; Liu, Junfeng; Ban-Weiss, George A.; Zhang, Jiachen; Huang, Xin; Ouyang, Bin; Popoola, Olalekan; Tao, Shu

2017-09-01

Street canyons are ubiquitous in urban areas. Traffic-related air pollutants in street canyons can adversely affect human health. In this study, an urban-scale traffic pollution dispersion model is developed considering street distribution, canyon geometry, background meteorology, traffic assignment, traffic emissions and air pollutant dispersion. In the model, vehicle exhausts generated from traffic flows first disperse inside street canyons along the micro-scale wind field generated by computational fluid dynamics (CFD) model. Then, pollutants leave the street canyon and further disperse over the urban area. On the basis of this model, the effects of canyon geometry on the distribution of NOx and CO from traffic emissions were studied over the center of Beijing. We found that an increase in building height leads to heavier pollution inside canyons and lower pollution outside canyons at pedestrian level, resulting in higher domain-averaged concentrations over the area. In addition, canyons with highly even or highly uneven building heights on each side of the street tend to lower the urban-scale air pollution concentrations at pedestrian level. Further, increasing street widths tends to lead to lower pollutant concentrations by reducing emissions and enhancing ventilation simultaneously. Our results indicate that canyon geometry strongly influences human exposure to traffic pollutants in the populated urban area. Carefully planning street layout and canyon geometry while considering traffic demand as well as local weather patterns may significantly reduce inhalation of unhealthy air by urban residents.

Road traffic impact on urban water quality: a step towards integrated traffic, air and stormwater modelling.

Science.gov (United States)

Fallah Shorshani, Masoud; Bonhomme, Céline; Petrucci, Guido; André, Michel; Seigneur, Christian

2014-04-01

Methods for simulating air pollution due to road traffic and the associated effects on stormwater runoff quality in an urban environment are examined with particular emphasis on the integration of the various simulation models into a consistent modelling chain. To that end, the models for traffic, pollutant emissions, atmospheric dispersion and deposition, and stormwater contamination are reviewed. The present study focuses on the implementation of a modelling chain for an actual urban case study, which is the contamination of water runoff by cadmium (Cd), lead (Pb), and zinc (Zn) in the Grigny urban catchment near Paris, France. First, traffic emissions are calculated with traffic inputs using the COPERT4 methodology. Next, the atmospheric dispersion of pollutants is simulated with the Polyphemus line source model and pollutant deposition fluxes in different subcatchment areas are calculated. Finally, the SWMM water quantity and quality model is used to estimate the concentrations of pollutants in stormwater runoff. The simulation results are compared to mass flow rates and concentrations of Cd, Pb and Zn measured at the catchment outlet. The contribution of local traffic to stormwater contamination is estimated to be significant for Pb and, to a lesser extent, for Zn and Cd; however, Pb is most likely overestimated due to outdated emissions factors. The results demonstrate the importance of treating distributed traffic emissions from major roadways explicitly since the impact of these sources on concentrations in the catchment outlet is underestimated when those traffic emissions are spatially averaged over the catchment area.

Assessment of Air Pollution Tolerance Index of some plants to develop vertical gardens near street canyons of a polluted tropical city.

Science.gov (United States)

Pandey, Ashutosh Kumar; Pandey, Mayank; Tripathi, B D

2016-12-01

The aim of the present study was to examine Air Pollution Tolerance Index (APTI) of some climber plant species to develop vertical gardens in Varanasi city which has characteristics of tall building and narrow roads. This condition results in street canyon like structure and hinders the vertical dispersal of air pollutants. We have selected 24 climber plant species which are commonly found in of Varanasi city. Chosen plants can be easily grown either in planter boxes or directly in the ground, with a vertical support they can climb on walls to form green walls or vertical garden. Air Pollution Tolerance Index (APTI) of the selected plant species was calculated and plants with higher APTI are recommended for the development of Vertical garden. Highest APTI was noted for Ipomoea palmata (25.39) followed by Aristolochia elegans (23.28), Thunbergia grandiflora (23.14), Quisqualis indica (22.42), and Clerodendrum splendens (22.36). However, lowest APTI value (8.75) was recorded for the species Hemidesmus indicus. Moreover, the linear regression analysis has revealed a high positive correlation between APTI and ascorbic acid content (R 2 =0.8837) and positive correlation between APTI and Chlorophyll content (R 2 =0.6687). On the basis of higher APTI values (greater than 17), nine species of climber plants viz. I. palmata, T. grandiflora, C. splendens, A. elegans, Q. indica, Petria volubilis, Antigonon leptopus, Cryptolepis buchuanni and Tinospora cordifolia have been recommended to develop vertical greenery systems in a compact tropical city. Copyright © 2015 Elsevier Inc. All rights reserved.

Dispersion of pollutants, environmental externalities due to a pulverized coal power plant and their effect on the cost of electricity

International Nuclear Information System (INIS)

Czarnowska, Lucyna; Frangopoulos, Christos A.

2012-01-01

Energy conversion systems generate pollution that causes damages to the environment and the society. The objective of this work is to study the dispersion of pollutants and assess the environmental and social cost due to pollution from such a system. For this purpose, a pulverized coal power plant is selected. Using thermodynamic principles combined with empirical techniques, the quantities of pollutants emitted by the plant are estimated. Then, using the EcoSenseWeb software, which is based on the results of the ExternE project, the external environmental cost (externalities) of pollution is assessed. The plant is considered as located in four different cities in Poland and the externalities are calculated for each city separately. It is shown that the external environmental cost has a strong influence on the unit cost of electricity. In addition, the dispersion of pollutants is presented for the plant located in Olsztyn city. Furthermore, the plant is considered as located near the capitals of European countries and the environmental externalities are calculated for each city. The neighboring countries that are strongly affected by the plant in each particular city are identified. The sensitivity of the unit cost of electricity to certain important parameters is investigated. -- Highlights: ► The external cost of pollution has a significant impact on the cost of electricity. ► The results depend on the particular plant, location and level (local-global). ► Externalities make the installation of abatement equipment economical. ► The source location of emissions has a significant effect on the external cost. ► The transboundary pollution has a strong effect on the environmental cost.

Long-termexposure to road traffic noise, ambient air pollution, and cardiovascular risk factors in the HUNT and lifelines cohorts

NARCIS (Netherlands)

Cai, Yutong; Hansell, Anna L.; Blangiardo, Marta; Burton, Paul R.; de Hoogh, Kees; Doiron, Dany; Fortier, Isabel; Gulliver, John; Hveem, Kristian; Mbatchou, Stéphane; Morley, DavidW.; Stolk, Ronald P.; Zijlema, Wilma L.; Elliott, Paul; Hodgson, Susan

2017-01-01

Aims: Blood biochemistry may provide information on associations between road traffic noise, air pollution, and cardiovascular disease risk. We evaluated this in two large European cohorts (HUNT3, Lifelines). Methods and results: Road traffic noise exposure was modelled for 2009 using a simplified

Polybrominated diphenyl ethers in road and farmland soils from an e-waste recycling region in Southern China: Concentrations, source profiles, and potential dispersion and deposition

International Nuclear Information System (INIS)

Luo Yong; Luo Xiaojun; Lin Zhen; Chen Shejun; Liu Juan; Mai Bixian; Yang Zhongyi

2009-01-01

The present study analyzed road soils collected near the dismantling workshops of an e-waste recycling region in South China to determine the PBDE profiles. Farmland soils at a distance of about 2 km from the dismantling workshops were also collected to evaluate the potential dispersion and deposition of PBDEs in the surrounding environment. Total PBDE concentrations ranged from 191 to 9156 ng/g dry weight in road soils and from 2.9 to 207 ng/g dry weight in farmland soils, respectively. Three PBDE source profiles were observed from the road soils by principal component analysis, and were compared with the congener patterns in different technical products. Elevated abundances of octa- and nona-congeners were found in the 'deca-' derived PBDEs as compared with the deca-BDE products. The results in this study suggest that debromination of BDE 209 may have occurred during the use of electric and electronic equipment and/or another technical formulation (Bromkal 79-8DE) was also likely the source of octa- and nona-congeners in e-wastes. Comparison of the PBDE patterns in road and farmland soils implied that the PBDEs in farmland soils have been subject to complex environmental processes

Experimental and numerical study of atmospheric turbulence and dispersion in stable conditions and in near field at a complex site

International Nuclear Information System (INIS)

Wei, Xiao

2016-01-01

An experimental program has been designed in order to study pollutants dispersion at a complex site with a focus on stable conditions, which are still challenging for numerical modelling. This experimental program is being conducted at the SIRTA site in a southern suburb of Paris and consists in measuring, in near field, the turbulence and the pollutants dispersion. The aim of this program is to characterize the fine structure of turbulence and associated dispersion through high temporal and spatial resolution measurements. Then, these measurements allow to validate and improve the performance of CFD simulation for turbulence and dispersion in a heterogeneous field. The instrumental set up includes 12 ultrasonic anemometers measuring continuously wind velocity and temperature at 10 Hz, and 6 photo-ionization detectors (PIDs) measuring gas concentration at 50 Hz during tracer tests. Intensive observations periods (IOPs) with gas releases have been performed since March 2012. First of all, a detailed study of flow on the site is made, because it must be characterised and properly simulated before attempting to simulate the pollutants dispersion. This study is based on two years of continuous measurements and on measurements performed during IOPs. Turbulence strong anisotropy in the surface layer is characterized by calculating variances, integral length scales and power spectra of the three wind velocity components. Propagation of turbulent structures between sensors has been characterized with velocity correlations. Energy spectra show several slopes in different frequency regions. Also, data analyses show impact of terrain heterogeneity on the measurements. The forest to the north of the experimental field modifies wind velocity and direction for a large northerly sector. It induces a strong directional wind shear and a wind deceleration below the forest height. Numerical simulations are carried out using the CFD code, Code-Saturne, in RANS mode with a standard k

Experimental and numerical study of atmospheric turbulence and dispersion in stable conditions and in near field at a complex site

International Nuclear Information System (INIS)

Wei, Xiao

2016-01-01

An experimental program has been designed in order to study pollutants dispersion at a complex site with a focus on stable conditions, which are still challenging for numerical modelling. This experimental program is being conducted at the SIRTA site in a southern suburb of Paris and consists in measuring, in near field, the turbulence and the pollutants dispersion. The aim of this program is to characterize the fine structure of turbulence and associated dispersion through high temporal and spatial resolution measurements. Then, these measurements allow to validate and improve the performance of CFD simulation for turbulence and dispersion in a heterogeneous field. The instrumental set up includes 12 ultrasonic anemometers measuring continuously wind velocity and temperature at 10 Hz, and 6 photo-ionization detectors (PIDs) measuring gas concentration at 50 Hz during tracer tests. Intensive observations periods (IOPs) with gas releases have been performed since March 2012.First of all, a detailed study of flow on the site is made, because it must be characterised and properly simulated before attempting to simulate the pollutants dispersion. This study is based on two years of continuous measurements and on measurements performed during IOPs. Turbulence strong anisotropy in the surface layer is characterized by calculating variances, integral length scales and power spectra of the three wind velocity components. Propagation of turbulent structures between sensors has been characterized with velocity correlations. Energy spectra show several slopes in different frequency regions. Also, data analyses show impact of terrain heterogeneity on the measurements. The forest to the north of experimental field modifies wind velocity and direction for a large northerly sector. It induces a strong directional wind shear and a wind deceleration below the forest height. Numerical simulations are carried out using the CFD code Code-Saturne in RANS mode with a standard κ

Air Pollution Dispersion Modeling of Abadan oil Refinery Using SCREEN3

International Nuclear Information System (INIS)

Hedayati Rad, F.; Salman-Mahini, A.; Mirkarimi, H.

2016-01-01

Air pollution is a major problem that has been recognized throughout the world. Refineriers normally create environmental pollution through emissions of pollutants gaseous from a variety of sources. Analysing air pollution distribution and dispersion can help in reducing the negative effects. In this study NO_X and SO_2 emissions and distributions were investigated for Abadan oil refinery using SCREEN3 software. In this softweare, wind speed and direction, air temperature, location and physical characteristics of chimnies and atmospheric stability were taken into consideration.The concentration of pollutants in different distances from the stacks in the range 25 km were predicted and mapped in Idrisi software. The output from software SCREEN3 for emissions from stacks were also examined and compared with the standard output of the refineries. According to our results, the concentration of pollutants in summer and autumn seasons exceeds of the environmental standards.

Impact of London's road traffic air and noise pollution on birth weight: retrospective population based cohort study.

Science.gov (United States)

Smith, Rachel B; Fecht, Daniela; Gulliver, John; Beevers, Sean D; Dajnak, David; Blangiardo, Marta; Ghosh, Rebecca E; Hansell, Anna L; Kelly, Frank J; Anderson, H Ross; Toledano, Mireille B

2017-12-05

Objective  To investigate the relation between exposure to both air and noise pollution from road traffic and birth weight outcomes. Design  Retrospective population based cohort study. Setting  Greater London and surrounding counties up to the M25 motorway (2317 km 2 ), UK, from 2006 to 2010. Participants  540 365 singleton term live births. Main outcome measures  Term low birth weight (LBW), small for gestational age (SGA) at term, and term birth weight. Results  Average air pollutant exposures across pregnancy were 41 μg/m 3 nitrogen dioxide (NO 2 ), 73 μg/m 3 nitrogen oxides (NO x ), 14 μg/m 3 particulate matter with aerodynamic diameter noise levels were 58 dB and 53 dB respectively. Interquartile range increases in NO 2 , NO x , PM 2.5 , PM 10 , and source specific PM 2.5 from traffic exhaust (PM 2.5 traffic exhaust ) and traffic non-exhaust (brake or tyre wear and resuspension) (PM 2.5 traffic non-exhaust ) were associated with 2% to 6% increased odds of term LBW, and 1% to 3% increased odds of term SGA. Air pollutant associations were robust to adjustment for road traffic noise. Trends of decreasing birth weight across increasing road traffic noise categories were observed, but were strongly attenuated when adjusted for primary traffic related air pollutants. Only PM 2.5 traffic exhaust and PM 2.5 were consistently associated with increased risk of term LBW after adjustment for each of the other air pollutants. It was estimated that 3% of term LBW cases in London are directly attributable to residential exposure to PM 2.5 >13.8 μg/m 3 during pregnancy. Conclusions  The findings suggest that air pollution from road traffic in London is adversely affecting fetal growth. The results suggest little evidence for an independent exposure-response effect of traffic related noise on birth weight outcomes. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

A Comparison of Exposure Metrics for Traffic-Related Air Pollutants: Application to Epidemiology Studies in Detroit, Michigan

Science.gov (United States)

Vehicles are major sources of air pollutant emissions, and individuals living near large roads endure high exposures and health risks associated with traffic-related air pollutants. Air pollution epidemiology, health risk, environmental justice, and transportation planning studi...

Economic impacts from PM2.5 pollution-related health effects in China's road transport sector: A provincial-level analysis.

Science.gov (United States)

Tian, Xu; Dai, Hancheng; Geng, Yong; Wilson, Jeffrey; Wu, Rui; Xie, Yang; Hao, Han

2018-06-01

Economic impact assessments of air pollution-related health effects from a sectoral perspective in China is still deficient. This study evaluates the PM 2.5 pollution-related health impacts of the road transport sector on China's economy at both national and provincial levels in 2030 under various air mitigation technologies scenarios. Health impacts are estimated using an integrated approach that combines the Greenhouse Gas and Air Pollution Interactions and Synergies (GAINS) model, a computable general equilibrium (CGE) model and a health model. Results show that at a national level, the road transport sector leads to 163.64 thousand deaths per year, increases the per capita risk of morbidity by 0.37% and accounts for 1.43 billion Yuan in health care expenditures. We estimate 442.90 billion Yuan of the value of statistical life loss and 2.09 h/capita of work time loss in 2015. Without additional control measures, air pollution related to the transport sector will cause 177.50 thousand deaths in 2030, a 0.40% per capita increase in the risk of morbidity, accounting for 4.12 billion Yuan in health care expenditures, 737.15 billion Yuan of statistical life loss and 2.23 h/capita of work time loss. Based on our model, implementing the most strict control strategy scenario would decrease mortality by 42.14%, morbidity risk by 42.14%, health care expenditures by 41.94%, statistical life loss by 26.22% and hours of work time loss by 42.65%, comparing with the no control measure scenario. In addition, PM 2.5 pollution from the road transport sector will cause 0.68% GDP loss in 2030. At a provincial level, GDP losses in 14 out of 30 provinces far exceed the national rate. Henan (1.20%), Sichuan (1.07%), Chongqing (0.99%), Hubei (0.94%), and Shandong (0.90%) would experience the highest GDP loss in 2030. Implementing control strategies to reduce PM 2.5 pollution in the road transport sector could bring positive benefits in half of the Chinese provinces especially in

Air Pollution Modeling at Road Sides Using the Operational Street Pollution Model-A Case Study in Hanoi, Vietnam

DEFF Research Database (Denmark)

Hung, Ngo Tho; Ketzel, Matthias; Jensen, Steen Solvang

2010-01-01

In many metropolitan areas, traffic is the main source of air pollution. The high concentrations of pollutants in streets have the potential to affect human health. Therefore, estimation of air pollution at the street level is required for health impact assessment. This task has been carried out...... in many developed countries by a combination of air quality measurements and modeling. This study focuses on how to apply a dispersion model to cities in the developing world, where model input data and data from air quality monitoring stations are limited or of varying quality. This research uses...... the operational street pollution model (OSPM) developed by the National Environmental Research Institute in Denmark for a case study in Hanoi, the capital of Vietnam. OSPM predictions from five streets were evaluated against air pollution measurements of nitrogen oxides (NO), sulfur dioxide (SO2), carbon monoxide...

Evaluation of regional and local atmospheric dispersion models for the analysis of traffic-related air pollution in urban areas

Science.gov (United States)

Fallah-Shorshani, Masoud; Shekarrizfard, Maryam; Hatzopoulou, Marianne

2017-10-01

Dispersion of road transport emissions in urban metropolitan areas is typically simulated using Gaussian models that ignore the turbulence and drag induced by buildings, which are especially relevant for areas with dense downtown cores. To consider the effect of buildings, street canyon models are used but often at the level of single urban corridors and small road networks. In this paper, we compare and validate two dispersion models with widely varying algorithms, across a modelling domain consisting of the City of Montreal, Canada accounting for emissions of more 40,000 roads. The first dispersion model is based on flow decomposition into the urban canopy sub-flow as well as overlying airflow. It takes into account the specific height and geometry of buildings along each road. The second model is a Gaussian puff dispersion model, which handles complex terrain and incorporates three-dimensional meteorology, but accounts for buildings only through variations in the initial vertical mixing coefficient. Validation against surface observations indicated that both models under-predicted measured concentrations. Average weekly exposure surfaces derived from both models were found to be reasonably correlated (r = 0.8) although the Gaussian dispersion model tended to underestimate concentrations around the roadways compared to the street canyon model. In addition, both models were used to estimate exposures of a representative sample of the Montreal population composed of 1319 individuals. Large differences were noted whereby exposures derived from the Gaussian puff model were significantly lower than exposures derived from the street canyon model, an expected result considering the concentration of population around roadways. These differences have large implications for the analyses of health effects associated with NO2 exposure.

Air Pollution and Insulin Resistance: Do All Roads Lead to Rome?

Science.gov (United States)

The World Health Organization estimates that worldwide in 2012, nearly 7 million deaths occurred prematurely due to air pollution (1). In addition to respiratory and cardiovascular diseases, air pollution exposure is also linked to increased incidence of diabetes (2). Notably, th...

Road pricing policy implementation

NARCIS (Netherlands)

Vonk Noordegraaf, D.M.

2016-01-01

Urban areas suffer from the negative externalities of road transport like congested road networks, air pollution and road traffic accidents. A measure to reduce these negative externalities is road pricing, meaning policies that impose direct charges on road use (Jones and Hervik, 1992). Since the

Stormwater Pollution Prevention Plan TA-60 Roads and Grounds Facility and Associated Sigma Mesa Staging Area

Energy Technology Data Exchange (ETDEWEB)

Sandoval, Leonard Frank [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

2017-02-01

This Stormwater Pollution Prevention Plan (SWPPP) is applicable to operations at the Technical Area -60 (TA-60) Roads and Grounds Facility and Associated Sigma Mesa Staging Area off Eniwetok Drive, in Los Alamos County, New Mexico.

Willingness to pay to avoid health risks from road-traffic-related air pollution and noise across five countries.

Science.gov (United States)

Istamto, Tifanny; Houthuijs, Danny; Lebret, Erik

2014-11-01

We conducted a multi-country study to estimate the perceived economic values of traffic-related air pollution and noise health risks within the framework of a large European project. We used contingent valuation as a method to assess the willingness-to-pay (WTP) for both types of pollutants simultaneously. We asked respondents how much they would be willing to pay annually to avoid certain health risks from specific pollutants. Three sets of vignettes with different levels of information were provided prior to the WTP questions. These vignettes described qualitative general health risks, a quantitative single health risk related to a pollutant, and a quantitative scenario of combined health risks related to a pollutant. The mean WTP estimates to avoid road-traffic air pollution effects for the three vignettes were: €130 per person per year (pp/y) for general health risks, €80 pp/y for a half year shorter in life expectancy, and €330 pp/y to a 50% decrease in road-traffic air pollution. Their medians were €40 pp/y, €10 pp/y and €50 pp/y, respectively. The mean WTP estimates to avoid road-traffic noise effects for the three vignettes were: €90 pp/y for general health risks, €100 pp/y for a 13% increase in severe annoyance, and €320 pp/y for a combined-risk scenario related to an increase of a noise level from 50 dB to 65 dB. Their medians were €20 pp/y, €20 pp/y and €50 pp/y, respectively. Risk perceptions and attitudes as well as environmental and pollutant concerns significantly affected WTP estimates. The observed differences in crude WTP estimates between countries changed considerably when perception-related variables were included in the WTP regression models. For this reason, great care should be taken when performing benefit transfer from studies in one country to another. Copyright © 2014 The Authors. Published by Elsevier B.V. All rights reserved.

Recommendations for Constructing Roadside Vegetation Barriers to Improve Near-Road Air Quality

Science.gov (United States)

The EPA report, Recommendations for Constructing Roadside Vegetation Barriers to Improve Near-Road Air Quality, summarizes the research findings on the best practices for building roadside vegetative barriers to improve air quality. This fact sheet describ

Effective mitigation efforts to reduce road dust near industrial sites: assessment by mobile pollution surveys.

Science.gov (United States)

DeLuca, Patrick F; Corr, Denis; Wallace, Julie; Kanaroglou, Pavlos

2012-05-15

Assessment of spatial variation of fugitive dust sources, particularly road dust track-out from industrial sites and its subsequent re-suspension is difficult with fixed air quality monitoring stations given their sparse distribution and the highly localized nature of road dust. Mobile monitoring was employed to measure levels of road dust in the industrial area of the City of Hamilton, Ontario, Canada. Results of this monitoring were used in a Fugitive Dust Control workshop held for local stakeholders, where fugitive dust control solutions were presented. After the workshop, the City of Hamilton and cooperative industrial groups executed enhanced street cleaning and individual industries and facilities performed on-site control activities. Post-workshop mobile air monitoring was performed for comparison to the initial values to determine effectiveness of these approaches. A regression model testing the difference pre- and post-workshop yielded a statistically significant difference in PM(10) measurements demonstrating improvement. The average value of PM(10) prior to the workshop was 114 μg/m(3). Post-workshop the average value dropped to 73 μg/m(3). Copyright © 2012 Elsevier Ltd. All rights reserved.

Pollutant dispersion studies - An update on the problems in Indian coastal waters

Digital Repository Service at National Institute of Oceanography (India)

Swamy, G.N.

Pollutant dispersion problems along the Indian coastal waters are characterisEd. by site-specificity, as a result of seasonal and physiographic variabilities. Presence of large rivers, estuaries and backwaters add to the problems of waste disposal...

Long-term air pollution exposure and living close to busy roads are associated with COPD in women

Directory of Open Access Journals (Sweden)

Gehring Ulrike

2005-12-01

Full Text Available Abstract Background Lung function and exacerbations of chronic obstructive pulmonary disease (COPD have been associated with short-term exposure to air pollution. However, the effect of long-term exposure to particulate matter from industry and traffic on COPD as defined by lung function has not been evaluated so far. Our study was designed to investigate the influence of long-term exposure to air pollution on respiratory symptoms and pulmonary function in 55-year-old women. We especially focused on COPD as defined by GOLD criteria and additionally compared the effects of air pollution on respiratory symptoms by questionnaire data and by lung function measurements. Methods In consecutive cross sectional studies conducted between 1985–1994, we investigated 4757 women living in the Rhine-Ruhr Basin of Germany. NO2 and PM10 exposure was assessed by measurements done in an 8 km grid, and traffic exposure by distance from the residential address to the nearest major road using Geographic Information System data. Lung function was determined and COPD was defined by using the GOLD criteria. Chronic respiratory symptoms and possible confounders were defined by questionnaire data. Linear and logistic regressions, including random effects were used to account for confounding and clustering on city level. Results The prevalence of COPD (GOLD stages 1–4 was 4.5%. COPD and pulmonary function were strongest affected by PM10 and traffic related exposure. A 7 μg/m3 increase in five year means of PM10 (interquartile range was associated with a 5.1% (95% CI 2.5%–7.7% decrease in FEV1, a 3.7% (95% CI 1.8%–5.5% decrease in FVC and an odds ratio (OR of 1.33 (95% CI 1.03–1.72 for COPD. Women living less than 100 m from a busy road also had a significantly decreased lung function and COPD was 1.79 times more likely (95% CI 1.06–3.02 than for those living farther away. Chronic symptoms as based on questionnaire information showed effects in the same

Exposure to air pollution and noise from road traffic and risk of congenital anomalies in the Danish National Birth Cohort

DEFF Research Database (Denmark)

Pedersen, Marie; Garne, Ester; Hansen-Nord, Nete

2017-01-01

BACKGROUND: Ambient air pollution has been associated with certain congenital anomalies, but few studies rely on assessment of fine-scale variation in air quality and associations with noise from road traffic are unexplored. METHODS: Among 84,218 liveborn singletons (1997-2002) from the Danish...... associated with these subgroups of anomalies as well as with an increased OR for orofacial cleft anomalies (1.17, 0.94-1.47). Inverse associations for several both air pollution and noise were observed for atrial septal defects (0.85, 0.68-1.04 and 0.81, 0.65-0.99, respectively). CONCLUSIONS: Residential...... road traffic exposure to noise or air pollution during pregnancy did not seem to pose a risk for development of congenital anomalies....

Seasonal Changing Effect on Airflow and Pollutant Dispersion Characteristics in Urban Street Canyons

Directory of Open Access Journals (Sweden)

Jingliang Dong

2017-02-01

Full Text Available In this study, the effect of seasonal variation on air flow and pollutant dispersion characteristics was numerically investigated. A three-dimensional urban canopy model with unit aspect ratio (H/D = 1 was used to calculate surface temperature distribution in the street canyon. Four representative time events (1000 LST, 1300 LST, 1600 LST and 2000 LST during typical clear summer and winter days were selected to examine the air flow diurnal variation. The results revealed the seasonal variation significantly altered the street canyon microclimate. Compared with the street canyon surface temperature distribution in summer, the winter case showed a more evenly distributed surface temperature. In addition, the summer case showed greater daily temperature fluctuation than that of the winter case. Consequently, distinct pollutant dispersion patterns were observed between summer and winter scenarios, especially for the afternoon (1600 LST and night (2000 LST events. Among all studied time events, the pollutant removal performance of the morning (1000 LST and the night (2000 LST events were more sensitive to the seasonal variation. Lastly, limited natural ventilation performance was found during the summer morning and the winter night, which induced relatively high pollutant concentration along the pedestrian height level.

Grain size distribution of road-deposited sediment and its contribution to heavy metal pollution in urban runoff in Beijing, China.

Science.gov (United States)

Zhao, Hongtao; Li, Xuyong; Wang, Xiaomei; Tian, Di

2010-11-15

Pollutant washoff from road-deposited sediment (RDS) is an increasing problem associated with the rapid urbanization of China that results in urban non-point source pollution. Here, we analyzed the RDS grain size distribution and its potential impact on heavy metal pollution in urban runoff from impervious surfaces of urban villages, colleges and residences, and main traffic roads in the Haidian District, Beijing, China. RDS with smaller grain size had a higher metal concentration. Specifically, particles with the smallest grain size (runoff water accounted for greater than 70% of the metal mass in the total suspended solids (TSS). The heavy metal content in the TSS was 2.21-6.52% of that in the RDS. These findings will facilitate our understanding of the importance of RDS grain size distribution in heavy metal pollution caused by urban storm runoff. Copyright © 2010 Elsevier B.V. All rights reserved.

Air pollution abatement performances of green infrastructure in open road and built-up street canyon environments - A review

Science.gov (United States)

Abhijith, K. V.; Kumar, Prashant; Gallagher, John; McNabola, Aonghus; Baldauf, Richard; Pilla, Francesco; Broderick, Brian; Di Sabatino, Silvana; Pulvirenti, Beatrice

2017-08-01

Intensifying the proportion of urban green infrastructure has been considered as one of the remedies for air pollution levels in cities, yet the impact of numerous vegetation types deployed in different built environments has to be fully synthesised and quantified. This review examined published literature on neighbourhood air quality modifications by green interventions. Studies were evaluated that discussed personal exposure to local sources of air pollution under the presence of vegetation in open road and built-up street canyon environments. Further, we critically evaluated the available literature to provide a better understanding of the interactions between vegetation and surrounding built-up environments and ascertain means of reducing local air pollution exposure using green infrastructure. The net effects of vegetation in each built-up environment are also summarised and possible recommendations for the future design of green infrastructure are proposed. In a street canyon environment, high-level vegetation canopies (trees) led to a deterioration in air quality, while low-level green infrastructure (hedges) improved air quality conditions. For open road conditions, wide, low porosity and tall vegetation leads to downwind pollutant reductions while gaps and high porosity vegetation could lead to no improvement or even deteriorated air quality. The review considers that generic recommendations can be provided for vegetation barriers in open road conditions. Green walls and roofs on building envelopes can also be used as effective air pollution abatement measures. The critical evaluation of the fundamental concepts and the amalgamation of key technical features of past studies by this review could assist urban planners to design and implement green infrastructures in the built environment.

Use of a mobile laboratory to evaluate changes in on-road air pollutants during the Beijing 2008 Summer Olympics

Directory of Open Access Journals (Sweden)

Y. Li

2009-11-01

Full Text Available China implemented systematic air pollution control measures during the 2008 Beijing Summer Olympics and Paralympics to improve air quality. This study used a versatile mobile laboratory to conduct in situ monitoring of on-road air pollutants along Beijing's Fourth Ring Road on 31 selected days before, during, and after the Olympics air pollution control period. A suite of instruments with response times of less than 30 s was used to measure temporal and spatial variations in traffic-related air pollutants, including NO_x, CO, PM_1.0 surface area (S(PM₁, black carbon (BC, and benzene, toluene, the sum of ethylbenzene, and m-, p-, and o-xylene (BTEX. During the Olympics (8–23 August, 2008, on-road air pollutant concentrations decreased significantly, by up to 54% for CO, 41% for NO_x, 70% for SO₂, 66% for BTEX, 12% for BC, and 18% for S_PM1, compared with the pre-control period (before 20 July. Concentrations increased again after the control period ended (after 20 September, with average increases of 33% for CO, 42% for NO_x, 60% for SO₂, 40% for BTEX, 26% for BC, and 37% for S(PM₁, relative to the control period. Variations in pollutants concentrations were correlated with changes in traffic speed and the number and types of vehicles on the road. Throughout the measurement periods, the concentrations of NO_x, CO, and BTEX varied markedly with the numbers of light- and medium-duty vehicles (LDVs and MDVs, respectively on the road. Only after 8 August was a noticeable relationship found between BC and S(PM₁ and the number of heavy-duty vehicles (HDVs. Additionally, BC and S(PM₁ showed a strong correlation with SO₂ before the Olympics, indicating possible industrial sources from local emissions as well as regional transport activities in the Beijing area. Such factors were

Modeling pollutant dispersion within a tornadic thunderstorm

Energy Technology Data Exchange (ETDEWEB)

Pepper, D W

1982-01-01

A three-dimensional numerical model has been developed to calculate ground-level air concentration and deposition of particles entrained in a tornadic thunderstorm. The rotational characteristics of the tornadic storm are within the larger mesoscale flow of the storm system and transported with the vortex. Turbulence exchange coefficients are based on empirical values. The quasi-Lagrangian method of moments is used to model the transport of concentration within a grid cell volume. Results indicate that updrafts and downdrafts, coupled with scavenging of particles by precipitation, account for most of the material being deposited closer to the site than anticipated. Approximately 5% of the pollutant is dispersed into the stratosphere.

Factors influencing the spatial extent of mobile source air pollution impacts: a meta-analysis

Directory of Open Access Journals (Sweden)

Levy Jonathan I

2007-05-01

Full Text Available Abstract Background There has been growing interest among exposure assessors, epidemiologists, and policymakers in the concept of "hot spots", or more broadly, the "spatial extent" of impacts from traffic-related air pollutants. This review attempts to quantitatively synthesize findings about the spatial extent under various circumstances. Methods We include both the peer-reviewed literature and government reports, and focus on four significant air pollutants: carbon monoxide, benzene, nitrogen oxides, and particulate matter (including both ultrafine particle counts and fine particle mass. From the identified studies, we extracted information about significant factors that would be hypothesized to influence the spatial extent within the study, such as the study type (e.g., monitoring, air dispersion modeling, GIS-based epidemiological studies, focus on concentrations or health risks, pollutant under study, background concentration, emission rate, and meteorological factors, as well as the study's implicit or explicit definition of spatial extent. We supplement this meta-analysis with results from some illustrative atmospheric dispersion modeling. Results We found that pollutant characteristics and background concentrations best explained variability in previously published spatial extent estimates, with a modifying influence of local meteorology, once some extreme values based on health risk estimates were removed from the analysis. As hypothesized, inert pollutants with high background concentrations had the largest spatial extent (often demonstrating no significant gradient, and pollutants formed in near-source chemical reactions (e.g., nitrogen dioxide had a larger spatial extent than pollutants depleted in near-source chemical reactions or removed through coagulation processes (e.g., nitrogen oxide and ultrafine particles. Our illustrative dispersion model illustrated the complex interplay of spatial extent definitions, emission rates

Wind tunnel simulation of air pollution dispersion in a street canyon.

Science.gov (United States)

Civis, Svatopluk; Strizík, Michal; Janour, Zbynek; Holpuch, Jan; Zelinger, Zdenek

2002-01-01

Physical simulation was used to study pollution dispersion in a street canyon. The street canyon model was designed to study the effect of measuring flow and concentration fields. A method of C02-laser photoacoustic spectrometry was applied for detection of trace concentration of gas pollution. The advantage of this method is its high sensitivity and broad dynamic range, permitting monitoring of concentrations from trace to saturation values. Application of this method enabled us to propose a simple model based on line permeation pollutant source, developed on the principle of concentration standards, to ensure high precision and homogeneity of the concentration flow. Spatial measurement of the concentration distribution inside the street canyon was performed on the model with reference velocity of 1.5 m/s.

Validation of a two-dimensional pollutant dispersion model in an isolated street canyon

Energy Technology Data Exchange (ETDEWEB)

Chan, T.L.; Dong, G.; Leung, C.W.; Cheung, C.S. [The Hong Kong Polytechnic University, Kowloon (Hong Kong). Research Centre for Combustion and Pollution Control, Department of Mechanical Engineering; Hung, W.T. [The Hong Kong Polytechnic University, Kowloon (Hong Kong). Department of Civil and Structural Engineering

2002-07-01

A two-dimensional numerical model based on Reynolds-averaged Navier-Stokes equations coupled with a series of standard, Renormalization Group (RNG) and realizable k-{epsilon} turbulence models was developed to simulate the fluid-flow development and pollutant dispersion within an isolated street canyon using the FLUENT code. In the present study, the validation of the numerical model was evaluated using an extensive experimental database obtained from the atmospheric boundary layer wind tunnel at the Meteorological Institute of Hamburg University, Germany (J. Wind Eng. Ind. Aerodyn. 62 (1996) 37). Among the studied turbulence models, the RNG k-{epsilon} turbulence model was found to be the most optimum turbulence model coupled with the two-dimensional street canyon model developed in the present study. Both the calculated and measured dimensionless pollutant concentrations have been shown to be less dependent on the variation of wind speed and source strength conditions for the studied street canyon aspect ratio of the B/H=1 case. However, the street canyon configuration has significant influence on the pollutant dispersion. The wider street and lower height of the buildings are favorable to pollutant dilution within the street canyon. The fluid-flow development has demonstrated that the rotative vortex or vortices generated within the urban street canyon can transport the pollutants from a line source to the wall surfaces of the buildings. (author)

Predicting risk of trace element pollution from municipal roads using site-specific soil samples and remotely sensed data.

Science.gov (United States)

Reeves, Mari Kathryn; Perdue, Margaret; Munk, Lee Ann; Hagedorn, Birgit

2018-07-15

Studies of environmental processes exhibit spatial variation within data sets. The ability to derive predictions of risk from field data is a critical path forward in understanding the data and applying the information to land and resource management. Thanks to recent advances in predictive modeling, open source software, and computing, the power to do this is within grasp. This article provides an example of how we predicted relative trace element pollution risk from roads across a region by combining site specific trace element data in soils with regional land cover and planning information in a predictive model framework. In the Kenai Peninsula of Alaska, we sampled 36 sites (191 soil samples) adjacent to roads for trace elements. We then combined this site specific data with freely-available land cover and urban planning data to derive a predictive model of landscape scale environmental risk. We used six different model algorithms to analyze the dataset, comparing these in terms of their predictive abilities and the variables identified as important. Based on comparable predictive abilities (mean R 2 from 30 to 35% and mean root mean square error from 65 to 68%), we averaged all six model outputs to predict relative levels of trace element deposition in soils-given the road surface, traffic volume, sample distance from the road, land cover category, and impervious surface percentage. Mapped predictions of environmental risk from toxic trace element pollution can show land managers and transportation planners where to prioritize road renewal or maintenance by each road segment's relative environmental and human health risk. Published by Elsevier B.V.

Glass half-full: On-road glance metrics differentiate crashes from near-crashes in the 100-Car data.

Science.gov (United States)

Seppelt, Bobbie D; Seaman, Sean; Lee, Joonbum; Angell, Linda S; Mehler, Bruce; Reimer, Bryan

2017-10-01

Much of the driver distraction and inattention work to date has focused on concerns over drivers removing their eyes from the forward roadway to perform non-driving-related tasks, and its demonstrable link to safety consequences when these glances are timed at inopportune moments. This extensive literature has established, through the analyses of glance from naturalistic datasets, a clear relationship between eyes-off-road, lead vehicle closing kinematics, and near-crash/crash involvement. This paper looks at the role of driver expectation in influencing drivers' decisions about when and for how long to remove their eyes from the forward roadway in an analysis that consider the combined role of on- and off-road glances. Using glance data collected in the 100-Car Naturalistic Driving Study (NDS), near-crashes were examined separately from crashes to examine how momentary differences in glance allocation over the 25-s prior to a precipitating event can differentiate between these two distinct outcomes. Individual glance metrics of mean single glance duration (MSGD), total glance time (TGT), and glance count for off-road and on-road glance locations were analyzed. Output from the AttenD algorithm (Kircher and Ahlström, 2009) was also analyzed as a hybrid measure; in threading together on- and off-road glances over time, its output produces a pattern of glance behavior meaningful for examining attentional effects. Individual glance metrics calculated at the epoch-level and binned by 10-s units of time across the available epoch lengths revealed that drivers in near-crashes have significantly longer on-road glances, and look less frequently between on- and off- road locations in the moments preceding a precipitating event as compared to crashes. During on-road glances, drivers in near-crashes were found to more frequently sample peripheral regions of the roadway than drivers in crashes. Output from the AttenD algorithm affirmed the cumulative net benefit of longer on-road

Study of line source characteristics for 2-D physical modelling of pollutant dispersion in street canyons

Energy Technology Data Exchange (ETDEWEB)

Meroney, Robert N. [Fluid Mechanics and Wind Engineering Program, Civil Engineering Department, Colorado State University Fort Collins, CO (United States); Pavageau, Michel; Rafailidis, Stilianos; Schatzmann, Michael [Meteorologisches Institut, Universitaet Hamburg, Hamburg (Germany)

1996-08-01

The University of Hamburg initiated a wind tunnel study of car exhaust dispersion from street canyons in an urban environment to investigate how pollution dispersion is affected by street geometry. Particular emphasis at the beginning of this work was put on the design of a line source to represent traffic exhaust. Pollution dispersion was studied in two dimensions (i.e., infinite-length streets were assumed). The case of an isolated street canyon in open country was examined first. The same street canyon geometry was subsequently studied in an urban environment, i.e., with additional canyons of similar geometry upstream and downstream of the test street. The dynamic and dispersion characteristics of the flow in the two cases were quite different. In the canyon amidst open country we observed better canyon ventilation than in the urban roughness case

Congestion, air pollution, and road safety in urban areas

Energy Technology Data Exchange (ETDEWEB)

Shefer, Daniel [Department of Urban and Regional Economics and Transport, Technion-Israel Institute of Technology, Haifa (Israel)

1993-06-01

The continuous rapid growth in Vehicle Miles Travelled (VMT), coupled with the rapid increase in traffic congestion on highways of virtually every large urban area, explain a major portion of the observed deterioration of urban air quality. To halt this deterioration process and to secure safe and healthy environments and improve the quality of life in our cities, it is paramount to initiate and implement programs which jointly treat traffic congestion, air quality, and road safety. A host of market-based strategies, driven by price mechanisms, have been proposed as the best and most efficient way to decrease traffic congestion and to reduce vehicle emission. Congestion pricing, emission fees, reducing emissions of high polluting vehicles, and introducing more efficient vehicle and/or fuel technologies are not mutually exclusive strategies and therefore they can, and perhaps should, be employed jointly within an overall strategy. In view of the conflicting objectives which may exist between improving urban air quality and reducing road fatalities and traffic congestion, it is of great importance to thoroughly investigate these functional relationships. The results of such studies will help decision makers identify the `socially optimal level of congestion` which will yield the highest net social benefit. 2 figs., 43 refs.

Evaluation of the use of bioethanol fuelled buses based on ambient air pollution screening and on-road measurements

Energy Technology Data Exchange (ETDEWEB)

López-Aparicio, S., E-mail: sla@nilu.no; Hak, C.

2013-05-01

Mitigation measures to reduce greenhouse gas emissions may have adverse effects on urban air quality and human exposure to harmful pollutants. The use of bioethanol fuelled vehicles is increasing worldwide and may create new undesired pollution effects. Different measurement campaigns were performed in a pilot study to contribute to the understanding of the consequences associated with the use of bioethanol blended fuel (E95) on a series of pollutants. Ambient screening measurements of NO{sub 2}, O{sub 3}, acetic acid, formaldehyde and acetaldehyde were performed at different urban locations, exposed and not exposed to the circulation of bioethanol buses. In addition, volatile organic compounds were measured at the exhaust pipe of a bioethanol fuelled bus, both under idling conditions (carbonyls; DNPH cartridge) and under on-road driving conditions applying online monitoring (PTR-TOF). Higher ambient acetaldehyde values were measured at locations exposed to bioethanol fuelled buses than at locations not exposed, and very high acetaldehyde and acetic acid values were measured from the exhaust pipe during driving conditions (acetaldehyde > 150 ppm; acetic acid ≈ 20–30 ppm) and modelled at close distance to the bioethanol bus. Human exposure to high concentration of acetaldehyde is expected, and it may involve a significantly increased chance in developing cancer. The high concentration of acetic acid will involve odour annoyance and significant material degradation or corrosion. - Highlights: ► Acetaldehyde levels above 150 ppm were measured from the bioethanol bus. ► High acetic acid levels (20–30 ppm) were measured from the bioethanol bus. ► Demonstrated usefulness of PTR-MS to evaluate non-criteria pollutants ► High levels of acetaldehyde and acetic acid are estimated in the dispersion plume. ► Climate mitigation measures may have adverse impact on air quality.

Evaluation of the use of bioethanol fuelled buses based on ambient air pollution screening and on-road measurements

International Nuclear Information System (INIS)

López-Aparicio, S.; Hak, C.

2013-01-01

Mitigation measures to reduce greenhouse gas emissions may have adverse effects on urban air quality and human exposure to harmful pollutants. The use of bioethanol fuelled vehicles is increasing worldwide and may create new undesired pollution effects. Different measurement campaigns were performed in a pilot study to contribute to the understanding of the consequences associated with the use of bioethanol blended fuel (E95) on a series of pollutants. Ambient screening measurements of NO 2 , O 3 , acetic acid, formaldehyde and acetaldehyde were performed at different urban locations, exposed and not exposed to the circulation of bioethanol buses. In addition, volatile organic compounds were measured at the exhaust pipe of a bioethanol fuelled bus, both under idling conditions (carbonyls; DNPH cartridge) and under on-road driving conditions applying online monitoring (PTR-TOF). Higher ambient acetaldehyde values were measured at locations exposed to bioethanol fuelled buses than at locations not exposed, and very high acetaldehyde and acetic acid values were measured from the exhaust pipe during driving conditions (acetaldehyde > 150 ppm; acetic acid ≈ 20–30 ppm) and modelled at close distance to the bioethanol bus. Human exposure to high concentration of acetaldehyde is expected, and it may involve a significantly increased chance in developing cancer. The high concentration of acetic acid will involve odour annoyance and significant material degradation or corrosion. - Highlights: ► Acetaldehyde levels above 150 ppm were measured from the bioethanol bus. ► High acetic acid levels (20–30 ppm) were measured from the bioethanol bus. ► Demonstrated usefulness of PTR-MS to evaluate non-criteria pollutants ► High levels of acetaldehyde and acetic acid are estimated in the dispersion plume. ► Climate mitigation measures may have adverse impact on air quality

Inroads into Equestrian Safety: Rider-Reported Factors Contributing to Horse-Related Accidents and Near Misses on Australian Roads

Directory of Open Access Journals (Sweden)

Kirrilly Thompson

2015-07-01

Full Text Available Horse riding and horse-related interactions are inherently dangerous. When they occur on public roads, the risk profile of equestrian activities is complicated by interactions with other road users. Research has identified speed, proximity, visibility, conspicuity and mutual misunderstanding as factors contributing to accidents and near misses. However, little is known about their significance or incidence in Australia. To explore road safety issues amongst Australian equestrians, we conducted an online survey. More than half of all riders (52% reported having experienced at least one accident or near miss in the 12 months prior to the survey. Whilst our findings confirm the factors identified overseas, we also identified issues around rider misunderstanding of road rules and driver misunderstanding of rider hand signals. Of particular concern, we also found reports of potentially dangerous rider-directed road rage. We identify several areas for potential safety intervention including (1 identifying equestrians as vulnerable road users and horses as sentient decision-making vehicles (2 harmonising laws regarding passing horses, (3 mandating personal protective equipment, (4 improving road signage, (5 comprehensive data collection, (6 developing mutual understanding amongst road-users, (7 safer road design and alternative riding spaces; and (8 increasing investment in horse-related safety initiatives.

Inroads into Equestrian Safety: Rider-Reported Factors Contributing to Horse-Related Accidents and Near Misses on Australian Roads.

Science.gov (United States)

Thompson, Kirrilly; Matthews, Chelsea

2015-07-22

Horse riding and horse-related interactions are inherently dangerous. When they occur on public roads, the risk profile of equestrian activities is complicated by interactions with other road users. Research has identified speed, proximity, visibility, conspicuity and mutual misunderstanding as factors contributing to accidents and near misses. However, little is known about their significance or incidence in Australia. To explore road safety issues amongst Australian equestrians, we conducted an online survey. More than half of all riders (52%) reported having experienced at least one accident or near miss in the 12 months prior to the survey. Whilst our findings confirm the factors identified overseas, we also identified issues around rider misunderstanding of road rules and driver misunderstanding of rider hand signals. Of particular concern, we also found reports of potentially dangerous rider-directed road rage. We identify several areas for potential safety intervention including (1) identifying equestrians as vulnerable road users and horses as sentient decision-making vehicles (2) harmonising laws regarding passing horses, (3) mandating personal protective equipment, (4) improving road signage, (5) comprehensive data collection, (6) developing mutual understanding amongst road-users, (7) safer road design and alternative riding spaces; and (8) increasing investment in horse-related safety initiatives.

Mobile system for on-road measurements of air pollutants

Science.gov (United States)

Katulski, Ryszard J.; Namieśnik, Jacek; Sadowski, Jarosław; Stefański, Jacek; Szymańska, Krystyna; Wardencki, Waldemar

2010-04-01

The paper presents a prototype of a mobile monitoring system for measuring the levels of the main traffic air pollutants (C6H6, NO2, NOx, CO, and CO2,) in cities. The novelty of the proposed system lies in the fact that it can be utilized to monitor emissions from urban traffic along roads and areas where traditional monitoring stations cannot be placed. In the proposed system, the monitoring device can be mounted on any moving vehicle (such as a car, bus, or truck) rather than be attached to a dedicated van, as most systems of this kind found in literature are. Analyzers used in this system are small portable structures that contain an electronic instrument to measure, record, and transmit relevant data on concentrations of the pollutants to a website. The model outcome for carbon monoxide obtained in functional tests in real conditions is also presented here. Data on temporal changes of carbon monoxide concentration are compared against meteorological parameters and speed of the vehicle. Spatial interpolation techniques are applied to obtain a nonplanar visualization of carbon monoxide and benzene concentrations in the main arteries of a city.

Air pollution and climate change co-benefit opportunities in the road transportation sector in Durban, South Africa

CSIR Research Space (South Africa)

Thambiran T, Diab RD

2011-01-01

Full Text Available The contribution of the road transportation sector to emissions of air pollutants and greenhouse gases is a growing concern in developing countries. Emission control measures implemented within this sector can have varying counteracting influences...

Dispersion modeling by kinematic simulation: Cloud dispersion model

International Nuclear Information System (INIS)

Fung, J C H; Perkins, R J

2008-01-01

A new technique has been developed to compute mean and fluctuating concentrations in complex turbulent flows (tidal current near a coast and deep ocean). An initial distribution of material is discretized into any small clouds which are advected by a combination of the mean flow and large scale turbulence. The turbulence can be simulated either by kinematic simulation (KS) or direct numerical simulation. The clouds also diffuse relative to their centroids; the statistics for this are obtained from a separate calculation of the growth of individual clouds in small scale turbulence, generated by KS. The ensemble of discrete clouds is periodically re-discretized, to limit the size of the small clouds and prevent overlapping. The model is illustrated with simulations of dispersion in uniform flow, and the results are compared with analytic, steady state solutions. The aim of this study is to understand how pollutants disperses in a turbulent flow through a numerical simulation of fluid particle motion in a random flow field generated by Fourier modes. Although this homogeneous turbulent is rather a 'simple' flow, it represents a building block toward understanding pollutant dispersion in more complex flow. The results presented here are preliminary in nature, but we expect that similar qualitative results should be observed in a genuine turbulent flow.

Identifying the contribution of different urban highway air pollution sources

International Nuclear Information System (INIS)

Peace, H.; Owen, B.; Raper, D.W.

2004-01-01

This paper describes the methodology and results, and draws conclusions from a large-scale source apportionment study undertaken in a large urban conurbation in the northwest of England. Annual average oxides of nitrogen (NOx) emission and ambient air pollution contributions have been estimated for road traffic sources. Ground level air pollution concentrations were estimated over a 1552-km 2 area with a resolution of up to 20 m, using emissions estimates and the second generation ADMS-Urban Gaussian dispersion model. Road traffic emissions were split into car and motorcycles; heavy and light goods vehicles; and buses to represent domestic users; commercial users and bus companies. Car related emissions were split further in to journey lengths under 3 km; journeys between 3 and 8 km; and journeys over 8 km to represent journeys which could be either walked or cycled; journeys for which a bus can easily be used and other journeys. These source sections were chosen so that the relevant authorities could target key groups in terms of reducing air pollution. The results confirm that the areas most likely to exceed air quality objectives are typically close to main arterial routes and close to urban centres and that the major culprits of road traffic related air pollution are goods vehicles and car journeys over 8 km. The paper also discusses the implications of the results and suggests how these can be used in the assessment of actions to reduce air pollution concentrations

Identifying the contribution of different urban highway air pollution sources.

Science.gov (United States)

Peace, H; Owen, B; Raper, D W

2004-12-01

This paper describes the methodology and results, and draws conclusions from a large-scale source apportionment study undertaken in a large urban conurbation in the northwest of England. Annual average oxides of nitrogen (NOx) emission and ambient air pollution contributions have been estimated for road traffic sources. Ground level air pollution concentrations were estimated over a 1552-km(2) area with a resolution of up to 20 m, using emissions estimates and the second generation ADMS-Urban Gaussian dispersion model. Road traffic emissions were split into car and motorcycles; heavy and light goods vehicles; and buses to represent domestic users; commercial users and bus companies. Car related emissions were split further in to journey lengths under 3 km; journeys between 3 and 8 km; and journeys over 8 km to represent journeys which could be either walked or cycled; journeys for which a bus can easily be used and other journeys. These source sections were chosen so that the relevant authorities could target key groups in terms of reducing air pollution. The results confirm that the areas most likely to exceed air quality objectives are typically close to main arterial routes and close to urban centres and that the major culprits of road traffic related air pollution are goods vehicles and car journeys over 8 km. The paper also discusses the implications of the results and suggests how these can be used in the assessment of actions to reduce air pollution concentrations.

Gestational diabetes mellitus and exposure to ambient air pollution and road traffic noise

DEFF Research Database (Denmark)

Pedersen, Marie; Olsen, Sjurdur F; Halldorsson, Thorhallur I

2017-01-01

pollution and road traffic noise on GDM in a prospective cohort. Methods: We identified GDM cases from self-reports and hospital records, using two different criteria, among 72,745 singleton pregnancies (1997–2002) from the Danish National Birth Cohort. We modeled nitrogen dioxide (NO2) and noise from road...... traffic (Lden) exposure at all pregnancy addresses. Results: According to the two diagnostic criteria: the Danish clinical guidelines, which was our main outcome, and the WHO standard during recruitment period, a total of 565 and 210 women, respectively, had GDM. For both exposures no risk was evident......: No risk was evident for the common Danish criterion of GDM. NO2 was associated with higher risk for GDM according to the WHO criterion, which might be due to selection bias....

Survey of gaseous air pollutants at selected UK sites: XXI. Data digest for Cromwell Road, London, 1984

Energy Technology Data Exchange (ETDEWEB)

Broughton, G.F.J.; Bower, J.; Drury, V.J.; Lilley, K.; Powell, K.

1987-01-01

Ambient air-quality measurements of four gaseous pollutants plus black smoke and particulate lead continued during 1984 at the Cromwell Road kerbside site sponsored by the Department of the Environment. These data are presented here in the form of frequency distributions, averages, and other parameters for winter, summer, annual and monthly periods. Time-series graphs of pollutant concentrations for 1984 and of the historical data base between March 1973 and December 1984 are also included.

Mechanical resuspension of 239Pu from unpaved roads

International Nuclear Information System (INIS)

Hodgin, C.R.

1982-01-01

The impacts of resuspended plutonium from two unpaved roads at the Rocky Flats Plant on nearby air samplers were investigated. Because the sources were complex fugitive dust emitters and because of the small source-receptor distances, traditional dispersion modeling techniques could not be employed. Thus two specialized techniques, one for fugitive dust emissions and one for near distance dispersion, were developed and used to calculate atmospheric dust concentrations at the subject air samplers. Atmospheric 239 Pu impacts were then determined from measurements of plutonium concentrations in the resuspendible dust on the road surfaces. As a final step in the process the calculated plutonium impacts were compared to the 1980 annual average 239 Pu concentration at four samplers. The impact calculated for the Gunnery Range Road represented 2.1 percent of the observed annual concentration, with a 95 percent confidence interval of 1.1 to 7.9 percent. The Southeast Perimeter Road produced a more substantial effect with a point estimate of 3.8 percent. The 95 percent confidence interval for this source was 2.0 to 9.1 percent. The combined impact of the two roads on the subject samplers was 5.9 percent of the observed plutonium concentration, with a 95 percent confidence interval of 3.2 to 17.0 percent. Thus it was shown that fugitive plutonium emissions from the Gunnery Range Road and Southeast Perimeter Road are not substantial contributors to the plutonium concentrations observed at the subject samplers. Even an increase in dust control efficiency to 90 percent (as with paving) would result in only a four percent decrease in the overall atmosperic plutonium concentration at the site

Measurements and predictors of on-road ultrafine particle concentrations and associated pollutants in Los Angeles

Energy Technology Data Exchange (ETDEWEB)

Fruin, S. [California Air Resources Board, Sacramento (United States); University of Southern California, Los Angeles (United States). Keck School of Medicine, Department of Preventive Medicine; Westerdahl, D.; Sax, T. [California Air Resources Board, Sacramento (United States); Sioutas, C. [University of Southern California, Los Angeles (United States). Civil and Environmental Engineering; Fine, P.M. [University of Southern California, Los Angeles (United States). Civil and Environmental Engineering; South Coast Air Quality Management District, Diamond Bar, CA (United States)

2008-01-15

Motor vehicles are the dominant source of oxides of nitrogen (NO{sub x}), particulate matter(PM), and certain air toxics (e.g., benzene, 1,3-butadiene) in urban areas. On roadways, motor vehicle-related pollutant concentrations are typically many times higher than ambient concentrations. Due to high air exchange rates typical of moving vehicles, this makes time spent in vehicles on roadways a major source of exposure. This paper presents on-road measurements for Los Angeles freeways and arterial roads taken from a zero-emission electric vehicle outfitted with real-time instruments. The objective was to characterize air pollutant concentrations on roadways and identify the factors associated with the highest concentrations. Our analysis demonstrated that on freeways, concentrations of ultrafine particles (UFPs), black carbon, nitric oxide, and PM-bound polycyclic aromatic hydrocarbons (PM-PAH) are generated primarily by diesel-powered vehicles, despite the relatively low fraction ({approx}6%) of diesel-powered vehicles on Los Angeles freeways. However, UFP concentrations on arterial roads appeared to be driven primarily by proximity to gasoline-powered vehicles undergoing hard accelerations. Concentrations were roughly one-third of those on freeways. By using a multiple regression model for the freeway measurements, we were able to explain 60-70% of the variability in concentrations of UFP, black carbon, nitric oxide, and PM-PAH using measures of diesel truck density and hour of day (as an indicator of wind speed). Freeway concentrations of these pollutants were also well correlated wth readily available annual average daily truck counts, potentially allowing improved population exposure estimates for epidemiology studies. Based on these roadway measurements and average driving time, it appears that 33-45% of total UFP exposure for Los Angeles residents occurs due to time spent traveling in vehicles. (author)

Measurements and predictors of on-road ultrafine particle concentrations and associated pollutants in Los Angeles

International Nuclear Information System (INIS)

Fruin, S.; Sioutas, C.

2008-01-01

Motor vehicles are the dominant source of oxides of nitrogen (NO x ), particulate matter(PM), and certain air toxics (e.g., benzene, 1,3-butadiene) in urban areas. On roadways, motor vehicle-related pollutant concentrations are typically many times higher than ambient concentrations. Due to high air exchange rates typical of moving vehicles, this makes time spent in vehicles on roadways a major source of exposure. This paper presents on-road measurements for Los Angeles freeways and arterial roads taken from a zero-emission electric vehicle outfitted with real-time instruments. The objective was to characterize air pollutant concentrations on roadways and identify the factors associated with the highest concentrations. Our analysis demonstrated that on freeways, concentrations of ultrafine particles (UFPs), black carbon, nitric oxide, and PM-bound polycyclic aromatic hydrocarbons (PM-PAH) are generated primarily by diesel-powered vehicles, despite the relatively low fraction (∼6%) of diesel-powered vehicles on Los Angeles freeways. However, UFP concentrations on arterial roads appeared to be driven primarily by proximity to gasoline-powered vehicles undergoing hard accelerations. Concentrations were roughly one-third of those on freeways. By using a multiple regression model for the freeway measurements, we were able to explain 60-70% of the variability in concentrations of UFP, black carbon, nitric oxide, and PM-PAH using measures of diesel truck density and hour of day (as an indicator of wind speed). Freeway concentrations of these pollutants were also well correlated wth readily available annual average daily truck counts, potentially allowing improved population exposure estimates for epidemiology studies. Based on these roadway measurements and average driving time, it appears that 33-45% of total UFP exposure for Los Angeles residents occurs due to time spent traveling in vehicles. (author)

Measurements and predictors of on-road ultrafine particle concentrations and associated pollutants in Los Angeles

Science.gov (United States)

Fruin, S.; Westerdahl, D.; Sax, T.; Sioutas, C.; Fine, P. M.

Motor vehicles are the dominant source of oxides of nitrogen (NO x), particulate matter (PM), and certain air toxics (e.g., benzene, 1,3-butadiene) in urban areas. On roadways, motor vehicle-related pollutant concentrations are typically many times higher than ambient concentrations. Due to high air exchange rates typical of moving vehicles, this makes time spent in vehicles on roadways a major source of exposure. This paper presents on-road measurements for Los Angeles freeways and arterial roads taken from a zero-emission electric vehicle outfitted with real-time instruments. The objective was to characterize air pollutant concentrations on roadways and identify the factors associated with the highest concentrations. Our analysis demonstrated that on freeways, concentrations of ultrafine particles (UFPs), black carbon, nitric oxide, and PM-bound polycyclic aromatic hydrocarbons (PM-PAH) are generated primarily by diesel-powered vehicles, despite the relatively low fraction (˜6%) of diesel-powered vehicles on Los Angeles freeways. However, UFP concentrations on arterial roads appeared to be driven primarily by proximity to gasoline-powered vehicles undergoing hard accelerations. Concentrations were roughly one-third of those on freeways. By using a multiple regression model for the freeway measurements, we were able to explain 60-70% of the variability in concentrations of UFP, black carbon, nitric oxide, and PM-PAH using measures of diesel truck density and hour of day (as an indicator of wind speed). Freeway concentrations of these pollutants were also well correlated with readily available annual average daily truck counts, potentially allowing improved population exposure estimates for epidemiology studies. Based on these roadway measurements and average driving time, it appears that 33-45% of total UFP exposure for Los Angeles residents occurs due to time spent traveling in vehicles.

Gestational diabetes mellitus and exposure to ambient air pollution and road traffic noise: A cohort study.

Science.gov (United States)

Pedersen, Marie; Olsen, Sjurdur F; Halldorsson, Thorhallur I; Zhang, Cuilin; Hjortebjerg, Dorrit; Ketzel, Matthias; Grandström, Charlotta; Sørensen, Mette; Damm, Peter; Langhoff-Roos, Jens; Raaschou-Nielsen, Ole

2017-11-01

Road traffic is a main source of air pollution and noise. Both exposures have been associated with type 2 diabetes, but associations with gestational diabetes mellitus (GDM) have been studied less. We aimed to examine single and joint associations of exposure to air pollution and road traffic noise on GDM in a prospective cohort. We identified GDM cases from self-reports and hospital records, using two different criteria, among 72,745 singleton pregnancies (1997-2002) from the Danish National Birth Cohort. We modeled nitrogen dioxide (NO 2 ) and noise from road traffic (L den ) exposure at all pregnancy addresses. According to the two diagnostic criteria: the Danish clinical guidelines, which was our main outcome, and the WHO standard during recruitment period, a total of 565 and 210 women, respectively, had GDM. For both exposures no risk was evident for the common Danish criterion of GDM. A 10-μg/m 3 increase in NO 2 exposure during first trimester was, however, associated with an increased risk of WHO-GDM (adjusted odds ratio (OR)=1.24; 95% confidence interval (CI): 1.03, 1.49). The corresponding OR associated with a 10-dB higher road traffic noise level was 1.15 (0.94 to 1.18). In mutually adjusted models the OR for NO 2 remained similar 1.22 (0.98, 1.53) whereas that for road traffic noise decreased to 1.03 (0.80, 1.32). Significant associations were also observed for exposure averaged over the 2nd and 3rd trimesters and the full pregnancy. No risk was evident for the common Danish criterion of GDM. NO 2 was associated with higher risk for GDM according to the WHO criterion, which might be due to selection bias. Copyright © 2017 Elsevier Ltd. All rights reserved.

Impacts of traffic composition and street-canyon geometry on on-road air quality in a high-rise building area

Science.gov (United States)

Kwak, Kyung-Hwan; Kim, Kyung Hwan; Lee, Seung-Bok; Woo, Sung Ho; Bae, Gwi-Nam; Sunwoo, Young; Baik, Jong-Jin

2016-04-01

Mobile measurements using a mobile laboratory and numerical simulations using a computational fluid dynamics (CFD) model were conducted over different time periods of multiple days in a high-rise building area, Seoul, Republic of Korea. Mobile measurement can provide actual on-road emission levels of air pollutants from vehicles as well as validation dataset of a CFD model. On the other hand, CFD modeling is required for the process analysis of mobile measurement data and the quantitative estimation of determining factors in complex phenomena. The target area is characterized as a busy street canyon elongated along a major road with hourly traffic volumes of approximately 4000 vehicles during working hours on weekdays. Nitrogen oxides (NOx), black carbon (BC), particle-bound polycyclic aromatic hydrocarbons (pPAH), and particle number (PN) concentrations were measured during 39 round trips of mobile laboratory. The associations of the measured NOx, BC, pPAH, and PN concentrations with the traffic volumes of individual compositions are analyzed by calculating the correlation coefficients (R2) based on linear regressions. It is found that SUV, truck, van, and bus are heavy emitters responsible for the on-road air pollution in the street canyon. Among the measured pollutants, the largest R2 is shown for pPAH. The measured NOx, BC, pPAH, and PN concentrations are unevenly distributed in the street canyon. The measured concentrations around an intersection are higher than those in between intersections, particularly for NOx and pPAH. The CFD modeling for different dispersion scenarios reveals that the intersection has counterbalancing roles in determining the on-road concentrations. The emission process acts to increase the on-road concentrations due to accelerating and idling vehicles, whereas the dispersion process acts to decrease the on-road concentrations due to lateral ventilations along the crossing street. It is needed to control the number of heavy emitters and

Dispersion Models to Forecast Traffic-related Emissions in Urban Areas

Directory of Open Access Journals (Sweden)

Davide Scannapieco

2011-11-01

Full Text Available Down the centuries, a direct link had been developed between increase in mobility and increase in wealth. On the other hand, air emission of greenhouse gases (GHG due to vehicles equipped with internal combustion engines can be regarded as a negative pressure over the environment. In the coming decades, road transport is likely to remain a significant contributor to air pollution in cities. Many urban trips cover distances of less than 6 km. Since the effectiveness of catalytic converters in the initial minutes of engine operation is small, the average emission per distance driven is very high in urban areas. Also, poorly maintained vehicles that lack exhaust aftertreatment systems are responsible for a major part of pollutant emissions. Therefore in urban areas, where higher concentrations of vehicles can be easily found, air pollution represents a critical issue, being it related with both environment and human health protection: in truth, research in recent decades consistently indicates the adverse effects of outdoor air pollution on human health, and the evidence points to air pollution stemming from transport as an important contributor to these effects. Several institutions (EEA, USEPA, etc. focused their interest in dispersion models because of their potential effectiveness to forecast atmospheric pollution. Furthermore, air micropollutants such as Polycyclic Aromatic Compounds (PAH and Metallic Trace Elements (MTE are traffic-related and although very low concentrations their dispersion is a serious issue. However, dispersion models are usefully implemented to better manage this estimation problem. Nonetheless, policy makers and land managers have to deal with model selection, taking into account that several dispersion models are available, each one of them focused on specific goals (e.g., wind transport of pollutants, land morphology implementation, evaluation of micropollutants transport, etc.; a further aspect to be considered is

Pollutant Dispersion Modeling in Natural Streams Using the Transmission Line Matrix Method

Directory of Open Access Journals (Sweden)

Safia Meddah

2015-09-01

Full Text Available Numerical modeling has become an indispensable tool for solving various physical problems. In this context, we present a model of pollutant dispersion in natural streams for the far field case where dispersion is considered longitudinal and one-dimensional in the flow direction. The Transmission Line Matrix (TLM, which has earned a reputation as powerful and efficient numerical method, is used. The presented one-dimensional TLM model requires a minimum input data and provides a significant gain in computing time. To validate our model, the results are compared with observations and experimental data from the river Severn (UK. The results show a good agreement with experimental data. The model can be used to predict the spatiotemporal evolution of a pollutant in natural streams for effective and rapid decision-making in a case of emergency, such as accidental discharges in a stream with a dynamic similar to that of the river Severn (UK.

How the Guangzhou Government Can Curtail Air Pollution from Road Traffic in a Least Costly Manner

Energy Technology Data Exchange (ETDEWEB)

Zhao, Xu

1998-12-01

This thesis explores the relationship between the increased motorized traffic and air pollution in urban Guangzhou, the prosperous capital of the Guangdong Province in southern China that is located in the vicinity of Hong Kong and Macao. The emphasis is placed on PM 10 pollutants (particles of less than 10 microns in size). It reviews the current status of ambient air quality, the harmful effects of PM 10 emissions on human health and how to reduce the problem. It is estimated that 3300 premature deaths per year could be avoided if Guangzhou met the Class II of the Chinese National Ambient Air Quality Standard for PM 10, and the Guangzhou Government could save 10% of its GDP in 1994. A theoretical framework for reducing pollution problems is presented based on cost-effectiveness theory. There is also an overview of possible pollution reducing measures based on worldwide experience. The theoretical framework is applied to a case study of selected measures: (1) reduced sulfur content of diesel fuel, (2) creating bus lanes, (3) fuel taxation, (4) introduction of toll roads, (5) measures on the metro line. The bus lane measure is found to be the most cost-effective one, followed by the toll road and fuel taxation measures. The metro measure is the most expensive one. Finally, the report recommends to the Guangzhou Government what measures should have first priority according to cost-effectiveness. 23 refs., 14 figs., 21 tabs.

Use of porous asphalt on major roads in Johannesburg

CSIR Research Space (South Africa)

Horak, E

1994-10-01

Full Text Available Roads with high traffic volumes are synonymous with high road related noise levels. In Johannesburg road related noise pollution is recognised as a negative environmental impact. The Noise Pollution Unit of Johannesburg City Council regularly...

Numerical Study on Sensitivity of Pollutant Dispersion on Turbulent Schmidt Number in a Street Canyon

Science.gov (United States)

WANG, J.; Kim, J.

2014-12-01

In this study, sensitivity of pollutant dispersion on turbulent Schmidt number (Sct) was investigated in a street canyon using a computational fluid dynamics (CFD) model. For this, numerical simulations with systematically varied Sct were performed and the CFD model results were validated against a wind‒tunnel measurement data. The results showed that root mean square error (RMSE) was quite dependent on Sct and dispersion patterns of non‒reactive scalar pollutant with different Sct were quite different among the simulation results. The RMSE was lowest in the case of Sct = 0.35 and the apparent dispersion pattern was most similar to the wind‒tunnel data in the case of Sct = 0.35. Also, numerical simulations using spatially weighted Sct were additionally performed in order for the best reproduction of the wind‒tunnel data. Detailed method and procedure to find the best reproduction will be presented.

Long-term exposure to road traffic noise, ambient air pollution, and cardiovascular risk factors in the HUNT and lifelines cohorts.

Science.gov (United States)

Cai, Yutong; Hansell, Anna L; Blangiardo, Marta; Burton, Paul R; de Hoogh, Kees; Doiron, Dany; Fortier, Isabel; Gulliver, John; Hveem, Kristian; Mbatchou, Stéphane; Morley, David W; Stolk, Ronald P; Zijlema, Wilma L; Elliott, Paul; Hodgson, Susan

2017-08-01

Blood biochemistry may provide information on associations between road traffic noise, air pollution, and cardiovascular disease risk. We evaluated this in two large European cohorts (HUNT3, Lifelines). Road traffic noise exposure was modelled for 2009 using a simplified version of the Common Noise Assessment Methods in Europe (CNOSSOS-EU). Annual ambient air pollution (PM10, NO2) at residence was estimated for 2007 using a Land Use Regression model. The statistical platform DataSHIELD was used to pool data from 144 082 participants aged ≥20 years to enable individual-level analysis. Generalized linear models were fitted to assess cross-sectional associations between pollutants and high-sensitivity C-reactive protein (hsCRP), blood lipids and for (Lifelines only) fasting blood glucose, for samples taken during recruitment in 2006-2013. Pooling both cohorts, an inter-quartile range (IQR) higher day-time noise (5.1 dB(A)) was associated with 1.1% [95% confidence interval (95% CI: 0.02-2.2%)] higher hsCRP, 0.7% (95% CI: 0.3-1.1%) higher triglycerides, and 0.5% (95% CI: 0.3-0.7%) higher high-density lipoprotein (HDL); only the association with HDL was robust to adjustment for air pollution. An IQR higher PM10 (2.0 µg/m3) or NO2 (7.4 µg/m3) was associated with higher triglycerides (1.9%, 95% CI: 1.5-2.4% and 2.2%, 95% CI: 1.6-2.7%), independent of adjustment for noise. Additionally for NO2, a significant association with hsCRP (1.9%, 95% CI: 0.5-3.3%) was seen. In Lifelines, an IQR higher noise (4.2 dB(A)) and PM10 (2.4 µg/m3) was associated with 0.2% (95% CI: 0.1-0.3%) and 0.6% (95% CI: 0.4-0.7%) higher fasting glucose respectively, with both remaining robust to adjustment for air/noise pollution. Long-term exposures to road traffic noise and ambient air pollution were associated with blood biochemistry, providing a possible link between road traffic noise/air pollution and cardio-metabolic disease risk. Published on behalf of the European Society of

On street observations of particulate matter movement and dispersion due to traffic on an urban road

Science.gov (United States)

Patra, Aditya; Colvile, Roy; Arnold, Samantha; Bowen, Emma; Shallcross, Dudley; Martin, Damien; Price, Catheryn; Tate, James; ApSimon, Helen; Robins, Alan

Empirical models for particulate matter emissions from paved road surfaces have been criticised for their lack of realism and accuracy. To support the development of a less empirical model, a study was conducted in a busy street at the DAPPLE site in Central London to understand the processes and to identify important parameters that influence emission from paved roads. Ordinary road gritting salt was applied to the road and the particulate matter entering the air at near-road surface level was monitored using optical particle counters. The grit acted as a tracer. The grit moved rapidly along the road in the direction of traffic flow. Build-up of material at the kerb indicated material being thrown across the road by the traffic. Coarser particles were resuspended faster than the finer ones. A clear decay profile was seen in the case of particles larger than 2μm; particles smaller than 2μm did not show any decay pattern during the experiment duration. Grinding of material appears to control the reservoir of fine particles on the road surface. The amount of material resuspended by traffic is about 30% less than those removed along the road and a factor of 6 higher than the amount removed across the road. Resuspension accounts for 40% of the total material removed from a road segment and 70% of the material removed together along and across the road. On average a single vehicle pass removes 0.08% of material present on a road segment at that instant. The calculation scheme is obtained from a short-duration study and therefore further studies of long duration involving varying road geometry and different traffic and meteorological condition need to be carried out before applying parameter estimates presented in this paper.

A GIS-based atmospheric dispersion model for pollutants emitted by complex source areas.

Science.gov (United States)

Teggi, Sergio; Costanzini, Sofia; Ghermandi, Grazia; Malagoli, Carlotta; Vinceti, Marco

2018-01-01

Gaussian dispersion models are widely used to simulate the concentrations and deposition fluxes of pollutants emitted by source areas. Very often, the calculation time limits the number of sources and receptors and the geometry of the sources must be simple and without holes. This paper presents CAREA, a new GIS-based Gaussian model for complex source areas. CAREA was coded in the Python language, and is largely based on a simplified formulation of the very popular and recognized AERMOD model. The model allows users to define in a GIS environment thousands of gridded or scattered receptors and thousands of complex sources with hundreds of vertices and holes. CAREA computes ground level, or near ground level, concentrations and dry deposition fluxes of pollutants. The input/output and the runs of the model can be completely managed in GIS environment (e.g. inside a GIS project). The paper presents the CAREA formulation and its applications to very complex test cases. The tests shows that the processing time are satisfactory and that the definition of sources and receptors and the output retrieval are quite easy in a GIS environment. CAREA and AERMOD are compared using simple and reproducible test cases. The comparison shows that CAREA satisfactorily reproduces AERMOD simulations and is considerably faster than AERMOD. Copyright © 2017 Elsevier B.V. All rights reserved.

On-Road Chemical Transformation as an Important Mechanism of NO2 Formation

Science.gov (United States)

Nitrogen dioxide (NO2) not only is linked with a number of adverse effects on the respiratory system, but also contributes to the formation of ground-level ozone (O3) and fine particulate matter (PM2.5) pollution. NO2 levels near major roads have been monitored as part of the one...

Community-Based Decision-Making: Application of Web-Based Near-Road Modeling System to Newport News, Virginia

Science.gov (United States)

Living, working, and going to school near roadways has been associated with a number of adverse health effects, including asthma exacerbation, cardiovascular impairment, and respiratory symptoms. In the United States, 30% - 45% of urban populations live or work in the near-road e...

Comparison of numerical models for calculating dispersion from accidental releases of pollutants

Energy Technology Data Exchange (ETDEWEB)

Pepper, D W [Savannah River Lab., Aiken, SC; Cooper, R E; Baker, A J

1982-01-01

A modular, data-based system approach has been developed to facilitate computational simulation of multi-dimensional pollutant dispersion in atmospheric, steam, estuary, and groundwater applications. This system is used to assess effects of accidental releases of pollutants to the environment. Model sophistication ranges from simple statistical to complex three-dimensional numerical methods. The system used specifies desired degree of model sophistication from a terminal. The model used depends on the particular type of problem being solved, and on a basis of merit related to computer cost. The results of prediction for several model problems are presented.

Proximity of public elementary schools to major roads in Canadian urban areas.

Science.gov (United States)

Amram, Ofer; Abernethy, Rebecca; Brauer, Michael; Davies, Hugh; Allen, Ryan W

2011-12-21

Epidemiologic studies have linked exposure to traffic-generated air and noise pollution with a wide range of adverse health effects in children. Children spend a large portion of time at school, and both air pollution and noise are elevated in close proximity to roads, so school location may be an important determinant of exposure. No studies have yet examined the proximity of schools to major roads in Canadian cities. Data on public elementary schools in Canada's 10 most populous cities were obtained from online databases. School addresses were geocoded and proximity to the nearest major road, defined using a standardized national road classification scheme, was calculated for each school. Based on measurements of nitrogen oxide concentrations, ultrafine particle counts, and noise levels in three Canadian cities we conservatively defined distances roads as the zone of primary interest. Census data at the city and neighborhood levels were used to evaluate relationships between school proximity to major roads, urban density, and indicators of socioeconomic status. Addresses were obtained for 1,556 public elementary schools, 95% of which were successfully geocoded. Across all 10 cities, 16.3% of schools were located within 75 m of a major road, with wide variability between cities. Schools in neighborhoods with higher median income were less likely to be near major roads (OR per $20,000 increase: 0.81; 95% CI: 0.65, 1.00), while schools in densely populated neighborhoods were more frequently close to major roads (OR per 1,000 dwellings/km²: 1.07; 95% CI: 1.00, 1.16). Over 22% of schools in the lowest neighborhood income quintile were close to major roads, compared to 13% of schools in the highest income quintile. A substantial fraction of students at public elementary schools in Canada, particularly students attending schools in low income neighborhoods, may be exposed to elevated levels of air pollution and noise while at school. As a result, the locations of

Inventory and Policy Reduction Potential of Greenhouse Gas and Pollutant Emissions of Road Transportation Industry in China

Directory of Open Access Journals (Sweden)

Ye Li

2016-11-01

Full Text Available In recent years, emissions from the road transportation industry in China have been increasing rapidly. To evaluate the reduction potential of greenhouse gas and pollutant emissions of the industry in China, its emission inventory was calculated and scenario analysis was created for the period between 2012 and 2030 in this paper. Based on the Long-range Energy Alternatives Planning System (LEAP model, the development of China’s road transportation industry in two scenarios (the business-as-usual (BAU scenario and the comprehensive-mitigation (CM scenario was simulated. In the Comprehensive Mitigation scenario, there are nine various measures which include Fuel Economy Standards, Auto Emission Standards, Energy-saving Technology, Tax Policy, Eco-driving, Logistics Informatization, Vehicle Liquidation, Electric Vehicles, and Alternative Fuels. The cumulative energy and emission reductions of these specific measures were evaluated. Our results demonstrate that China’s road transportation produced 881 million metric tons of CO2 and emitted 1420 thousand tons of CO, 2150 thousand tons of NOx, 148 thousand tons of PM10, and 745 thousand tons of HC in 2012. The reduction potential is quite large, and road freight transportation is the key mitigation subsector, accounting for 85%–92% of the total emission. For energy conservation and carbon emission mitigation, logistics informatization is the most effective method, potentially reducing 1.80 billion tons of coal equivalent and 3.83 billion tons of CO2 from 2012 to 2030. In terms of air pollutant emission mitigation, the auto emission standards measure performs best with respect to NOx, PM10, and HC emission mitigation, and logistic informatization measure is the best in CO emission reduction. In order to maximize the mitigation potential of China’s road transportation industry, the government needs to implement various measures in a timely and strict fashion.

Numerical modeling of flow and pollutant dispersion in street canyons with tree planting

NARCIS (Netherlands)

Balczó, M.; Gromke, C.B.; Ruck, B.

2009-01-01

Numerical simulations of the impact of tree planting on airflow and traffic pollutant dispersion in urban street canyons have been performed using the commercial CFD (Computational Fluid Dynamics) code MISKAM. A k-e turbulence model including additional terms for the treatment of vegetation, has

Stormwater Pollution Prevention Plan - TA-60 Roads and Grounds Facility and Associated Sigma Mesa Staging Area

Energy Technology Data Exchange (ETDEWEB)

Sandoval, Leonard Frank [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

2018-01-31

This Storm Water Pollution Prevention Plan (SWPPP) was developed in accordance with the provisions of the Clean Water Act (33 U.S.C. §§1251 et seq., as amended), and the Multi-Sector General Permit for Storm Water Discharges Associated with Industrial Activity (U.S. EPA, June 2015) issued by the U.S. Environmental Protection Agency (EPA) for the National Pollutant Discharge Elimination System (NPDES) and using the industry specific permit requirements for Sector P-Land Transportation and Warehousing as a guide. This SWPPP applies to discharges of stormwater from the operational areas of the TA-60 Roads and Grounds and Associated Sigma Mesa Staging Area at Los Alamos National Laboratory. Los Alamos National Laboratory (also referred to as LANL or the “Laboratory”) is owned by the Department of Energy (DOE), and is operated by Los Alamos National Security, LLC (LANS). Throughout this document, the term “facility” refers to the TA-60 Roads and Grounds and Associated Sigma Mesa Staging Area. The current permit expires at midnight on June 4, 2020.

Zoning Of Pollutant Dispersion Came From IJEN Crater In The Downstream Region Of BANYUPUTIH River Using Oxygen-18 (18O) Natural Isotope Technique

International Nuclear Information System (INIS)

Susiati, Heni; Yarianto, S.B.S.; Sjarmufni, A.; Suprijadi; Wibagyo

2002-01-01

The research should be arranged for natural isotope composition of Oxygen-18 ( 18 O) in the water catchments of Banyupahit -Banyuputih river. Aim of the research are determine zoning of pollutant dispersion and be clarified that the pollution really come from lien crater as more surely above mentioned by the result of investigation previously. Research method be used field survey and characteristic analysis of Oksigen-18 isotope. Zoning of pollutant dispersion in the downstream side covers settlement. agricultural, plantation, and sugar factory area have conducted by analyzing Oksigen-18 isotope characteristic. Based on the result of the research pollutant dispersion area in the downstream region. the Eastern side of water catchments area were categorized as pollution level l was more dominant rather than in the Western side and pollution level II came from water pound area of Banyuputih. This phenomena caused of an irrigation system using by Liwung Water Pound of Banyuputih river which should be polluted by Sulfur. Geological factor in the Eastern (lithology) were most of sand rock also induce the dispersion of Sulfur rather than in the Western area. Present research has clarified previous investigation that Banyupahit river were polluted by Sulfur as a result of ijen crater leakage

An assessment of dispersing pollutants from the pre-harvest burning of sugarcane in rural areas in the northeast of Brazil

Science.gov (United States)

Rangel, Maria Gabriela L.; Henríquez, Jorge R.; Costa, José A. P.; de Lira Junior, José C.

2018-04-01

In recent years, the Brazilian government has been applying several restrictions with regard to preventing environmental pollution. Although Brazilian legislation is becoming stricter as to the pre-harvest burning of sugarcane, this practice is frequently used in order to assist manual harvesting. In the northeast region of Brazil, sugarcane is an important crop, which accounts for about 15% of the national production in a total area of 1,060,660 ha, the average production being 51,119 kg per hectare. The pre-harvest burning of sugarcane generates smoke, which has a high concentration of atmospheric pollutants such as carbon dioxide (CO2), carbon monoxide (CO), particulate matter (P.M. 2.5 and 10), polycyclic aromatic hydrocarbons (PAH), volatile organic compounds (VOC) and nitrogen oxides (NOX). This article estimates the volume of CO, P.M. 2.5 and NOX generated and how they are dispersed in the atmosphere when this arises from the burning of sugarcane biomass in rural areas of Northeast Brazil, and does so by using AERMOD VIEW® simulation software. Using the characteristics of the emissions and environmental (meteorological and topographical) data, quality air profiles based on pollutant dispersion were obtained. Three studies were taken into account in order to determine the relationship between pollutant dispersion and some parameters of the burning process, such as those for the spatial distribution of resources, the duration of pre-harvest burning and the influence of undertaking burning in different months. As to spatial distribution, to divide an area into small lots contributes to decreasing the maximum concentration of pollutants by 53% compared to burning a single area of equivalent size. The study of the burning duration indicated that doing so gradually (using a lengthier procedure) could decrease the maximum concentration of the pollutants by an inverse relation. The harvesting period in this region is between November and April. The pollutants

An experimental study of the impact of trees and urban form on the turbulent dispersion of heavy particles from near ground point sources

Science.gov (United States)

Stoll, R., II; Christen, A.; Mahaffee, W.; Salesky, S.; Therias, A.; Caitlin, S.

2017-12-01

Pollution in the form of small particles has a strong impact on a wide variety of urban processes that play an important role in the function of urban ecosystems and ultimately human health and well-being. As a result, a substantial body of research exists on the sources, sinks, and transport characteristics of urban particulate matter. Most of the existing experimental work examining point sources employed gases (e.g., SF6) as the working medium. Furthermore, the focus of most studies has been on the dispersion of pollutants far from the source location. Here, our focus is on the turbulent dispersion of heavy particles in the near source region of a suburban neighborhood. To this end, we conducted a series of heavy particle releases in the Sunset neighborhood of Vancouver, Canada during June, 2017. The particles where dispersed from a near ground point source at two different locations. The Sunset neighborhood is composed mostly of single dwelling detached houses and has been used in numerous previous urban studies. One of the release points was just upwind of a 4-way intersection and the other in the middle of a contiguous block of houses. Each location had a significant density of trees. A minimum of four different successful release events were conducted at each site. During each release, fluorescing micro particles (mean diameter approx. 30 micron) were released from ultrasonic atomizer nozzles for a duration of approximately 20 minutes. The particles where sampled at 50 locations (1.5 m height) in the area downwind of the release over distances from 1-15 times the mean canopy height ( 6 m) using rotating impaction traps. In addition to the 50 sampler locations, instantaneous wind velocities were measured with eight sonic anemometers distributed horizontally and vertically throughout the release area. The resulting particle plume distributions indicate a strong impact of local urban form in the near source region and a high degree of sensitivity to the local

On the Pollutant Plume Dispersion in the Urban Canopy Layer over 2D Idealized Street Canyons: A Large-Eddy Simulation Approach

Science.gov (United States)

Wong, Colman C. C.; Liu, Chun-Ho

2010-05-01

Anthropogenic emissions are the major sources of air pollutants in urban areas. To improve the air quality in dense and mega cities, a simple but reliable prediction method is necessary. In the last five decades, the Gaussian pollutant plume model has been widely used for the estimation of air pollutant distribution in the atmospheric boundary layer (ABL) in an operational manner. Whereas, it was originally designed for rural areas with rather open and flat terrain. The recirculating flows below the urban canopy layer substantially modify the near-ground urban wind environment and so does the pollutant distribution. Though the plume height and dispersion are often adjusted empirically, the accuracy of applying the Gaussian pollutant plume model in urban areas, of which the bottom of the flow domain consists of numerous inhomogeneous buildings, is unclear. To elucidate the flow and pollutant transport, as well as to demystify the uncertainty of employing the Gaussian pollutant plume model over urban roughness, this study was performed to examine how the Gaussian-shape pollutant plume in the urban canopy layer is modified by the idealized two-dimensional (2D) street canyons at the bottom of the ABL. The specific objective is to develop a parameterization so that the geometric effects of urban morphology on the operational pollutant plume dispersion models could be taken into account. Because atmospheric turbulence is the major means of pollutant removal from street canyons to the ABL, the large-eddy simulation (LES) was adopted to calculate explicitly the flows and pollutant transport in the urban canopy layer. The subgrid-scale (SGS) turbulent kinetic energy (TKE) conservation was used to model the SGS processes in the incompressible, isothermal conditions. The computational domain consists of 12 identical idealized street canyons of unity aspect ratio which were placed evenly in the streamwise direction. Periodic boundary conditions (BCs) for the flow were applied

Applicability of the Environmental Relative Moldiness Index for Quantification of Residential Mold Contamination in an Air Pollution Health Effects Study

Science.gov (United States)

As part of the Near-Road Exposures and Effects of Urban Air Pollutants Study (NEXUS) investigating the respiratory health impacts of traffic-related air pollutants on asthmatic children in Detroit, Michigan, residential dust samples were collected to quantify mold exposure. Sett...

Rapid Assessment of Environmental Health Impacts for Policy Support: The Example of Road Transport in New Zealand

Directory of Open Access Journals (Sweden)

David Briggs

2015-12-01

Full Text Available An integrated environmental health impact assessment of road transport in New Zealand was carried out, using a rapid assessment. The disease and injury burden was assessed from traffic-related accidents, air pollution, noise and physical (inactivity, and impacts attributed back to modal source. In total, road transport was found to be responsible for 650 deaths in 2012 (2.1% of annual mortality: 308 from traffic accidents, 283 as a result of air pollution, and 59 from noise. Together with morbidity, these represent a total burden of disease of 26,610 disability-adjusted life years (DALYs. An estimated 40 deaths and 1874 DALYs were avoided through active transport. Cars are responsible for about 52% of attributable deaths, but heavy goods vehicles (6% of vehicle kilometres travelled, vkt accounted for 21% of deaths. Motorcycles (1 per cent of vkt are implicated in nearly 8% of deaths. Overall, impacts of traffic-related air pollution and noise are low compared to other developed countries, but road accident rates are high. Results highlight the need for policies targeted at road accidents, and especially at heavy goods vehicles and motorcycles, along with more general action to reduce the reliance on private road transport. The study also provides a framework for national indicator development.

Evaluation of different numerical methodologies for dispersion of air pollutants in an urban environment

International Nuclear Information System (INIS)

Mumovic, D.; Crowther, J.M.; Stevanovic, Z.

2003-01-01

Since 1950 the world population has more than doubled but meanwhile the global number of cars has increased by a factor of 10. In that same period the fraction of people living in urban areas has increased by a factor of 4. Apart from large point-sources of local air pollution, traffic induced pollution is now the most significant contributor to urban air quality in city centres, particularly for carbon monoxide, oxides of nitrogen and fine particulate matter. Until recently, pollutant dispersion in urban areas has usually been numerically investigated by using empirical models, such as the Gaussian plume model, or by extensions of this technique to line sources and multiple sources. More recently, advanced computational fluid dynamics (CFD) simulations have been attempted but have been mainly two-dimensional and often encompassing only a single street canyon. This paper provides a comprehensive, critical evaluation of dispersion of pollutants in urban areas. A three-dimensional flow model has been set-up for a staggered crossroad, using the Navier-Stokes equations and the conservation equation for species concentration. The effect of using several different turbulence models, including the k-ε model, modifications and extensions, has been investigated. Cartesian coordinates have been used in connection with the Partial Solution Algorithm (PARSOL) and Body Fitted Coordinates (BFC). The effects of several different numerical algorithms for discretization of differential equations have also been studied. More than thirty cases are analysed, and the main results are compared with wind tunnel experiments. The numerical results are presented as non-dimensional values to facilitate comparison between experimental and numerical studies. It has been shown that the numerical studies have been able to simulate the air-flow in urban areas and confirm, qualitatively, the previous field observations and wind tunnel results. This success encouraged the authors to extend such

Evaluation of different numerical methodologies for dispersion of air pollutants in an urban environment

Energy Technology Data Exchange (ETDEWEB)

Mumovic, D.; Crowther, J.M. [Glasgow Caledonian Univ., School of Built and Natural Environment, Glasgow (United Kingdom)]. E-mail: dmumov10@caledonian.ac.uk; Stevanovic, Z. [Univ. of Belgrade, Inst. of Nuclear Sciences, Belgrade (Serbia and Montenegro)

2003-07-01

Since 1950 the world population has more than doubled but meanwhile the global number of cars has increased by a factor of 10. In that same period the fraction of people living in urban areas has increased by a factor of 4. Apart from large point-sources of local air pollution, traffic induced pollution is now the most significant contributor to urban air quality in city centres, particularly for carbon monoxide, oxides of nitrogen and fine particulate matter. Until recently, pollutant dispersion in urban areas has usually been numerically investigated by using empirical models, such as the Gaussian plume model, or by extensions of this technique to line sources and multiple sources. More recently, advanced computational fluid dynamics (CFD) simulations have been attempted but have been mainly two-dimensional and often encompassing only a single street canyon. This paper provides a comprehensive, critical evaluation of dispersion of pollutants in urban areas. A three-dimensional flow model has been set-up for a staggered crossroad, using the Navier-Stokes equations and the conservation equation for species concentration. The effect of using several different turbulence models, including the k-{epsilon} model, modifications and extensions, has been investigated. Cartesian coordinates have been used in connection with the Partial Solution Algorithm (PARSOL) and Body Fitted Coordinates (BFC). The effects of several different numerical algorithms for discretization of differential equations have also been studied. More than thirty cases are analysed, and the main results are compared with wind tunnel experiments. The numerical results are presented as non-dimensional values to facilitate comparison between experimental and numerical studies. It has been shown that the numerical studies have been able to simulate the air-flow in urban areas and confirm, qualitatively, the previous field observations and wind tunnel results. This success encouraged the authors to extend

Energy dispersion X-ray fluorescence techniques in water pollution analysis

International Nuclear Information System (INIS)

Holynska, B.

1980-01-01

Advantages and limitations of energy dispersion X-ray fluorescence methods for analysis of pollutants in water are discussed. The necessary equipment for X-ray measurement of insoluble and dissolved trace metals in water is described. Different techniques of enrichment of trace metals are presented: ion exchange on selective Chelex-100 exchanger, precipitation with chelating agents DDTC and APDC, and adsorption on activated carbon. Some results obtained using different preconcentration methods for trace metals determination in different waters are presented. (author)

The Interplay of Climate Change and Air Pollution on Health

OpenAIRE

Orru, H.; Ebi, K. L.; Forsberg, B.

2017-01-01

Purpose of review: Air pollution significantly affects health, causing up to 7 million premature deaths annually with an even larger number of hospitalizations and days of sick leave. Climate change could alter the dispersion of primary pollutants, particularly particulate matter, and intensify the formation of secondary pollutants, such as near-surface ozone. The purpose of the review is to evaluate the recent evidence on the impacts of climate change on air pollution and air pollution-relat...

Relationship between rooftop and on-road concentrations of traffic-related pollutants in a busy street canyon: Ambient wind effects

International Nuclear Information System (INIS)

Kwak, Kyung-Hwan; Lee, Sang-Hyun; Seo, Jaemyeong Mango; Park, Seung-Bu; Baik, Jong-Jin

2016-01-01

Rooftop and on-road measurements of O_3, NO_2, NO_x, and CO concentrations were conducted to investigate the relationship between rooftop and on-road concentrations in a busy and shallow street canyon with an aspect ratio of ∼0.3 in Seoul, Republic of Korea, from 15 April to 1 May 2014. The median road-to-roof concentration ratios, correlation coefficients between rooftop and on-road concentrations, and temporal variations of rooftop and on-road concentrations are analyzed according to the rooftop wind directions which are two cross-canyon and two along-canyon directions. The analysis results indicate that the relationship is strong when the rooftop is situated on the downwind side rather than on the upwind side. Relative to the cross-canyon wind directions, one of the along-canyon wind directions can more enhance the relationship. A conceptual framework is proposed to explain the effect of ambient wind direction on the relationship between rooftop and on-road concentrations in a street canyon. - One of the along-canyon wind directions can enhance the relationship between rooftop and on-road concentrations of traffic-related pollutants in a busy and shallow street canyon.

Roads, interrupted dispersal, and genetic diversity in timber rattlesnakes.

Science.gov (United States)

Clark, Rulon W; Brown, William S; Stechert, Randy; Zamudio, Kelly R

2010-08-01

Anthropogenic habitat modification often creates barriers to animal movement, transforming formerly contiguous habitat into a patchwork of habitat islands with low connectivity. Roadways are a feature of most landscapes that can act as barriers or filters to migration among local populations. Even small and recently constructed roads can have a significant impact on population genetic structure of some species, but not others. We developed a research approach that combines fine-scale molecular genetics with behavioral and ecological data to understand the impacts of roads on population structure and connectivity. We used microsatellite markers to characterize genetic variation within and among populations of timber rattlesnakes (Crotalus horridus) occupying communal hibernacula (dens) in regions bisected by roadways. We examined the impact of roads on seasonal migration, genetic diversity, and gene flow among populations. Snakes in hibernacula isolated by roads had significantly lower genetic diversity and higher genetic differentiation than snakes in hibernacula in contiguous habitat. Genetic-assignment analyses revealed that interruption to seasonal migration was the mechanism underlying these patterns. Our results underscore the sizeable impact of roads on this species, despite their relatively recent construction at our study sites (7 to 10 generations of rattlesnakes), the utility of population genetics for studies of road ecology, and the need for mitigating effects of roads.

Phenology of a Vegetation Barrier and Resulting Impacts on Near-Highway Particle Number and Black Carbon Concentrations on a School Campus

Directory of Open Access Journals (Sweden)

Christina H. Fuller

2017-02-01

Full Text Available Traffic-related air pollution is a persistent concern especially in urban areas where populations live in close proximity to roadways. Innovative solutions are needed to minimize human exposure and the installation of vegetative barriers shows potential as a method to reduce near-road concentrations. This study investigates the impact of an existing stand of deciduous and evergreen trees on near-road total particle number (PNC and black carbon (BC concentrations across three seasons. Measurements were taken during spring, fall and winter on the campus of a middle school in the Atlanta (GA, USA area at distances of 10 m and 50 m from a major interstate highway. We identified consistent decreases in BC concentrations, but not for PNC, with increased distance from the highway. In multivariable models, hour of day, downwind conditions, distance to highway, temperature and relative humidity significantly predicted pollutant concentrations. The magnitude of effect of these variables differed by season, however, we were not able to show a definitive impact of the vegetative barrier on near-road concentrations. More detailed studies are necessary to further examine the specific configurations and scenarios that may produce pollutant and exposure reductions.

Numerical modeling of flows and pollutant dispersion within and above urban street canyons under unstable thermal stratification by large-eddy simulation

Science.gov (United States)

Chan, Ming-Chung; Liu, Chun-Ho

2013-04-01

Recently, with the ever increasing urban areas in developing countries, the problem of air pollution due to vehicular exhaust arouses the concern of different groups of people. Understanding how different factors, such as urban morphology, meteorological conditions and human activities, affect the characteristics of street canyon ventilation, pollutant dispersion above urban areas and pollutant re-entrainment from the shear layer can help us improve air pollution control strategies. Among the factors mentioned above, thermal stratification is a significant one determining the pollutant transport behaviors in certain situation, e.g. when the urban surface is heated by strong solar radiation, which, however, is still not widely explored. The objective of this study is to gain an in-depth understanding of the effects of unstable thermal stratification on the flows and pollutant dispersion within and above urban street canyons through numerical modeling using large-eddy simulation (LES). In this study, LES equipped with one-equation subgrid-scale (SGS) model is employed to model the flows and pollutant dispersion within and above two-dimensional (2D) urban street canyons (flanked by idealized buildings, which are square solid bars in these models) under different intensities of unstable thermal stratifications. Three building-height-to-street-width (aspect) ratios, 0.5, 1 and 2, are included in this study as a representation of different building densities. The prevailing wind flow above the urban canopy is driven by background pressure gradient, which is perpendicular to the street axis, while the condition of unstable thermal stratification is induced by applying a higher uniform temperature on the no-slip urban surface. The relative importance between stratification and background wind is characterized by the Richardson number, with zero value as a neutral case and negative value as an unstable case. The buoyancy force is modeled by Boussinesq approximation and the

Heavy metal contents of road-deposited sediment along the urban-rural gradient around Beijing and its potential contribution to runoff pollution.

Science.gov (United States)

Zhao, Hongtao; Li, Xuyong; Wang, Xiaomei

2011-09-01

Understanding the contribution of road-deposited sediment (RDS) and its washoff process is essential for controlling urban runoff pollution. Ninety-seven RDS samples were collected along the urban-suburban-rural gradient from areas of five administrative units in the Beijing metropolitan region, including central urban (UCA), urban village (UVA), central suburban county (CSA), rural town (RTA), and rural village (RVA) areas. RDS washoff was evaluated with different particle sizes using a rainfall simulator. Heavy metal elements (i.e., Cr, Cu, Ni, Pb, and Zn) were estimated in both RDS and runoff samples. The RDS mass per unit area increased in the order UCA (21 ± 24 g/m(2)) ≈ CSA (20 ± 16 g/m(2)) runoff pollution contributions per unit area. Our findings imply that controlling the first flush in the UCA and CSA, and improving existing street cleaning methods and road surface conditions in the TRA, UVA, and RVA will be appropriate strategies for controlling runoff pollution from RDS.

EnviroAtlas - Sum of population near roads without tree buffer for the conterminous United States

Data.gov (United States)

U.S. Environmental Protection Agency — This EnviroAtlas dataset is a summary of total population near major roads without any tree buffer within 12-digit Hydrologic Units (HUC_12), based on the National...

Environmental exposure of road borders to zinc

International Nuclear Information System (INIS)

Blok, J.

2005-01-01

The emissions of zinc along roads originating from tyre wear, corrosion of safety fence and other traffic-related sources have been quantified and validated by measured long-term loads in road run-off and airborne solids (drift) for 29 published case studies. The distribution pattern over the road border at various distances from the edge of the paved surface is assessed on the basis of 38 published case studies with measured concentrations in soil. For the impact assessment, the road border is differentiated into a zone that is part of the 'technosphere' and the 'target zone' beyond that technosphere that can be considered as part of the receiving environment. The 'technosphere' of the road includes the central reservation, the hard and the soft shoulder or, if one or both shoulders are not present, the so-called obstacle 'free zone' that is defined by road engineers. Pollution within the technosphere may require appropriate management of solid disposal and isolation from groundwater to prevent further distribution of pollutants to the environment. In the target zone along regional roads, the zinc load is about 4 mg/m 2 year and this is of the same order of magnitude as that of atmospheric deposition in areas beyond the influence of roads (background). In the target zone along highways, the zinc load is increased in comparison to the background deposition. The average load of about 38 mg/m 2 year is similar to that in fertilised agricultural land. Because most of the emitted zinc stays in the technosphere, the total amount entering this target zone along highways is limited. From the 140 tons of zinc per year that is released from tyre wear in The Netherlands, 64 tons is emitted in the urban area, 6.5 tons reaches to the target zones of all roads and only 1.1 tons of zinc will enter the target zone along highways. This amount will be further decreased by the application of porous asphalt in the near future. The emission from safety fence corrosion does not enter

Road traffic noise and incident myocardial infarction

DEFF Research Database (Denmark)

Sørensen, Mette; Andersen, Zorana Jovanovic; Nordsborg, Rikke B

2012-01-01

Both road traffic noise and ambient air pollution have been associated with risk for ischemic heart disease, but only few inconsistent studies include both exposures.......Both road traffic noise and ambient air pollution have been associated with risk for ischemic heart disease, but only few inconsistent studies include both exposures....

Ranking current and prospective NO2 pollution mitigation strategies: An environmental and economic modelling investigation in Oxford Street, London.

Science.gov (United States)

Jeanjean, A P R; Gallagher, J; Monks, P S; Leigh, R J

2017-06-01

Air pollution continues to be a problem in the urban environment. A range of different pollutant mitigation strategies that promote dispersion and deposition exist, but there is little evidence with respect to their comparative performance from both an environmental and economic perspective. This paper focuses on examining different NO 2 mitigation strategies such as trees, buildings facades coated with photocatalytic paint and solid barriers in Oxford Street in London. The case study findings will support ranking the environmental and economic impacts of these different strategies to improve personal exposure conditions on the footpath and on the road in a real urban street canyon. CFD simulations of airflow and NO 2 dispersion in Oxford Street in London were undertaken using the OpenFOAM software platform with the k-ε model, taking into account local prevailing wind conditions. Trees are shown to be the most cost-effective strategy, with a small reduction in NO 2 concentrations of up to 0.7% on the road. However, solid barriers with and without the application of photocatalytic paint and an innovative material (20 times more expensive than trees) can improve air quality on the footpaths more substantially, up to 7.4%, yet this has a significant detrimental impact on NO 2 concentrations (≤23.8%) on the road. Photocatalytic paint on building surfaces presented a minimal environmental reductions (1.2%) and economic (>100 times more expensive than trees) mitigation strategy. The findings recognised the differences between footpath and road concentrations occurred and that a focused examination of three pollution hotspots can provide more cost effective pollution mitigation. This study considers how a number of pollutant mitigation measures can be applied in a single street canyon and demonstrates the strengths and weaknesses of these strategies from economic and environmental perspectives. Further research is required to extrapolate the findings presented here to

Algorithms and analytical solutions for rapidly approximating long-term dispersion from line and area sources

Science.gov (United States)

Barrett, Steven R. H.; Britter, Rex E.

Predicting long-term mean pollutant concentrations in the vicinity of airports, roads and other industrial sources are frequently of concern in regulatory and public health contexts. Many emissions are represented geometrically as ground-level line or area sources. Well developed modelling tools such as AERMOD and ADMS are able to model dispersion from finite (i.e. non-point) sources with considerable accuracy, drawing upon an up-to-date understanding of boundary layer behaviour. Due to mathematical difficulties associated with line and area sources, computationally expensive numerical integration schemes have been developed. For example, some models decompose area sources into a large number of line sources orthogonal to the mean wind direction, for which an analytical (Gaussian) solution exists. Models also employ a time-series approach, which involves computing mean pollutant concentrations for every hour over one or more years of meteorological data. This can give rise to computer runtimes of several days for assessment of a site. While this may be acceptable for assessment of a single industrial complex, airport, etc., this level of computational cost precludes national or international policy assessments at the level of detail available with dispersion modelling. In this paper, we extend previous work [S.R.H. Barrett, R.E. Britter, 2008. Development of algorithms and approximations for rapid operational air quality modelling. Atmospheric Environment 42 (2008) 8105-8111] to line and area sources. We introduce approximations which allow for the development of new analytical solutions for long-term mean dispersion from line and area sources, based on hypergeometric functions. We describe how these solutions can be parameterized from a single point source run from an existing advanced dispersion model, thereby accounting for all processes modelled in the more costly algorithms. The parameterization method combined with the analytical solutions for long-term mean

CALCULATION OF POLLUTION DYNAMICS NEAR RAILWAY TERRITORY DURING COAL TRANSPORTATION

Directory of Open Access Journals (Sweden)

M. M. Biliaiev

2017-02-01

Full Text Available Purpose. The article is aimed to develop 3D numerical model for the prediction of atmospheric pollution during transportation of bulk cargo in the railway car. Methodology.To solve this problem, it was developed three-dimensional numerical model, based on the use of the transport equation of dust pollution in the air by the wind and atmospheric turbulent diffusion. For the numerical integration of the simulating equation of the dust transport the implicit difference scheme was used. When constructing a difference scheme, it was carried out prior splitting of the original transport equation into the sequence of solutions of three equations. The first of them takes into account the transport of dust in paths, the second equation – dust transport under the influence of atmospheric turbulent diffusion, and the third equation –change of the dust concentration in the air due to its emissions from the cars.Unknown value of the pollutant concentration at every step of splitting is determined by the explicit scheme – the method of running account, which provides a simple numerical implementation of splitting equations. The developed numerical model is the basis for specialized computer program. On the basis of the constructed numerical model we carried out a computational experiment to assess the level of air pollution at the railway station during the motion of train with coal. Findings. Authors developed 3D numerical model, which belongs to the class of «screening models». This model takes into account the main physical factors affecting the process of dispersion of dust pollution in the atmosphere during coal transportation. The proposed numerical model requires low cost of computer time in the practical implementation on small and medium-power computers. This model can be used for rapid calculations of the dynamics of air pollution when transporting coal by rail. Calculations to determine the pollutant concentration and formation of the

Proximity of public elementary schools to major roads in Canadian urban areas

Directory of Open Access Journals (Sweden)

Amram Ofer

2011-12-01

Full Text Available Abstract Background Epidemiologic studies have linked exposure to traffic-generated air and noise pollution with a wide range of adverse health effects in children. Children spend a large portion of time at school, and both air pollution and noise are elevated in close proximity to roads, so school location may be an important determinant of exposure. No studies have yet examined the proximity of schools to major roads in Canadian cities. Methods Data on public elementary schools in Canada's 10 most populous cities were obtained from online databases. School addresses were geocoded and proximity to the nearest major road, defined using a standardized national road classification scheme, was calculated for each school. Based on measurements of nitrogen oxide concentrations, ultrafine particle counts, and noise levels in three Canadian cities we conservatively defined distances Results Addresses were obtained for 1,556 public elementary schools, 95% of which were successfully geocoded. Across all 10 cities, 16.3% of schools were located within 75 m of a major road, with wide variability between cities. Schools in neighborhoods with higher median income were less likely to be near major roads (OR per $20,000 increase: 0.81; 95% CI: 0.65, 1.00, while schools in densely populated neighborhoods were more frequently close to major roads (OR per 1,000 dwellings/km2: 1.07; 95% CI: 1.00, 1.16. Over 22% of schools in the lowest neighborhood income quintile were close to major roads, compared to 13% of schools in the highest income quintile. Conclusions A substantial fraction of students at public elementary schools in Canada, particularly students attending schools in low income neighborhoods, may be exposed to elevated levels of air pollution and noise while at school. As a result, the locations of schools may negatively impact the healthy development and academic performance of a large number of Canadian children.

Metal exposure and effects in voles and small birds near a mining haul road in Cape Krusenstern National Monument, Alaska.

Science.gov (United States)

Brumbaugh, William G; Mora, Miguel A; May, Thomas W; Phalen, David N

2010-11-01

Voles and small passerine birds were live-captured near the Delong Mountain Regional Transportation System (DMTS) haul road in Cape Krusenstern National Monument in northwest Alaska to assess metals exposure and sub-lethal biological effects. Similar numbers of animals were captured from a reference site in southern Cape Krusenstern National Monument for comparison. Histopathological examination of selected organs, and analysis of cadmium, lead, and zinc concentrations in liver and blood samples were performed. Voles and small birds captured from near the haul road had about 20 times greater blood and liver lead concentrations and about three times greater cadmium concentrations when compared to those from the reference site, but there were no differences in zinc tissue concentrations. One vole had moderate metastatic mineralization of kidney tissue, otherwise we observed no abnormalities in internal organs or DNA damage in the blood of any of the animals. The affected vole also had the greatest liver and blood Cd concentration, indicating that the lesion might have been caused by Cd exposure. Blood and liver lead concentrations in animals captured near the haul road were below concentrations that have been associated with adverse biological effects in other studies; however, subtle effects resulting from lead exposure, such as the suppression of the activity of certain enzymes, cannot be ruled out for some individual animals. Results from our 2006 reconnaissance-level study indicate that overall, voles and small birds obtained from near the DMTS road in Cape Krusenstern National Monument were not adversely affected by metals exposure; however, because of the small sample size and other uncertainties, continued monitoring of lead and cadmium in terrestrial habitats near the DMTS road is advised.

The dispersion characteristics of air pollution from the world's megacities

Directory of Open Access Journals (Sweden)

M. Cassiani

2013-10-01

Full Text Available Megacities are extreme examples of the continuously growing urbanization of the human population that pose (new challenges to the environment and human health at a local scale. However, because of their size megacities also have larger-scale effects, and more research is needed to quantify their regional- and global-scale impacts. We performed a study of the characteristics of pollution plumes dispersing from a group of 36 of the world's megacities using the Lagrangian particle model FLEXPART and focusing on black carbon (BC emissions during the years 2003–2005. BC was selected since it is representative of combustion-related emissions and has a significant role as a short-lived climate forcer. Based on the BC emissions two artificial tracers were modeled: a purely passive tracer and one subject to wet and dry deposition more closely resembling the behavior of a true aerosol. These tracers allowed us to investigate the role of deposition processes in determining the impact of megacities' pollutant plumes. The particles composing the plumes have been sampled in space and time. The time sampling allowed us to investigate the evolution of the plume from its release up to 48 days after emission and to generalize our results for any substance decaying with a timescale sufficiently shorter than the time window of 48 days. The physical characteristics of the time-averaged plume have been investigated, and this showed that, although local conditions are important, overall a city's latitude is the main factor influencing both the local and the regional-to-global dispersion of its pollution. We also repeated the calculations of some of the regional-pollution-potential metrics previously proposed by Lawrence et al. (2007, thus extending their results to a depositing scalar and retaining the evolution in time for all the plumes. Our results agreed well with their previous results despite being obtained using a totally different modeling framework. For the

Eighth joint conference on applications of air pollution meteorology with A & WMA

Energy Technology Data Exchange (ETDEWEB)

NONE

1994-12-31

The eighth Joint Conference on Applications of Air Pollution Meteorology, held January 23-28, 1994, again brings together the American Meteorological Society and Air and Waste Management Association with a broader scientific community to examine the role of the atmosphere on current air quality issues. The CAA Amendments non-attainment title has brought renewed interest in the pairing of complex dynamical meteorological models with photochemical air quality models. Requirements that future attainment to regulations be demonstrated with these models invite a new look at model evaluation. The CAAA titles addressing air toxics have brought renewed interest in near-source dispersion and deposition of toxic chemicals. Consequently, this conference is divided into sessions focusing on topics related to these issues. They include: The Dispersion Environment; Meteorology in Emissions Determination; Long-Range and Mesoscale Pollutant Transport and Fate; Meteorology and Photochemistry; Advanced Dispersion Models and Modeling Systems; Topics in Model Evaluation; Complex Flow Affecting Dispersion Near Structures; and Coastal and Complex Terrain Issues Evaluation.

Energy-latitude dispersion patterns near the isotropy boundaries of energetic protons

Science.gov (United States)

Sergeev, V. A.; Chernyaeva, S. A.; Apatenkov, S. V.; Ganushkina, N. Y.; Dubyagin, S. V.

2015-08-01

Non-adiabatic motion of plasma sheet protons causes pitch-angle scattering and isotropic precipitation to the ionosphere, which forms the proton auroral oval. This mechanism related to current sheet scattering (CSS) provides a specific energy-latitude dispersion pattern near the equatorward boundary of proton isotropic precipitation (isotropy boundary, IB), with precipitation sharply decreasing at higher (lower) latitude for protons with lower (higher) energy. However, this boundary maps to the inner magnetosphere, where wave-induced scattering may provide different dispersion patterns as recently demonstrated by Liang et al. (2014). Motivated by the potential usage of the IBs for the magnetotail monitoring as well as by the need to better understand the mechanisms forming the proton IB, we investigate statistically the details of particle flux patterns near the proton IB using NOAA-POES polar spacecraft observations made during September 2009. By comparing precipitated-to-trapped flux ratio (J0/J90) at >30 and >80 keV proton energies, we found a relatively small number of simple CSS-type dispersion events (only 31 %). The clear reversed (wave-induced) dispersion patterns were very rare (5 %). The most frequent pattern had nearly coinciding IBs at two energies (63 %). The structured precipitation with multiple IBs was very frequent (60 %), that is, with two or more significant J0/J90 dropouts. The average latitudinal width of multiple IB structures was about 1°. Investigation of dozens of paired auroral zone crossings of POES satellites showed that the IB pattern is stable on a timescale of less than 2 min (a few proton bounce periods) but can evolve on a longer (several minutes) scale, suggesting temporal changes in some mesoscale structures in the equatorial magnetosphere. We discuss the possible role of CSS-related and wave-induced mechanisms and their possible coupling to interpret the emerging complicated patterns of proton isotropy boundaries.

Numerical Study of Traffic Pollutant Dispersion within Different Street Canyon Configurations

OpenAIRE

Yucong Miao; Shuhua Liu; Yijia Zheng; Shu Wang; Yuan Li

2014-01-01

The objective of this study is to numerically study flow and traffic exhaust dispersion in urban street canyons with different configurations to find out the urban-planning strategies to ease the air pollution. The Computational Fluid Dynamics (CFD) model used in this study—Open Source Field Operation and Manipulation (OpenFOAM) software package—was firstly validated against the wind-tunnel experiment data by using three different k-ε turbulence models. And then the patterns of flow and dispe...

Depletion velocities for atmospheric pollutants oriented To improve the simplified regional dispersion modelling

International Nuclear Information System (INIS)

Sanchez Gacita, Madeleine; Turtos Carbonell, Leonor; Rivero Oliva, Jose de Jesus

2005-01-01

The present work is aimed to improve externalities assessment using Simplified Methodologies, through the obtaining of depletion velocities for primary pollutants SO 2 , NO X and TSP (Total Suspended Particles) and for sulfate and nitrate aerosols, the secondary pollutants created from the first ones. The main goal proposed was to estimate these values for different cases, in order to have an ensemble of values for the geographic area, among which the most representative could be selected for using it in future studies that appeal to a simplified methodology for the regional dispersion assessment, taking into account the requirements of data, qualified manpower and time for a detailed approach. The results where obtained using detailed studies of the regional dispersion that were conduced for six power facilities, three from Cuba (at the localities of Mariel, Santa Cruz and Tallapiedra) and three from Mexico (at the localities of Tuxpan, Tula and Manzanillo). The depletion velocity for SO 2 was similar for all cases. Results obtained for Tallapiedra, Santa Cruz, Mariel and Manzanillo were similar. For Tula and Tuxpan a high uncertainty was found

Cluster Observations of Ion Dispersions near the Exterior Cusp

Science.gov (United States)

Escoubet, C.; Grison, B.; Berchem, J.; Trattner, K. J.; Pitout, F.; Richard, R. L.; Taylor, M. G.; Laakso, H. E.; Masson, A.; Dunlop, M. W.; Dandouras, I. S.; Reme, H.; Fazakerley, A. N.; Daly, P. W.

2013-12-01

The cusps are the places where the Earth's magnetic field lines, connected to the inner side of the magnetopause, converge. It is therefore the place where signatures of processes occurring near the subsolar point, in the tail lobes, as well as near the dawn and dusk flanks are observed. The main process that injects solar wind plasma into the polar cusp is now generally accepted to be magnetic reconnection. Depending on the IMF direction, this process will take place equatorward (for IMF southward), poleward (for IMF northward) or on the side (for IMF azimuthal) of the cusp. We report a Cluster crossing on 5 January 2002 near the exterior cusp on the southern dusk side. The IMF was mainly azimuthal (IMF-By around -5 nT), the solar wind speed around 280 km/s and the density around 5 cm-3. The four Cluster spacecraft were still in the "magnetotail" configuration with two perfect tetrahedra of 2000 km around apogee and turning into an elongated configuration near the magnetopause. C4 was the first spacecraft to enter the cusp around 19:52:04 UT, followed by C2 at 19:52:35 UT, C1 at 19:54:24 UT and C3 at 20:13:15 UT. C4 and C1 observed two ion energy dispersions at 20:10 UT and 20:40 UT and C3 at 20:35 UT and 21:15 UT. We will investigate the origin of the injections forming the dispersions and if these can be explained by the reconnection between the interplanetary magnetic field and the Earth's magnetic field.

The influence of European pollution on ozone in the Near East and northern Africa

Directory of Open Access Journals (Sweden)

B. N. Duncan

2008-04-01

Full Text Available We present a modeling study of the long-range transport of pollution from Europe, showing that European emissions regularly elevate surface ozone by as much as 20 ppbv in summer in northern Africa and the Near East. European emissions cause 50–150 additional violations per year (i.e. above those that would occur without European pollution of the European health standard for ozone (8-h average >120 μg/m³ or ~60 ppbv in northern Africa and the Near East. We estimate that European ozone pollution is responsible for 50 000 premature mortalities globally each year, of which the majority occurs outside of Europe itself, including 37% (19 000 in northern Africa and the Near East. Much of the pollution from Europe is exported southward at low altitudes in summer to the Mediterranean Sea, northern Africa and the Near East, regions with favorable photochemical environments for ozone production. Our results suggest that assessments of the human health benefits of reducing ozone precursor emissions in Europe should include effects outside of Europe, and that comprehensive planning to improve air quality in northern Africa and the Near East likely needs to address European emissions.

The Influence of European Pollution on Ozone in the Near East and Northern Africa

Science.gov (United States)

Duncan, B. N.; West, J. J.; Yoshida, Y.; Fiore, A. M.; Ziemke, J. R.

2008-01-01

We present a modeling study of the long-range transport of pollution from Europe, showing that European emissions regularly elevate surface ozone by as much as 20 ppbv in summer in northern Africa and the Near East. European emissions cause 50-150 additional violations per year (i.e. above those that would occur without European pollution) of the European health standard for ozone (8-h average greater than 120 micrograms per cubic meters or approximately 60 ppbv) in northern Africa and the Near East. We estimate that European ozone pollution is responsible for 50 000 premature mortalities globally each year, of which the majority occurs outside of Europe itself, including 37% (19 000) in northern Africa and the Near East. Much of the pollution from Europe is exported southward at low altitudes in summer to the Mediterranean Sea, northern Africa and the Near East, regions with favorable photochemical environments for ozone production. Our results suggest that assessments of the human health benefits of reducing ozone precursor emissions in Europe should include effects outside of Europe, and that comprehensive planning to improve air quality in northern Africa and the Near East likely needs to address European emissions.

Review on urban vegetation and particle air pollution - Deposition and dispersion

Science.gov (United States)

Janhäll, Sara

2015-03-01

Urban vegetation affects air quality through influencing pollutant deposition and dispersion. Both processes are described by many existing models and experiments, on-site and in wind tunnels, focussing e.g. on urban street canyons and crossings or vegetation barriers adjacent to traffic sources. There is an urgent need for well-structured experimental data, including detailed empirical descriptions of parameters that are not the explicit focus of the study. This review revealed that design and choice of urban vegetation is crucial when using vegetation as an ecosystem service for air quality improvements. The reduced mixing in trafficked street canyons on adding large trees increases local air pollution levels, while low vegetation close to sources can improve air quality by increasing deposition. Filtration vegetation barriers have to be dense enough to offer large deposition surface area and porous enough to allow penetration, instead of deflection of the air stream above the barrier. The choice between tall or short and dense or sparse vegetation determines the effect on air pollution from different sources and different particle sizes.

Estimating Longitudinal Dispersion Coefficient of Pollutants Using Adaptive Neuro-Fuzzy Inference System

Directory of Open Access Journals (Sweden)

Hossein Riahi Modvar

2008-09-01

Full Text Available Longitudinal dispersion coefficient in rivers and natural streams is usually estimated by simple inaccurate empirical relations because of the complexity of the phenomenon. In this study, the adaptive neuro-fuzzy inference system (ANFIS is used to develop a new flexible tool for predicting the longitudinal dispersion coefficient. The system has the ability to understand and realize the phenomenon without the need for mathematical governing equations.. The training and testing of this new model are accomplished using a set of available published filed data. Several statistical and graphical criteria are used to check the accuracy of the model. The dispersion coefficient values predicted by the ANFIS model compares satisfactorily with the measured data. The predicted values are also compared with those predicted by existing empirical equations reported in the literature to find that the ANFIS model with R2=0.99 and RMSE=15.18 in training stage and R2=0.91 and RMSE=187.8 in testing stage is superior in predicting the dispersion coefficient to the most accurate empirical equation with R2=0.48 and RMSE=295.7. The proposed methodology is a new approach to estimating dispersion coefficient in streams and can be combined with mathematical models of pollutant transfer or real-time updating of these models.

Study of traffic-related pollutant removal from street canyon with trees: dispersion and deposition perspective.

Science.gov (United States)

Morakinyo, Tobi Eniolu; Lam, Yun Fat

2016-11-01

Numerical experiments involving street canyons of varying aspect ratio with traffic-induced pollutants (PM 2.5 ) and implanted trees of varying aspect ratio, leaf area index, leaf area density distribution, trunk height, tree-covered area, and tree planting pattern under different wind conditions were conducted using a computational fluid dynamics (CFD) model, ENVI-met. Various aspects of dispersion and deposition were investigated, which include the influence of various tree configurations and wind condition on dispersion within the street canyon, pollutant mass at the free stream layer and street canyon, and comparison between mass removal by surface (leaf) deposition and mass enhancement due to the presence of trees. Results revealed that concentration level was enhanced especially within pedestrian level in street canyons with trees relative to their tree-free counterparts. Additionally, we found a dependence of the magnitude of concentration increase (within pedestrian level) and decrease (above pedestrian level) due to tree configuration and wind condition. Furthermore, we realized that only ∼0.1-3 % of PM 2.5 was dispersed to the free stream layer while a larger percentage (∼97 %) remained in the canyon, regardless of its aspect ratio, prevailing wind condition, and either tree-free or with tree (of various configuration). Lastly, results indicate that pollutant removal due to deposition on leaf surfaces is potentially sufficient to counterbalance the enhancement of PM 2.5 by such trees under some tree planting scenarios and wind conditions.

The study of atmospheric dispersion of radionuclide near nuclear power plant using CFD approach

International Nuclear Information System (INIS)

Nagrale, Dhanesh B.; Bera, Subrata; Deo, Anuj K.; Gaikwad, Avinash J.

2015-01-01

Most of the studies on atmospheric dispersion of radioactive material released from nuclear power plants are based on Gaussian plume models which fail to take account turbulence generated. The Fire Dynamic Simulator (FDS) code is one such flow model that uses a form of Navier-Stokes equation for low mach number applications. In the 0-2 km range near nuclear power plant, mainly near the source of emission of radionuclides, obstructions like natural draft cooling towers, plant building and structures are located. The stability class 'F' conditions and temperature of surrounding atmosphere, 15°C are considered in analysis. Main constituents of radionuclides released from stack mainly xenon, krypton. Two cases are carried out a) dispersion of gases without obstruction of cooling tower and b) dispersion of gases with obstruction of cooling tower. It is observed that mass fraction of radionuclides near the cooling tower ground increased to certain extent due to obstruction and wake effect. (author)

Simulation of wind-driven dispersion of fire pollutants in a street canyon using FDS.

Science.gov (United States)

Pesic, Dusica J; Blagojevic, Milan Dj; Zivkovic, Nenad V

2014-01-01

Air quality in urban areas attracts great attention due to increasing pollutant emissions and their negative effects on human health and environment. Numerous studies, such as those by Mouilleau and Champassith (J Loss Prevent Proc 22(3): 316-323, 2009), Xie et al. (J Hydrodyn 21(1): 108-117, 2009), and Yassin (Environ Sci Pollut Res 20(6): 3975-3988, 2013) focus on the air pollutant dispersion with no buoyancy effect or weak buoyancy effect. A few studies, such as those by Hu et al. (J Hazard Mater 166(1): 394-406, 2009; J Hazard Mater 192(3): 940-948, 2011; J Civ Eng Manag (2013)) focus on the fire-induced dispersion of pollutants with heat buoyancy release rate in the range from 0.5 to 20 MW. However, the air pollution source might very often be concentrated and intensive, as a consequence of the hazardous materials fire. Namely, transportation of fuel through urban areas occurs regularly, because it is often impossible to find alternative supply routes. It is accompanied with the risk of fire accident occurrences. Accident prevention strategies require analysis of the worst scenarios in which fire products jeopardize the exposed population and environment. The aim of this article is to analyze the impact of wind flow on air pollution and human vulnerability to fire products in a street canyon. For simulation of the gasoline tanker truck fire as a result of a multivehicle accident, computational fluid dynamics large eddy simulation method has been used. Numerical results show that the fire products flow vertically upward, without touching the walls of the buildings in the absence of wind. However, when the wind velocity reaches the critical value, the products touch the walls of the buildings on both sides of the street canyon. The concentrations of carbon monoxide and soot decrease, whereas carbon dioxide concentration increases with the rise of height above the street canyon ground level. The longitudinal concentration of the pollutants inside the street

Assessing the air quality impact of nitrogen oxides and benzene from road traffic and domestic heating and the associated cancer risk in an urban area of Verona (Italy)

Science.gov (United States)

Schiavon, Marco; Redivo, Martina; Antonacci, Gianluca; Rada, Elena Cristina; Ragazzi, Marco; Zardi, Dino; Giovannini, Lorenzo

2015-11-01

Simulations of emission and dispersion of nitrogen oxides (NOx) are performed in an urban area of Verona (Italy), characterized by street canyons and typical sources of urban pollutants. Two dominant source categories are considered: road traffic and, as an element of novelty, domestic heaters. Also, to assess the impact of urban air pollution on human health and, in particular, the cancer risk, simulations of emission and dispersion of benzene are carried out. Emissions from road traffic are estimated by the COPERT 4 algorithm, whilst NOx emission factors from domestic heaters are retrieved by means of criteria provided in the technical literature. Then maps of the annual mean concentrations of NOx and benzene are calculated using the AUSTAL2000 dispersion model, considering both scenarios representing the current situation, and scenarios simulating the introduction of environmental strategies for air pollution mitigation. The simulations highlight potentially critical situations of human exposure that may not be detected by the conventional network of air quality monitoring stations. The proposed methodology provides a support for air quality policies, such as planning targeted measurement campaigns, re-locating monitoring stations and adopting measures in favour of better air quality in urban planning. In particular, the estimation of the induced cancer risk is an important starting point to conduct zoning analyses and to detect the areas where population is more directly exposed to potential risks for health.

Analysis of Nonlinear Dispersion of a Pollutant Ejected by an External Source into a Channel Flow

Directory of Open Access Journals (Sweden)

T. Chinyoka

2010-01-01

Full Text Available This paper focuses on the transient analysis of nonlinear dispersion of a pollutant ejected by an external source into a laminar flow of an incompressible fluid in a channel. The influence of density variation with pollutant concentration is approximated according to the Boussinesq approximation, and the nonlinear governing equations of momentum and pollutant concentration are obtained. The problem is solved numerically using a semi-implicit finite difference method. Solutions are presented in graphical form and given in terms of fluid velocity, pollutant concentration, skin friction, and wall mass transfer rate for various parametric values. The model can be a useful tool for understanding the polluting situations of an improper discharge incident and evaluating the effects of decontaminating measures for the water body.

Transport and dispersion of pollutants in surface impoundments: a finite element model

International Nuclear Information System (INIS)

Yeh, G.T.

1980-07-01

A surface impoundment model in finite element (SIMFE) is presented to enable the simulation of flow circulations and pollutant transport and dispersion in natural or artificial lakes, reservoirs or ponds with any number of islands. This surface impoundment model consists of two sub-models: hydrodynamic and pollutant transport models. Both submodels are simulated by the finite element method. While the hydrodynamic model is solved by the standard Galerkin finite element scheme, the pollutant transport model can be solved by any of the twelve optional finite element schemes built in the program. Theoretical approximations and the numerical algorithm of SIMFE are described. Detail instruction of the application are given and listing of FORTRAN IV source program are provided. Two sample problems are given. One is for an idealized system with a known solution to show the accuracy and partial validation of the models. The other is applied to Prairie Island for a set of hypothetical input data, typifying a class of problems to which SIMFE may be applied

Transport and dispersion of pollutants in surface impoundments: a finite element model

Energy Technology Data Exchange (ETDEWEB)

Yeh, G.T.

1980-07-01

A surface impoundment model in finite element (SIMFE) is presented to enable the simulation of flow circulations and pollutant transport and dispersion in natural or artificial lakes, reservoirs or ponds with any number of islands. This surface impoundment model consists of two sub-models: hydrodynamic and pollutant transport models. Both submodels are simulated by the finite element method. While the hydrodynamic model is solved by the standard Galerkin finite element scheme, the pollutant transport model can be solved by any of the twelve optional finite element schemes built in the program. Theoretical approximations and the numerical algorithm of SIMFE are described. Detail instruction of the application are given and listing of FORTRAN IV source program are provided. Two sample problems are given. One is for an idealized system with a known solution to show the accuracy and partial validation of the models. The other is applied to Prairie Island for a set of hypothetical input data, typifying a class of problems to which SIMFE may be applied.

Assessment, analysis and appraisal of road traffic noise pollution in Rourkela city, India.

Science.gov (United States)

Goswami, Shreerup; Swain, Bijay Kumar; Panda, Santosh Kumar

2013-09-01

The problem of road traffic noise pollution has become a concern for both the public and the policy makers. Noise level was assessed in 12 different squares of Rourkela city during different specified times (7-10 a.m., 11 a.m.-2 p.m., 3-6 p.m., 7-10 p.m., 10 p.m.-12 midnight and 4-6 a.m.). Noise descriptors such as L,eq, traffic noise index, noise pollution level, noise climate, Lday, Levening, Lnight and Lden were assessed to reveal the extent of noise pollution due to heavy traffic in this city. The equivalent noise levels of all the 12 squares were found to be much beyond the permissible limit (70dB during day time and 55dB during night time). Appallingly, even the minimum L eq and NPL values were more than 82 dB and 96 dB during day time and 69 dB and 91 dB during night time respectively. Lden values of investigated squares ranged from 83.4 to 86.1 dB and were even more than the day time permissible limit of traffic noise. The prediction model was used in the present study to predict noise pollution level instead of Leq. Comparison of predicted with that of the actual measured data demonstrated that the model used for the prediction has the ability to calibrate the multicomponent traffic noise and yield reliable results close to that by direct measurement. Lastly, it is inferred that the dimension of the traffic generated noise pollution in Rourkela is critical.

Towards an agent based traffic regulation and recommendation system for the on-road air quality control

OpenAIRE

Sadiq, Abderrahmane; El Fazziki, Abdelaziz; Ouarzazi, Jamal; Sadgal, Mohamed

2016-01-01

This paper presents an integrated and adaptive problem-solving approach to control the on-road air quality by modeling the road infrastructure, managing traffic based on pollution level and generating recommendations for road users. The aim is to reduce vehicle emissions in the most polluted road segments and optimizing the pollution levels. For this we propose the use of historical and real time pollution records and contextual data to calculate the air quality index on road networks and gen...

EnviroAtlas - Woodbine, IA - Near Road Tree Buffer

Data.gov (United States)

U.S. Environmental Protection Agency — This EnviroAtlas dataset addresses the tree buffer along heavily traveled roads. The roads are interstates, arterials, and collectors within the EnviroAtlas...

EnviroAtlas - Phoenix, AZ - Near Road Tree Buffer

Data.gov (United States)

U.S. Environmental Protection Agency — This EnviroAtlas dataset addresses the tree buffer along heavily traveled roads. The roads are interstates, arterials, and collectors within the EnviroAtlas...

EnviroAtlas - Tampa, FL - Near Road Tree Buffer

Data.gov (United States)

U.S. Environmental Protection Agency — This EnviroAtlas dataset addresses the tree buffer along heavily traveled roads. The roads are interstates, arterials, and collectors within the EnviroAtlas...

EnviroAtlas - Durham, NC - Near Road Tree Buffer

Data.gov (United States)

U.S. Environmental Protection Agency — This EnviroAtlas dataset addresses the tree buffer along heavily traveled roads. The roads are interstates, arterials, and collectors within the EnviroAtlas...

EnviroAtlas - Austin, TX - Near Road Tree Buffer

Data.gov (United States)

U.S. Environmental Protection Agency — This EnviroAtlas dataset addresses the tree buffer along heavily traveled roads. The roads are interstates, arterials, and collectors within the EnviroAtlas...

EnviroAtlas - Paterson, NJ - Near Road Tree Buffer

Data.gov (United States)

U.S. Environmental Protection Agency — This EnviroAtlas dataset addresses the tree buffer along heavily traveled roads. The roads are interstates, arterials, and collectors within the EnviroAtlas...

EnviroAtlas - Portland, ME - Near Road Tree Buffer

Data.gov (United States)

U.S. Environmental Protection Agency — This EnviroAtlas dataset addresses the tree buffer along heavily traveled roads. The roads are interstates, arterials, and collectors within the EnviroAtlas...

EnviroAtlas - Portland, OR - Near Road Tree Buffer

Data.gov (United States)

U.S. Environmental Protection Agency — This EnviroAtlas dataset addresses the tree buffer along heavily traveled roads. The roads are interstates, arterials, and collectors within the EnviroAtlas...

EnviroAtlas - Cleveland, OH - Near Road Tree Buffer

Data.gov (United States)

U.S. Environmental Protection Agency — This EnviroAtlas dataset addresses the tree buffer along heavily traveled roads. The roads are interstates, arterials, and collectors within the EnviroAtlas...

EnviroAtlas - Memphis, TN - Near Road Tree Buffer

Data.gov (United States)

U.S. Environmental Protection Agency — This EnviroAtlas dataset addresses the tree buffer along heavily traveled roads. The roads are interstates, arterials, and collectors within the EnviroAtlas...

EnviroAtlas - Fresno, CA - Near Road Tree Buffer

Data.gov (United States)

U.S. Environmental Protection Agency — This EnviroAtlas dataset addresses the tree buffer along heavily traveled roads. The roads are interstates, arterials, and collectors within the EnviroAtlas...

EnviroAtlas - Pittsburgh, PA - Near Road Tree Buffer

Data.gov (United States)

U.S. Environmental Protection Agency — This EnviroAtlas dataset addresses the tree buffer along heavily traveled roads. The roads are interstates, arterials, and collectors within the EnviroAtlas...

Experimental study on thermal dispersion in and near the surf zone

International Nuclear Information System (INIS)

Komori, Shuzo; Tanaka, Hiroyoshi; Wada, Akira

1978-01-01

The site of Fukushima No. 1 Nuclear Power Station of Tokyo Electric Power Company was selected, and first, irregular waves with the typical wave spectra (in usual time and in storm time) in the sea region of the site were reproduced in the hydraulic model, then the characteristics of thermal dispersion and the velocityfield of warmed water (its discharge is 25.3 m 3 /sec.) in and near the surf zone under the action of those irregular waves were discussed. Finally, the similarity was investigated between the dispersion phenomenon in the hydraulic model and that in the prototype by comparing the experimental results of the dispersion range of warmed water with the results of field measurements. It may be concluded that the enveloped range of thermal dispersion in prototype can be predicted fairly correctly under almost the same discharge condition as this experiment if the prototype conditions of waves and currents are considered carefully and reproduced in a hydraulic model. (Kobatake, H.)

Polaritons dispersion in a composite ferrite-semiconductor structure near gyrotropic-nihility state

Energy Technology Data Exchange (ETDEWEB)

Tuz, Vladimir R., E-mail: tvr@rian.kharkov.ua

2016-12-01

In the context of polaritons in a ferrite-semiconductor structure which is influenced by an external static magnetic field, the gyrotropic-nihility can be identified from the dispersion equation related to bulk polaritons as a particular extreme state, at which the longitudinal component of the corresponding constitutive tensor and bulk constant simultaneously acquire zero. Near the frequency of the gyrotropic-nihility state, the conditions of branches merging of bulk polaritons, as well as an anomalous dispersion of bulk and surface polaritons are found and discussed. - Highlights: • Gyrotropic-nihility state is identified from the dispersion equation related to bulk polaritons in a magnetic-semiconductor superlattice. • The conditions of branches merging of bulk polaritons are found. • An anomalous dispersion of bulk and surface polaritons is found and discussed.

Polaritons dispersion in a composite ferrite-semiconductor structure near gyrotropic-nihility state

International Nuclear Information System (INIS)

Tuz, Vladimir R.

2016-01-01

In the context of polaritons in a ferrite-semiconductor structure which is influenced by an external static magnetic field, the gyrotropic-nihility can be identified from the dispersion equation related to bulk polaritons as a particular extreme state, at which the longitudinal component of the corresponding constitutive tensor and bulk constant simultaneously acquire zero. Near the frequency of the gyrotropic-nihility state, the conditions of branches merging of bulk polaritons, as well as an anomalous dispersion of bulk and surface polaritons are found and discussed. - Highlights: • Gyrotropic-nihility state is identified from the dispersion equation related to bulk polaritons in a magnetic-semiconductor superlattice. • The conditions of branches merging of bulk polaritons are found. • An anomalous dispersion of bulk and surface polaritons is found and discussed.

The ecological risk, source identification, and pollution assessment of heavy metals in road dust: a case study in Rafsanjan, SE Iran.

Science.gov (United States)

Mirzaei Aminiyan, Milad; Baalousha, Mohammed; Mousavi, Rouhollah; Mirzaei Aminiyan, Farzad; Hosseini, Hamideh; Heydariyan, Amin

2018-05-01

Heavy metal (HM) contamination in road dust is a potential environmental and human health threat. The sources, concentrations, spatial distribution, and ecological risk of As, Cd, Cu, Cr, Ni, Pb, and Zn in road dust in Rafsanjan City, Iran, were investigated. Pollution was assessed using the enrichment factor (EF). The potentially harmful effects of HMs were evaluated by calculating the potential ecological risk factor of individual metals (E r ) and of multiple metals (RI) using the Hakanson method. Correlation and principal component analyses (PCA) were applied to identify HM pollution sources. The concentrations of HMs in road dust were higher (ca. 5-10 folds) than their natural background values. The EF and E r increased according to the following order Cu > Pb > As > Zn > Cd > Cr > Ni and Cu > Cd > Pb > As > Ni > Zn > Cr, respectively. Thus, Cu is regarded as the pollutant of highest concern. Based on potential ecological risk index (RI) spatial distribution, all parts of Rafsanjan are characterized by significantly high potential ecological risk. HM concentration heat maps, PCA, and correlation analysis suggest that Cu, Pb, As, Cd, and Zn may have originated from the same source and follow the same spatial distribution pattern. These metals originated mainly from anthropogenic sources like copper mining and smelting plants, industrial and chemical activities, inordinate application of chemical fertilizers and pesticides in farmlands, and heavy traffic. Ni and Cr are likely to origniate from the industrial activities and traffic load in Rafsanjan City.

Runoff and windblown vehicle spray from road surfaces, risks and measures for soil and water.

NARCIS (Netherlands)

Schipper, P.N.M.; Comans, R.N.J.; Dijkstra, J.J.; Vergouwen, L.

2007-01-01

Soil and surface water along roads are exposed to pollution from motorways. The main pollutants are polycyclic aromatic hydrocarbons (PAH), mineral oil, heavy metals and salt. These pollutants originate from vehicles (fuel, wires, leakage), wear and degradation of road surfaces and road furniture

THE INFLUENCE OF BUOYANCY ON FLOW AND POLLUTANT DISPERSION IN STREET CANYONS

OpenAIRE

Buccolieri, Riccardo; Pulvirenti, Beatrice; Di Sabatino, Silvana; Britter, Rex

2008-01-01

Abstract: In this paper, the effect of buoyancy on flow and pollutant dispersion within street canyons is studied by means of computational fluid dynamics simulations. We consider a neutral boundary layer approaching a 3D street canyon assuming a wind direction perpendicular to the street canyon. The Boussinesq hypothesis for incompressible fluids is chosen for modelling buoyancy. We distinguish three cases: leeward, ground and windward wall heating. Thermal effects on both the flow ...

Performance assessment of Large Eddy Simulation (LES) for modeling dispersion in an urban street canyon with tree planting

NARCIS (Netherlands)

Moonen, P.; Gromke, C.B.; Dorer, V.

2013-01-01

The potential of a Large Eddy Simulation (LES) model to reliably predict near-field pollutant dispersion is assessed. To that extent, detailed time-resolved numerical simulations of coupled flow and dispersion are conducted for a street canyon with tree planting. Different crown porosities are

Subsurface soil and water pollution by diesel fuel at Bozdarevac railway station near Belgrade and remedial measures

International Nuclear Information System (INIS)

Vujasinovic, S.; Matic, D.I.

1991-01-01

An excessive pollution of ground water and the hydrogeologic environment by naphtha and its derivatives spilled on the surface has been recorded in Yugoslavia. The similar accidents in Serbia (Obrenovac, Uzicka Pozega, Beograd-Makis, Beograd-Danube railway station, Leskovac, Bozdarevac, etc.) have increased in number in the last several years. Transportation of naphtha and its derivatives, either by road or river, from the refineries to the consumers is obviously contributing much to the environmental pollution hazard. For the wide range of use and the specific effect on ground water, this pollutant can be taken for one of the first order. This paper discusses a case example. (Author)

Environmental exposure of road borders to zinc

Energy Technology Data Exchange (ETDEWEB)

Blok, J. [Royal Haskoning, P.O. Box 151, 6500 Ad Nijmegen (Netherlands)]. E-mail: Han.Blok@royalhaskoning.com

2005-09-15

The emissions of zinc along roads originating from tyre wear, corrosion of safety fence and other traffic-related sources have been quantified and validated by measured long-term loads in road run-off and airborne solids (drift) for 29 published case studies. The distribution pattern over the road border at various distances from the edge of the paved surface is assessed on the basis of 38 published case studies with measured concentrations in soil. For the impact assessment, the road border is differentiated into a zone that is part of the 'technosphere' and the 'target zone' beyond that technosphere that can be considered as part of the receiving environment. The 'technosphere' of the road includes the central reservation, the hard and the soft shoulder or, if one or both shoulders are not present, the so-called obstacle 'free zone' that is defined by road engineers. Pollution within the technosphere may require appropriate management of solid disposal and isolation from groundwater to prevent further distribution of pollutants to the environment. In the target zone along regional roads, the zinc load is about 4 mg/m{sup 2} year and this is of the same order of magnitude as that of atmospheric deposition in areas beyond the influence of roads (background). In the target zone along highways, the zinc load is increased in comparison to the background deposition. The average load of about 38 mg/m{sup 2} year is similar to that in fertilised agricultural land. Because most of the emitted zinc stays in the technosphere, the total amount entering this target zone along highways is limited. From the 140 tons of zinc per year that is released from tyre wear in The Netherlands, 64 tons is emitted in the urban area, 6.5 tons reaches to the target zones of all roads and only 1.1 tons of zinc will enter the target zone along highways. This amount will be further decreased by the application of porous asphalt in the near future. The

Roadside vegetation design characteristics that can improve local, near road air quality

Science.gov (United States)

As public health concerns have increased due to the rising number of studies linking adverse health effects with exposures to traffic-related pollution near large roadways, interest in methods to mitigate these exposures have also increased. Several studies have investigated the...

Calculation of Longitudinal Dispersion Coefficient and Modeling the Pollution Transmission in Rivers (Case studies: Severn and Narew Rivers

Directory of Open Access Journals (Sweden)

A. Parsaie

2017-01-01

Full Text Available Introduction: The study of rivers’ water quality is extremely important. This issue is more important when the rivers are one of the main sources of water supply for drinking, agriculture and industry. Unfortunately, river pollution has become one of the most important problems in the environment. When a source of pollution is transfused into the river, due to molecular motion, turbulence, and non-uniform velocity in cross-section of flow, it quickly spreads and covers all around the cross section and moves along the river with the flow. The governing equation of pollutant transmission in river is Advection Dispersion Equation (ADE. Computer simulation of pollution transmission in rives needs to solve the ADE by analytical or numerical approaches. The ADE has analytical solution under simple boundary and initial conditions but when the flow geometry and hydraulic conditions becomes more complex such as practical engineering problems, the analytical solutions are not applicable. Therefore, to solve this equation several numerical methods have been proposed. In this paper by getting the pollution transmission in the Severn River and Narew River was simulated. Materials and Methods: The longitudinal dispersion coefficient is proportional of properties of Fluid, hydraulic condition and the river geometry characteristics. For fluid properties the density and dynamic viscosity and for hydraulic condition, the velocity, flow depth, velocity and energy gradient slope and for river geometry the width of cross section and longitudinal slope can be mentioned. Several other parameters are influencive, but cannot be clearly measured such as sinuosity path and bed form of river. To derive the governed equation of pollution transmission in river, it is enough to consider an element of river and by using the continuity equation and Fick laws to balancing the inputs and outputs the pollution discharge. To calculate the dispersion coefficient several ways as

Vertebrate Ticks Distribution and Their Role as Vectors in Relation to Road Edges and Underpasses.

Science.gov (United States)

Delgado, Juan D; Abreu-Yanes, Estefanía; Abreu-Acosta, Néstor; Flor, Manuel D; Foronda, Pilar

2017-06-01

Roads fragment vertebrate populations and affect the dynamics and dispersal patterns of vertebrate parasites. We evaluated how vertebrate ticks distribute near roads and road underpasses in human-caused road-fragmented landscapes in Seville, SW Spain. We sampled 49 stations with 93 individualized sampling points and assessed tick abundance. We explored the relationship between tick presence and abundance and distance to the nearest road and underpass (drainage culverts and other passages used by vertebrates), and landscape features through categorical regression and nonparametric statistics. The presence of the tick-borne pathogens Borrelia sp. and Bartonella sp. was also analyzed by PCR. We found preliminary evidence of high relative tick abundance next to roads and in the vicinity of road underpasses. Plant cover type was related to tick presence in this road context. Implications of road permeability and edge effect in patterns of vertebrate-tick relationships in road fragmentation contexts are discussed. Both Borrelia sp. and Bartonella sp. were detected in the ticks analyzed. This is the first report of these bacteria in ticks from Seville. The results confirm the potential risk of acquiring Lyme disease and bartonellosis in this area.

Effects of urban and motor vehicle pollution on plants: State of art

International Nuclear Information System (INIS)

Bussotti, F.

1995-01-01

Motor vehicle pollution is a very important fraction of overall pollution: urban areas and those near road ways are the most exposed. In these zones the vegetation is already growing in difficult conditions to begin with and the additional pollution stress further reduces the plants' vitality, as well as presenting specific management problems. This paper examines the international scientific literature dealing with the effects of motor vehicle pollution on plants. The main effects are: accumulation of heavy metals, sulphur and nitrogen; deposition of particles on leaf surfaces; effect of pollutants on leaf surfaces, on photosynthesis, on transpiration, on leaf anatomy and on growth processes. Lastly, the paper examines the interaction between the various kinds of stressors

Micro-meteorological modelling in urban areas: pollutant dispersion and radiative effects modelling

International Nuclear Information System (INIS)

Milliez, Maya

2006-01-01

Atmospheric pollution and urban climate studies require to take into account the complex processes due to heterogeneity of urban areas and the interaction with the buildings. In order to estimate the impact of buildings on flow and pollutant dispersion, detailed numerical simulations were performed over an idealized urban area, with the three-dimensional model Mercure-Saturne, modelling both concentration means and their fluctuations. To take into account atmospheric radiation in built up areas and the thermal effects of the buildings, we implemented a three-dimensional radiative model adapted to complex geometry. This model, adapted from a scheme used for thermal radiation, solves the radiative transfer equation in a semi-transparent media, using the discrete ordinate method. The new scheme was validated with idealized cases and compared to a complete case. (author) [fr

Methodology for estimation of secondary meteorological variables to be used in local dispersion of air pollutants

International Nuclear Information System (INIS)

Turtos, L.; Sanchez, M.; Roque, A.; Soltura, R.

2003-01-01

Methodology for estimation of secondary meteorological variables to be used in local dispersion of air pollutants. This paper include the main works, carried out into the frame of the project Atmospheric environmental externalities of the electricity generation in Cuba, aiming to develop methodologies and corresponding software, which will allow to improve the quality of the secondary meteorological data used in atmospheric pollutant calculations; specifically the wind profiles coefficient, urban and rural mixed high and temperature gradients

Problems associated with the emissions limitations from road transport in the Lubuskie Province (Poland)

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Dzikuć, Maciej; Adamczyk, Janusz; Piwowar, Arkadiusz

2017-07-01

According to the report of the World Health Organization (WHO) on the list of 50 cities with the most polluted air in Europe as many as 33 are located in Poland. All the cities that are on the list exceed the maximum concentration of dust recommended by WHO at least three times. In the Lubuskie Province there is a very serious problem of maintaining good air quality. The air in Poland is among the most polluted in the European Union and this also applies to less-industrialized areas, such as Lubuskie, where the concentration levels of substances hazardous to human health and the environment are recorded as exceeded. One of the main factors affecting the poor air quality in the region is road transport. It is not just a problem near roads with heavy traffic, but also applies to the cities, where there is a large movement of cars, which are often old and do not meet current environmental standards. This article aims to identify the main sources of low emission from road transport and identify potential solutions to help reduce emission from this sector. The actions aimed at limiting low emission from road transport can bring a significant positive ecological effect. The aim of this article is to review one of the main sources of low emission in the province of Lubuskie, which is transportation. Moreover, the authors of the paper indicate the main problems associated with the emission coming from road transport and describe the possibilities for opportunities to reduce pollution from this sector. In addition, the article presents the three-scenario simulation of annual emissions from passenger cars that could take place in 2020.

Atmospheric aerosol dispersion models and their applications to environmental risk assessment

Directory of Open Access Journals (Sweden)

Andrzej Mazur

2014-03-01

Full Text Available Introduction. Numerical models of dispersion of atmospheric pollutants are widely used to forecast the spread of contaminants in the air and to analyze the effects of this phenomenon. The aim of the study is to investigate the possibilities and the quality of diagnosis and prediction of atmospheric transport of aerosols in the air using the dispersion model of atmospheric pollutants, developed at the Institute of Meteorology and Water Management (IMWM in Warsaw. Material and methods. A model of the dispersion of atmospheric pollutants, linked with meteorological models in a diagnostic mode, was used to simulate the transport of the cloud of aerosols released during the crash near the town of Ożydiw (Ukraine and of volcanic ash – during the volcanic eruption of Eyjafjallajökull in Iceland. Results. Possible directions of dispersion of pollutants in the air and its concentration in the atmosphere and deposition to the soil were assessed. The analysis of temporal variability of concentrations of aerosols in the atmosphere confirmed that the model developed at IMWM is an effective tool for diagnosis of air quality in the area of Poland as well as for determination of exposure duration to the aerosol clouds for different weather scenarios. Conclusions. The results are a confirmation of the thesis, that because in the environmental risk assessment, an important element is not only current information on the level of pollution concentrations, but also the time of exposure to pollution and forecast of these elements, and consequently the predicted effects on man or the environment in general; so it is necessary to use forecasting tools, similar to presented application. The dispersion model described in the paper is an operational tool for description, analysis and forecasting of emergency situations in case of emissions of hazardous substances.

Effects of building roof greening on air quality in street canyons

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Baik, Jong-Jin; Kwak, Kyung-Hwan; Park, Seung-Bu; Ryu, Young-Hee

2012-12-01

Building roof greening is a successful strategy for improving urban thermal environment. It is of theoretical interest and practical importance to study the effects of building roof greening on urban air quality in a systematic and quantitative way. In this study, we examine the effects of building roof greening on air quality in street canyons using a computational fluid dynamics (CFD) model that includes the thermodynamic energy equation and the transport equation of passive, non-reactive pollutants. For simplicity, building roof greening is represented by specified cooling. Results for a simple building configuration with a street canyon aspect ratio of one show that the cool air produced due to building roof greening flows into the street canyon, giving rise to strengthened street canyon flow. The strengthened street canyon flow enhances pollutant dispersion near the road, which decreases pollutant concentration there. Thus, building roof greening improves air quality near the road. The degree of air quality improvement near the road increases as the cooling intensity increases. In the middle region of the street canyon, the air quality can worsen when the cooling intensity is not too strong. Results for a real urban morphology also show that building roof greening improves air quality near roads. The degree of air quality improvement near roads due to building roof greening depends on the ambient wind direction. These findings provide a theoretical foundation for constructing green roofs for the purpose of improving air quality near roads or at a pedestrian level as well as urban thermal environment. Further studies using a CFD model coupled with a photochemistry model and a surface energy balance model are required to evaluate the effects of building roof greening on air quality in street canyons in a more realistic framework.

Legal regulations of restrictions of air pollution made by non-road mobile machinery-the case study for Europe: a review.

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Waluś, Konrad J; Warguła, Łukasz; Krawiec, Piotr; Adamiec, Jarosław M

2018-02-01

The high awareness of intensification and frequency of smog phenomenon all over the world in XXI age makes for detailed analyses of the reasons of its formation and prevention. The governments of the developed countries and conscious of real hazards, including many European countries, aim to restrict the emission of harmful gases. In literature, we can find the discussions on the influence of this phenomenon on the health and life of inhabitants of contaminated areas. Some elaborations of prognostic models, descriptions of pollution sources, the manner of their restriction, and the analysis of causal-consecutive correlation are also popular. The influence of pollutions resulting from the operation of vehicles, planes, and the industry are well described. However, every machine and device which is driven with a combustion engine has the effect on the general level of anthropogenic pollutions. These drives are subject of different regulations limiting their emission for service conditions and applications. One of the groups of such machines described in European and American regulations is non-road mobile machinery. The aim of this paper is the presentation of the problem of weak analysis and application of engineering and technological tools for machinery drive emission, despite of many publications on hazards and problems of emission. These machines have the influence on both the increase of global contamination and the machine users. The regulations of the European Union take into consideration the generated hazards and restrict the emission of machine exhaust gases by approval tests-these regulations are continually improved, and the effects of these works are new emission limits in 2019. However, these activities seem to be liberal as opposed to limits of the emission for passenger and goods vehicles where the technological development of the construction is greater and the regulations are the most rigorous. During the analysis of the development of non-road

Long-range transmission of pollutants simulated by a two-dimensional pseudospectral dispersion model

International Nuclear Information System (INIS)

Prahm, L.P.; Christensen, O.

1977-01-01

The pseudospectral dispersion model (Christensen and Prahm, 1976) is adapted for simulation of the long-range transmission of sulphur pollutants in the European region, covering an area of about 4000 km x 4000 km. Regional ''background'' concentrations of sulphur oxides are found to be highly dependent on distant sources and to correlate poorly with local source strength during the considered three- and four-day episodes. The simulation is based on emission data, given in squares of about 50 km x 50 km and on synoptic wind fields derived from observed wind velocities of the 850 mb level and the surface level. The two-dimensional model includes a constant vertical mixing depth. Appropriate values for the deposition and the transformation rates of SO 2 and SO/sup 4 are used. The concentration of pollutants computed from the two-dimensional pseudospectral dispersion model reflects the variable meteorological conditions. Computed concentrations are compared with measurements, giving spatial correlations between 0.4 and 0.8 for more than 400 ground-based 24 h mean values, and a spatial correlation of 0.9 for eight aircraft samples averaged over approx.30 min. A discussion of the influence of different sources of error in the model simulation is given. The high numerical accuracy of the pseudospectral model is combined with a modest consumption of CPU computer time. This study is the first application of the pseudospectral dispersion model which compares computed concentrations with measured field data. The model has possible applications as a tool for assessment of the impact of both national and international emission regulation strategies

Effects of pollution by oil and oil-dispersants on the common intertidal polychaetes, Cirriformia tentaculata and Cirratulus cirratus

Energy Technology Data Exchange (ETDEWEB)

George, J D

1971-08-01

An oil spill occurred from the Marine terminal of the Esso refinery at Fawley, England, where oil-polluted mudflats at the Hamble River mouth contained populations of Cirriformia tentaculata and Cirratulus cirratus. Quantitative studies on Cirriformia tentaculata and semi-quantitative studies of Cirratulus cirratus showed that spawning, growth, and mortality were unaffected by the oil. Reasons for the oil's ineffectiveness in disrupting life processes were discussed. On mudflats where Essolvene dispersant was used to remove oil from boats and shore installtions, number of both species decreased. Toxicity tests using Essolvene and BP 1002 showed that both species were killed by low concentrations of dispersant: C. cirratus was more tolerant, BP 1002 was most toxic. These populations showed recovery signs 2 yr after pollution. Tests showed a new dispersant, Corexit 7664, was less toxic than Essolvene and BP 1002, although all prevented gamete formation in C. cirratus at concentrations approaching the lethal level.

Inhalation of road dust by human subjects.

Science.gov (United States)

Takishima, T; Nakamura, M; Sasaki, M; Miyano, M; Yamaya, M; Sasaki, H

1987-11-01

We measured pneumomagnetic field strength (PMFS) in 42 healthy control subjects living in districts of Northern Japan with low levels of road dust pollution and in 39 healthy subjects living in areas with high levels of road dust pollution. Suspended road dust produced by studded tires increases from 30 micrograms/m3 during the summer season to levels as high as 400 micrograms/m3 during the snow season in the downtown areas of Sendai, Japan. Road dust retained in the lungs, containing 3% iron, was magnetized from the surface of the chest wall, and PMFS was measured. Three to 5 sequential PMFS measurements were made in each subject in March and October of 1984 and 1985, and in March 1986. The PMFS in control subjects in March 1984 was 37 +/- 14 pico-Tesla (mean +/- SD) and did not significantly differ from the PMFS in October 1984 or that in March 1985. In March 1984, the PMFS of the subjects in highly polluted areas was 95 +/- 100 pico-Tesla (mean +/- SD) and was significantly higher than that of control subjects (p less than 0.01) and subsequently decreased in March 1985 and in March 1986, corresponding to a decrease in suspended road dust brought about by a campaign to eliminate the use of studded tires. Our findings suggest that some road dust caused by studded tires is retained in the lungs.

Modelling and mapping trace element accumulation in Sphagnum peatlands at the European scale using a geomatic model of pollutant emissions dispersion.

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Diaz-de-Quijano, Maria; Joly, Daniel; Gilbert, Daniel; Toussaint, Marie-Laure; Franchi, Marielle; Fallot, Jean-Michel; Bernard, Nadine

2016-07-01

Trace elements (TEs) transported by atmospheric fluxes can negatively impact isolated ecosystems. Modelling based on moss-borne TE accumulation makes tracking TE deposition in remote areas without monitoring stations possible. Using a single moss species from ombrotrophic hummock peatlands reinforces estimate quality. This study used a validated geomatic model of particulate matter dispersion to identify the origin of Cd, Zn, Pb and Cu accumulated in Sphagnum capillifolium and the distance transported from their emission sources. The residential and industrial sectors of particulate matter emissions showed the highest correlations with the TEs accumulated in S. capillifolium (0.28(Zn)-0.56(Cu)) and (0.27(Zn)-0.47(Cu), respectively). Distances of dispersion varied depending on the sector of emissions and the considered TE. The greatest transportation distances for mean emissions values were found in the industrial (10.6 km when correlating with all TEs) and roads sectors (13 km when correlating with Pb). The residential sector showed the shortest distances (3.6 km when correlating with Cu, Cd, and Zn). The model presented here is a new tool for evaluating the efficacy of air pollution abatement policies in non-monitored areas and provides high-resolution (200 × 200 m) maps of TE accumulation that make it possible to survey the potential impacts of TEs on isolated ecosystems. Copyright © 2016 Elsevier Ltd. All rights reserved.

Invasive Brown Treesnake movements at road edges indicate road-crossing avoidance

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Siers, Shane R.; Savidge, Julie S; Reed, Robert N.

2014-01-01

Roads have significant impacts on the dispersal of wildlife. Although this poses a threat to the abundance and diversity of desirable flora and fauna, it also affords some opportunity for enhancing control of invasive species. Roads are the most common terrain features that may affect the rate of landscape-scale movements of invasive Brown Treesnakes (Boiga irregularis) throughout Guam. We radio tracked 45 free-ranging Brown Treesnakes in close proximity to two roads in Guam and recorded instances where daily relocations of snakes spanned roads. Then we reconstructed observed movement histories with randomized turning angles, which served as a useful null hypothesis for assessing the effect of roads or road edge habitat on Brown Treesnake movement patterns. Random walk simulations demonstrated that Brown Treesnakes crossed these roads at a rate far lower than would be expected if snake movement was random with respect to roads and road edge habitat. We discuss two alternative hypotheses for these results: 1) habitat gaps posed by roads physically or behaviorally restrict snake movement; or 2) road edges provide preferred foraging habitat from which snakes are reluctant to depart. Because roads often form the boundaries of jurisdictional and management units, the effects of roads on the movement of invasive Brown Treesnakes will influence the prospects for success of future landscape-level suppression efforts.

Finely Resolved On-Road PM2.5 and Estimated Premature Mortality in Central North Carolina.

Science.gov (United States)

Chang, Shih Ying; Vizuete, William; Serre, Marc; Vennam, Lakshmi Pradeepa; Omary, Mohammad; Isakov, Vlad; Breen, Michael; Arunachalam, Saravanan

2017-12-01

To quantify the on-road PM 2.5 -related premature mortality at a national scale, previous approaches to estimate concentrations at a 12-km × 12-km or larger grid cell resolution may not fully characterize concentration hotspots that occur near roadways and thus the areas of highest risk. Spatially resolved concentration estimates from on-road emissions to capture these hotspots may improve characterization of the associated risk, but are rarely used for estimating premature mortality. In this study, we compared the on-road PM 2.5 -related premature mortality in central North Carolina with two different concentration estimation approaches-(i) using the Community Multiscale Air Quality (CMAQ) model to model concentration at a coarser resolution of a 36-km × 36-km grid resolution, and (ii) using a hybrid of a Gaussian dispersion model, CMAQ, and a space-time interpolation technique to provide annual average PM 2.5 concentrations at a Census-block level (∼105,000 Census blocks). The hybrid modeling approach estimated 24% more on-road PM 2.5 -related premature mortality than CMAQ. The major difference is from the primary on-road PM 2.5 where the hybrid approach estimated 2.5 times more primary on-road PM 2.5 -related premature mortality than CMAQ due to predicted exposure hotspots near roadways that coincide with high population areas. The results show that 72% of primary on-road PM 2.5 premature mortality occurs within 1,000 m from roadways where 50% of the total population resides, highlighting the importance to characterize near-road primary PM 2.5 and suggesting that previous studies may have underestimated premature mortality due to PM 2.5 from traffic-related emissions. © 2017 Society for Risk Analysis.

Does Traffic-related Air Pollution Explain Associations of Aircraft and Road Traffic Noise Exposure on Children's Health and Cognition? A Secondary Analysis of the United Kingdom Sample From the RANCH Project

Science.gov (United States)

Clark, Charlotte; Crombie, Rosanna; Head, Jenny; van Kamp, Irene; van Kempen, Elise; Stansfeld, Stephen A.

2012-01-01

The authors examined whether air pollution at school (nitrogen dioxide) is associated with poorer child cognition and health and whether adjustment for air pollution explains or moderates previously observed associations between aircraft and road traffic noise at school and children's cognition in the 2001–2003 Road Traffic and Aircraft Noise Exposure and Children's Cognition and Health (RANCH) project. This secondary analysis of a subsample of the United Kingdom RANCH sample examined 719 children who were 9–10 years of age from 22 schools around London's Heathrow airport for whom air pollution data were available. Data were analyzed using multilevel modeling. Air pollution exposure levels at school were moderate, were not associated with a range of cognitive and health outcomes, and did not account for or moderate associations between noise exposure and cognition. Aircraft noise exposure at school was significantly associated with poorer recognition memory and conceptual recall memory after adjustment for nitrogen dioxide levels. Aircraft noise exposure was also associated with poorer reading comprehension and information recall memory after adjustment for nitrogen dioxide levels. Road traffic noise was not associated with cognition or health before or after adjustment for air pollution. Moderate levels of air pollution do not appear to confound associations of noise on cognition and health, but further studies of higher air pollution levels are needed. PMID:22842719

Does traffic-related air pollution explain associations of aircraft and road traffic noise exposure on children's health and cognition? A secondary analysis of the United Kingdom sample from the RANCH project.

Science.gov (United States)

Clark, Charlotte; Crombie, Rosanna; Head, Jenny; van Kamp, Irene; van Kempen, Elise; Stansfeld, Stephen A

2012-08-15

The authors examined whether air pollution at school (nitrogen dioxide) is associated with poorer child cognition and health and whether adjustment for air pollution explains or moderates previously observed associations between aircraft and road traffic noise at school and children's cognition in the 2001-2003 Road Traffic and Aircraft Noise Exposure and Children's Cognition and Health (RANCH) project. This secondary analysis of a subsample of the United Kingdom RANCH sample examined 719 children who were 9-10 years of age from 22 schools around London's Heathrow airport for whom air pollution data were available. Data were analyzed using multilevel modeling. Air pollution exposure levels at school were moderate, were not associated with a range of cognitive and health outcomes, and did not account for or moderate associations between noise exposure and cognition. Aircraft noise exposure at school was significantly associated with poorer recognition memory and conceptual recall memory after adjustment for nitrogen dioxide levels. Aircraft noise exposure was also associated with poorer reading comprehension and information recall memory after adjustment for nitrogen dioxide levels. Road traffic noise was not associated with cognition or health before or after adjustment for air pollution. Moderate levels of air pollution do not appear to confound associations of noise on cognition and health, but further studies of higher air pollution levels are needed.

Development and evaluation of SBLINE, a suite of models for the prediction of pollution concentrations from vehicles in urban areas

Energy Technology Data Exchange (ETDEWEB)

Namdeo, A.K.; Colls, J.J. [Environmental Science, University of Nottingham, Loughborough (United Kingdom)

1996-09-06

The assessment of air quality impacts from roadways is a major concern to urban planners, developers, health officials and engineers. This paper describes the development of a suite of models, called SBLINE, for prediction of pollution concentrations from vehicles in urban road networks. The first component of the suite is ROADFAC, an emission model for calculating emission rates for a road link with known vehicle fleet structure and operational details. ROADFAC can also calculate modal emission rates, caused by deceleration, idle, acceleration and cruise operational modes, by determining queue length and vehicle delay from traffic volume and signal phasing information. The other components of SBLINE are two dispersion models, called NOTLINE and CPB, for prediction of pollution concentrations contributed by different roadlinks in the network. These models use site geometry, meteorology, and traffic emissions calculated by ROADFAC to predict pollutant concentrations. The contribution from a given link is calculated by using NOTLINE if that link is situated in simple topography, or CPB is run if the link is inside a canyon or a cut-section. Finally, cumulative concentrations at any receptor location are calculated by adding the contributions from all roadlinks. SBLINE can be applied to any urban network of roads, with roadlinks located in either simple topography or street canyons. The program has been evaluated in one region of Leicester in the UK. The region represents a typical urban network of roads with some roads located in plain topography and some inside medium size canyons. Observed values of pollutant concentrations are compared with predictions made from detailed measurements of the vehicle population parameters, meteorology, and local street and building topography. Well-established statistical techniques have been used to show the potential of SBLINE for application to other road networks

Quantum treatment of field propagation in a fiber near the zero dispersion wavelength

Science.gov (United States)

Safaei, A.; Bassi, A.; Bolorizadeh, M. A.

2018-05-01

In this report, we present a quantum theory describing the propagation of the electromagnetic radiation in a fiber in the presence of the third order dispersion coefficient. We obtained the quantum photon-polariton field, hence, we provide herein a coupled set of operator forms for the corresponding nonlinear Schrödinger equations when the third order dispersion coefficient is included. Coupled stochastic nonlinear Schrödinger equations were obtained by applying a positive P-representation that governs the propagation and interaction of quantum solitons in the presence of the third-order dispersion term. Finally, to reduce the fluctuations near solitons in the first approximation, we developed coupled stochastic linear equations.

A CFD modeling study of the impacts of NO x and VOC emissions on reactive pollutant dispersion in and above a street canyon

Science.gov (United States)

Kwak, Kyung-Hwan; Baik, Jong-Jin

2012-01-01

A computational fluid dynamics (CFD) model that includes the carbon bond mechanism IV (CBM-IV) is developed and used to investigate reactive pollutant dispersion in and above a street canyon with an aspect ratio of 1. Fourteen emission scenarios of NO x and volatile organic compounds (VOCs) are considered. Dispersion types are classified into NO-type, NO 2-type, and O 3-type dispersion that exhibit concentration maxima at the street bottom, near the center of the street canyon, and above the street canyon, respectively. For the base emission scenario, the number of reactive species is 9 in the NO-type dispersion, 10 in the NO 2-type dispersion, and 15 in the O 3-type dispersion. As the NO x emission level decreases or the VOC emission level increases, some species in the O 3-type dispersion are shifted to the NO 2-type dispersion. The VOC-to-NO x emission ratio is found to be an important factor in determining the transition of dispersion type. In this transition process, OH plays a key role through a radical chain including HO 2, RO, and RO 2. Because of their high OH reactivities, XYL (xylene) and OLE (olefin carbon bond) among VOCs are largely responsible for the transition of dispersion type. The O 3 sensitivity is examined by reducing NO x or VOC emission level by a half. Because the NO titration of O 3 is more pronounced than the NO 2 photolysis and the radical chain process in the street canyon, the O 3 concentration therein is negatively correlated with the NO x emission level and weakly correlated with the VOC emission level. As a result, the street canyon is a negatively NO x-sensitive regime.

Downwind evolution of the volatility and mixing state of near-road aerosols near a US interstate highway

Science.gov (United States)

Saha, Provat K.; Khlystov, Andrey; Grieshop, Andrew P.

2018-02-01

We present spatial measurements of particle volatility and mixing state at a site near a North Carolina interstate highway (I-40) applying several heating (thermodenuder; TD) experimental approaches. Measurements were conducted in summer 2015 and winter 2016 in a roadside trailer (10 m from road edge) and during downwind transects at different distances from the highway under favorable wind conditions using a mobile platform. Results show that the relative abundance of semi-volatile species (SVOCs) in ultrafine particles decreases with downwind distance, which is consistent with the dilution and mixing of traffic-sourced particles with background air and evaporation of semi-volatile species during downwind transport. An evaporation kinetics model was used to derive particle volatility distributions by fitting TD data. While the TD-derived distribution apportions about 20-30 % of particle mass as semi-volatile (SVOCs; effective saturation concentration, C∗ ≥ 1µm-3) at 10 m from the road edge, approximately 10 % of particle mass is attributed to SVOCs at 220 m, showing that the particle-phase semi-volatile fraction decreases with downwind distance. The relative abundance of semi-volatile material in the particle phase increased during winter. Downwind spatial gradients of the less volatile particle fraction (that remaining after heating at 180 °C) were strongly correlated with black carbon (BC). BC size distribution and mixing state measured using a single-particle soot photometer (SP2) at the roadside trailer showed that a large fraction (70-80 %) of BC particles were externally mixed. Heating experiments with a volatility tandem differential mobility analyzer (V-TDMA) also showed that the nonvolatile fraction in roadside aerosols is mostly externally mixed. V-TDMA measurements at different distances downwind from the highway indicate that the mixing state of roadside aerosols does not change significantly (e.g., BC mostly remains externally mixed) within a

Aircraft noise, air pollution, and mortality from myocardial infarction.

Science.gov (United States)

Huss, Anke; Spoerri, Adrian; Egger, Matthias; Röösli, Martin

2010-11-01

Myocardial infarction has been associated with both transportation noise and air pollution. We examined residential exposure to aircraft noise and mortality from myocardial infarction, taking air pollution into account. We analyzed the Swiss National Cohort, which includes geocoded information on residence. Exposure to aircraft noise and air pollution was determined based on geospatial noise and air-pollution (PM10) models and distance to major roads. We used Cox proportional hazard models, with age as the timescale. We compared the risk of death across categories of A-weighted sound pressure levels (dB(A)) and by duration of living in exposed corridors, adjusting for PM10 levels, distance to major roads, sex, education, and socioeconomic position of the municipality. We analyzed 4.6 million persons older than 30 years who were followed from near the end of 2000 through December 2005, including 15,532 deaths from myocardial infarction (ICD-10 codes I 21, I 22). Mortality increased with increasing level and duration of aircraft noise. The adjusted hazard ratio comparing ≥60 dB(A) with noise. Aircraft noise was associated with mortality from myocardial infarction, with a dose-response relationship for level and duration of exposure. The association does not appear to be explained by exposure to particulate matter air pollution, education, or socioeconomic status of the municipality.

A numerical analysis of pollutant dispersion in street canyon: influence of the turbulent Schmidt number

Directory of Open Access Journals (Sweden)

Bouabdellah Abed

2017-12-01

Full Text Available Realizing the growing importance and availability of motor vehicles, we observe that the main source of pollution in the street canyons comes from the dispersion of automobile engine exhaust gas. It represents a substantial effect on the micro-climate conditions in urban areas. Seven idealized-2D building configurations are investigated by numerical simulations. The turbulent Schmidt number is introduced in the pollutant transport equation in order the take into account the proportion between the rate of momentum turbulent transport and the mass turbulent transport by diffusion. In the present paper, we attempt to approach the experimental test results by adjusting the values of turbulent Schmidt number to its corresponding application. It was with interest that we established this link for achieving our objectives, since the numerical results agree well with the experimental ones. The CFD code ANSYS CFX, the k, e and the RNGk-e models of turbulence have been adopted for the resolutions. From the simulation results, the turbulent Schmidt number is a range of 0.1 to 1.3 that has some effect on the prediction of pollutant dispersion in the street canyons. In the case of a flat roof canyon configuration (case: runa000, appropriate turbulent Schmidt number of 0.6 is estimated using the k-epsilon model and of 0.5 using the RNG k-e model.

Statistical modeling of road contribution as emission sources to total suspended particles (TSP) under MCF model downtown Medellin - Antioquia - Colombia, 2004

International Nuclear Information System (INIS)

Gomez, Miryam; Saldarriaga, Julio; Correa, Mauricio; Posada, Enrique; Castrillon M, Francisco Javier

2007-01-01

Sand fields, constructions, carbon boilers, roads, and biologic sources are air-contaminant-constituent factors in down town Valle de Aburra, among others. the distribution of road contribution data to total suspended particles according to the source receptor model MCF, source correlation modeling, is nearly a gamma distribution. Chi-square goodness of fit is used to model statistically. This test for goodness of fit also allows estimating the parameters of the distribution utilizing maximum likelihood method. As convergence criteria, the estimation maximization algorithm is used. The mean of road contribution data to total suspended particles according to the source receptor model MCF, is straightforward and validates the road contribution factor to the atmospheric pollution of the zone under study

Neighbourhood walkability, road density and socio-economic status in Sydney, Australia.

Science.gov (United States)

Cowie, Christine T; Ding, Ding; Rolfe, Margaret I; Mayne, Darren J; Jalaludin, Bin; Bauman, Adrian; Morgan, Geoffrey G

2016-04-27

Planning and transport agencies play a vital role in influencing the design of townscapes, travel modes and travel behaviors, which in turn impact on the walkability of neighbourhoods and residents' physical activity opportunities. Optimising neighbourhood walkability is desirable in built environments, however, the population health benefits of walkability may be offset by increased exposure to traffic related air pollution. This paper describes the spatial distribution of neighbourhood walkability and weighted road density, a marker for traffic related air pollution, in Sydney, Australia. As exposure to air pollution is related to socio-economic status in some cities, this paper also examines the spatial distribution of weighted road density and walkability by socio-economic status (SES). We calculated walkability, weighted road density (as a measure of traffic related air pollution) and SES, using predefined and validated measures, for 5858 Sydney neighbourhoods, representing 3.6 million population. We overlaid tertiles of walkability and weighted road density to define "sweet-spots" (high walkability-low weighted road density), and "sour- spots" (low walkability-high weighted road density) neighbourhoods. We also examined the distribution of walkability and weighted road density by SES quintiles. Walkability and weighted road density showed a clear east-west gradient across the region. Our study found that only 4 % of Sydney's population lived in sweet-spot" neighbourhoods with high walkability and low weighted road density (desirable), and these tended to be located closer to the city centre. A greater proportion of neighbourhoods had health limiting attributes of high weighted road density or low walkability (about 20 % each), and over 5 % of the population lived in "sour-spot" neighbourhoods with low walkability and high weighted road density (least desirable). These neighbourhoods were more distant from the city centre and scattered more widely. There were

Residential proximity to major roads and placenta/birth weight ratio.

Science.gov (United States)

Yorifuji, Takashi; Naruse, Hiroo; Kashima, Saori; Murakoshi, Takeshi; Tsuda, Toshihide; Doi, Hiroyuki; Kawachi, Ichiro

2012-01-01

Exposure to air pollution has been demonstrated to increase the risk of preterm birth and low birth weight. We examined whether proximity to major roads (as a marker of exposure to air pollution) is associated with increased placenta/birth weight ratio (as a biomarker of the placental transport function). Data on parental characteristics and birth outcomes were extracted from the database maintained by a major hospital in Shizuoka Prefecture, Japan. We restricted the analysis to mothers who delivered liveborn single births from 1997 to 2008 (n = 14,189). Using geocoded residential information, each birth was classified according to proximity to major roads. We examined the association between proximity to major roads and the placenta/birth weight ratio, using multiple linear regression. Proximity to major roads was associated with higher placenta/birth weight ratio. After adjusting for potential confounders, living within 200 m of a major road increased the ratio by 0.48% (95% CI = 0.15 to 0. 80). In addition, proximity to major roads was associated with lower placenta weight and birth weight. These observed associations were stronger among participants living closer to major roads. Exposure to traffic-related air pollution is associated with higher placenta/birth weight ratio. Impaired placental oxygen and nutrient transport function might be a mechanism for explaining the observed association between air pollution and low birth weight as well as preterm birth. Copyright © 2011 Elsevier B.V. All rights reserved.

Simulation of oil pollution in the Persian Gulf near Assaluyeh oil terminal

International Nuclear Information System (INIS)

Faghihifard, M.; Badri, M.A.

2016-01-01

Numerical simulation of oil slick movement with respect to tidal factors and wind effects was performed in order to counteract oil pollution in the Persian Gulf. First, a flow model was invoked with respect to water level fluctuations. The main tidal constituents were applied to the model using the initial conditions of water level variations in the Hormuz Strait near the Hangam Island. The movement of oil pollution was determined due to wind, tide and temperature effects and confirmed by applying a verified field results. Simulations were focused near an important terminal in the Persian Gulf, Assaluyeh Port. The results were led to preparing a risk-taking map in a parallel research for the Persian Gulf.

Mercury Pollution Near A Chlor-Alkali Plant In Northern Kazakhstan

Science.gov (United States)

In northern Kazakhstan, there is a serious case of mercury pollution near Pavlodar City from an old mercury cell chlor-alkali plant. The soil, sediment, and water is contaminated with more than a thousand tons of mercury and mercury compounds as a result of the operation of the ...

EnviroAtlas - Tampa, FL - Near Road Block Group Summary

Data.gov (United States)

U.S. Environmental Protection Agency — This EnviroAtlas dataset addresses the tree buffer along heavily traveled roads. The roads are interstates, arterials, and collectors within the EnviroAtlas...

EnviroAtlas - Austin, TX - Near Road Block Group Summary

Data.gov (United States)

U.S. Environmental Protection Agency — This EnviroAtlas dataset addresses the tree buffer along heavily traveled roads. The roads are interstates, arterials, and collectors within the EnviroAtlas...

EnviroAtlas - New York, NY - Near Road Tree Buffer

Data.gov (United States)

U.S. Environmental Protection Agency — This EnviroAtlas dataset addresses the tree buffer along heavily traveled roads. The roads are interstates, arterials, and collectors within the EnviroAtlas...

EnviroAtlas - Green Bay, WI - Near Road Tree Buffer

Data.gov (United States)

U.S. Environmental Protection Agency — This EnviroAtlas dataset addresses the tree buffer along heavily traveled roads. The roads are interstates, arterials, and collectors within the EnviroAtlas...

EnviroAtlas - Des Moines, IA - Near Road Tree Buffer

Data.gov (United States)

U.S. Environmental Protection Agency — This EnviroAtlas dataset addresses the tree buffer along heavily traveled roads. The roads are interstates, arterials, and collectors within the EnviroAtlas...

EnviroAtlas - Portland, OR - Near Road Block Group Summary

Data.gov (United States)

U.S. Environmental Protection Agency — This EnviroAtlas dataset addresses the tree buffer along heavily traveled roads. The roads are interstates, arterials, and collectors within the EnviroAtlas...

EnviroAtlas - Fresno, CA - Near Road Block Group Summary

Data.gov (United States)

U.S. Environmental Protection Agency — This EnviroAtlas dataset addresses the tree buffer along heavily traveled roads. The roads are interstates, arterials, and collectors within the EnviroAtlas...

EnviroAtlas - Woodbine, IA - Near Road Block Group Summary

Data.gov (United States)

U.S. Environmental Protection Agency — This EnviroAtlas dataset addresses the tree buffer along heavily traveled roads. The roads are interstates, arterials, and collectors within the EnviroAtlas...

EnviroAtlas - Portland, ME - Near Road Block Group Summary

Data.gov (United States)

U.S. Environmental Protection Agency — This EnviroAtlas dataset addresses the tree buffer along heavily traveled roads. The roads are interstates, arterials, and collectors within the EnviroAtlas...

EnviroAtlas - Memphis, TN - Near Road Block Group Summary

Data.gov (United States)

U.S. Environmental Protection Agency — This EnviroAtlas dataset addresses the tree buffer along heavily traveled roads. The roads are interstates, arterials, and collectors within the EnviroAtlas...

EnviroAtlas - Pittsburgh, PA - Near Road Block Group Summary

Data.gov (United States)

U.S. Environmental Protection Agency — This EnviroAtlas dataset addresses the tree buffer along heavily traveled roads. The roads are interstates, arterials, and collectors within the EnviroAtlas...

EnviroAtlas - Durham, NC - Near Road Block Group Summary

Data.gov (United States)

U.S. Environmental Protection Agency — This EnviroAtlas dataset addresses the tree buffer along heavily traveled roads. The roads are interstates, arterials, and collectors within the EnviroAtlas...

EnviroAtlas - New Bedford, MA - Near Road Tree Buffer

Data.gov (United States)

U.S. Environmental Protection Agency — This EnviroAtlas dataset addresses the tree buffer along heavily traveled roads. The roads are interstates, arterials, and collectors within the EnviroAtlas...

EnviroAtlas - Paterson, NJ - Near Road Block Group Summary

Data.gov (United States)

U.S. Environmental Protection Agency — This EnviroAtlas dataset addresses the tree buffer along heavily traveled roads. The roads are interstates, arterials, and collectors within the EnviroAtlas...

EnviroAtlas - Cleveland, OH - Near Road Block Group Summary

Data.gov (United States)

U.S. Environmental Protection Agency — This EnviroAtlas dataset addresses the tree buffer along heavily traveled roads. The roads are interstates, arterials, and collectors within the EnviroAtlas...

EnviroAtlas - Phoenix, AZ - Near Road Block Group Summary

Data.gov (United States)

U.S. Environmental Protection Agency — This EnviroAtlas dataset addresses the tree buffer along heavily traveled roads. The roads are interstates, arterials, and collectors within the EnviroAtlas...

Air pollutant dispersion from a large semi-enclosed stadium in an urban area: high-resolution CFD modeling versus full-scale measurements

NARCIS (Netherlands)

Hooff, van T.A.J.; Blocken, B.J.E.; Seppelt, R.; Voinov, A.A.; Lange, S.; Bankamp, D.

2012-01-01

Abstract: High-resolution CFD simulations and full-scale measurements have been performed to assess the dispersion of air pollutants (CO2) from the large semi-enclosed Amsterdam ArenA football stadium. The dispersion process is driven by natural ventilation by the urban wind flow and by buoyancy,

Are Chinese Green Transport Policies Effective? A New Perspective from Direct Pollution Rebound Effect, and Empirical Evidence From the Road Transport Sector

Directory of Open Access Journals (Sweden)

Lu-Yi Qiu

2017-03-01

Full Text Available Air pollution has become a serious challenge in China. Emissions from motor vehicles have been found to be one main sources of air pollution. Although the Chinese government has undertaken numerous green policies to mitigate harmful emissions from road transport sector, it is still uncertain for both policy makers and researchers to know whether the policies are effective in the short and long terms. We propose a new concept of “pollution rebound effect” (PRE to estimate the effectiveness of green traffic policies. We estimate direct air PRE as a measure of the effectiveness of the policies of reducing air pollution from the transport sector based on time-series data from the period 1986–2014. We find that the short-term direct air PRE is −0.4105, and the corresponding long-run PRE is −0.246. The negative results indicate that the direct air PRE does not exist in the road passenger transport sector in China, both in the short term and in the long term during the period 1986–2014. This implies that the Chinese green transport policies are effective in terms of harmful emissions reduction in the transport sector. This research, to the best of our knowledge, is the first attempt to quantify the effectiveness of the green transport policies in the transitional period that China is currently undergoing.

Near-road enhancement and solubility of fine and coarse particulate matter trace elements near a major interstate in Detroit, Michigan

Science.gov (United States)

Communities near major roadways are disproportionately affected by traffic-related air pollution which can contribute to adverse health outcomes. The specific role of particulate matter (PM) from traffic sources is not fully understood due to complex emissions processes and physi...

Seasonal Changing Effect on Airflow and Pollutant Dispersion Characteristics in Urban Street Canyons

OpenAIRE

Jingliang Dong; Zijing Tan; Yimin Xiao; Jiyuan Tu

2017-01-01

In this study, the effect of seasonal variation on air flow and pollutant dispersion characteristics was numerically investigated. A three-dimensional urban canopy model with unit aspect ratio (H/D = 1) was used to calculate surface temperature distribution in the street canyon. Four representative time events (1000 LST, 1300 LST, 1600 LST and 2000 LST) during typical clear summer and winter days were selected to examine the air flow diurnal variation. The results revealed the seasonal variat...

Road traffic noise, air pollution and incident cardiovascular disease: A joint analysis of the HUNT, EPIC-Oxford and UK Biobank cohorts.

Science.gov (United States)

Cai, Yutong; Hodgson, Susan; Blangiardo, Marta; Gulliver, John; Morley, David; Fecht, Daniela; Vienneau, Danielle; de Hoogh, Kees; Key, Tim; Hveem, Kristian; Elliott, Paul; Hansell, Anna L

2018-05-01

This study aimed to investigate the effects of long-term exposure to road traffic noise and air pollution on incident cardiovascular disease (CVD) in three large cohorts: HUNT, EPIC-Oxford and UK Biobank. In pooled complete-case sample of the three cohorts from Norway and the United Kingdom (N = 355,732), 21,081 incident all CVD cases including 5259 ischemic heart disease (IHD) and 2871 cerebrovascular cases were ascertained between baseline (1993-2010) and end of follow-up (2008-2013) through medical record linkage. Annual mean 24-hour weighted road traffic noise (Lden) and air pollution (particulate matter with aerodynamic diameter ≤ 10 μm [PM10], ≤2.5 μm [PM2.5] and nitrogen dioxide [NO2]) exposure at baseline address was modelled using a simplified version of the Common Noise Assessment Methods in Europe (CNOSSOS-EU) and European-wide Land Use Regression models. Individual-level covariate data were harmonised and physically pooled across the three cohorts. Analysis was via Cox proportional hazard model with mutual adjustments for both noise and air pollution and potential confounders. No significant associations were found between annual mean Lden and incident CVD, IHD or cerebrovascular disease in the overall population except that the association with incident IHD was significant among current-smokers. In the fully adjusted models including adjustment for Lden, an interquartile range (IQR) higher PM10 (4.1 μg/m3) or PM2.5 (1.4 μg/m3) was associated with a 5.8% (95%CI: 2.5%-9.3%) and 3.7% (95%CI: 0.2%-7.4%) higher risk for all incident CVD respectively. No significant associations were found between NO2 and any of the CVD outcomes. We found suggestive evidence of a possible association between road traffic noise and incident IHD, consistent with current literature. Long-term particulate air pollution exposure, even at concentrations below current European air quality standards, was significantly associated with incident CVD. Copyright �

Accumulation of Pb and Mn on Road Side Leaves, Analysis from Mauri Por to Hawks bay Road

International Nuclear Information System (INIS)

Salam, M.

2010-01-01

Accurate measurements of the heavy-metal contents in polluted areas are required to assess the potential ecological risks in these areas. Chemical and biological indicators are of interest when they provide information about the concentration and accumulation of heavy metals in the environment. These studies were conducted in order to investigate heavy-metal accumulation and the effect on Conocarpus (Conocarpus Erectus) on roadside trees. The total content of Pb and Mn was determined using atomic absorption spectrophotometry, AAS. The present results showed variations that indicate both the concerned species have the highest concentration in all the sampling areas near the road. According to the results present study, the average concentration of Pb and Mn are 10.576+3.482 micro g/gm and 91.977+ 30.030 micro g/gm respectively. The results showed that the plant demonstrated a physiological response to the heavy-metal pollution, which suggests that roadside plants are indicators of heavy-metal accumulation and the effect on the environment. (author)

Towards an agent based traffic regulation and recommendation system for the on-road air quality control.

Science.gov (United States)

Sadiq, Abderrahmane; El Fazziki, Abdelaziz; Ouarzazi, Jamal; Sadgal, Mohamed

2016-01-01

This paper presents an integrated and adaptive problem-solving approach to control the on-road air quality by modeling the road infrastructure, managing traffic based on pollution level and generating recommendations for road users. The aim is to reduce vehicle emissions in the most polluted road segments and optimizing the pollution levels. For this we propose the use of historical and real time pollution records and contextual data to calculate the air quality index on road networks and generate recommendations for reassigning traffic flow in order to improve the on-road air quality. The resulting air quality indexes are used in the system's traffic network generation, which the cartography is represented by a weighted graph. The weights evolve according to the pollution indexes and path properties and the graph is therefore dynamic. Furthermore, the systems use the available pollution data and meteorological records in order to predict the on-road pollutant levels by using an artificial neural network based prediction model. The proposed approach combines the benefits of multi-agent systems, Big data technology, machine learning tools and the available data sources. For the shortest path searching in the road network, we use the Dijkstra algorithm over Hadoop MapReduce framework. The use Hadoop framework in the data retrieve and analysis process has significantly improved the performance of the proposed system. Also, the agent technology allowed proposing a suitable solution in terms of robustness and agility.

Relative impact of on-road vehicular and point-source industrial emissions of air pollutants in a medium-sized Andean city

Science.gov (United States)

González, C. M.; Gómez, C. D.; Rojas, N. Y.; Acevedo, H.; Aristizábal, B. H.

2017-03-01

Cities in emerging countries are facing a fast growth and urbanization; however, the study of air pollutant emissions and its dynamics is scarce, making their populations vulnerable to potential effects of air pollution. This situation is critical in medium-sized urban areas built along the tropical Andean mountains. This work assesses the contribution of on-road vehicular and point-source industrial activities in the medium-sized Andean city of Manizales, Colombia. Annual fluxes of criteria pollutants, NMVOC, and greenhouse gases were estimated. Emissions were dominated by vehicular activity, with more than 90% of total estimated releases for the majority of air pollutants. On-road vehicular emissions for CO (43.4 Gg/yr) and NMVOC (9.6 Gg/yr) were mainly associated with the use of motorcycles (50% and 81% of total CO and NMVOC emissions respectively). Public transit buses were the main source of PM10 (47%) and NOx (48%). The per-capita emission index was significantly higher in Manizales than in other medium-sized cities, especially for NMVOC, CO, NOx and CO2. The unique mountainous terrain of Andean cities suggest that a methodology based on VSP model could give more realistic emission estimates, with additional model components that include slope and acceleration. Food and beverage facilities were the main contributors of point-source industrial emissions for PM10 (63%), SOx (55%) and NOx (45%), whereas scrap metal recycling had high emissions of CO (73%) and NMVOC (47%). Results provide the baseline for ongoing research in atmospheric modeling and urban air quality, in order to improve the understanding of air pollutant fluxes, transport and transformation in the atmosphere. In addition, this emission inventory could be used as a tool to identify areas of public health exposure and provide information for future decision makers.

An Analysis of Air Pollution in Makkah - a View Point of Source Identification

Directory of Open Access Journals (Sweden)

Turki M. Habeebullah

2013-07-01

Full Text Available Makkah is one of the busiest cities in Saudi Arabia and remains busy all year around, especially during the season of Hajj and the month of Ramadan when millions of people visit this city. This emphasizes the importance of clean air and of understanding the sources of various air pollutants, which is vital for the management and advanced modeling of air pollution. This study intends to identify the major sources of air pollutants in Makkah, near the Holy Mosque (Al-Haram using a graphical approach. Air pollutants considered in this study are nitrogen oxides (NOx, nitrogen dioxide (NO2, nitric oxide (NO, carbon monoxide (CO, sulphur dioxide (SO2, ozone (O3 and particulate matter with aero-dynamic diameter of 10 um or less (PM10. Polar plots, time variation plots and correlation analysis are used to analyse the data and identify the major sources of emissions. Most of the pollutants demonstrate high concentrations during the morning traffic peak hours, suggesting road traffic as the main source of emission. The main sources of pollutant emissions identified in Makkahwere road traffic, re-suspended and windblown dust and sand particles. Further investigation on detailedsource apportionment is required, which is part of the ongoing project.

Physical modelling of flow and dispersion over complex terrain

Science.gov (United States)

Cermak, J. E.

1984-09-01

Atmospheric motion and dispersion over topography characterized by irregular (or regular) hill-valley or mountain-valley distributions are strongly dependent upon three general sets of variables. These are variables that describe topographic geometry, synoptic-scale winds and surface-air temperature distributions. In addition, pollutant concentration distributions also depend upon location and physical characteristics of the pollutant source. Overall fluid-flow complexity and variability from site to site have stimulated the development and use of physical modelling for determination of flow and dispersion in many wind-engineering applications. Models with length scales as small as 1:12,000 have been placed in boundary-layer wind tunnels to study flows in which forced convection by synoptic winds is of primary significance. Flows driven primarily by forces arising from temperature differences (gravitational or free convection) have been investigated by small-scale physical models placed in an isolated space (gravitational convection chamber). Similarity criteria and facilities for both forced and gravitational-convection flow studies are discussed. Forced-convection modelling is illustrated by application to dispersion of air pollutants by unstable flow near a paper mill in the state of Maryland and by stable flow over Point Arguello, California. Gravitational-convection modelling is demonstrated by a study of drainage flow and pollutant transport from a proposed mining operation in the Rocky Mountains of Colorado. Other studies in which field data are available for comparison with model data are reviewed.

Study of lead pollution from automobile emissions in Khartoum

International Nuclear Information System (INIS)

Ibrahim, A.S.

2002-07-01

Aerosol and soil samples were collected from places near the main roads in Khartoum area. The samples were analyzed by energy Dispersive x-ray fluorescence (EDXRF) technique, to study the lead (Pb) concentration in air and soil near roadsides due to automobile emissions. The aim of the study was also to make a comparison with the results of previous measurements made in the same field (Ahmed, 1983) . Thee aerosol samples were taken from three sites in Khartoum area. Tuti island taken as a control area, central Khartoum as a commercial area and south of Khartoum as a residential area. Soil samples were taken from a place near Al Gurashi Park and another near Abu Hamama traffic junction in Khartoum area. The data obtained of (Pb) concentrations in the roadside air were statistically analyzed. Comparisons were made between the concentrations at the various times of the day and correlation were made with meteorological parameters. The (Pb) concentrations in the roadside soil were observed to be inversely proportional to the distance from the road and the depth from the layer of the earth. Finally, the results obtained are discussed and some recommendations are suggested. (Author)

Impact of trees on pollutant dispersion in street canyons: A numerical study of the annual average effects in Antwerp, Belgium.

Science.gov (United States)

Vranckx, Stijn; Vos, Peter; Maiheu, Bino; Janssen, Stijn

2015-11-01

Effects of vegetation on pollutant dispersion receive increased attention in attempts to reduce air pollutant concentration levels in the urban environment. In this study, we examine the influence of vegetation on the concentrations of traffic pollutants in urban street canyons using numerical simulations with the CFD code OpenFOAM. This CFD approach is validated against literature wind tunnel data of traffic pollutant dispersion in street canyons. The impact of trees is simulated for a variety of vegetation types and the full range of approaching wind directions at 15° interval. All these results are combined using meteo statistics, including effects of seasonal leaf loss, to determine the annual average effect of trees in street canyons. This analysis is performed for two pollutants, elemental carbon (EC) and PM10, using background concentrations and emission strengths for the city of Antwerp, Belgium. The results show that due to the presence of trees the annual average pollutant concentrations increase with about 8% (range of 1% to 13%) for EC and with about 1.4% (range of 0.2 to 2.6%) for PM10. The study indicates that this annual effect is considerably smaller than earlier estimates which are generally based on a specific set of governing conditions (1 wind direction, full leafed trees and peak hour traffic emissions). Copyright © 2015 Elsevier B.V. All rights reserved.

Pollutants from road traffic and breathing problems in children; Schadstoffe aus dem Strassenverkehr und Atemwegsbeschwerden bei Kindern

Energy Technology Data Exchange (ETDEWEB)

Mutius, E. von [Muenchen Univ. (Germany). Dr. von Haunersche Kinderklinik

1996-06-01

So far, there ave been few studies on measurable health effects of emissions from road traffic. An analysis of the available studies yields no clear indication of a relationship between road traffic emissions and the incidence of asthma and allergies in infants. On the other hand, there are no valid data on individual pollutant exposure of infants in the framework of epidemiological studies which take account of other influencing factors.(orig./MG) [Deutsch] Der Frag, ob eine Schadstoffbelastung durch den Strassenverkehr einen messbaren schaedigenden Effekt auf die menschliche Gesundheit hat, ist bislang in wenigen Studien nachgegangen worden. Analysiert man die vorliegenden Studien, ergibt sich derzeit kein eindeutiger Hinweis auf einen starken Zusammenhang zwischen der Strassenverkehrsbelastung und dem Auftreten von Asthma und Allergien beim Kind. Allerdings fehlt es an validen Daten zur individuellen Schadstoffexposition bei Kindern im Rahmen epidemiologischer Studien, ie eine Beruecksichtigung anderer Einfluss- und Stoervariablen erlauben. (orig/MG)

Sulphur self as a bioindicator of air pollution

International Nuclear Information System (INIS)

Sihelska, N.; Semerad, M.; Cernansky, S.; Ruzickova, J.; Takacova, A.

2015-01-01

Road transport is one of the major sources of air polluting emissions. An average passenger car produces emissions of 228 g/km, trucks produce emissions of around 317 g/km. Emissions from combustion engines contain carbon dioxide, water vapour, nitrogen oxides, ammonia, carbon monoxide, unburned hydrocarbons, sulphur dioxide and various solids. Emissions also contain compounds of toxic metals/metalloids - arsenic, cadmium, chrome, nickel and lead. To detect metal/metalloid contamination from vehicle emissions, samples were collected and analyzed from biomass and soil near Bratislava's busiest road. We focused our attention on concentration of metals/metalloids in Laetiporus sulphureus because it's a very popular edible mushroom. Mushrooms are very good proxies for the state of nearby environment because of their excellent accumulation ability. (authors)

NUMERICAL SIMULATION OF AIR POLLUTION IN CASE OF UNPLANNED AMMONIA RELEASE

Directory of Open Access Journals (Sweden)

L. V. Amelina

2017-06-01

Full Text Available Purpose. Development fast calculating model which takes into account the meteorological parameters and buildings which are situated near the source of toxic chemical emission. Methodology. The developed model is based on the equation for potential flow and equation of pollutant dispersion. Equation of potential flow is used to compute wind pattern among buildings. To solve equation for potential flow Samarskii implicit difference scheme is used. The implicit change – triangle difference scheme is used to solve equation of mass transfer. Numerical integration is carried out using the rectangular difference grid. Method of porosity technique («markers method» is used to create the form of comprehensive computational region. Emission of ammonia is modeled using Delta function for point source. Findings. Developed 2D numerical model belongs to the class of «diagnostic models». This model takes into account the main physical factors affecting the process of dispersion of pollutants in the atmosphere. The model takes into account the influence of buildings on pollutant dispersion. On the basis of the developed numerical models a computational experiment was carried out to estimate the level of toxic chemical pollution in the case of unplanned ammonia release at ammonia pump station. Originality. Developed numerical model allows to calculate the 2D wind pattern among buildings and pollutant dispersion in the case unplanned ammonia release. Model allows to perform fast calculations of the atmosphere pollution. Practical value. The model can be used when developing the PLAS (Emergency Response Plan.

Large-Eddy Simulation of pollutant dispersion in downtown Montreal: Evaluation of the convective and turbulent mass fluxes

NARCIS (Netherlands)

Gousseau, P.; Blocken, B.J.E.; Stathopoulos, T.; Heijst, van G.J.F.; Seppelt, R.; Voinov, A.A.; Lange, S.; Bankamp, D.

2012-01-01

Abstract: Large-Eddy Simulation of pollutant dispersion from a stack on the roof of a low-rise building in downtown Montreal is performed. Two wind directions are considered, with different wind flow patterns and plume behaviours. The resulting mean concentration field is observed and analysed with

Geophysical logging and thermal imaging near the Hemphill Road TCE National Priorities List Superfund site near Gastonia, North Carolina

Science.gov (United States)

Antolino, Dominick J.; Chapman, Melinda J.

2017-03-27

Borehole geophysical logs and thermal imaging data were collected by the U.S. Geological Survey near the Hemphill Road TCE (trichloroethylene) National Priorities List Superfund site near Gastonia, North Carolina, during August 2014 through February 2015. In an effort to assist the U.S. Environmental Protection Agency in the development of a conceptual groundwater model for the assessment of current contaminant distribution and future migration of contaminants, surface geological mapping and borehole geophysical log and thermal imaging data collection, which included the delineation of more than 600 subsurface features (primarily fracture orientations), was completed in five open borehole wells and two private supply bedrock wells. In addition, areas of possible groundwater discharge within a nearby creek downgradient of the study site were determined based on temperature differences between the stream and bank seepage using thermal imagery.

The comparison of summer air pollution by nitrogen dioxide in Ljubljana between 2005 and 2013

Directory of Open Access Journals (Sweden)

Matej Ogrin

2013-12-01

Full Text Available In Ljubljana, the air pollution by NO2 is mainly caused by transportation.The article focuses on traffic-related air pollution in three different types of urban space: urban background, open space near the roads, and street canyon.The measurement of concentrations perpendicular to the main city street is also presented. We compare the results of NO2 measuring campaigns in Ljubljana during the summers of 2005 and 2013. We seek to explain the reasons for the differences in the pollution of diverse urban space types and for the significant decrease of concentrations in all types of urban space.

Traffic-related air pollution exposure and incidence of stroke in four cohorts from Stockholm.

Science.gov (United States)

Korek, Michal J; Bellander, Tom D; Lind, Tomas; Bottai, Matteo; Eneroth, Kristina M; Caracciolo, Barbara; de Faire, Ulf H; Fratiglioni, Laura; Hilding, Agneta; Leander, Karin; Magnusson, Patrik K E; Pedersen, Nancy L; Östenson, Claes-Göran; Pershagen, Göran; Penell, Johanna C

2015-01-01

We investigated the risk of stroke related to long-term ambient air pollution exposure, in particular the role of various exposure time windows, using four cohorts from Stockholm County, Sweden. In total, 22,587 individuals were recruited from 1992 to 2004 and followed until 2011. Yearly air pollution levels resulting from local road traffic emissions were assessed at participant residences using dispersion models for particulate matter (PM10) and nitrogen oxides (NOX). Cohort-specific hazard ratios were estimated for time-weighted air pollution exposure during different time windows and the incidence of stroke, adjusted for common risk factors, and then meta-analysed. Overall, 868 subjects suffered a non-fatal or fatal stroke during 238,731 person-years of follow-up. An increment of 20 μg/m(3) in estimated annual mean of road-traffic related NOX exposure at recruitment was associated with a hazard ratio of 1.16 (95% CI 0.83-1.61), with evidence of heterogeneity between the cohorts. For PM10, an increment of 10 μg/m(3) corresponded to a hazard ratio of 1.14 (95% CI 0.68-1.90). Time-window analyses did not reveal any clear induction-latency pattern. In conclusion, we found suggestive evidence of an association between long-term exposure to NOX and PM10 from local traffic and stroke at comparatively low levels of air pollution.

Filtration effectiveness of HVAC systems at near-roadway schools.

Science.gov (United States)

McCarthy, M C; Ludwig, J F; Brown, S G; Vaughn, D L; Roberts, P T

2013-06-01

Concern for the exposure of children attending schools located near busy roadways to toxic, traffic-related air pollutants has raised questions regarding the environmental benefits of advanced heating, ventilation, and air-conditioning (HVAC) filtration systems for near-road pollution. Levels of black carbon and gaseous pollutants were measured at three indoor classroom sites and at seven outdoor monitoring sites at Las Vegas schools. Initial HVAC filtration systems effected a 31-66% reduction in black carbon particle concentrations inside three schools compared with ambient air concentrations. After improved filtration systems were installed, black carbon particle concentrations were reduced by 74-97% inside three classrooms relative to ambient air concentrations. Average black carbon particle concentrations inside the schools with improved filtration systems were lower than typical ambient Las Vegas concentrations by 49-96%. Gaseous pollutants were higher indoors than outdoors. The higher indoor concentrations most likely originated at least partially from indoor sources, which were not targeted as part of this intervention. Recent literature has demonstrated adverse health effects in subjects exposed to ambient air near major roadways. Current smart growth planning and infill development often require that buildings such as schools are built near major roadways. Improving the filtration systems of a school's HVAC system was shown to decrease children's exposure to near-roadway diesel particulate matter. However, reducing exposure to the gas-phase air toxics, which primarily originated from indoor sources, may require multiple filter passes on recirculated air. © 2012 John Wiley & Sons A/S. Published by Blackwell Publishing Ltd.

Testing of cavity attenuation phase shift technology for siting near-road NO2 monitors.

Science.gov (United States)

2015-07-01

Recent research has identified the public health importance of air pollution exposures : near busy roadways. As a result, EPA significantly revised its NO2 air quality standard in 2010. : The current regulatory focus has shifted from assessment of lo...

Trees and Streets as Drivers of Urban Stormwater Nutrient Pollution.

Science.gov (United States)

Janke, Benjamin D; Finlay, Jacques C; Hobbie, Sarah E

2017-09-05

Expansion of tree cover is a major management goal in cities because of the substantial benefits provided to people, and potentially to water quality through reduction of stormwater volume by interception. However, few studies have addressed the full range of potential impacts of trees on urban runoff, which includes deposition of nutrient-rich leaf litter onto streets connected to storm drains. We analyzed the influence of trees on stormwater nitrogen and phosphorus export across 19 urban watersheds in Minneapolis-St. Paul, MN, U.S.A., and at the scale of individual streets within one residential watershed. Stormwater nutrient concentrations were highly variable across watersheds and strongly related to tree canopy over streets, especially for phosphorus. Stormwater nutrient loads were primarily related to road density, the dominant control over runoff volume. Street canopy exerted opposing effects on loading, where elevated nutrient concentrations from trees near roads outweighed the weak influence of trees on runoff reduction. These results demonstrate that vegetation near streets contributes substantially to stormwater nutrient pollution, and therefore to eutrophication of urban surface waters. Urban landscape design and management that account for trees as nutrient pollution sources could improve water quality outcomes, while allowing cities to enjoy the myriad benefits of urban forests.

Ground-level airborne particulate matter near important Portuguese Cultural Heritage sites in high polluted (Lisbon) and low polluted (Evora) urban environments

Science.gov (United States)

Schiavon, N.; Wagner, F.; Candeias, A.; Kandler, K.; Tobias, L.; Mirao, J.

2012-04-01

As part of a wider project on aerosol composition in the Southwestern part of the Iberian peninsula, an intensive field monitoring/sampling/analytical campaign has been conducted in August and December 2011 to assess indoor and outdoor atmospheric aerosol optical and microphysical parameters (Nephelometry), number/mass/size distribution (TEOM, MAAP, OPS) and single particle minero-chemical composition on filter collected samples (VP-SEM+EDS, XRD) at several sheltered and unsheltered locations close to important Cultural Heritage monuments in Evora and Lisbon, Portugal. Sites investigated included the Igreja do S. Francisco in Evora, the Cristo Rei sanctuary, Jeronimos Monastery, and Lisbon Castle in Lisbon. At Cristo Rei measurements at sea level, around 100m and around 180m were carried out in order to determine the vertical profile of the particle size distribution. Measurements were taken at different times of day reflecting changes in atmospheric mixing and air pollution levels. Measurements were also performed near an air quality monitoring station at Avenida de Libertade (the busiest traffic artery in Lisbon city center) during traffic peak hour. One of the aims of the campaign was to determine differences in airborne particulate matter compositions and concentrations between an urban coastal high pollution (Lisbon) and a low pollution (Evora) environments and how these could affect the nature of decay patterns and processes in the building materials of the monuments under investigation. Preliminary results indicate significant differences in particle properties between the 2 cities as well as between indoor and outdoor locations. One interesting result was the detection of considerable amounts of particle of oceanic origin (such as sodium chloride) in the Evora site even at 130 km away from the coast. Despite its relatively unpolluted location, single particle analysis by SEM+EDS at the Evora site reveals the presence of significant numbers of particle of

Atmospheric dispersion modeling of hazardous air pollutant emissions from USDOE Oak Ridge Reservation Facilities. Volume 1, Independent Assessment conducted from April 1994 to December 1994

International Nuclear Information System (INIS)

Humphreys, M.P.

1995-01-01

Title 3 of the 1990 Clean Air Act (CAA) Amendments addresses the emissions of 189 hazardous air pollutants (HAPs) and mandates that EPA develop technology-based [Maximum Achievable Control Technology (MACT)] standards for the control of these pollutants from approximately 174 source categories. After implementation of technology-based standards, EPA is required to further evaluate ''residual risk'' from HAP emissions, and, if required, develop more stringent standards to protect human health and the environment with an ''adequate margin of safety''. Recognizing that EPA will be issuing risk-based regulations after MACT standards have been implemented, the US Department of Energy (DOE), Oak Ridge Operations Office (ORO) has conducted an evaluation of ambient air impacts of HAP emissions from its installations located on the Oak Ridge Reservation (ORR) near Oak Ridge, Tennessee. This report provides results of atmospheric dispersion modeling conducted to determine ambient air impacts of HAP emissions from facilities located on the ORR

A comparative study of noise pollution levels in some selected areas in Ilorin Metropolis, Nigeria.

Science.gov (United States)

Oyedepo, Olayinka S; Saadu, Abdullahi A

2009-11-01

The noise pollution is a major problem for the quality of life in urban areas. This study was conducted to compare the noise pollution levels at busy roads/road junctions, passengers loading parks, commercial, industrial and residential areas in Ilorin metropolis. A total number of 47-locations were selected within the metropolis. Statistical analysis shows significant difference (P noise pollution levels between industrial areas and low density residential areas, industrial areas and high density areas, industrial areas and passengers loading parks, industrial areas and commercial areas, busy roads/road junctions and low density areas, passengers loading parks and commercial areas and commercial areas and low density areas. There is no significant difference (P > 0.05) in noise pollution levels between industrial areas and busy roads/road junctions, busy roads/road junctions and high density areas, busy roads/road junctions and passengers loading parks, busy roads/road junctions and commercial areas, passengers loading parks and high density areas, passengers loading parks and commercial areas and commercial areas and high density areas. The results show that Industrial areas have the highest noise pollution levels (110.2 dB(A)) followed by busy roads/Road junctions (91.5 dB(A)), Passengers loading parks (87.8 dB(A)) and Commercial areas (84.4 dB(A)). The noise pollution levels in Ilorin metropolis exceeded the recommended level by WHO at 34 of 47 measuring points. It can be concluded that the city is environmentally noise polluted and road traffic and industrial machineries are the major sources of it. Noting the noise emission standards, technical control measures, planning and promoting the citizens awareness about the high noise risk may help to relieve the noise problem in the metropolis.

Numerical modeling of flow and pollutant dispersion in street canyons with tree planting

Energy Technology Data Exchange (ETDEWEB)

Balczo, Marton [Budapest Univ. of Technology and Economics (Hungary). Theodore von Karman Wind Tunnel Lab.; Gromke, Christof; Ruck, Bodo [Karlsruhe Univ. (Germany). Lab. of Building- and Environmental Aerodynamics

2009-04-15

Numerical simulations of the impact of tree planting on airflow and traffic pollutant dispersion in urban street canyons have been performed using the commercial CFD (Computational Fluid Dynamics) code MISKAM. A {kappa}-{epsilon} turbulence model including additional terms for the treatment of vegetation, has been employed to close the Reynolds-averaged-Navier-Stokes (RANS) equations. The numerical results were compared to wind tunnel data. In the case of the investigated wind direction perpendicular to the street axis, the presence of trees lead to increased pollutant concentrations inside the canyon. Concentrations increased strongly on the upstream side of the canyon, while on the downstream side a small concentration decrease could be observed. Lower flow velocities and higher pollutant concentrations were found in the numerical simulations when directly compared to the experimental results. However, the impact of tree planting on airflow and concentration fields when compared to the treeless street canyon as a reference configuration were simulated quite well, meaning that relative changes were similar in the wind tunnel investigations and numerical computations. This feature qualifies MISKAM for use as a tool for assessing the impacts of vegetation on local air quality. (orig.)

ATMOSPHERIC DYNAMICS OF AIR POLLUTION DISPERSION AND SUSTAINABLE ENVIRONMENT IN JOS-NIGERIA

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Moses Eterigho Emetere

2017-01-01

Full Text Available The basic properties of chlorine were used to determine the dis persion patterns of the recent Jos explosion. The dynamic aerosols content model was us ed to affirm the eight kinds of dispersion patterns discussed in this text. The locati on of the victims showed that the dispersion at Jos was either linear or polynomial disp ersion. The dispersions are influenced by atmospheric ventilation, stagnation and recir culation. The last chlorine gas explosion follows the linear or polynomial dispers ion because of the current state of aerosol loadings in Jos. The aftermath effect of this kind of dispersion may be more threatening than the initial danger due to the chem ical formation of more dangerous compounds. The atmosphe ric conditions for the formati on of toxic compound were investigated using twelve years MERRA satellite o bservation. The degree of freedom of methane, carbon oxide and ozone was nearly uniform for the past five years. This means the next five years or more may be threa tening for life forms within the region. The installation of gas tracers within major locations in Jos was suggested to monitor the formation of dioxins in the atmosphere.

CASE STUDY. MERCURY POLLUTION NEAR A CHEMICAL PLANT IN NORTHERN KAZAKHSTAN

Science.gov (United States)

In northern Kazakhstan, there is a serious case of mercury pollution near Pavlodar City from an old mercury cell chlor-alkali plant. The soil, sediment, and water are contaminated with more than a thousand tons of mercury and mercury compounds as a result of the operation of the ...

Air pollution meteorology

Energy Technology Data Exchange (ETDEWEB)

Shirvaikar, V V; Daoo, V J [Environmental Assessment Div., Bhabha Atomic Research Centre, Mumbai (India)

2002-06-01

This report is intended as a training cum reference document for scientists posted at the Environmental Laboratories at the Nuclear Power Station Sites and other sites of the Department of Atomic Energy with installations emitting air pollutants, radioactive or otherwise. Since a manual already exists for the computation of doses from radioactive air pollutants, a general approach is take here i.e. air pollutants in general are considered. The first chapter presents a brief introduction to the need and scope of air pollution dispersion modelling. The second chapter is a very important chapter discussing the aspects of meteorology relevant to air pollution and dispersion modelling. This chapter is important because without this information one really does not understand the phenomena affecting dispersion, the scope and applicability of various models or their limitations under various weather and site conditions. The third chapter discusses the air pollution models in detail. These models are applicable to distances of a few tens of kilometres. The fourth chapter discusses the various aspects of meteorological measurements relevant to air pollution. The chapters are followed by two appendices. Apendix A discusses the reliability of air pollution estimates. Apendix B gives some practical examples relevant to general air pollution. It is hoped that the document will prove very useful to the users. (author)

EnviroAtlas - Des Moines, IA - Near Road Block Group Summary

Data.gov (United States)

U.S. Environmental Protection Agency — This EnviroAtlas dataset addresses the tree buffer along heavily traveled roads. The roads are interstates, arterials, and collectors within the EnviroAtlas...

EnviroAtlas - Minneapolis/St. Paul, MN - Near Road Tree Buffer

Data.gov (United States)

U.S. Environmental Protection Agency — This EnviroAtlas dataset addresses the tree buffer along heavily traveled roads. The roads are interstates, arterials, and collectors within the EnviroAtlas...

EnviroAtlas - New York, NY - Near Road Block Group Summary

Data.gov (United States)

U.S. Environmental Protection Agency — This EnviroAtlas dataset addresses the tree buffer along heavily traveled roads. The roads are interstates, arterials, and collectors within the EnviroAtlas...

EnviroAtlas - Green Bay, WI - Near Road Block Group Summary

Data.gov (United States)

U.S. Environmental Protection Agency — This EnviroAtlas dataset addresses the tree buffer along heavily traveled roads. The roads are interstates, arterials, and collectors within the EnviroAtlas...

EnviroAtlas - New Bedford, MA - Near Road Block Group Summary

Data.gov (United States)

U.S. Environmental Protection Agency — This EnviroAtlas dataset addresses the tree buffer along heavily traveled roads. The roads are interstates, arterials, and collectors within the EnviroAtlas...

Environmentally friendly road construction

Directory of Open Access Journals (Sweden)

A.I. Essawy

2013-06-01

Full Text Available Environmental pollution is a major problem in developing countries like Egypt. Reuse of waste polymers is considered an attractive solution for environmental white pollution and reducing of the costs of road pavement and maintenance. This research aims to prepare environmentally friendly hot mix asphalt (HMA for paving using some industrial wastes as polypropylene and polyester fibers. The solid materials in the mix include normal and highly porous aggregates. 5% and 10% of waste polymers by weight of the asphalt were used to prepare special binders. The samples were tested for their physical properties, chemical properties, aging, scanning electron microscopy (SEM and thermo-gravimetric analysis (TGA. The results revealed that the prepared HMA using 5% of waste polymer had high performance as compared to the ordinary one and the waste polymer could be used in road construction.

Residential proximity to major roads and obstetrical complications.

Science.gov (United States)

Yorifuji, Takashi; Naruse, Hiroo; Kashima, Saori; Murakoshi, Takeshi; Doi, Hiroyuki

2015-03-01

Exposure to air pollution is linked with an increased risk of preterm births. To provide further evidence on this relationship, we evaluated the association between proximity to major roads--as an index for air pollution exposure--and various obstetrical complications. Data were extracted from a database maintained by the perinatal hospital in Shizuoka, Japan. We restricted the analysis to mothers with singleton pregnancies of more than 22 weeks of gestation from 1997 to 2012 (n=19,077). Using the geocoded residential information, each mother was assigned proximity to major roads. We then estimated multivariate adjusted odds ratios and their 95% confidence intervals (CIs) for the effects of proximity to major roads on various obstetrical complications (preeclampsia, gestational diabetes mellitus, placenta abruption, placenta previa, preterm premature rupture of membrane (pPROM), preterm labor, and preterm births). We found positive associations of proximity to major roads with preeclampsia and pPROM. Living within 200 m increased the odds of preeclampsia by 1.3 times (95% CI, 1.0-1.8) and pPROM by 1.6 times (95% CI, 1.1-2.2). Furthermore, living within 200 m increased the odds of preterm births by 1.4 fold (95% CI, 1.2-1.7). Exposure to traffic-related air pollution increased the risk of preeclampsia and pPROM in this study. We propose a mechanism responsible for the association between air pollution and preterm births. Copyright © 2014 Elsevier B.V. All rights reserved.

Respiratory effects of particulate matter air pollution: studies on diesel exhaust, road tunnel, subway and wood smoke exposure in human subjects

Energy Technology Data Exchange (ETDEWEB)

Sehlstedt, Maria

2011-07-01

Background: Ambient air pollution is associated with adverse health effects, but the sources and components, which cause these effects is still incompletely understood. The aim of this thesis was to investigate the pulmonary effects of a variety of common air pollutants, including diesel exhaust, biomass smoke, and road tunnel and subway station environments. Healthy non-smoking volunteers were exposed in random order to the specific air pollutants and air/control, during intermittent exercise, followed by bronchoscopy. Methods and results: In study I, exposures were performed with diesel exhaust (DE) generated at transient engine load and air for 1 hour with bronchoscopy at 6 hours post-exposure. Immunohistochemical analyses of bronchial mucosal biopsies showed that DE exposure significantly increased the endothelial adhesion molecule expression of p-selectin and VCAM-1, together with increased bronchoalveolar lavage (BAL) eosinophils. In study II, the subjects were exposed for 1 hour to DE generated during idling with bronchoscopy at 6 hours. The bronchial mucosal biopsies showed significant increases in neutrophils, mast cells and lymphocytes together with bronchial wash neutrophils. Additionally, DE exposure significantly increased the nuclear translocation of the aryl hydrocarbon receptor (AhR) and phosphorylated c-jun in the bronchial epithelium. In contrast, the phase II enzyme NAD(P)H-quinone oxidoreductase 1 (NQO1) decreased after DE. In study III, the 2-hour exposures took place in a road tunnel with bronchoscopy 14 hours later. The road tunnel exposure significantly increased the total numbers of lymphocytes and alveolar macrophages in BAL, whereas NK cell and CD56+/T cell numbers significantly decreased. Additionally, the nuclear expression of phosphorylated c-jun in the bronchial epithelium was significantly increased after road tunnel exposure. In study IV, the subjects were exposed to metal-rich particulate aerosol for 2 hours at a subway station

Large eddy simulation of pollutant gas dispersion with buoyancy ejected from building into an urban street canyon.

Science.gov (United States)

Hu, L H; Xu, Y; Zhu, W; Wu, L; Tang, F; Lu, K H

2011-09-15

The dispersion of buoyancy driven smoke soot and carbon monoxide (CO) gas, which was ejected out from side building into an urban street canyon with aspect ratio of 1 was investigated by large eddy simulation (LES) under a perpendicular wind flow. Strong buoyancy effect, which has not been revealed before, on such pollution dispersion in the street canyon was studied. The buoyancy release rate was 5 MW. The wind speed concerned ranged from 1 to 7.5m/s. The characteristics of flow pattern, distribution of smoke soot and temperature, CO concentration were revealed by the LES simulation. Dimensionless Froude number (Fr) was firstly introduced here to characterize the pollutant dispersion with buoyancy effect counteracting the wind. It was found that the flow pattern can be well categorized into three regimes. A regular characteristic large vortex was shown for the CO concentration contour when the wind velocity was higher than the critical re-entrainment value. A new formula was theoretically developed to show quantitatively that the critical re-entrainment wind velocities, u(c), for buoyancy source at different floors, were proportional to -1/3 power of the characteristic height. LES simulation results agreed well with theoretical analysis. The critical Froude number was found to be constant of 0.7. Copyright © 2010 Elsevier B.V. All rights reserved.

Pollutant dispersion in boundary layers exposed to rural-to-urban transitions : Varying the spanwise length scale of the roughness

NARCIS (Netherlands)

Tomas, J.M.; Eisma, H.E.; Pourquie, M.J.B.M.; Elsinga, G.E.; Jonker, H.J.J.; Westerweel, J.

2017-01-01

Both large-eddy simulations (LES) and water-tunnel experiments, using simultaneous stereoscopic particle image velocimetry and laser-induced fluorescence, have been used to investigate pollutant dispersion mechanisms in regions where the surface changes from rural to urban roughness. The urban

Simulation of trace metals and PAH atmospheric pollution over Greater Paris: Concentrations and deposition on urban surfaces

Science.gov (United States)

Thouron, L.; Seigneur, C.; Kim, Y.; Legorgeu, C.; Roustan, Y.; Bruge, B.

2017-10-01

Urban areas can be subject not only to poor air quality, but also to contamination of other environmental media by air pollutants. Here, we address the potential transfer of selected air pollutants (two metals and three PAH) to urban surfaces. To that end, we simulate meteorology and air pollution from Europe to a Paris suburban neighborhood, using a four-level one-way nesting approach. The meteorological and air quality simulations use urban canopy sub-models in order to better represent the effect of the urban morphology on the air flow, atmospheric dispersion, and deposition of air pollutants to urban surfaces. This modeling approach allows us to distinguish air pollutant deposition among various urban surfaces (roofs, roads, and walls). Meteorological model performance is satisfactory, showing improved results compared to earlier simulations, although precipitation amounts are underestimated. Concentration simulation results are also satisfactory for both metals, with a fractional bias Paris region. The model simulation results suggest that both wet and dry deposition processes need to be considered when estimating the transfer of air pollutants to other environmental media. Dry deposition fluxes to various urban surfaces are mostly uniform for PAH, which are entirely present in fine particles. However, there is significantly less wall deposition compared to deposition to roofs and roads for trace metals, due to their coarse fraction. Meteorology, particle size distribution, and urban morphology are all important factors affecting air pollutant deposition. Future work should focus on the collection of data suitable to evaluate the performance of atmospheric models for both wet and dry deposition with fine spatial resolution.

Simulation of Population-Based Commuter Exposure to NO2 Using Different Air Pollution Models

Directory of Open Access Journals (Sweden)

Martina S. Ragettli

2014-05-01

Full Text Available We simulated commuter routes and long-term exposure to traffic-related air pollution during commute in a representative population sample in Basel (Switzerland, and evaluated three air pollution models with different spatial resolution for estimating commute exposures to nitrogen dioxide (NO2 as a marker of long-term exposure to traffic-related air pollution. Our approach includes spatially and temporally resolved data on actual commuter routes, travel modes and three air pollution models. Annual mean NO2 commuter exposures were similar between models. However, we found more within-city and within-subject variability in annual mean (±SD NO2 commuter exposure with a high resolution dispersion model (40 ± 7 µg m−3, range: 21–61 than with a dispersion model with a lower resolution (39 ± 5 µg m−3; range: 24–51, and a land use regression model (41 ± 5 µg m−3; range: 24–54. Highest median cumulative exposures were calculated along motorized transport and bicycle routes, and the lowest for walking. For estimating commuter exposure within a city and being interested also in small-scale variability between roads, a model with a high resolution is recommended. For larger scale epidemiological health assessment studies, models with a coarser spatial resolution are likely sufficient, especially when study areas include suburban and rural areas.

Self-reported exposure to traffic pollution in relation to daytime sleepiness and habitual snoring: a questionnaire study in seven North-European cities.

Science.gov (United States)

Gislason, Thorarinn; Bertelsen, Randi J; Real, Francisco Gomez; Sigsgaard, Torben; Franklin, Karl A; Lindberg, Eva; Janson, Christer; Arnardottir, Erna Sif; Hellgren, Johan; Benediktsdottir, Bryndis; Forsberg, Bertil; Johannessen, Ane

2016-08-01

Little is known about associations between traffic exposure and sleep disturbances. We examined if self-reported exposure to traffic is associated with habitual snoring and daytime sleepiness in a general population. In the RHINE III study, 12184 adults answered questions on sleep disturbances and traffic exposure. We analysed bedrooms near roads with traffic, bedrooms with traffic noise, and travelling regularly along busy roads as proxies for traffic exposures, using logistic regression. Adjustment factors were study centre, gender, age, smoking habits, educational level, body mass index, physical activity, obstructive sleep apnoea, and sleep duration. One in ten lived near a busy road, 6% slept in a bedroom with traffic noise, and 11% travelled regularly along busy roads. Habitual snoring affected 25% and daytime sleepiness 21%. More men reported snoring and more women reported daytime sleepiness. Having a bedroom with traffic noise was associated with snoring (adjusted OR 1.29, [95% CI 1.12, 1.48]). For daytime sleepiness, on the other hand, bedroom with traffic noise and high exposure to traffic pollution have significant risk factors (adjusted ORs 1.46 [1.11, 1.92] and 1.65 [1.11, 2.45]). Results were consistent across study centres. Daytime sleepiness is associated with traffic pollution and traffic noise, while habitual snoring is only associated with traffic noise. Self-reported traffic exposure should be taken into account when diagnosing and planning treatment for patients with sleep disturbances, because reducing noise and pollution exposure in the bedroom may have a beneficial effect. Copyright © 2016 Elsevier B.V. All rights reserved.

A Location Intelligence System for the Assessment of Pluvial Flooding Risk and the Identification of Storm Water Pollutant Sources from Roads in Suburbanised Areas

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Szymon Szewrański

2018-06-01

Full Text Available The interplay of an ever-growing number of inhabitants, sprawl development, soil sealing, changes in urban traffic characteristics, as well as observed climate trends gives rise to more frequent pluvial flooding in cities, a higher run-off of water, and an increasing pollution of surface water. The aim of this research is to develop a location intelligence system for the assessment of pluvial flooding risks and the identification of storm water pollutant sources from roads in newly-developed areas. The system combines geographic information systems and business intelligence software, and it is based on the original Pluvial Flood Risk Assessment tool. The location intelligence system effectively identifies the spatial and temporal distribution of pluvial flood risks, allows to preliminarily evaluate the total run-off from roads, and helps localise potential places for new water management infrastructure. Further improvements concern the modelling of a flow accumulation and drainage system, the application of weather radar precipitation data, and traffic monitoring and modelling.

Air pollution

OpenAIRE

MacKenbach, JP; Henschel, S; Goodman, P; McKee, M

2013-01-01

The human costs of air pollution are considerable in Jordan. According to a report published in 2000 by the World Bank under the Mediterranean Environmental Technical Assistance Program (METAP), approximately 600 people die prematurely each year in Jordan because of urban pollution. 50-90% of air pollution in Jordanian towns is caused by road traffic. Readings taken in 2007 by Jordanian researchers showed that levels of black carbon particles in the air were higher in urban areas (caused by v...

Comparison of Land-Use Regression Modeling with Dispersion and Chemistry Transport Modeling to Assign Air Pollution Concentrations within the Ruhr Area

Directory of Open Access Journals (Sweden)

Frauke Hennig

2016-03-01

Full Text Available Two commonly used models to assess air pollution concentration for investigating health effects of air pollution in epidemiological studies are Land Use Regression (LUR models and Dispersion and Chemistry Transport Models (DCTM. Both modeling approaches have been applied in the Ruhr area, Germany, a location where multiple cohort studies are being conducted. Application of these different modelling approaches leads to differences in exposure estimation and interpretation due to the specific characteristics of each model. We aimed to compare both model approaches by means of their respective aims, modeling characteristics, validation, temporal and spatial resolution, and agreement of residential exposure estimation, referring to the air pollutants PM2.5, PM10, and NO2. Residential exposure referred to air pollution exposure at residences of participants of the Heinz Nixdorf Recall Study, located in the Ruhr area. The point-specific ESCAPE (European Study of Cohorts on Air Pollution Effects-LUR aims to temporally estimate stable long-term exposure to local, mostly traffic-related air pollution with respect to very small-scale spatial variations (≤100 m. In contrast, the EURAD (European Air Pollution Dispersion-CTM aims to estimate a time-varying average air pollutant concentration in a small area (i.e., 1 km2, taking into account a range of major sources, e.g., traffic, industry, meteorological conditions, and transport. Overall agreement between EURAD-CTM and ESCAPE-LUR was weak to moderate on a residential basis. Restricting EURAD-CTM to sources of local traffic only, respective agreement was good. The possibility of combining the strengths of both applications will be the next step to enhance exposure assessment.

Road Fatality Model Based on Over-Dispersion Data Along Federal Route F0050

Directory of Open Access Journals (Sweden)

Musa Wan Zahidah

2017-01-01

Full Text Available According to The World Health Ranking 2011 has ranked Malaysia as 20th in its list of countries with the most deaths caused by road accidents. Road accidents also have been identified as the prime cause of death in Malaysia after the heart disease, stroke, influenza and pneumonia. To date, previous researches from Malaysian Institute of Road Safety (MIROS have reported that averages of 18 people were killed on Malaysian road daily. There are many kinds of models that have been developed in modelling the circumstance of accidents. The most widely applied was Poisson and Negative Binomial regression models while Zeroinflated Poisson and Zero-inflated Negative Binomial are the modification of Poisson and Negative Binomials regression models. This study interested to focus on road F0050 as statistic data from Royal Malaysian Police 2014 list F0050 as one of the high accident road in Malaysia from kilometre 0 until kilometre 58. R programming was chose to analyse the relationship between road fatality and its factor (annual average daily traffic (AADT, speed, shoulder width, lane width. Negative binomial and Zero-inflated negative binomial (ZINB were shown to be preferred modelling methods for this study. Significant positive relationships were also identified between road fatality and annual average daily traffic (AADT and lane width. This relationship can be a helpful support to the decision making of accident management for road F0050.

MOSSES AND LICHENS – BIOINDICATORS OF HEAVY METALS POLLUTION OF FOREST ECOSYSTEMS

Directory of Open Access Journals (Sweden)

BEGU A.

2014-03-01

Full Text Available This study is a comparative investigation of the content of heavy metals (Pb, Cu, Ni, Zn and Cr in mosses and lichens recorded in ten deciduous forests in the Republic of Moldova included in a transnational grid (16x16 km of forest monitoring throughout Europe. The content of heavy metals doesn’t differ significant by depending on the location of studied forest ecosystems. The trends of larger accumulation are observed near the local stationary and mobile sources of pollution. Mosses were confirmed as good indicators of air pollution with heavy metals to forest ecosystems located near sources of pollution and lichens show good bio-indicators particularities for background pollution. The good correlation between the concentrations of moss and lichen were Cr, Cu and Ni, and the low correlation between Pb and Zn, which are considered to be metals which are amenable to long-distance dispersal.

Characterizing polycyclic aromatic hydrocarbon build-up processes on urban road surfaces

International Nuclear Information System (INIS)

Liu, Liang; Liu, An; Li, Dunzhu; Zhang, Lixun; Guan, Yuntao

2016-01-01

Reliable prediction models are essential for modeling pollutant build-up processes on urban road surfaces. Based on successive samplings of road deposited sediments (RDS), this study presents empirical models for mathematical replication of the polycyclic aromatic hydrocarbon (PAH) build-up processes on urban road surfaces. The contaminant build-up behavior was modeled using saturation functions, which are commonly applied in US EPA's Stormwater Management Model (SWMM). Accurate fitting results were achieved in three typical urban land use types, and the applicability of the models was confirmed based on their acceptable relative prediction errors. The fitting results showed high variability in PAH saturation value and build-up rate among different land use types. Results of multivariate data and temporal-based analyses suggested that the quantity and property of RDS significantly influenced PAH build-up. Furthermore, pollution sources, traffic parameters, road surface conditions, and sweeping frequency could synthetically impact the RDS build-up and RDS property change processes. Thus, changes in these parameters could be the main reason for variations in PAH build-up in different urban land use types. - Highlights: • Sufficient robust prediction models were established for analysis of PAH build-up on urban road surfaces. • PAH build-up processes showed high variability among different land use types. • Pollution sources as well as the quantity and property of RDS mainly influenced PAH build-up. - Sufficient robust prediction models were established for analysis of PAH build-up on urban road surfaces. Pollution sources as well as the quantity and property of RDS mainly influenced PAH build-up.

How and when urban vehicular traffic pollutes the environment

International Nuclear Information System (INIS)

Cera, L.; Di Mascio, P.

1993-01-01

This paper first compares monitored values of urban traffic air and noise pollution with Italian and European Communities pollution limits to assess the efficacy of current and proposed pollution regulations. The paper then focuses on the environmental impacts of the generation and discharge of waste waters during the construction and use of road surfaces. The related problems discussed include: soil erosion due to the increased exposure of bordering terrestrial ecosystems to damaging atmospheric pollutants; and the reception by roadside land areas of pollutants absorbed in rainfall runoff which has come into contact with road surfaces. Some suggestions are made on how to abate these particular types of traffic derived pollutants

Numerical study of dispersing pollutant clouds in a built-up environment

International Nuclear Information System (INIS)

Wang Bingchen; Yee, Eugene; Lien, F.-S.

2009-01-01

In this paper, we study numerically the dispersion of a passive scalar released from an instantaneous point source in a built-up (urban) environment using a Reynolds-averaged Navier-Stokes method. A nonlinear k-ε turbulence model [Speziale, C.G., 1987. On nonlinear k-l and k-ε models of turbulence. J. Fluid Mech., 178, 459-475] was used for the closure of the mean momentum equations. A tensor diffusivity model [Yoshizawa, A., 1985. Statistical analysis of the anisotropy of scalar diffusion in turbulent shear flows. Phys. Fluids, 28, 3226-3231] was used for closure of the scalar transport equations. The concentration variance was also calculated from its transport equation, for which new values of Yoshizawa's closure coefficients are used, in order to account for the instantaneous tracer release and the complex geometry. A new dissipation length-scale model, required for the modelling of the dissipation rate of concentration variance, is also proposed. The numerical results for the flow, the pollutant concentration and the concentration variance, are compared with experimental data. This data was obtained from a water-channel simulation of a full-scale field experiment of tracer dispersion through a large array of building-like obstacles known as the Mock Urban Setting Trial (MUST)

Numerical study of dispersing pollutant clouds in a built-up environment

Energy Technology Data Exchange (ETDEWEB)

Wang Bingchen [Department of Mechanical and Manufacturing Engineering, University of Manitoba, 75A Chancellors Circle, Winnipeg, Manitoba, R3T 5V6 (Canada)], E-mail: bc_wang@umanitoba.ca; Yee, Eugene [Defence Research and Development Canada - Suffield, P.O. Box 4000, STN Main, Medicine Hat, AB, T1A 8K6 (Canada)], E-mail: eugene.yee@drdc-rddc.gc.ca; Lien, F.-S. [Department of Mechanical and Mechatronics Engineering, University of Waterloo, Waterloo, Ontario, N2L 3G1 (Canada)], E-mail: fslien@mecheng1.uwaterloo.ca

2009-02-15

In this paper, we study numerically the dispersion of a passive scalar released from an instantaneous point source in a built-up (urban) environment using a Reynolds-averaged Navier-Stokes method. A nonlinear k-{epsilon} turbulence model [Speziale, C.G., 1987. On nonlinear k-l and k-{epsilon} models of turbulence. J. Fluid Mech., 178, 459-475] was used for the closure of the mean momentum equations. A tensor diffusivity model [Yoshizawa, A., 1985. Statistical analysis of the anisotropy of scalar diffusion in turbulent shear flows. Phys. Fluids, 28, 3226-3231] was used for closure of the scalar transport equations. The concentration variance was also calculated from its transport equation, for which new values of Yoshizawa's closure coefficients are used, in order to account for the instantaneous tracer release and the complex geometry. A new dissipation length-scale model, required for the modelling of the dissipation rate of concentration variance, is also proposed. The numerical results for the flow, the pollutant concentration and the concentration variance, are compared with experimental data. This data was obtained from a water-channel simulation of a full-scale field experiment of tracer dispersion through a large array of building-like obstacles known as the Mock Urban Setting Trial (MUST)

Treatment conditions for the removal of contaminants from road runoff

OpenAIRE

Hallberg, Magnus

2007-01-01

The pollutant load in road runoff is related to traffic densities and road maintenance activities. Inurbanised areas treatment of road runoff is common and often considered necessary. The pollutantsare partitioned between the particulate and dissolved matter. However, the contaminantstend to have an affinity to the particulate material. Sedimentation, the predominant treatmentmethod for road runoff uses various types of ponds. Design tools used for stormwater treatmentsystems are based on ext...

Dispersal networks for enhancing bacterial degradation in heterogeneous environments

International Nuclear Information System (INIS)

Banitz, Thomas; Wick, Lukas Y.; Fetzer, Ingo; Frank, Karin; Harms, Hauke; Johst, Karin

2011-01-01

Successful biodegradation of organic soil pollutants depends on their bioavailability to catabolically active microorganisms. In particular, environmental heterogeneities often limit bacterial access to pollutants. Experimental and modelling studies revealed that fungal networks can facilitate bacterial dispersal and may thereby improve pollutant bioavailability. Here, we investigate the influence of such bacterial dispersal networks on biodegradation performance under spatially heterogeneous abiotic conditions using a process-based simulation model. To match typical situations in polluted soils, two types of abiotic conditions are studied: heterogeneous bacterial dispersal conditions and heterogeneous initial resource distributions. The model predicts that networks facilitating bacterial dispersal can enhance biodegradation performance for a wide range of these conditions. Additionally, the time horizon over which this performance is assessed and the network's spatial configuration are key factors determining the degree of biodegradation improvement. Our results support the idea of stimulating the establishment of fungal mycelia for enhanced bioremediation of polluted soils. - Highlights: → Bacterial dispersal networks can considerably improve biodegradation performance. → They facilitate bacterial access to dispersal-limited areas and remote resources. → Abiotic conditions, time horizon and network structure govern the improvements. → Stimulating the establishment of fungal mycelia promises enhanced soil remediation. - Simulation modelling demonstrates that fungus-mediated bacterial dispersal can considerably improve the bioavailability of organic pollutants under spatially heterogeneous abiotic conditions typical for water-unsaturated soils.

Dispersal networks for enhancing bacterial degradation in heterogeneous environments

Energy Technology Data Exchange (ETDEWEB)

Banitz, Thomas, E-mail: thomas.banitz@ufz.de [Department of Ecological Modelling, UFZ - Helmholtz Centre for Environmental Research, Permoserstr. 15, 04318 Leipzig (Germany); Wick, Lukas Y.; Fetzer, Ingo [Department of Environmental Microbiology, UFZ - Helmholtz Centre for Environmental Research, Permoserstr. 15, 04318 Leipzig (Germany); Frank, Karin [Department of Ecological Modelling, UFZ - Helmholtz Centre for Environmental Research, Permoserstr. 15, 04318 Leipzig (Germany); Harms, Hauke [Department of Environmental Microbiology, UFZ - Helmholtz Centre for Environmental Research, Permoserstr. 15, 04318 Leipzig (Germany); Johst, Karin [Department of Ecological Modelling, UFZ - Helmholtz Centre for Environmental Research, Permoserstr. 15, 04318 Leipzig (Germany)

2011-10-15

Successful biodegradation of organic soil pollutants depends on their bioavailability to catabolically active microorganisms. In particular, environmental heterogeneities often limit bacterial access to pollutants. Experimental and modelling studies revealed that fungal networks can facilitate bacterial dispersal and may thereby improve pollutant bioavailability. Here, we investigate the influence of such bacterial dispersal networks on biodegradation performance under spatially heterogeneous abiotic conditions using a process-based simulation model. To match typical situations in polluted soils, two types of abiotic conditions are studied: heterogeneous bacterial dispersal conditions and heterogeneous initial resource distributions. The model predicts that networks facilitating bacterial dispersal can enhance biodegradation performance for a wide range of these conditions. Additionally, the time horizon over which this performance is assessed and the network's spatial configuration are key factors determining the degree of biodegradation improvement. Our results support the idea of stimulating the establishment of fungal mycelia for enhanced bioremediation of polluted soils. - Highlights: > Bacterial dispersal networks can considerably improve biodegradation performance. > They facilitate bacterial access to dispersal-limited areas and remote resources. > Abiotic conditions, time horizon and network structure govern the improvements. > Stimulating the establishment of fungal mycelia promises enhanced soil remediation. - Simulation modelling demonstrates that fungus-mediated bacterial dispersal can considerably improve the bioavailability of organic pollutants under spatially heterogeneous abiotic conditions typical for water-unsaturated soils.

Dispersion of Exhalation Pollutants in a Two-bed Hospital Ward with a Downward Ventilation System

DEFF Research Database (Denmark)

Qian, Hua; Nielsen, Peter V.; Hyldgård, Carl-Erik

2006-01-01

The Centers for Disease Control and Prevention has recommended the use of downward ventilation systems in isolation rooms to reduce the risk of cross-infection from airborne transmissible diseases. The expected airflow pattern of a downward ventilation design would supply cooler and slightly...... to investigate the airflow pattern and pollutant dispersion in the test ward. Based on both experimental and numerical results, the laminar airflow pattern was shown to be impossible to achieve due to turbulent flow mixing and flow entrainment into the supply air stream. The thermal plumes produced above people...... were found to induce flow mixing. We also studied the effects of the locations of the supply and extraction openings on both the flow pattern and pollutant exposure level in the occupied zone. A number of practical recommendations are suggested....

Turbulent Plume Dispersion over Two-dimensional Idealized Urban Street Canyons

Science.gov (United States)

Wong, C. C. C.; Liu, C. H.

2012-04-01

Human activities are the primary pollutant sources which degrade the living quality in the current era of dense and compact cities. A simple and reasonably accurate pollutant dispersion model is helpful to reduce pollutant concentrations in city or neighborhood scales by refining architectural design or urban planning. The conventional method to estimate the pollutant concentration from point/line sources is the Gaussian plume model using empirical dispersion coefficients. Its accuracy is pretty well for applying to rural areas. However, the dispersion coefficients only account for the atmospheric stability and streamwise distance that often overlook the roughness of urban surfaces. Large-scale buildings erected in urban areas significantly modify the surface roughness that in turn affects the pollutant transport in the urban canopy layer (UCL). We hypothesize that the aerodynamic resistance is another factor governing the dispersion coefficient in the UCL. This study is thus conceived to study the effects of urban roughness on pollutant dispersion coefficients and the plume behaviors. Large-eddy simulations (LESs) are carried out to examine the plume dispersion from a ground-level pollutant source over idealized 2D street canyons in neutral stratification. Computations with a wide range of aspect ratios (ARs), including skimming flow to isolated flow regimes, are conducted. The vertical profiles of pollutant distribution for different values of friction factor are compared that all reach a self-similar Gaussian shape. Preliminary results show that the pollutant dispersion is closely related to the friction factor. For relatively small roughness, the factors of dispersion coefficient vary linearly with the friction factor until the roughness is over a certain level. When the friction factor is large, its effect on the dispersion coefficient is less significant. Since the linear region covers at least one-third of the full range of friction factor in our empirical

A Fuel-Based Assessment of On-Road and Off-Road Mobile Source Emission Trends

Science.gov (United States)

Dallmann, T. R.; Harley, R. A.

2009-12-01

Mobile sources contribute significantly to emissions of nitrogen oxides (NOx) and fine particulate matter (PM2.5) in the United States. These emissions lead to a variety of environmental concerns including adverse human health effects and climate change. In the electric power sector, sulfur dioxide (SO2) and NOx emissions from power plants are measured directly using continuous emission monitoring systems. In contrast for mobile sources, statistical models are used to estimate average emissions from a very large and diverse population of engines. Despite much effort aimed at improving them, mobile source emission inventories continue to have large associated uncertainties. Alternate methods are needed to help evaluate estimates of mobile source emissions and quantify and reduce the associated uncertainties. In this study, a fuel-based approach is used to estimate emissions from mobile sources, including on-road and off-road gasoline and diesel engines. In this approach, engine activity is measured by fuel consumed (in contrast EPA mobile source emission models are based on vehicle km of travel and total amount of engine work output for on-road and off-road engines, respectively). Fuel consumption is defined in this study based on highway fuel tax reports for on-road engines, and from surveys of fuel wholesalers who sell tax-exempt diesel fuel for use in various off-road sectors such as agriculture, construction, and mining. Over the decade-long time period (1996-2006) that is the focus of the present study, national sales of taxable gasoline and diesel fuel intended for on-road use increased by 15 and 43%, respectively. Diesel fuel use by off-road equipment increased by about 20% over the same time period. Growth in fuel consumption offset some of the reductions in pollutant emission factors that occurred during this period. This study relies on in-use measurements of mobile source emission factors, for example from roadside and tunnel studies, remote sensing, and

Studies of self-pollution in diesel school buses: methodological issues.

Science.gov (United States)

Borak, Jonathan; Sirianni, Greg

2007-09-01

Considerable interest has focused on levels of exhaust emissions in the cabins of diesel-powered school buses and their possible adverse health effects. Significantly different policy and engineering issues would be raised if compelling evidence found that inc-cabin contamination was due to self-pollution from bus emissions, rather than ambient pollution, neighboring vehicles, and/or re-entrained road dust. We identified 19 reports from 11 studies that measured diesel exhaust particulate in the cabins of 58 school bus of various type. Studies were evaluated in light of their experimental design, their data quality, and their capacity to quantify self-pollution. Only one study had a true experimental design, comparing the same buses with and without emission controls, while four others used intentional tracers to quantify tail pipe and/or crankcase emissions. Although definitive data are still lacking, these studies suggest that currently available control technologies can nearly eliminate particulate self-pollution inside diesel school buses.

Experimental and numerical analysis of traffic emitted nanoparticle and particulate matter dispersion at urban pollution hot-spots

Science.gov (United States)

Goel, Anju

Road vehicles are a major source of airborne nanoparticles (traffic hot-spots such as traffic intersections (TIs), where pollution pockets are created due to frequently changing driving conditions. Recent trends suggest an exponential increase in travel demand and travelling time in the UK and elsewhere over the years, which indicate a growing need for the accurate characterisation of exposure at TIs since exposure at these hot-spots can contribute disproportionately high to overall commuting exposure. Based on field observations, this thesis aims (i) to investigate the traffic driving conditions in which TIs become a hotspot for nanoparticles and PM, (ii) to estimate the extent of road that is affected by high particle number concentrations (PNCs) and PM due to presence of a signal, (iii) to assess the vertical and horizontal variations in PNC and PMC at different TIs, (iv) to estimate the associated in-cabin and pedestrian exposure at TIs, and finally (v) to predict PNCs by using freely available models of air pollution at TIs. For this thesis, two sets of experiments (i.e. mobile- and fixed-sites) were carried out to measure airborne nanoparticles and PM in the size range of (0.005-10 ?m) using a fast response differential mobility spectrometer (DMS50) and a GRIMM particle spectrometer (1.107 E). Mobile measurements were made on a circle passing through 10 TIs and fixed-site measurements were carried out at two different types of TIs (i.e. 3- and 4-way). Dispersion modelling was then performed by using California Line Source (CALINE4) and California Line Source for Queueing and Hotspot Calculations (CAL3QHC) at TIs. Several important findings were then extrapolated during the analysis. These findings indicated that congested TIs were found to become hot-spots when vehicle accelerate from idling conditions. The average length of road in longitudinal direction that is affected by high PNCs and PM was found to be highest (148 m; 89 to -59 m from the center of a TI

Relationship between urbanisation and pollutant emissions in transboundary river basins under the strategy of the Belt and Road Initiative.

Science.gov (United States)

Yu, Sen; Lu, Hongwei

2018-07-01

Urbanisation has increased the discharge of pollutants, altered water flow regimes, and modified the morphology of transboundary river basins. All these actions have resulted in multiple pressures on aquatic ecosystems of transboundary river basins, undermining the healthy development of their aquatic ecosystems as well as impairing the sustainable economic and social development associated therewith. Quantifying the relationship between socio-economic factors, and water environment systems, and understanding the multiple pressures in their combined impact on environmental fairness of transboundary river basins is challenging, and it is crucial to the strategic planning of the Belt and Road strategy. Here, the Songhua River basin, which is the largest branch of the China-Russia boundary river is taken as the study area. The Environmental Kuznets Curve (EKC) model, which is coupled with the integrated model (pollutant emissions intensity, pollutant discharge efficiency, and pollutant emissions per capita), are used to reveal the spatio-temporal variations in regional pollutant emissions in the SRB. The results show that the features of the EKC are present in the pollutant emissions during economic development of the SRB. It also demonstrates that the turning point value of the EKC appeared when the GDP per capita is around ¥40,000 (CNY) in the SRB, which means that the pollutant emissions show an increasing trend, when the GDP per capita is less than ¥40,000. Our findings could contribute to a better understanding of the coupling relationship between pollutant emissions in transboundary river basins and urbanisation process in water stress to help address water allocation problems. Copyright © 2018 Elsevier Ltd. All rights reserved.

Seasonal comparison of moss bag technique against vertical snow samples for monitoring atmospheric pollution.

Science.gov (United States)

Salo, Hanna; Berisha, Anna-Kaisa; Mäkinen, Joni

2016-03-01

This is the first study seasonally applying Sphagnum papillosum moss bags and vertical snow samples for monitoring atmospheric pollution. Moss bags, exposed in January, were collected together with snow samples by early March 2012 near the Harjavalta Industrial Park in southwest Finland. Magnetic, chemical, scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDX), K-means clustering, and Tomlinson pollution load index (PLI) data showed parallel spatial trends of pollution dispersal for both materials. Results strengthen previous findings that concentrate and slag handling activities were important (dust) emission sources while the impact from Cu-Ni smelter's pipe remained secondary at closer distances. Statistically significant correlations existed between the variables of snow and moss bags. As a summary, both methods work well for sampling and are efficient pollutant accumulators. Moss bags can be used also in winter conditions and they provide more homogeneous and better controlled sampling method than snow samples. Copyright © 2015. Published by Elsevier B.V.

Carbon based secondary compounds do not provide protection against heavy metal road pollutants in epiphytic macrolichens.

Science.gov (United States)

Gauslaa, Yngvar; Yemets, Olena A; Asplund, Johan; Solhaug, Knut Asbjørn

2016-01-15

Lichens are useful monitoring organisms for heavy metal pollution. They are high in carbon based secondary compounds (CBSCs) among which some may chelate heavy metals and thus increase metal accumulation. This study quantifies CBSCs in four epiphytic lichens transplanted for 6months on stands along transects from a highway in southern Norway to search for relationships between concentrations of heavy metals and CBSCs along a gradient in heavy metal pollutants. Viability parameters and concentrations of 21 elements including nutrients and heavy metals in these lichen samples were reported in a separate paper. Medullary CBSCs in fruticose lichens (Ramalina farinacea, Usnea dasypoga) were reduced in the most polluted sites, but not in foliose ones (Parmelia sulcata, Lobaria pulmonaria), whereas cortical CBSC did not change with distance from the road in any species. Strong positive correlations only occurred between the major medullary compound stictic acid present in L. pulmonaria and most heavy metals, consistent with a chelating role of stictic acid, but not of other studied CBSCs or in other species. However, heavy metal chelating did not protect L. pulmonaria against damage because this species experienced the strongest reduction in viability in the polluted sites. CBSCs with an accumulation potential for heavy metals should be quantified in lichen biomonitoring studies of heavy metals because they, like stictic acid, could overshadow pollutant inputs in some species rendering biomonitoring data less useful. In the two fruticose lichen species, CBSCs decreased with increasing heavy metal concentration, probably because heavy metal exposure impaired secondary metabolism. Thus, we found no support for a heavy metal protection role of any CBSCs in studied epiphytic lichens. No intraspecific relationships occurred between CBSCs versus N or C/N-ratio. Interspecifically, medullary CBSCs decreased and cortical CBSCs increased with increasing C/N-ratio. Copyright © 2015

Study on the wind field and pollutant dispersion in street canyons using a stable numerical method.

Science.gov (United States)

Xia, Ji-Yang; Leung, Dennis Y C

2005-01-01

A stable finite element method for the time dependent Navier-Stokes equations was used for studying the wind flow and pollutant dispersion within street canyons. A three-step fractional method was used to solve the velocity field and the pressure field separately from the governing equations. The Streamline Upwind Petrov-Galerkin (SUPG) method was used to get stable numerical results. Numerical oscillation was minimized and satisfactory results can be obtained for flows at high Reynolds numbers. Simulating the flow over a square cylinder within a wide range of Reynolds numbers validates the wind field model. The Strouhal numbers obtained from the numerical simulation had a good agreement with those obtained from experiment. The wind field model developed in the present study is applied to simulate more complex flow phenomena in street canyons with two different building configurations. The results indicated that the flow at rooftop of buildings might not be assumed parallel to the ground as some numerical modelers did. A counter-clockwise rotating vortex may be found in street canyons with an inflow from the left to right. In addition, increasing building height can increase velocity fluctuations in the street canyon under certain circumstances, which facilitate pollutant dispersion. At high Reynolds numbers, the flow regimes in street canyons do not change with inflow velocity.

Exposures to road traffic, noise, and air pollution as risk factors for type 2 diabetes: A feasibility study in Bulgaria

Science.gov (United States)

Dzhambov, Angel M; Dimitrova, Donka D

2016-01-01

Type 2 diabetes mellitus (T2DM) is a growing public health problem in Bulgaria. While individual and lifestyle determinants have been researched; till date there has been no study on environmental risks such as road traffic, noise, and air pollution. As a first step toward designing a large-scale population-based survey, we aimed at exploring the overall associations of prevalent T2DM with exposures to road traffic, noise, and air pollution. A total of 513 residents of Plovdiv city, Bulgaria were recruited. Individual data on self-reported doctor-diagnosed T2DM and confounding factors were linked to objective and self-rated exposure indicators. Logistic and log-link Poisson regressions were conducted. In the fully adjusted logistic models, T2DM was positively associated with exposures to Lden 71-80 dB (odds ratio (OR) = 4.49, 95% confidence interval (CI): 1.38, 14.68), fine particulate matter (PM)2.5 25.0-66.8 μg/m3 (OR = 1.32, 95% CI: 0.28, 6.24), benzo alpha pyrene 6.0-14.02 ng/m3 (OR = 1.76, 95% CI: 0.52, 5.98) and high road traffic (OR = 1.40, 95% CI: 0.48, 4.07). Lden remained a significant risk factor in the: Poisson regression model. Other covariates with consistently high multivariate effects were age, gender, body mass index, family history of T2DM, subjective sleep disturbance, and especially bedroom location. We concluded that residential noise exposure might be associated with elevated risk of prevalent T2DM. The inferences made by this research and the lessons learned from its limitations could guide the designing of a longitudinal epidemiological survey in Bulgaria. PMID:27157686

Impacts of shape and height of upstream roof on airflow and pollutant dispersion inside an urban street canyon.

Science.gov (United States)

Huang, Yuan-Dong; He, Wen-Rong; Kim, Chang-Nyung

2015-02-01

A two-dimensional numerical model for simulating flow and pollutant dispersion in an urban street canyon is firstly developed using the FLUENT code and then validated against the wind tunnel results. After this, the flow field and pollutant dispersion inside an urban street canyon with aspect ratio W/H = 1 are examined numerically considering five different shapes (vaulted, trapezoidal, slanted, upward wedged, and downward wedged roofs) as well as three different roof height to building height ratios (Z H /H = 1/6, 1/3, and 1/2) for the upstream building roof. The results obtained reveal that the shape and height of an upstream roof have significant influences on flow pattern and pollutant distribution in an urban canyon. A large single clockwise vortex is generated in the canyon for the vaulted upstream roof at Z H /H = 1/6, 1/3, and 1/2, the trapezoidal and downward wedged roofs at Z H /H = 1/6 and 1/3, and the slanted and upward wedged roofs at Z H /H = 1/6, while a main clockwise vortex and a secondary counterclockwise vortex are established for the trapezoidal and downward wedged roofs at Z H /H = 1/2 and the slanted and upward wedged roofs at Z H /H = 1/3 and 1/2. In the one-vortex flow regime, the clockwise vortex moves upward and grows in size with increasing upstream roof height for the vaulted, trapezoidal, and downward wedged roofs. In the two-vortex flow regime, the size and rotational velocity of both upper clockwise and lower counterclockwise vortices increase with the upstream roof height for the slanted and upward wedged roofs. At Z H /H = 1/6, the pollution levels in the canyon are close among all the upstream roof shapes studied. At Z H /H = 1/3, the pollution levels in the canyon for the upward wedged roof and slanted roof are much higher than those for the vaulted, trapezoidal, and downward wedged roofs. At Z H /H = 1/2, the lowest pollution level appears in the canyon for the vaulted upstream roof, while

EnviroAtlas - Minneapolis/St. Paul, MN - Near Road Block Group Summary

Data.gov (United States)

U.S. Environmental Protection Agency — This EnviroAtlas dataset addresses the tree buffer along heavily traveled roads. The roads are interstates, arterials, and collectors within the EnviroAtlas...

Geochemical dispersion of uranium near prospects in Pennsylvania

International Nuclear Information System (INIS)

Rose, A.W.; Schmiermund, R.L.; Mahar, D.L.

1977-06-01

The geochemical dispersion of U was investigated near sedimentary uranium prospects in eastern and north-central Pennsylvania. Near Jim Thorpe, known uranium occurrences in the Catskill Fm. are limited to the base of the Duncannon member. At Penn Haven Junction, roll-type U deposits with appreciable Pb and Se are localized adjacent to an oxidized tongue of channel-filling conglomeratic sandstone. The channel and encircling U occurrences furnish a large target for geochemical exploration. Selective extractions show that the organic, Fe-oxide, sand and silt fractions of stream sediments are the major hosts for U in stream sediments. Fe-oxides have a greater affinity for U than organic matter but are less abundant. The U content of organic matter is about 10 5 times the U content of stream water. Stream sediments furnish a representative sample of the average content of U, Zn, Cu, and major elements in soils of a drainage basin in north-central Pennsylvania, so a semiquantitative appraisal of weathering uranium occurrences can be made from stream sediments in climates and topography like Pennsylvania. The flux of uranium leaving the basin in solution is about equal to that leaving as sediment. Uranium is considerably less mobile than Ca and Na. A new method of extracting uranium from water samples, using a liquid ion exchanger (Amberlite LA-1), shows promise for simple field application

Rapid identification of soil cadmium pollution risk at regional scale based on visible and near-infrared spectroscopy

NARCIS (Netherlands)

Chen, T.; Changa, Q.; Clevers, J.G.P.W.; Kooistra, L.

2015-01-01

Soil heavy metal pollution due to long-term sewage irrigation is a serious environmental problem in many irrigation areas in northern China. Quickly identifying its pollution status is an important basis for remediation. Visible-near-infrared reflectance spectroscopy (VNIRS) provides a useful tool.

Simulation of hypothetical Asian carp egg and larvae development and transport in the Lockport, Brandon Road, Dresden Island, and Marseilles Pools of the Illinois Waterway by use of the Fluvial Egg Drift Simulator (FluEgg) model

Science.gov (United States)

Murphy, Elizabeth A.; Garcia, Tatiana; Jackson, P. Ryan; Duncker, James J.

2016-04-05

As part of the Great Lakes and Mississippi River Interbasin Study, the U.S. Army Corps of Engineers (USACE) is conducting an assessment of the vulnerability of the Chicago Area Waterway System and Des Plaines River to Asian carp (specifically, Hypophthalmichthys nobilis (bighead carp) and Hypophthalmichthys molitrix (silver carp)) spawning and recruitment. As part of this assessment, the USACE requested the help of the U.S. Geological Survey in predicting the fate and transport of Asian carp eggs hypothetically spawned at the electric dispersal barrier on the Chicago Sanitary and Ship Canal and downstream of the Brandon Road Lock and Dam on the Des Plaines River under dry weather flow and high water temperature conditions. The Fluvial Egg Drift Simulator (FluEgg) model predicted that approximately 80 percent of silver carp eggs spawned near the electric dispersal barrier would hatch within the Lockport and Brandon Road pools (as close as 3.6 miles downstream of the barrier) and approximately 82 percent of the silver carp eggs spawned near the Brandon Road Dam would hatch in the Des Plaines River (as close as 1.6 miles downstream from the gates of Brandon Road Lock). Extension of the FluEgg model to include the fate and transport of larvae until gas bladder inflation—the point at which the larvae begin to leave the drift—suggests that eggs spawned at the electric dispersal barrier would reach the gas bladder inflation stage primarily within the Dresden Island Pool, and those spawned at the Brandon Road Dam would reach this stage primarily within the Marseilles and Starved Rock Pools.

Modelling of pollution dispersion in atmosphere

International Nuclear Information System (INIS)

Borysiewicz, M.; Stankiewicz, R.

1994-01-01

The paper contains the review of the mathematical foundation of atmospheric dispersion models. The atmospheric phenomena relevant to atmospheric dispersion model are discussed. In particular the parametrization of processes with time and space scales smaller than numerical grid size, limited by available computer power, is presented. The special attention was devoted to similarity theory and parametrization of boundary layer. The numerical methods are analysed and the drawbacks of the method are presented. (author). 99 refs, 15 figs, 3 tabs

Treatment Solutions for Rainwater Contaminated with Various Pollutants

Directory of Open Access Journals (Sweden)

Adriana Tokar

2015-07-01

Full Text Available This study presents aspects on the environmental pollution with contaminants difficult to manage from sources such as car parking, roads and roofs in crowded areas that have deficient wastewater harvesting urban networks. The contaminants washed by the rainwater that are not collected and treated can reach directly into the natural environment. Thus, rainwater which falls on rough surfaces, especially in car parking and roads without drainage channels carries out various pollutants directly into the soil and water. In order to control environmental pollution there are presented solutions for contaminated rainwater depollution.