Investigating the concentration levels, distribution patterns, source identification and health risk assessment of PAHs, n-alkanes, hopanes, and steranes in deposited dust of Mashhad, Iran

Abstract Deposited dust (DD) in urban environments contains carcinogenic organic compounds. The Indoor air quality is greatly affected by heating, ventilation, and air conditioning systems (HVAC), and in the Middle East most of the buildings are equipped by HVAC on top of them. It is possible that the DD on the roof near this equipment would be transferred to an indoor area. For these reasons, 40 samples of the over the roof DD were prepared, and organic compounds (16PAH compounds, 20n-alkane homologs, 8hopanes, and 6steranes) of DD were extracted using Soxhlet and analyzed by GC-MS. Source identification of organic compounds conducted by ring classification, diagnostic ratios, and factor analysis (FA). The results showed that the average (±SD) of total PAHs, n-alkanes, hopanes and steranes in DD were 1356.00 (±291.45) ng kg−1dw, 3211.65 (±969.18), 146.37 (±79.45) and 469.76 (±188.25) µg.g_1dw, respectively. The highest concentration of organic compounds was in the city center, where traffic congestion is common. Diagnostic ratios of n-alkanes results showed the dominant source is vehicular emission. FA results indicated vehicular emission and biogenic sources. In agreement, the results of sterane and hopane profiles confirm these results. On the other hand, the PAHs diagnostic ratios results indicated petroleum combustion sources. In this regard, FA findings showed combustion from vehicular emission and natural gas and wood combustion were the main factors. Furthermore, the incremental lifetime cancer risk was calculated as 8.45× 10−12 for children and 9.80 × 10−7 for adults, and the imposed risk was negligible.

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Spatial distribution, source identification, and risk assessment of organochlorines in wild tilapia from Guangxi, South China

Scientific Reports ◽

10.1038/s41598-020-72160-x ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Yang Ding ◽

Zhiqiang Wu ◽

Ruijie Zhang ◽

Yaru Kang ◽

Kefu Yu ◽

...

Keyword(s):

Risk Assessment ◽

Spatial Distribution ◽

Cancer Risk ◽

South China ◽

Lipid Content ◽

Source Identification ◽

Diagnostic Ratios ◽

Guangxi Province ◽

Feeding Intensity ◽

Lifetime Cancer Risk

Abstract Seventy-five wild tilapia samples from six rivers (ten sites) in Guangxi province were collected and analyzed for 53 organochlorine compounds. DDTs, endosulfan, and PCBs were the most dominant compounds found in this study. Tiandong County (TD) and Guigang City (GG) sites were found to be heavily contaminated with high levels of endosulfan (385–925 ng/g lw) and/or DDTs (20.1–422 ng/g lw). The diagnostic ratios indicated that the residues of DDTs and endosulfan in wild tilapia are associated with historical applications as well as the recent introduction of technical DDTs and endosulfan at some sampling sites. The correlation between total length, body mass, and organochlorines (OCs) was higher than the correlation between age and lipid content. There was no significant correlation between organochlorine pesticides (OCPs) and lipid content. Therefore, for organisms, the feeding intensity (related to length and mass) of fish could better reflect degree of pollution than exposure time (age) of fish. The hazardous ratios for the 50th and 95th percentile data of OCPs and PCBs in fish were both below 1, suggesting that daily exposure to OCPs and PCBs yields a lifetime cancer risk lower than 1 in 10,000.

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An Efficient Information Services-Centric Framework for Commuter

International Journal of Information Systems in the Service Sector ◽

10.4018/jisss.2012010102 ◽

2012 ◽

Vol 4 (1) ◽

pp. 22-39

Author(s):

Wee Siong Ng ◽

Justin Cheng ◽

XianJun Wang ◽

Sivakumar Viswanathan

Keyword(s):

Mobile Devices ◽

Traffic Congestion ◽

Traffic Management ◽

Spatial Information ◽

Urban Environments ◽

Mobile Environment ◽

Real Time Traffic ◽

Efficient Information ◽

Matching Mechanism ◽

Information Consumers

One of the major objectives of Advanced Traffic Management Systems (ATMS) is to reduce traffic congestion in urban environments by improving the efficiency of utilization of existing transport infrastructures. Many creative and efficient technologies have been developed over the years. Although commuters, especially drivers, take a critical part in containing traffic congestion problems, they are playing a passive role in the traffic-management ecosystem. Considerably, this is due to the information asymmetry between ATMS decision makers and commuters; what is missing is a matching mechanism to create a bridge between information providers and information consumers in the mobile environment. The authors’ solution provides an efficient services-centric framework for delivering pertinent information to commuters. Probe vehicles are used to estimate the real-time traffic flow and disseminate this information effectively to users’ mobile devices. A 2-level indexing scheme is designed to effectively index the grid cells which contain the spatial information and a location-aware mobile application and back-end services are also implemented. Processed information is disseminated to users’ mobile devices through wireless means and presented in a user friendly interface. Experimental results show that this system is scalable and responsive.

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Excess Lifetime Cancer Risk Assessment of Volatile Organic Compounds Emitted from a Petrochemical Industrial Complex

Aerosol and Air Quality Research ◽

10.4209/aaqr.2015.05.0372 ◽

2016 ◽

Vol 16 (8) ◽

pp. 1954-1966 ◽

Cited By ~ 9

Author(s):

Ming-Jen Chen ◽

Ching-Ho Lin ◽

Chin-Hsing Lai ◽

Li-Hsin Cheng ◽

Ya-Hui Yang ◽

...

Keyword(s):

Risk Assessment ◽

Volatile Organic Compounds ◽

Cancer Risk ◽

Organic Compounds ◽

Cancer Risk Assessment ◽

Industrial Complex ◽

Lifetime Cancer Risk ◽

Excess Lifetime Cancer Risk ◽

Volatile Organic

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Assessment of Impacts Produced by Anthropogenic Sources in a Little City near an Important Industrial Area (Modugno, Southern Italy)

The Scientific World JOURNAL ◽

10.1155/2013/150397 ◽

2013 ◽

Vol 2013 ◽

pp. 1-10 ◽

Cited By ~ 4

Author(s):

Martino Amodio ◽

Gianluigi de Gennaro ◽

Annalisa Marzocca ◽

Livia Trizio ◽

Maria Tutino

Keyword(s):

Cancer Risk ◽

Southern Italy ◽

Industrial Area ◽

Anthropogenic Sources ◽

Traffic Density ◽

Diagnostic Ratios ◽

Vehicular Traffic ◽

Lifetime Cancer Risk ◽

Benzene Toluene ◽

The City

An annual monitoring campaign of VOCs, consisting of twelve sampling periods, was carried out from June 2008 to June 2009 in Modugno, a city located in the Apulia region (Southern Italy), in order to assess the urban air quality, identify the main emission sources, and quantify the cancer and no-cancer risk attributable to inhalation exposures. Monitoring, carried out by using the Radiello diffusive samplers, was conducted in eleven sampling sites throughout the city taking into account the traffic density and the architecture of the city. From the study of the data, it was found that, among all considered VOCs, benzene, toluene, ethylbenzene, and xylenes (BTEX) are the pollutants at higher concentration. The analysis of VOC concentrations, the study of the topography of the city, and the use of different diagnostic ratios between the BTEX species showed that the vehicular traffic emissions were the predominant source of VOCs in the urban area of Modugno. Despite that the annual concentration of benzene is lower than the regulatory limit, the estimation of cancer risk showed that the global lifetime cancer risk attributed to the investigated VOC exposure was not negligible and therefore should be taken into account in future regulatory approaches.

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Comprehensive organic emission profiles for gasoline, diesel, and gas-turbine engines including intermediate and semi-volatile organic compound emissions

Atmospheric Chemistry and Physics ◽

10.5194/acp-18-17637-2018 ◽

2018 ◽

Vol 18 (23) ◽

pp. 17637-17654 ◽

Cited By ~ 17

Author(s):

Quanyang Lu ◽

Yunliang Zhao ◽

Allen L. Robinson

Keyword(s):

Volatile Organic Compounds ◽

Gas Turbine ◽

Organic Compounds ◽

Cold Start ◽

Urban Environments ◽

Particulate Filter ◽

Published Data ◽

Source Profiles ◽

Volatile Organic ◽

Unburned Fuel

Abstract. Emissions from mobile sources are important contributors to both primary and secondary organic aerosols (POA and SOA) in urban environments. We compiled recently published data to create comprehensive model-ready organic emission profiles for on- and off-road gasoline, gas-turbine, and diesel engines. The profiles span the entire volatility range, including volatile organic compounds (VOCs, effective saturation concentration C*=107–1011 µg m−3), intermediate-volatile organic compounds (IVOCs, C*=103–106 µg m−3), semi-volatile organic compounds (SVOCs, C*=1–102 µg m−3), low-volatile organic compounds (LVOCs, C*≤0.1 µg m−3) and non-volatile organic compounds (NVOCs). Although our profiles are comprehensive, this paper focuses on the IVOC and SVOC fractions to improve predictions of SOA formation. Organic emissions from all three source categories feature tri-modal volatility distributions (“by-product” mode, “fuel” mode, and “lubricant oil” mode). Despite wide variations in emission factors for total organics, the mass fractions of IVOCs and SVOCs are relatively consistent across sources using the same fuel type, for example, contributing 4.5 % (2.4 %–9.6 % as 10th to 90th percentiles) and 1.1 % (0.4 %–3.6 %) for a diverse fleet of light duty gasoline vehicles tested over the cold-start unified cycle, respectively. This consistency indicates that a limited number of profiles are needed to construct emissions inventories. We define five distinct profiles: (i) cold-start and off-road gasoline, (ii) hot-operation gasoline, (iii) gas-turbine, (iv) traditional diesel and (v) diesel-particulate-filter equipped diesel. These profiles are designed to be directly implemented into chemical transport models and inventories. We compare emissions to unburned fuel; gasoline and gas-turbine emissions are enriched in IVOCs relative to unburned fuel. The new profiles predict that IVOCs and SVOC vapour will contribute significantly to SOA production. We compare our new profiles to traditional source profiles and various scaling approaches used previously to estimate IVOC emissions. These comparisons reveal large errors in these different approaches, ranging from failure to account for IVOC emissions (traditional source profiles) to assuming source-invariant scaling ratios (most IVOC scaling approaches).

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System Dynamics Analysis of the Relationship between Transit Metropolis Construction and Sustainable Development of Urban Transportation—Case Study of Nanchang City, China

Sustainability ◽

10.3390/su12073028 ◽

2020 ◽

Vol 12 (7) ◽

pp. 3028

Author(s):

Yunqiang Xue ◽

Lin Cheng ◽

Kuang Wang ◽

Jing An ◽

Hongzhi Guan

Keyword(s):

Sustainable Development ◽

System Dynamics ◽

Traffic Congestion ◽

Simulation Analysis ◽

Supply And Demand ◽

Urban Transportation ◽

Urban Environments ◽

Motor Vehicles ◽

The Sustainable Development ◽

New Energy

In order to systematically analyze the benefits of transit metropolis construction, the system dynamics (SD) theory was used to construct the transit metropolis SD simulation model from the four subsystems of economy, society, environment, and transportation supply and demand. The validity of the SD model was verified by the social and economic data of Nanchang City and the operational data of the bus company, and the quantitative simulation analysis was carried out by taking the construction of the transit metropolis in Nanchang as an example. The simulation results show that, in 2020, the number of motor vehicles in Nanchang will reach 1.13 million and the urban population will reach 5.71 million. It is necessary to build a transit metropolis for the sustainable development of urban transportation. In order to complete the transit metropolis creation goal of 60% of the public transit mobility sharing rate, the proportion of public transport investment in the total transportation investment needs to be adjusted from 0.25 to 0.35. As a result, Nanchang City will improve after the peak traffic congestion in 2022, indicating that the construction of the transit metropolis will have a positive effect on Nanchang. By developing new energy vehicles and low-emission vehicles, vehicle emissions will drop from 0.05 tons/year to 0.04 tons/year, and overall nitrogen oxide emissions will fall by 70%, which is significant for urban environments. The research results provide theoretical support for the significance of transit metropolis construction, and promote the sustainable development of urban transportation.

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Evaluation of a Passive Sampling Method for Long-Term Continuous Monitoring of Volatile Organic Compounds in Urban Environments

Environmental Science & Technology ◽

10.1021/acs.est.8b02792 ◽

2018 ◽

Vol 52 (18) ◽

pp. 10580-10589 ◽

Cited By ~ 1

Author(s):

Robert M. Healy ◽

Julie Bennett ◽

Jonathan M. Wang ◽

Nicholas S. Karellas ◽

Colman Wong ◽

...

Keyword(s):

Volatile Organic Compounds ◽

Organic Compounds ◽

Continuous Monitoring ◽

Passive Sampling ◽

Sampling Method ◽

Urban Environments ◽

Volatile Organic

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Sources of black carbon at residential and traffic environments

10.5194/acp-2021-231 ◽

2021 ◽

Author(s):

Sanna Saarikoski ◽

Jarkko V. Niemi ◽

Minna Aurela ◽

Liisa Pirjola ◽

Anu Kousa ◽

...

Keyword(s):

Black Carbon ◽

Source Apportionment ◽

Urban Areas ◽

Street Canyon ◽

Current Knowledge ◽

Large Fraction ◽

Urban Environments ◽

Biomass Combustion ◽

Wood Combustion ◽

Aerosol Mass

Abstract. This study investigated the sources of black carbon (BC) at two contrasting urban environments in Helsinki, Finland; residential area and street canyon. The sources of BC were explored by using positive matrix factorization (PMF) for the organic and refractory black carbon (rBC) mass spectra collected with a soot particle aerosol mass spectrometer (SP-AMS). Two sites had different local BC sources; the largest fraction of BC originated from biomass burning at the residential site (38 %) and from the vehicular emissions at the street canyon (57 %). Also, the mass size distribution of BC diverged at the sites as BC from traffic was found at the particle size of ~100–150 nm whereas BC from biomass combustion was detected at ~300 nm. At both sites, a large fraction of BC was associated with urban background or long-range transported BC indicated by the high oxidation state of organics related to those PMF factors. The results from the PMF analysis were compared with the source apportionment from the aethalometer model calculated with two pair of absorption Ångström values. It was found that several PMF factors can be attributed to wood combustion and fossil fuel fraction of BC provided by the aethalometer model. In general, the aethalometer model showed less variation between the sources within a day than PMF being less responsive to the fast changes in the BC sources at the site. The results of this study increase understanding of the limitations and validity of the BC source apportionment methods in different environments. Moreover, this study advances the current knowledge of BC sources and especially the contribution of residential combustion in urban areas.

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