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Estimation of the emissions by transport in two port cities of the northeastern Mediterranean, Greece
2020
Fameli, K.M. | Kotrikla, A.M. | Psanis, C. | Biskos, G. | Polydoropoulou, A.
Air pollution is one of the most important branches of environmental science as it affects human health, climate and ecosystems. Emissions of air pollutants from transport (vehicles and ships) in port cities strongly affect air quality at local scales, warranting for a combination of theoretical and experimental studies to identify pollution hotspots. The purpose of this paper is to provide a methodology for developing a hybrid emission inventory from transport sector for two port cities located respectively on the Northern Aegean islands of Chios and Lesvos. Emission inventories were constructed for the year 2014 based on top-down and bottom-up approaches. Official data from local authorities and survey results were used for the calculation of emissions. Traffic emissions were spatially allocated to the road network based on population data and hourly traffic counts, and distributed over time (on an hourly basis) with the use of local temporal coefficients.Regarding carbon monoxide road emissions, the highest quantities are mainly emitted by Passenger Cars (43%,32% in Chios and Lesvos respectively) while for PM₁₀ emissions, trucks have the largest share (66% in Chios and 86% in Lesvos). The pollutants that are emitted in greater quantities from the ships at the ports of Mytilene and Chios are NOₓ, followed by SO₂ and CO. Most of the ship emissions in the ports occur by the ships at berth, as they remain berthed for hours whereas maneuvering lasts 15–20 min. As for the daily contribution of the two transport sources to the pollution profile of Mytilene, road emissions are higher for almost all pollutants. However, the contribution of ship emissions is not negligible, especially during the touristic period when marine traffic increases and emissions close to the port area become more important than those from road transport.
Show more [+] Less [-]On-road emission measurements of reactive nitrogen compounds from heavy-duty diesel trucks in China
2020
He, Liqiang | Zhang, Shaojun | Hu, Jingnan | Li, Zhenhua | Zheng, Xuan | Cao, Yihuan | Xu, Guangyi | Yan, Min | Wu, Ye
Emissions of major reactive nitrogen compounds, including nitric oxide (NO), nitrogen dioxide (NO₂) and ammonia (NH₃), from heavy-duty diesel vehicles (HDDVs) place substantial pressure on air quality for many large cities in China. To control nitrogen oxide (NOX) emissions from HDDVs, selective catalytic reduction (SCR) systems have been widely used since the China IV standards. To investigate the impacts of aftertreatment technologies and driving conditions on real-world emissions of reactive nitrogen compounds, a portable emissions measurement system was employed to test eighteen heavy-duty diesel trucks in China. The results showed that the China IV and China V HDDVs with appropriate SCR functionality could reduce NOX emissions by 36% and 53%, respectively, compared to the China III results, although their real-world emissions were still higher than the corresponding emission limits for regulatory engine tests. For these HDDVs, five samples were tested with NH₃ emissions, ranging from 1.67 ppm to 51.49 ppm. The NH₃ emission rates tended to significantly increase under high-speed driving conditions. The results indicate that the current SCR technology may have certain risks in exceeding the future China VI NH₃ limit. However, five China IV/V HDDVs were found to have SCR temperature sensors that were intentionally tampered with, resulting in comparable or even higher NOX emissions and zero NH₃ emissions. Increased NO₂ emissions due to the adoption of diesel oxidation catalysts and diesel particulate filters were also found from our experiments. This study highlights the importance of enhancing in-use compliance requirements and eliminating aftertreatment tampering for China IV and China V HDDVs.
Show more [+] Less [-]Hotspots of black carbon and PM2.5 in an urban area and relationships to traffic characteristics
2016
Targino, Admir Créso | Gibson, Mark David | Krecl, Patricia | Rodrigues, Marcos Vinicius Costa | dos Santos, Maurício Moreira | de Paula Corrêa, Marcelo
Three instrumented bicycles were used to measure black carbon (BC) and PM2.5 concentrations in a midsized city in southern Brazil. The objective of this study was to map the spatial distribution of BC and PM2.5, to identify air pollution hotspots and to assess factors that may affect the concentrations of these pollutants, e.g. traffic volume, number of heavy-duty diesel vehicles (HDDV), position of traffic signals and street incline. The cyclists collected data in the city centre along streets of different traffic density during nine sampling sessions in the weekday morning and afternoon rush hours, between March 13 and April 28, 2015. The sampling by bicycle covered an area of 2.70 km2, over variable elevation, and travelled a total distance of 215 km. BC and PM2.5 exhibited a large spatial variability on a scale of tens of metres and the concentrations were positively correlated with traffic counts, but exhibited a stronger relationship with the number of HDDV. These results imply that older buses and diesel-powered trucks may be the main driver behind the high pollution levels in the city's inner core. We observed a strong relationship between BC concentrations at junctions managed by traffic signals and the quantity of HDDV. The mean BC concentration was found to be 8.10 μg m−3 near traffic signals located on an inclined street (HDDV > 100 vehicles h−1) compared to traffic signals on flat terrain (6.00 μg m−3), which can be attributed to the higher acceleration required at the start of motion. This pattern was less evident for PM2.5 concentrations.
Show more [+] Less [-]Assessment of vehicle emission programs in China during 1998–2013: Achievement, challenges and implications
2016
Wu, Xiaomeng | Wu, Ye | Zhang, Shaojun | Liu, Huan | Fu, Lixin | Hao, Jiming
China has been embracing rapid motorization since the 1990s, and vehicles have become one of the major sources of air pollution problems. Since the late 1990s, thanks to the international experience, China has adopted comprehensive control measures to mitigate vehicle emissions. This study employs a local emission model (EMBEV) to assess China's first fifteen-year (1998–2013) efforts in controlling vehicles emissions. Our results show that China's total annual vehicle emissions in 2013 were 4.16 million tons (Mt) of HC, 27.4 Mt of CO, 7.72 Mt of NOX, and 0.37 Mt of PM2.5, respectively. Although vehicle emissions are substantially reduced relative to the without control scenarios, we still observe significantly higher emission density in East China than in developed countries with longer histories of vehicle emission control. This study further informs China's policy-makers of the prominent challenges to control vehicle emissions in the future. First, unlike other major air pollutants, total NOX emissions have rapidly increased due to a surge of diesel trucks and the postponed China IV standard nationwide. Simultaneous implementation of fuel quality improvements and vehicle-engine emission standards will be of great importance to alleviate NOX emissions for diesel fleets. Second, the enforcement of increasingly stringent standards should include strict oversight of type-approval conformity, in-use complacence and durability, which would help reduce gross emitters of PM2.5 that are considerable among in-use diesel fleets at the present. Third, this study reveals higher HC emissions than previous results and indicates evaporative emissions may have been underestimated. Considering that China's overall vehicle ownership is far from saturation, persistent efforts are required through economic tools, traffic management and emissions regulations to lower vehicle-use intensity and limit both exhaust and evaporative emissions. Furthermore, in light of the complex technology for emerging new energy vehicles, their real-world emissions need to be adequately evaluated before massive promotion.
Show more [+] Less [-]Manganese concentrations in drinking water from villages near banana plantations with aerial mancozeb spraying in Costa Rica: Results from the Infants' Environmental Health Study (ISA)
2016
van Wendel de Joode, Berna | Barbeau, Benoit | Bouchard, Maryse F. | Mora, Ana María | Skytt, Åsa | Córdoba, Leonel | Quesada, Rosario | Lundh, Thomas | Lindh, Christian H. | Mergler, Donna
Elevated manganese (Mn) in drinking water has been reported worldwide. While, naturally occurring Mn in groundwater is generally the major source, anthropogenic contamination by Mn-containing fungicides such as mancozeb may also occur. The main objective of this study was to examine factors associated with Mn and ethylenethiourea (ETU), a degradation product of mancozeb, in drinking water samples from villages situated near banana plantations with aerial spraying of mancozeb. Drinking water samples (n = 126) were obtained from 124 homes of women participating in the Infants' Environmental Health Study (ISA, for its acronym in Spanish), living nearby large-scale banana plantations. Concentrations of Mn, iron (Fe), arsenic (As), lead (Pb), cadmium (Cd) and ethylenethiourea (ETU), a degradation product of mancozeb, were measured in water samples. Only six percent of samples had detectable ETU concentrations (limit of detection (LOD) = 0.15 μg/L), whereas 94% of the samples had detectable Mn (LOD = 0.05 μg/L). Mn concentrations were higher than 100 and 500 μg/L in 22% and 7% of the samples, respectively. Mn was highest in samples from private and banana farm wells. Distance from a banana plantation was inversely associated with Mn concentrations, with a 61.5% decrease (95% CI: −97.0, −26.0) in Mn concentrations for each km increase in distance. Mn concentrations in water transported with trucks from one village to another were almost 1000 times higher than Mn in water obtained from taps in houses supplied by the same well but not transported, indicating environmental Mn contamination. Elevated Mn in drinking water may be partly explained by aerial spraying of mancozeb; however, naturally occurring Mn in groundwater, and intensive agriculture may also contribute. Drinking water risk assessment for mancozeb should consider Mn as a health hazard. The findings of this study evidence the need for health-based World Health Organization (WHO) guidelines on Mn in drinking water.
Show more [+] Less [-]The exposure of pedestrians, drivers and road transport passengers to nitrogen dioxide
2016
Żak, Magdalena | Melaniuk-Wolny, Edyta | Widziewicz, Kamila
People travelling by road transport are exposed to high levels of nitrogen oxides (NOx), that are considered to be one of the primary pollutants from motor vehicles. This study examines the exposure of drivers, passengers and pedestrians to NO2 during different trip scenarios: travelling by private or public means of transport, along the major commuter routes in one of the biggest Polish agglomerations - Silesia Agglomeration, and other important communication routes in Poland, as well as during walks in both city centers and residential areas. The NO2 samples were collected in cars, trucks and buses interiors, as well as in the ambient air by passive samplers and next NO2 concentrations were analyzed by means of the spectrophotometric technique. The obtained results indicate that travelling by cars through city centers is associated with the exposure to NO2 concentrations of about 15% higher than in the case of travelling suburban routes; 33% greater than travelling by bus in urban traffic; more than app. 60% higher than in the case of travelling by bus in suburban traffic or by foot in city centers and up to 80% higher than moving on foot near little-used roads. The exposure profile of six groups of road users exposed to NO2 was therefore determined in this study. The obtained results could be used by policy makers to minimize the exposure to transportation-related pollutants concentrations and for planning far-reaching changes in the field of urban road transport.
Show more [+] Less [-]The Influence of Phosphate Mining on the Chemical Composition of Annual Atmospheric Deposition in Catalão (GO) and Tapira (MG), Brazil
2016
da Conceição, Fabiano Tomazini | Litholdo, Taise | de Souza Sardinha, Diego | Moruzzi, Rodrigo Braga | Navarro, Guillermo Rafael Beltran | Godoy, Letícia Hirata
Brazil is an important country within the global mineral industry. The main reserves of phosphate rock in Brazil are contained in the states of Goiás and Minas Gerais, at the Catalão and Tapira cities, respectively. Atmospheric inputs due to the mining of phosphate rock may have various effects on human health in areas near these types of mines. Thus, this work evaluated the influence of phosphate mining on the chemical composition and annual atmospheric deposition in Catalão (GO) and Tapira (MG), Brazil. The pH of rainwater was 6.90 in Catalão and 6.80 in Tapira. The ionic concentrations (in μeq/L) at both study sites decreased in the following order: Ca²⁺ > Na⁺ > Mg²⁺ > K⁺ for cations and HCO₃ ⁻ > NO₃ ⁻ > SO₄ ²⁻ > PO₄ ³⁻ > F⁻ > Cl⁻ for anions. High Ca²⁺ content indicates that Ca²⁺ contributes to the neutralisation of the rainwater pH in both of the areas studied. The annual atmospheric deposition of NO₃ ⁻ and SO₄ ²⁻ can be attributed to the use of diesel-powered trucks in and around mining areas. Soil dust derived is responsible for the annual atmospheric deposition of Na⁺ and K⁺. Phosphate mining activities are the main source of the annual atmospheric deposition of PO₄ ³⁻ and F⁻.
Show more [+] Less [-]Uncovering Pakistan’s Environmental Risks and Remedies under the China-Pakistan Economic Corridor
2020
Kouser, Shahzad | Subhan, Abdul | Abedullah,
The China-Pakistan Economic Corridor (CPEC) is a journey towards economic integration of Eurasia. The CPEC contains US$62 billion investment projects on energy, infrastructure, and other development projects in Pakistan. However, CPEC could enhance climate change vulnerabilities for the faltering economy of Pakistan due to its three possible environmental risks and repercussions. Its major environmental concern is related to energy projects as three quarters of the newly planned energy will be generated from traditional coal-fired power plants. Traditional coal power plants are the major contributors to CO₂ emissions and smog, which ultimately lead to global warming and climate change. Its second important environmental concern is linked with massive tree cutting for the construction of various road networks from Kashghar, China, to Gwadar, Pakistan. Tree cutting leads to enormous concentration of CO₂ emissions along the road networks. Vehicle trafficking is its third important environmental threat. Karakorum highway is expected to carry up to 7000 trucks per day that will release up to 36.5 million tons of CO₂. Despite all the environmental risks, the CPEC enables Pakistan to manage energy crisis and upgrade aging infrastructure. However, if appropriate remedial measures are not taken to diminish environmental risks, Pakistan will be among major contributors to CO₂ emissions, and its rank will be worsen in global climate risk index, after completion of this project. Therefore, it is very crucial to assess possible environmental impacts of CPEC projects regarding energy, infrastructure, and transportation. Furthermore, scientists from both countries should collaborate to manage the environmental repercussions of CPEC projects.
Show more [+] Less [-]Chemical and microbial characteristics of municipal drinking water supply systems in the Canadian Arctic
2018
Daley, Kiley | Truelstrup Hansen, Lisbeth | Jamieson, Rob C. | Hayward, Jenny L. | Piorkowski, Greg S. | Krkosek, Wendy | Gagnon, Graham A. | Castleden, Heather | MacNeil, Kristen | Poltarowicz, Joanna | Corriveau, Emmalina | Jackson, Amy | Lywood, Justine | Huang, Yannan
Drinking water in the vast Arctic Canadian territory of Nunavut is sourced from surface water lakes or rivers and transferred to man-made or natural reservoirs. The raw water is at a minimum treated by chlorination and distributed to customers either by trucks delivering to a water storage tank inside buildings or through a piped distribution system. The objective of this study was to characterize the chemical and microbial drinking water quality from source to tap in three hamlets (Coral Harbour, Pond Inlet and Pangnirtung—each has a population of <2000) on trucked service, and in Iqaluit (population ~6700), which uses a combination of trucked and piped water conveyance. Generally, the source and drinking water was of satisfactory microbial quality, containing Escherichia coli levels of <1 MPN/100 mL with a few exceptions, and selected pathogenic bacteria and parasites were below detection limits using quantitative polymerase chain reaction (qPCR) methods. Tap water in households receiving trucked water contained less than the recommended 0.2 mg/L of free chlorine, while piped drinking water in Iqaluit complied with Health Canada guidelines for residual chlorine (i.e. >0.2 mg/L free chlorine). Some buildings in the four communities contained manganese (Mn), copper (Cu), iron (Fe) and/or lead (Pb) concentrations above Health Canada guideline values for the aesthetic (Mn, Cu and Fe) and health (Pb) objectives. Corrosion of components of the drinking water distribution system (household storage tanks, premise plumbing) could be contributing to Pb, Cu and Fe levels, as the source water in three of the four communities had low alkalinity. The results point to the need for robust disinfection, which may include secondary disinfection or point-of-use disinfection, to prevent microbial risks in drinking water tanks in buildings and ultimately at the tap.
Show more [+] Less [-]PM2.5 emissions from different types of heavy-duty truck: a case study and meta-analysis of the Beijing-Tianjin-Hebei region
2017
Song, Liying | Song, Hongqing | Lin, Jingyi | Wang, Cheng | Yu, Mingxu | Huang, Xiaoxia | Guan, Yu | Wang, Xing | Du, Li
Beijing-Tianjin-Hebei (BTH) region in China is affected seriously by the hazy weather that has a large impact on human health. PM₂.₅ is one of the most important reasons for hazy weather. Understanding the PM₂.₅ emission characteristics from different types of heavy-duty trucks (HDTs) is valuable in policies and regulations to improve urban air quality and mitigate vehicle emission in China. The investigation and analysis on HDT population and PM₂.₅ emission in BTH region are carried out. The results show that the population and PM₂.₅ emission of HDTs in BTH has risen for the last four consecutive years, from 404 thousand and 1795 tons in 2012 to 551 thousand and 2303 tons in 2015. The PM₂.₅ emission from HDTs in Hebei is about 10 times more than that of Beijing and 9 times more than that of Tianjin. The proportion of natural gas HDTs is about 5%; however, its PM₂.₅ emission only accounts for 0.94% in 2015, which indicates the utilization of HDTs powered by natural gas facilitate PM₂.₅ mitigation more than diesel in BTH. The tractor and pickup trucks are the main source of PM₂.₅ emission from different types of HDT, while special and dump trucks are relatively clean. This study has provided insights for management method and policy-making of vehicle in terms of environmental demand.
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