Ammonia (NH) plays an important role in the formation of atmospheric particulate matter, but the contribution of traffic-related emissions remains unclear, particularly in megacities with a large number of vehicles. Taking the opportunity of the stringent COVID-19 lockdowns implemented in Beijing and Shanghai in 2022, this study aims to estimate the traffic-related NH emissions in these two megacities based on satellite observations. Differences between urban and suburban areas during the lockdown and non-lockdown periods are compared. It was found that despite different dominating sources, the overall NH concentrations in urban and suburban areas were at a similar level, and the lockdown resulted in a more prominent decrease in urban areas, where traffic activities were most heavily affected. The traffic-related contribution to the total emission was estimated to be ∼30% in megacities, and ∼40% in urban areas, which are about 2-10 times higher than that in previous studies. The findings indicate that the traffic-related NH emissions have been significantly underestimated in previous studies and may play a more critical role in the formation of air pollution in megacities, especially in winter, when agricultural emissions are relatively low. This study highlights the importance of traffic-related NH emissions in Chinese megacities and the need to reassess the emissions and their impacts on air quality.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1016/j.chemosphere.2024.142497 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Concentrations and origins of ultrafine particles at a major European harbor.
Sci Total Environ
January 2025
Institute of Environmental Assessment and Water Research, Spanish Research Council (IDÆA-CSIC), c/Jordi Girona 18-26, 08034 Barcelona, Spain.
The maritime transport sector poses significant air quality concerns, particularly in nearby cities. Ultrafine particles (UFP, diameter < 100 nm) are of particular concern due to their potential health impacts. This study measured particle number concentrations (PNC), size distributions (PNSD), and other pollutants including particulate matter (PM), nitrogen oxides (NO), black carbon (BC), sulfur dioxide (SO) and ozone (O), organic markers and trace elements at a major European harbor and an urban background (UB) location.
View Article and Find Full Text PDFParticulate matter and potentially toxic element content in urban ornamental plant species to assess pollutants trapping capacity.
J Environ Manage
January 2025
Department of Plant Biology and Ecology, University of Seville, Avda. Reina Mercedes S/n, Apartado de Correos, 1095, 41012, Sevilla, Spain. Electronic address:
Urban environments are usually polluted by anthropogenic activities like traffic, a major source of potentially toxic elements (PTEs), and ornamental plant species may reduce contamination by trapping traffic-related air pollutants in their leaves. The purpose of this study was tested the trapping pollutant capacity of four species commonly used in green areas of Seville city (SW Spain) to better choose species in urban green planning. Composition of particulate matter (PM) obtained from foliar surfaces (sPM) and wax-included (wPM) was determined by EDX-SEM analysis in samples from different city locations.
View Article and Find Full Text PDFSignificant NO Formation in Truck Exhaust Plumes and Its Association with Ambient O: Evidence from Extensive Plume-Chasing Measurements.
Environ Sci Technol
January 2025
School of Environment, State Key Joint Laboratory of Environment Simulation and Pollution Control, Tsinghua University, Beijing 100084, PR China.
Vehicle nitrogen oxides (NO) significantly increase nitrogen dioxide (NO) exposure in traffic-related environments. The NO/NO ratios are crucial for accurate NO modeling and are closely linked to public health concerns. In 2020, we used a mobile platform to follow test trucks (plume-chasing) that were installed with a portable emission measuring system (PEMS) on two restricted driving tracts.
View Article and Find Full Text PDFChanges in traffic-related air pollution exposures and associations with adverse birth outcomes over 20 years in Texas.
Int J Epidemiol
December 2024
School of Nutrition and Public Health, College of Health, Oregon State University, Corvallis, OR, USA.
Background: Billions of dollars have been spent implementing regulations to reduce traffic-related air pollution (TRAP) from exhaust pipe emissions. However, few health studies have evaluated the change in TRAP emissions and associations with infant health outcomes. We hypothesize that the magnitude of association between vehicle exposure measures and adverse birth outcomes has decreased over time, parallelling regulatory improvements in exhaust pipe emissions.
View Article and Find Full Text PDFBesides traditional organophosphate esters: The ecological risks of emerging organophosphate esters in the Yangtze River basin cannot be ignored.
Environ Pollut
December 2024
State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China.
In addition to traditional organophosphate esters (tOPEs), emerging organophosphate esters (eOPEs) have increasingly been detected in the environment, but their risks remain unclear. This study detected 12 tOPEs and 7 eOPEs in surface water, sediment, and suspended particulate matter (SPM) samples from important aquatic habitats and drinking water sources in Yibin (YB), Yichang (YC), Shanghai (SH), and Poyang Lake (PY) within the Yangtze River basin. The total concentration of OPEs (ΣOPEs) in surface water, sediment, and SPM from these four regions were 22.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!