An overview: Polycyclic aromatic hydrocarbon emissions from the stationary and mobile sources and in the ambient air

NCUIR > College of Earth Sciences > Department of Atmospheric Sciences > journal & Dissertation > Item 987654321/100617

Please use this identifier to cite or link to this item: https://ir.lib.ncu.edu.tw/handle/987654321/100617

Title:	An overview: Polycyclic aromatic hydrocarbon emissions from the stationary and mobile sources and in the ambient air
Authors:	林能暉;Cheruiyot, Nicholas Kiprotich;Lee, Wen-Jhy;Mwangi, John Kennedy;Wang, Lin-Chi;Lin, Neng-Huei;Lin, Yuan-Chung;Cao, Junji;Zhang, Renjian;Chang-Chien, Guo-Ping
Contributors:	地球科學學院大氣科學學系
Keywords:	Review
Date:	2015-12-01
Issue Date:	2026-04-21 14:08:49 (UTC+8)
Publisher:	AAGR Aerosol and Air Quality Research;Cham: Springer Science and Business Media LLC
Abstract:	摘要： Polycyclic aromatic hydrocarbons are a class of semi-volatile organic carbons that are emitted from both natural and anthropogenic sources therefore are ubiquitous in nature. Their main sources are both fossil and biomass fuels as well as other feedstocks used in chemical and combustion processes. Mostly the combustion processes are PAH depletion processes rather than PAH generating processes. PAHs are emitted from both stationary and mobile sources at varying levels depending on the operation conditions such as fuels, feedstock, and control devices in use as well as process parameters for example combustion temperatures. After emission from sources, the fates of PAHs in the atmosphere include partitioning between gas and particulate phases, particle size distribution, long range transport, dry and wet deposition on to water bodies, soil, vegetation and other receptor surfaces as well as resuspension from receptor surfaces back to the atmosphere. These processes are controlled by their physiochemical properties. Additionally, it is through these processes that human beings are exposed to PAHs via inhalation, ingestion and dermal contact. Dry deposition is the major process through which PAHs from the atmosphere are made available to receptor surfaces including the human respiratory system. From studies with cumulative fractions of dry deposition and size distribution for particulate PAHs, it is evident that the coarse particles are majorly responsible for the highest fraction of deposition fluxes. This is especially true for the high molecular weight PAHs, since the low molecular weight PAHs are majorly in the gas phase, which have lower dry deposition velocities. On the other hand, the highest risk for human being comes in the form of fine particles, whose mean aerodynamic diameter is below 2.5 µm. This is because the particle bound content results and particle size distributions of PAHs indicate that the fine particles have the most PAH content owing to their large surface areas and high organic carbon content. For the wet deposition of PAHs, more research is recommended for measurement of scavenging ratios of individual PAHs, since there is a scarcity of studies focusing on this issue. PAH mutagenic activity and exposure risk of humans can be estimated using the deposition rates, toxicity levels based on benzo(a)pyrene, or biomarkers such as urinary 1-hydroxypyrene. Other parameters that have been used to evaluate the risks of various exposure groups include inhalation exposure levels (IEL), incremental lifetime cancer risk (ILCR), and estimation of maximum consumption time ( t max ). Highway toll workers, back carbon workers and food vendors in night markets are among susceptible groups identified using these biomarkers and exposure parameters. To reduce exposure to human beings, PAH emissions need to be controlled at the sources. Control and reduction of PAH emissions from various sources involves largely altering the fuel and feedstock characteristics, using air pollution control devices and/or adjusting the operating parameter’s such as temperatures and air-fuel ratios or turbulence in combustion processes. Unfortunately, albeit all the studies done on PAHs, they still remain a concern in our environment and more attention and research should be dedicated to this group of compounds. 其他題名： Aerosol Air Qual. Res 出版者： Cham: Springer Science and Business Media LLC 出版日期： 2015-12-01 出處： Aerosol and Air Quality Research, 2015-12, Vol.15 (7), p.2730-2762 版權： Taiwan Association for Aerosol Research 2015 識別號： ISSN: 1680-8584 識別號： ISSN: 2071-1409 識別號： EISSN: 2071-1409 識別號： DOI: 10.4209/aaqr.2015.11.0627
Appears in Collections:	[Department of Atmospheric Sciences] journal & Dissertation

Files in This Item:

File	Description	Size	Format
index.html		0Kb	HTML	19	View/Open

社群 sharing

Loading...