Emission characteristics of polycyclic aromatic hydrocarbons and nitro-polycyclic aromatic hydrocarbons from diesel trucks based on on-road measurements

Abstract

Polycyclic aromatic hydrocarbon (PAH) and nitro-polycyclic aromatic hydrocarbon (NPAH) emissions from 18 diesel trucks of different sizes and with different emission standards were tested in Beijing using a portable emission measurement system (PEMS). Both the gaseous-and particulate-phase PAHs and NPAHs were quantified by high-performance liquid chromatography (HPLC) in the laboratory. The emission factors (EFs) of the total PAHs from light-duty diesel trucks (LDDTs), medium-duty diesel trucks (MDDTs) and heavy-duty diesel trucks (HDDTs) were 82229.11±41906.06, 52867.43±18946.47 and 93837.35±32193.14 μg/km, respectively, much higher than the respective values of total NPAHs from their counterpart vehicles. The gaseous phase had an important contribution to the total PAHs and NPAHs, with a share rate of approximately 69% and 97% on average, respectively. The driving cycle had important impacts on the emissions of PAHs and NPAHs, especially for LDDTs and HDDTs. Higher emissions of PAHs and NPAHs were detected on non-highway roads compared to that on highways for these two types of vehicles. Compared to the results of different studies, the difference in the EFs of PAHs and NPAHs can reach several orders of magnitudes, which would introduce errors in the development of an emission inventory of PAHs and NPAHs.

Characteristics of PM2.5-Bound Polycyclic Aromatic Hydrocarbons and Nitro-Polycyclic Aromatic Hydrocarbons at A Roadside Air Pollution Monitoring Station in Kanazawa, Japan

“…However, these studies concentrated on variations in concentration, and there is a lack of analysis on the composition characteristics of PAHs and NPAHs directly emitted from vehicles. Recently, a portable emission measurement system was developed and widely used to measure the PAH and NPAH emissions from on-road vehicles [21,22]. However, these results failed to reflect the mixed emission characteristics of vehicles with different types and engine loadings.…”

Characterizing particulate polycyclic aromatic hydrocarbon emissions from diesel vehicles using a portable emissions measurement system

“…Regarding key aerosol species, researchers from Tsinghua University have developed a PEMS method for measuring real-world black carbon (BC) emissions 26 , 27 . But for organic aerosol species, a recent study measured on-road emission factors of PAH from diesel vehicles but not discussed the health and environmental implications (e.g., toxicity, source apportionment) 28 . To further explore the diesel vehicle toxic emissions and the emission differences between the PEMS method and previous method (e.g.…”

Investigation of Indoor Polycyclic Aromatic Hydrocarbons (PAHs) in Rural Northeast China: Pollution Characteristics, Source Analysis, and Health Assessment

“…Diesel vehicles are not very common in urban transportation, but in the rural areas of Northeast China, they have become an essential tool for farming and autumn harvest. Diesel vehicle exhaust contributes significantly to rural environmental pollution, and diesel vehicles exhaust contains high levels of PAHs and unsaturated fatty acids, which indirectly influence indoor concentration changes [89][90][91]. Finally, low-ring PAHs are also found as one of the main components, and low-ring PAHs would normally be considered as domestic waste combustion emissions [92].…”