Comparison of Polycyclic Aromatic Hydrocarbons and Nitropolycyclic Aromatic Hydrocarbons in Airborne and Automobile Exhaust Particulates

Abstract

Polycyclic aromatic hydrocarbons (PAH) and nitropolycyclic aromatic hydrocarbons (NPAH) in airborne particulates collected simultaneously at downtown and suburban sites and in exhaust particulates from diesel and gasoline engine vehicles were determined. The mean concentrations of all compounds in the atmosphere were lower at the suburban site. The differences between the two sites were smaller in airborne particulates than in the atmosphere. However, the difference in NPAH concentrations in particulates between the two sites was greater than the difference in PAH concentrations, suggesting that the NPAH were less stable than the PAH. The concentrations of I-nitropyrene and 1,3-, 1,6-and 1,8-dinitropyrenes were generally much higher in automobile exhaust particulates than in airborne particulates because the former were collected directly.However, 2-nitrofluoranthene and 2-nitropyrene were observed in airborne particulates but not in automobile exhaust particulates. The diurnal concentrations showed that 2-nitrofluoranthene and 2-nitropyrene might be formed by a hydroxyl radical-initiated reaction followed by nitration. I79 Downloaded by [McMaster University] at 21

Applications and Preparation Methods of Copper Chromite Catalysts: A Review

“…(PAHs) and (NPAHs) have been identified as potent mutagens and possible carcinogens. Both PAHs having 4 rings or more and NPAHs are detected in particulates exhausted from diesel and gasoline-engine vehicles, while PAHs of lower molecular weights (3 rings or below) were detected in the gaseous phase in the atmosphere and unburned diesel fuel [243][244][245]. Copper chrmomite is the active catalyst for the pyridine oxidation and NOx control [246].…”

Environmental Behaviors and Toxicities of Polycyclic Aromatic Hydrocarbons and Nitropolycyclic Aromatic Hydrocarbons

“…This is a typical pattern observed in the downtown area of Japanese cities where the major contributors of PAHs and NPAHs were automobiles. 34,35) Both PAHs and NPAHs emitted from automobiles mainly existed in the fine particulate fraction less than 2.1 µm, [36][37][38] suggesting in PM 2.5 . In Japan, urban air pollution became serious with the traffic development from the 1970s.…”

Comparison of Atmospheric Nitropolycyclic Aromatic Hydrocarbons in Vladivostok, Kanazawa and Toyama.

“…13) The concentrations of DNPs and 1-NP were higher in winter than in summer because of the highly stable air in winter and of the oil heating. 14,15) Moreover, 2-NP was not detected in diesel-particulates but was found in the atmosphere. 15 16) However, in countries using large amounts of coal energy, the contributors and behaviors of NPAHs in urban air are not known.…”

“…14,15) Moreover, 2-NP was not detected in diesel-particulates but was found in the atmosphere. 15 16) However, in countries using large amounts of coal energy, the contributors and behaviors of NPAHs in urban air are not known. Vladivostok, Russia, is a typical city which uses large amounts of coal energy.…”