Size distribution of polycyclic aromatic hydrocarbons in a roadway tunnel in Lisbon, Portugal

Abstract

Atmospheric aerosols of four aerodynamic size ranges were collected using high volume cascade impactors in an extremely busy roadway tunnel in Lisbon (Portugal). Dust deposited on the tunnel walls and guardrails was also collected. Average particle mass concentrations in the tunnel atmosphere were more than 30 times higher than in the outside urban background air, revealing its origins almost exclusively from fresh vehicle emissions. Most of the aerosol mass was concentrated in submicrometer fractions (65%), and polycyclic aromatic hydrocarbons (PAH) were even more concentrated in the finer particles with an average of 84% of total PAH present in sizes smaller than 0.49 mu m. The most abundant PAH were methylated phenanthrenes, fluoranthene and pyrene. About 46% of the total PAH mass was attributed to lower molecular weight compounds (two and three rings), suggesting a strong influence of diesel vehicle emissions on the production of local particulate PAH. The application of diagnostic ratios confirmed the relevance of this source of PAH in the tunnel ambient air. Deposited dust presented PAH profiles similar to the coarser aerosol size range, in agreement with the predominant origin of coarser aerosol particles from soil dust resuspension and vehicle wear products.

The Mass Distribution of Particle-Bound PAH Among Aerosol Fractions: A Case-Study of an Urban Area in Poland

“…In summer, the distribution of ΣPAH and particular PAH with respect to the aerodynamic diameter of particles they are bound to, the values of BEQ and ΣPAH carc /ΣPAH were similar to those from other sites in the world Akyüz & Çabuk, 2008). The contribution of PM 1 -and PM 2.5 -bound ΣPAH to ΣPAH was in Zabrze, like elsewhere (Chrysikou et al, 2009;Kong et al, 2010;Makkonen et al, 2010;Oliveira et al, 2011), very high (99 and 82% in winter and 77 in 69% summer, respectively).…”

“…BaP and ΣPAH tend to accumulate in the finest particles of PM (Table 4). Like in Zabrze, this tendency may be observed in the road tunnel in Lisbon, Portugal (Oliveira et al, 2011) and at the urban background and traffic stations in Los Angeles, USA (Phuleria et al, 2007). (Odabasi et al, 1999;Hong et al, 2007).…”

Occurrence and carcinogenic potential of airborne polycyclic aromatic hydrocarbons in some large-scale enclosed/semi-enclosed vehicle parking areas

“…According to the third national death reason survey of China in 2008 (http://www.moh.gov.cn/), cancer is now the primary cause of death in Chinese cities, accounting for ∼25% of all deaths; and lung cancer has replaced liver cancer in causing the largest Typically, highly carcinogenic PAHs in exhaust are mainly associated with the particulate matters emitted from motor vehicles [8,9]. These contain fine particles with the peak diameter between 0.1 and 0.2 m [10,11], which can be inhaled deeply into lung.…”

“…Traffic areas, e.g. highway tunnel [9], road intersection [14], traffic roadside [15], distribution center and bus terminal [16], etc., all showed significantly higher airborne PAH levels than common urban areas. Data also indicate that traffic-related workers, e.g.…”

The occurrence and source evaluation of polycyclic aromatic hydrocarbons in urban atmosphere using moss as biomonitor and GC-MS analysis

“…In highly populated and heavily urbanized or industrialized areas, the most significant emission sources are residential heating, coal gasification, asphalt production, and motor vehicle exhaust [4]. In order to identify and assess the source of PAHs, numerous studies have been published most of them based on different diagnostic ratios [5][6][7][8].…”