Measurements of semivolatile and particulate polycyclic aromatic hydrocarbons in a bus station and an urban tunnel in Salvador, Brazil

Abstract

Motor vehicles constitute a significant source of polycyclic aromatic hydrocarbon (PAH) emissions to the atmosphere. Particle-phase priority pollutant PAH concentrations and total suspended particle mass (TSP) were measured in the Lapa bus station and the Americo Simas Tunnel, located in the city of Salvador, Brazil. Separate samples were collected at the bus station at different times of the day, including rush-and non-rushhour periods. The highest concentrations for nearly all 16 priority PAHs measured at the bus station were observed at 18:30 h, with chrysene showing the highest mean value (26.6 ng m 23 ). The highest average PAH concentrations measured in the tunnel were observed for pyrene (79.4 ¡ 11.5 ng m 23 ) followed by fluoranthene (39.0 ¡ 5.2 ng m 23 ) and chrysene (28.0 ¡ 4.17 ng m 23 ). TSP levels reached 423 mg m 23 in the bus station, and values as high as 2 mg m 23 in the tunnel. The measured Salvador tunnel PAH profiles are very similar to the Salvador bus station profiles, and are similar to PAH profiles reported for the Kojouike Tunnel, located in Kurashiki City, Japan, and the Caldecott Tunnel, located in Berkeley, California.

Multivariate optimization of a GC–MS method for determination of sixteen priority polycyclic aromatic hydrocarbons in environmental samples

“…In this study, we employed 16 Chromatographic analyses were carried out starting with procedures already described in the literature [28 -32] as well as acquired expertise of this research group in PAH analysis by GC -MS [23,33]. Briefly, our starting column oven program, set in a univariate manner, was: (i) oven: 608C (1 min) 2808C (58C/min) 2808C (15 min); (ii) injector: 2708C, splitless mode; (iii) transfer line: 2708C, (iv) ion source: 2308C, (v) analyzer: 1508C; electron impact energy: 70 eV [23,33].…”

“…Briefly, our starting column oven program, set in a univariate manner, was: (i) oven: 608C (1 min) 2808C (58C/min) 2808C (15 min); (ii) injector: 2708C, splitless mode; (iii) transfer line: 2708C, (iv) ion source: 2308C, (v) analyzer: 1508C; electron impact energy: 70 eV [23,33]. Although it is possible to acquire reliable data for a part of the sixteen PAHs considered using this procedure, there are some problems: (i) it is not possible to attain completely satisfactory resolution for the following pairs of isomers: phenanthrene/ anthracene, benzo (ii) the lower the vapor pressure of the PAH, the less sharp is its peak; and (iii) the proposed temperature program takes 60 min for each sample to be completely eluted from column.…”

Quantification and source identification of atmospheric particulate polycyclic aromatic hydrocarbons and their dry deposition fluxes at three sites in Salvador Basin, Brazil, impacted by mobile and stationary sources

“…22 It should be mentioned that particulate PAH, measured in urban air and inside roadway tunnels, have been found in the respirable size range with a significant amount in the ultrafine fraction of the particulate matter. 10,[23][24][25][26] The aim of the present work was to determine the atmospheric concentrations and profiles of 16 particlephase US EPA priority PAH pollutants, present at the same three sites previously studied, 27 namely: (i) Lapa bus station, strongly impacted by heavy-duty diesel vehicles and which has been already characterized for high molar mass n-alkanes and polycyclic aromatic hydrocarbons; 28 (ii) Aratu Harbor, impacted by an intense movement of goods, including metal ores and chemicals and near industrial centers and; (iii) Bananeira Village, located on Maré Island, a non vehicle-influenced site, with activities such as handcraft work and fisheries, although placed near the port (Figure 1). Even though Lapa bus station was studied 27,28 some years ago, nowadays this station has undergone architectural adjustments (previously it was an indoor facility and now there is a "half-opened" space that makes pollutant dispersion more possible).…”

Aspectos ecotoxicológicos de hidrocarbonetos policíclicos aromáticos

“…Processos diagênicos (qualquer mudança química, física ou biológica sofrida por um sedimento após sua deposição inicial, sob condições relativas de baixa temperatura e pressão) também podem formar HPAs através de precursores biogênicos, como por exemplo, a formação de terpenos, derivados de material vegetal e que potencialmente geram hidrocarbonetos polinucleados como perilenos, retenos e crisenos, assim como em alguns compostos derivados de fenantreno (Meyer & Ishiwatari 1993, Silliman et al 1998. Porém a principal via de HPAs no meio ambiente está nas atividades humanas presentes em grandes centros urbanos e complexos industriais (Pereira et al 2002, Torres et al 2002, Garban et al 2002. Uma quarta fonte potencial de HPAs está na síntese biogênica desses compostos.…”