Spatial and temporal PAH concentrations in Zaragoza, Spain.

Area of Science:

• Environmental Chemistry
• Atmospheric Science
• Analytical Chemistry

Background:

• Polycyclic Aromatic Hydrocarbons (PAHs) are significant air pollutants originating from incomplete combustion processes.
• Atmospheric PAHs can be adsorbed onto solid particles, influencing their environmental fate and human exposure.
• Understanding PAH sources and behavior is crucial for urban air quality management.

Purpose of the Study:

• To quantify seven Polycyclic Aromatic Hydrocarbons (PAHs) in the atmospheric solid phase in Zaragoza, Spain.
• To investigate the spatial and temporal variations of PAH concentrations and their sources.
• To analyze the influence of meteorological factors on PAH levels.

Main Methods:

• Synchronous fluorescence spectroscopy (FS) was employed for PAH analysis.
• Sampling was conducted in four urban and suburban locations in Zaragoza from October 1999 to September 2001.
• Data analysis correlated PAH concentrations with environmental parameters like temperature, humidity, and wind direction.

Main Results:

• PAH concentrations were similar across sites, but Benzo[a]pyrene (BaP) and Coronene (Cor) were highest near heavy traffic areas.
• A clear seasonal trend was observed, with higher PAH levels during colder months.
• Total PAH concentration positively correlated with relative humidity and negatively with temperature.
• Specific wind directions (East, North-East) were associated with higher PAH emissions, while North-Westerly winds (cierzo) indicated cleaner air.

Conclusions:

• Local urban and industrial activities are significant sources of atmospheric PAHs in Zaragoza.
• Heavy traffic contributes substantially to specific PAH concentrations, particularly BaP and Cor.
• Seasonal variations and meteorological conditions significantly influence PAH distribution and concentration in the atmosphere.