Polycyclic aromatic hydrocarbons in pine needles (Pinus halepensis) along a spatial gradient between a traffic intensive urban area (Barcelona) and a nearby natural park

van Drooge, Barend L.; Garriga, Guillem; Grimalt, Joan O.

Polycyclic aromatic hydrocarbons in pine needles (Pinus halepensis) along a spatial gradient between a traffic intensive urban area (Barcelona) and a nearby natural park

2014

van Drooge, Barend L. | Garriga, Guillem | Grimalt, Joan O.

Polycyclic aromatic hydrocarbons (PAHs) are emitted into the atmosphere from combustion of fuels, such as emissions from traffic in urban areas, which on their terms can be important sources for the translocation of these toxic compounds to the surrounding region. Pine needles can be used as time–integrated passive air–samplers for PAHs. Pine needles were collected between 2009 and 2011 along a spatial gradient (5km) from urban background sites towards sites situated in a natural park (Collserola) within the metropolitan area of Barcelona. City samples showed PAH levels that were two times higher than the levels in the natural park. A seasonal trend was reflected by the substantially higher PAH levels in pine needles collected in the colder sampling period than those collected in the warmer period. The observed trend can be explained in terms of source emission strength, dilution and photo–chemical degradation, while also gas–pine needles partitioning may have played an important role. The city is the major source area for the translocation of PAHs towards the nearby natural park.

اظهر المزيد [+]