VOC tracers from aircraft activities at Beirut Rafic Hariri International Airport

This is the first study to assess the speciation of 48 VOCs from around 100 commercial aircraft under real operation, as close as possible to aircraft engines during the various modes of the landing/takeoff (LTO) cycles to identify special aircraft fingerprints and markers. Also, Jet A-1 kerosene vapor, gasoline exhaust, and the ambient airport concentrations were assessed. Air samples were taken at Beirut Rafic Hariri International Airport inside adsorbent tubes using a portable automatic remote sampler and analyzed using gas chromatographic techniques (GC-MS and GC-FID). Results showed that heavy alkanes (C8-C14, mainly n-nonane and n-decane), which contributed to about 51–64% of the total mass of heavy VOCs emitted by aircraft, and heavy aldehydes (nonanal and decanal) – although to a lesser amount – can be considered as potential tracers for aircraft emissions due to both their exclusive presence in aircraft-related emissions and their absence from gasoline exhaust emissions. On the other hand, the total concentration of heavy alkanes in the airport's ambient air was 47% of the total mass of heavy VOCs measured. No aircraft tracer was identified among the light VOCs (≤C7); however, results showed that emissions of light VOCs decrease as the engine power increases. Also, auxiliary power unit (APU) emissions were identified to be of the same order of magnitude as main engine emissions. This study opens the door for future studies aiming at evaluating the impact of airport activities on air quality and human health within or away from the airport vicinity.