Benzene and Toluene Levels in the Atmosphere of Athens During Wintertime: Influence of Financial Crisis on Traffic and Biomass Burning Emissions

Abstract

Since 2009, Greece experienced a financial crisis leading to a decrease in traffic emissions and industrial activity. In addition since winter 2013, smog events were observed in the greater Athens area (GAA) from the use of wood for heating purpose. During wintertime in 2009 and 2014–2015 a DOAS system was continually operated in the Athenian suburb of Aegaleo. This system, monitors basic air pollutants (O₃, NO₂, SO₂), as well as benzene and toluene (BT). Additionally in winter 2014–2015 campaign measurements of CO and BC were also available. A comparison between oxidant (O₃ and NO₂) and BT levels during these two years period (2009 vs. 2014–2015) can provide very useful information on the influence of financial recession on traffic and biomass burning on the air of GAA. The mean diurnal variation of both benzene and toluene, for 2009 and 2014–2015, revealed that (a) the morning hours peak in BT related to traffic was reduced in 2014 compared to 2009 by almost 50 % in line with NO₂ decrease, (b) during the afternoon/night hours in November and December 2014 the traffic BT peak was almost disappeared and replaced by another one delayed (by almost 2 h) compared to 2009 and assigned to biomass burning.