Particulate matter concentrations from combustion in fireplaces in his pool Athens her holiday season, especially in the evening hours, from 10 pm. before 1 am In fact, since the temperature was not particularly low, and many fireplaces in the capital worked for heat and company, there is an alarm about what can happen in the event of a deep winter.

In particular, scientists Laboratory of Optoelectronics and Lasers of the National Technical University of Athens have developed an innovative laser remote sensing system (lidar technique) that is able to track the spatial and temporal changes in the vertical distribution of bioparticles in the lower atmosphere. These particles are emitted as smoke, either from the combustion of xylomass (biomass) for domestic use (heating in fireplaces or wood-burning stoves) and secondary sources (catering facilities, charcoal grills), or from plants as pollen.

“This system is based on the detection of fluorescence of bioparticles when they are activated by ultraviolet laser radiation. The measurements showed an increase in the concentration of bioparticles in the basin of Athens in the evening, from the ground to the height of the surrounding mountains (for example, 1000-1200 meters), which proves that the atmospheric masses contaminated with bioparticles linger at low altitudes. Says Professor Alexandros Papagiannis “K”., Head of the Laboratory of Optoelectronics and Lasers, National Technical University of Athens. “The highest concentrations of bioparticles in the basin were measured during the holiday period from December 21, 2022 to January 8, 2023, as confirmed by the corresponding measurements of particulate matter PM2.5 (less than 2.5 µm in diameter) in the Zografou District (urban backdrop) of National Network of Pan-Greek Atmospheric Composition and Climate Change Infrastructure (PANAQUEIA), which is the only integrated research infrastructure (AI) on atmospheric composition and climate change.” And, as Mr. Papagiannis notes, the area of ​​the Polytechnic Institute is not densely populated, and therefore the concentrations recorded are much lower than in the corresponding areas with dense fabric and several active fireplaces.

According to NTUA researchers, during peak hours of operation of fireplaces, PM2.5 concentrations of suspended particles reached very high values ​​(of the order of 120-150 µg/m3), creating a very high background of pollutants, which are also supplemented by emissions from other sources (vehicle traffic, industrial activities, other types of heating, etc.). “During peak periods, PM2.5 concentrations were three times the EU target, while overall average background values ​​doubled over the holiday period compared to the previous days in December,” emphasizes Mr. Papagiannis.

It is also noteworthy that, as the records of the system show, PM2.5 particles linger relatively low in the atmosphere, at altitudes up to 400-600 meters, creating a curtain of pollution that significantly affects the areas where the inhabitants of Athens live. move and breathe and pelvis.

Health impact

“Particles from biomass combustion have been blamed for serious human health effects (through oxidative stress and inflammation), especially when exposed for a long time and increased in concentration, since biomass combustion, in addition to the emission of particles, is accompanied by emissions of gases (for example, hydrocarbons ), which are highly toxic and cause diseases of the cardiovascular and respiratory systems, children and the elderly are especially vulnerable,” he adds. In fact, particles as small as 2.5 micrometers (PM2.5), precisely because they are very small, can penetrate deeper into the human body. This study, carried out by the Laboratory of Optoelectronics and Lasers of the National Technical University of Athens, shows that the problem of air pollution in Athens, especially from burning wood in fireplaces, remains relevant even if the weather conditions do not lead to severe consequences. still.