Dust influence on oxygenated polycyclic hydrocarbons and aliphatic ketones in Dushanbe particulate matter

¹ Leibniz Institute for Tropospheric Research (TROPOS), Permoserstr. 15, 04318 Leipzig, Germany
² National Academy of Sciences of Tajikistan, Physical-Technical Institute, Atmospheric Physics Laboratory, Ayni str.299/1, 734063, Dushanbe, Tajikistan

^* Corresponding author: herrmann@tropos.de

Abstract

In the Central Asian region, susceptibility to dust storms and escalating anthropogenic emissions poses challenges for air quality as well as environmental health. This study explores the temporal and seasonal dynamics of oxygenated polycyclic aromatic hydrocarbons (OPAHs) and aliphatic ketones in particulate matter during the Central Asian Dust Experiment (CADEX) in Dushanbe, both determined by Curie-Point Pyrolysis / Gas Chromatography Mass Spectrometry (CPP-GC/MS). The results revealed pronounced variations in the concentrations of OPAHs, particularly 9,10-anthracendione, as the most dominant compound, with a marked dominance in winter. The aliphatic ketones also displayed robust temporal variations, closely associated with combustion sources with 2-nonadecanone and 2-heptadecanone emerging as the dominant compounds. Both compound groups showed higher concentrations in winter. The impact of dust events on OPAHs was more noticeable during summer, with limited influence observed in winter. Combustion sources, particularly wood and coal burning, played a predominant role in shaping the observed concentrations, explaining most of the winter dominance. The elevated levels of OPAHs and ketones in Dushanbe underscore the need for implementing local mitigation strategies to curb exposure and potential health risks. This comprehensive analysis enhances our understanding of the intricate interplay between mineral dust, combustion sources, and atmospheric chemical composition, contributing to the development of air quality management strategies, in regions prone to dust events.