Results of expedition measurements of PM10, PAHs and mercury above the water area of Lake Baikal in August 2023

Abstract

As a continuation of regular research to obtain information about mechanisms and sources of air pollution above the water area of Lake Baikal, we present the results of the expeditionary studies on the concentrations of РМ₁₀, polycyclic aromatic hydrocarbons and gaseous elemental mercury in the near-water layer of the atmosphere above Lake Baikal in August 2023. On the route of the vessel along the perimeter of the lake, the concentrations of pollutants in the near-water atmosphere increased near the local sources of air pollution located on the coast of the southern basin (Listvyanka, Slyudyanka and Baikalsk) as well as at the source of the Angara River with the northwesterly transport from the industrial cities of the Baikal region. Over the study period, the РМ₁₀ concentrations averaged 6.0 µg/‌m³, PAHs–1.1 ng/m³, and gaseous elemental mercury–0.75 ng/m³, which was lower than the values recorded during wildfires between 2016 and 2020 in some areas of Siberia. The resulting concentrations of the investigated air components did not exceed air quality standards. Pairwise correlations during the study period were high between РМ₁₀ and PAHs (0.71) and low between PAHs and mercury (0.21).