The “Dust Haze” Effect in the Atmosphere of a Megapolis

Local anthropogenic sources of coarse aerosol (dust) in cities cause a “dust haze” effect on the territory adjacent to the source sites of such aerosol (construction sites, areas of reconstruction of roads and buildings), due to a sharp increase in the concentration of PM10 particles in the near-surface air. Two such episodes recorded in the center of Moscow in the summers of 2021 and 2024 are analyzed. The variability of the mass concentration and particle size distribution of dust aerosols under abnormally high atmospheric pollution (PM10 concentration above the maximum permissible concentration) is studied. A comparison of the characteristics of urban construction dust and arid aerosol in the atmosphere of the desert zones of Kalmykia showed similarities between them in the increased content of lithophilic elements (of natural origin). However, in the city, the concentrations of potentially toxic elements (heavy metals, metalloids, etc.) typical for urban dust are higher in aerosols from construction sources. The dust pollution of the megapolis atmosphere under the influence of intense construction sources not only worsens visibility and creates uncomfortable conditions for population living, but also creates great risks for the urban environment and human health.