Výzkum složení silniční prachu za účelem identifikace zdrojů znečištění

Abstract

The submitted dissertation deals with the composition of street dust and the identification of sources of pollution. Street dust deposited on roads can be resuspended to the environment and negatively affect air quality and human health. To identify sources of pollution, street dust samples were collected and analyzed in selected parts of Ostrava and Olomouc. Street dust was sampled after the winter and summer period. A detailed study of street dust was performed to determine its amount, grain size, magnetic susceptibility, and heavy metal concentrations. In selected localities, street dust contains increased concentrations of heavy metals. These heavy metals present a risk to the environment.

The amount of dust per m2 of road surface in summer, resp. winter, was highly variable for individual districts of Ostrava (47–1375 g/m2 resp. 23.5–1362 g/m2), with arithmetic mean (240±184 g/m2 resp. 429±288 g/m2). The highest average concentration of metals occurred in the grain size class 0.063–2 mm during the winter and summer periods. The highest concentrations in road dust from Ostrava are represented by the series Fe> Mn ˃ Zn ˃ Cr ˃ Cu ˃ Pb ˃ As. High values of magnetic susceptibility of street dust are caused by the metallurgical industry (including not only air pollution load, but also the use of slag for construction purposes), which was confirmed by the significant enrichment of Cu, Cr and Zn. Metals except Cu are bound in magnetic particles and have a high correlation coefficient with magnetic susceptibility. It is recommended to use the results obtained after the summer period to identify the sources of pollution, as there is not influenced by materials for winter maintenance of roads. It has been shown that using various combinations and connections of the proposed methods, it is possible to identify the percentage proportion of pollution from individual sources.