The assessment of effectiveness of SEM- EDX and ICP-MS methods in the process of determining the mineralogical and geochemical composition of particulate matter deposited on spider webs

Abstract

Air pollution can be monitored using many different methods. In this paper, we aimed to test and validate two analytical techniques based on complex mineralogical and geochemical analyses with the use of spider webs as a passive sampler. The samples of spider webs were collected in 2018 in polluted areas in the vicinity of the copper smelter Głogów (Poland). Samples were analysed using scanning electron microscopy with energy dispersive x-ray analysis (SEM-EDX) to obtain not only the information about the form and size of studied particles but also their origin (anthropogenic or terrigenous). Geochemical analysis was performed using inductively coupled plasma mass spectrometry (ICP-MS), providing the total amount of chosen and potentially toxic elements. The frequency of metal occurrence in atmospheric particles identified with the use of SEM-EDX was compared with the results from ICP-MS and recalculated into the percentage of contribution. A significant correlation between chemical and mineralogical composition was found demonstrating that the phases and minerals were correctly recognised and properly divided into groups. For elements such as Pb, Zn, and Cu, which are the major contaminants in the study area, the validation of the method gave good results, revealing the convergence of results for most sampling points. Finally, our study showed that the results obtained by SEM-EDX analysis can be comparable to quantitative results (ICP-MS analysis).