Characteristics and provenance implications of rare earth elements and Sr–Nd isotopes in PM2.5 aerosols and PM2.5 fugitive dusts from an inland city of southeastern China

Abstract

The chemical profiles of PM2.5 aerosols and PM2.5 fugitive dusts have been widely investigated in many cities; however, the characteristics and provenance implications of rare earth elements (REEs) and Sr–Nd isotopes have seldom been reported for PM2.5 aerosols and PM2.5 fugitive dusts. In this study, PM2.5 aerosol and PM2.5 fugitive (road, construction, and soil) dust samples were collected in Nanchang city, China, and analyzed for the characteristics and provenance implications via REEs and Sr–Nd isotopes. PM2.5 aerosol samples showed significantly higher ΣREE values (510.5 ± 347.4 mg kg−1) than PM2.5 fugitive dust samples (93.83 ± 35.23 mg kg−1 for road dust PM2.5, 185.0 ± 70.90 mg kg−1 for construction dust PM2.5, and 206.5 ± 34.28 mg kg−1 for soil dust PM2.5). Both the REE characteristic parameters and the chondrite-normalized REE distribution patterns indicated LREE enrichment and obvious negative Eu anomalies in both PM2.5 aerosol and fugitive dust samples. As shown in 87Sr/86Sr versus εNd(0) plot and ΣLREE/ΣHREE-Eu/Eu*-εNd(0) plot, the REEs in the PM2.5 fugitive dust samples were mainly affected by coal combustion, steelworks and construction cements and were also influenced by the background soil to some extent, while the REEs in the PM2.5 aerosol samples likely originated from both the investigated local sources and other nonlocal potential sources.