Abstract
Settled dust samples were collected from Qingdao urban area to analyze the spatial distribution, chemical speciation and sources of metals, and to evaluate the health risk of metals from atmospheric dust. The average contents of Hg, Cd, Cr, Cu, Ni, Pb and Zn in the atmospheric settled dust of Qingdao were 0.17, 0.75, 153.1, 456.7, 60.9, 176.0 and 708.3 mg/kg, respectively, which were higher than soil background values. The mean exchangeable metal and carbonated-associated fraction proportions of Cd, Zn and Pb were 43.6%, 26.1% and 15%, which implies that they have high mobility and bioavailability. Higher contents of heavy metals appeared in old city areas because of the historical accumulation of metals. Principal component analysis showed that combustion sources partially contributed to Pb, Zn and other trace metals. Hg, Pb and Zn mainly originated from business, human activities and municipal construction. Cd and Cu from settled dust of the old city originated from the erosion and ageing of construction materials. The non-carcinogenic risk rankings for the seven determined heavy metals were ingestion > dermal > inhalation. Cd, Cr and Ni from settled dust showed a low carcinogenic risk. The health risks of Cr, Cu and Pb were higher in old city areas and, therefore, need special attention.
Highlights
Atmospheric settled dust refers to the particles that settle on the ground as a result of their own gravity
Settled dust is thought to be the carrier and reaction bed of pollutants; it has an important impact on environmental changes, the climate and human health [9,10,11]
10.3 times the soil background values, respectively. This indicates the enrichment of heavy metals in settled dust
Summary
Atmospheric settled dust refers to the particles that settle on the ground as a result of their own gravity. Their particle size is mostly larger than 10 μm, which is an important indicator of air pollution monitoring [1]. Due to the different sources of pollutants and the different effects of the physical and chemical processes, the chemical composition of the settled dust in the atmosphere is complex, including metal particles, inorganic particles and organic particles [2,3,4]. Settled dust is thought to be the carrier and reaction bed of pollutants; it has an important impact on environmental changes, the climate and human health [9,10,11]. High contents of heavy metals in atmospheric particles have been observed, especially in fine particles [12,13]
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
