Variation and health risks of the potentially toxic metals in dust around an industrial hub

Abstract

The port area around Saldanha Bay, South Africa, is an industrial hub that processes large quantities of mining material and produces metals and steel, which leads to the visible emission of industrial dust. This study addresses the spatial and temporal variation of potentially toxic metals in the dust surrounding the industrial hub of Saldanha Bay and the potential health risks associated with them. Monitoring by the Saldanha Bay Municipality using dust buckets gives insight into the monthly Fe, Mn, Cu, Pb, and Zn content and deposition fluxes from 2016 to 2023. In addition, an extended sampling effort with Big Spring Number Eight (BSNE) samplers allowed us to additionally determine the Al, As, Ba, Cd, Co, Cr, Mo, Ni, Sb, Se, Sn, Sr, and V content in the dust particles. Results showed that in general, the Fe, Mn and Zn fluxes increased over time while the Pb flux decreased. Health risk indices suggest that the Pb and Mn content in the dust particles could pose a significant risk to public health. Certain regions in the study area are at higher risk than others, illustrating the need to monitor the spatial variability. Furthermore, the content of Co, Cu, Mn, and Ni is high compared to published concentrations in other urban areas around the world. Future work could investigate the precise origin of each metal to develop appropriate mitigation plans and protect public health in such industrial areas.