Characterisation of and exposure of workers to tailings dust at South African platinum mines

摘要

The objective of this study was to characterize tailings dust according to its particle size and elemental content and to evaluate personal exposure of workers doing different types of work, to tailings dust. A 32 element particle scan was done on total dust samples. Al, Ca, Fe and Mg were found in relatively high amounts with lesser amounts of Cr, Zn, Mn, Ti, Cu and Li. A mean particle size volume percentage of 9.8% was found to be respirable (<7 mu m), 87.3% were inhalable dust (> 10 mu m) and a mean thoracic fraction of 2.9 volume %. A statistically significant difference was found between exposures of workers at tailings dams 1 and 3 and dams 2 and 3. The personal tailings dust exposures of Pipe Line Labourers and Mud Guards were only significant on a 10% level. It is concluded that the exposures of the workers on the tailings dams were very low. The risk of toxic consequences due to the elemental content of the dust is considered to be extreme low.