Experimental dissolution of road dust in simulated environmental and biological fluids

Abstract Road dust from six sites in Philadelphia, PA (USA) was characterized using a multi-analytical approach and subsequently subjected to dissolution in various types of fluids. Quartz and dolomite are the predominant minerals in the studied road-dust samples, with smaller amounts of calcite, feldspars, micas, and clay minerals also present. A comparison of the elemental bulk concentrations with those of a previous study conducted in the same locations documents temporal variability in the composition of the road dust. In the dissolution experiments using the EPA 3050B method as well as synthetic rainwater, simulated gastric fluid, and Gamble's solution (simulated lung fluid), it was demonstrated that in general, increasing acidity resulted in enhanced release of Al, Fe, V, Cr, Ni, Cu, Zn, and Pb. The results further showed that the finer road-dust fraction (