Abstract: Triammonium aurin tricarboxylate (aluminon) has been used to localize aluminum in 2 μm sections of undecalcified, methyl methacrylate embedded bone obtained from patients with terminal chronic renal failure. Aluminum appeared in four cases as bright red lines at the mineralized-bone boundary. In two cases, however, purplish lines were found and one patient showed red as well as purplish lines. Laser microprobe mass analysis (LAMMA) identified aluminum at the location of the red lines and both aluminum and iron at the purplish lines. Furthermore, both iron and aluminum were found in histiocytic bone marrow cells, which showed brownish aluminon staining. It appears that when aluminum and iron occur together, aluminon staining may yield aberrant results. This study shows that LAMMA can be used for the identification of elements sought by histochemical methods and thus permits the evaluation of their staining effects.

Abstract: Airborne dust particles were collected in a return airway of a South African gold mine using a 7-stage, single-orifice cascade impactor. Between 70 and 130 individual particles were analysed on each stage using automated electron-probe x-ray microanalysis (EPXMA). Particle size and shape parameters are given for different classes of particles sorted by elemental composition. Silicon-rich particles are the most abundant overall, while chlorine-rich particles dominate (up to 80%) in the range 0.21.0 μm. It is shown that EPXMA characterisation of particles can be used to infer relative contributions of various particle sources and dust generating processes to the total dust concentrations in mine atmospheres. An understanding of the nature and source of particles is essential for any source control strategy. We conclude that the EPXMA technique merits inclusion in the repertoire of techniques used for characterising underground dust.