Clay occlusion of respirable quartz particles detected by low voltage scanning electron microscopy-x-ray analysis.
Wallace-WE; Harrison-J; Keane-MJ; Bolsaitis-P; Eppelsheimer-D; Poston-J; Page-SJ
Ann Occup Hyg 1990 Apr; 34(2):195-204
The aluminum (7429905) and silicon (7440213) content of respirable sized dust particles from a clay mine and mill were examined by scanning electron microscopy/energy dispersive x-ray analysis at incident electron energies of 5 to 20 kiloelectron volts (KeV). The high silica content particles, with a silicon to silicon plus aluminum signal fraction of 0.9 or greater measured at 20keV, demonstrated a decrease in the silicon fraction of signal with decreasing incident electron energy, down to values between 0.6 and composition. The authors conclude that this behavior may be due to a heterogeneous particle structure in which an aluminosilicate coating occludes the surface of a silica particle core. The coating was observed to survive incubation in a major component of pulmonary surfactant.
NIOSH-Author; Chemical-analysis; Analytical-chemistry; Mineral-dusts; Microscopic-analysis; Silica-dusts; Mining-industry; Respirable-dust
IH; Journal Article
West Virginia University
Annals of Occupational Hygiene