Evaluation of quartz crystals in rat lungs by X-ray diffractometry

The NIOSH (National Institute of Occupational Safety and Health)-recommended procedure of determining quartz through X-ray diffractometry was applied to rat lungs. Using a compressed air nebulizer inside a closed chamber, 150 male Sprague-Dawley rats were exposed to monodisperse particles of quartz for varying time intervals. The rats were subsequently sacrifice by cervical dislocation and their lungs were removed for ashing inside a muffle furnace at 600 degrees C for 4 hr. The ashed materials were then filtered onto silver membranes and scanned by an /-ray diffractometer. The results, expressed in MG SiO2 were compared to standard values derived from PVC filters. The values suggested that the NIOSH method could be used by biochemists to quantify minerals and crystalline structures in organic materials.