Use of Chemiluminescence Assays to Monitor the Surface Characteristics and Biological Reactivity of Freshly Fractured vs Aged Silica

Details

• Personal Author:
  Castranova, Vincent ; Dalal NS ; Vallyathan V ; Van Dyke K
• Description:
  Evidence suggests that pulmonary disease which results from exposure to crystalline silica may be related to the direct cytotoxic interaction of silica with lung tissue as well as tissue damage caused by reactive products secreted from alveolar macrophages exposed to silica. Previous studies from our laboratory have used electron spin resonance spectroscopy to demonstrate that mechanical crushing or grinding of crystalline silica in air could produce significant amounts of silica-based radicals on the particulate surface and that these silicon- oxygen radicals could react with aqueous media to generate hydroxyl radicals. Our previous studies have also related these radicals to the cytotoxicity of silica and the ability of silica to activate alveolar macrophages. The current study describes the use of a simple chemiluminescence technique to monitor the generation of surface radicals on silica after crushing, the silica-induced generation of radicals in aqueous media, and the activation of secretion of reactive species from alveolar macrophages exposed to freshly ground silica. Chemiluminescence was monitored with a Berthold Luminometer. Crushing crystalline silica with an agate ball mill for 30 min results in the generation of surface silicon-based radicals which can be detected in air by measurement of chemiluminescence. Furthermore, chemiluminescence is also detect able when freshly ground silica is suspended in HEPES-buffered medium. Chemiluminescence of freshly ground silica decays with time both in air and suspension and is not detectable using uncut or aged silica. In vitro exposure of rat alveolar macrophages to freshly ground silica results in the generation of chemiluminescence at substantially greater levels than produced by silica alone. Although aged silica can activate chemiluminescence from alveolar macrophages, the degree of activation is far less than with freshly ground silica. These studies indicate that chemiluminescence represents a useful assay to monitor the surface properties and biological activity of silica and to evaluate the use of coatings or drug treatments in deactivating silica or preventing the activation of alveolar macrophages by silica. [Description provided by NIOSH]
• Subjects:
  Cytotoxins Dust Free Radicals Lung Occupational Health Respiratory System Safety Silicon Dioxide
• Keywords:
  Biological Effects Chemiluminescence Immunoassay Cytotoxic Effects Free Radical Generation Free Radicals Mineral Dusts Pulmonary Effects Respirable Dust Silica Silicosis
• Publisher:
  N.A.T.O. (North Atlantic Treaty Organization)
• Document Type:
  Text
• Genre:
  Abstract or Summary
• Place as Subject:
  OSHA Region 3 ; West Virginia
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Division:
  DRDS - Division of Respiratory Disease Studies
• Topic:
  Workplace Safety & Health
• Location:
  North America
• Pages in Document:
  36
• NIOSHTIC Number:
  nn:20059126
• Citation:
  Fourth International Workshop on Effects of Mineral Dusts on Cells, September 21-23, 1988, Orford, Quebec, Canada. Brussels, Belgium: N.A.T.O. (North Atlantic Treaty Organization), 1988 Sep; :36
• CAS Registry Number:
  Quartz (SiO2) (CAS RN 14808-60-7)
• Federal Fiscal Year:
  1988
• Peer Reviewed:
  False
• Source Full Name:
  Fourth International Workshop on Effects of Mineral Dusts on Cells, September 21-23, 1988, Orford, Quebec, Canada
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:7a74f52e75123fcb18a38818ac3f86fc98e33893045d2c1431a0d1f93c1060aef64e3926891ca760b30847918ae23473808bddd3d693be3cd6dcd9a433ee144a
• Download URL:
  https://stacks.cdc.gov/view/cdc/223439/cdc_223439_DS1.pdf
• File Type:
  [PDF - 967.00 KB ]