Comparison of Free Radical Generation by Pre- and Post-Sintered Cemented Carbide Particles

Details

• Personal Author:
  Bukowski VC ; Harvey CJ ; Leonard, Stephen S. ; Stefaniak, Aleksandr B.
• Description:
  Rapid generation of reactive oxygen species (ROS) may occur in response to cellular contact with metal particles. Generation of ROS by cobalt and/or tungsten carbide is implicated in causing hard metal lung disease (HMD) and allergic contact dermatitis (ACD). In this study, ROS generation and particle properties that influence radical generation were assessed for three sizes of tungsten, tungsten carbide, cobalt, admixture (tungsten carbide and cobalt powders), spray dryer, and post-sintered chamfer grinder powders using chemical (H2O2 plus phosphate buffered saline, artificial lung surfactant, or artificial sweat) and cellular (RAW 264.7 mouse peritoneal monocytes plus artificial lung surfactant) reaction systems. For a given material, on a mass basis, hydroxyl (·OH) generation generally increased as particle size decreased; however, on a surface area basis, radical generation levels were more, but not completely, similar. Chamfer grinder powder, polycrystalline aggregates of tungsten carbide in a metallic cobalt matrix, generated the highest levels of ·OH radicals (p < 0.05). Radical generation was not dependent on the masses of metals, rather, it involved surface-chemistry-mediated reactions that were limited to a biologically active fraction of the total available surface area of each material. Improved understanding of particle surface chemistry elucidated the importance of biologically active surface area in generation of ROS by particle mixtures. [Description provided by NIOSH]
• Subjects:
  Free Radicals Occupational Health Respiratory Tract Diseases Safety Skin
• Keywords:
  Author Keywords: Dermal Exposure Free-radicals Hard-metals Hard Metal Inhalation Exposure Particle Physicochemical Properties Pulmonary-system-disorders Reactive Oxygen Species Respiratory-system-disorders Skin-exposure
• ISSN:
  1545-9624
• Document Type:
  Text
• Genre:
  Journal Article
• Place as Subject:
  OSHA Region 3 ; West Virginia
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Division:
  DRDS - Division of Respiratory Disease Studies ; HELD - Health Effects Laboratory Division
• Topic:
  Workplace Safety & Health
• Location:
  North America
• Pages in Document:
  23-34
• Volume:
  7
• Issue:
  1
• NIOSHTIC Number:
  nn:20036087
• Citation:
  J Occup Environ Hyg 2010 Jan; 7(1):23-34
• Contact Point Address:
  Stephen S. Leonard, Mail Stop 2015, 1095 Willowdale Road, Morgantown, WV 26505
• Email:
  SLeonard@cdc.gov
• CAS Registry Number:
  Cobalt (CAS RN 7440-48-4) ; Tungsten (CAS RN 7440-33-7) ; Tungsten carbide (CAS RN 11130-73-7)
• Federal Fiscal Year:
  2010
• NORA Priority Area:
  Manufacturing
• Peer Reviewed:
  True
• Source Full Name:
  Journal of Occupational and Environmental Hygiene
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:59014a0004541f0060d1d65490257fe7687df3f57917c5439644fb2c8ea8a18eb79dcbbafea780b7286e3f2dab5e1a31af48b807490f8d043526c41d9920e062
• Download URL:
  https://stacks.cdc.gov/view/cdc/187678/cdc_187678_DS1.pdf
• File Type:
  [PDF - 1.77 MB ]