Potential prevention strategies to reduce the risk of neurotoxicity associated with manganese-containing welding fumes

Details

• Personal Author:
  Afshari A ; Antonini JM ; Chen BT ; Frazer DG ; Jackson M ; Jefferson AM ; Keane MJ ; Lin GX ; McKinney W ; Sriram K ; Stone S
• Description:
  Welding generates complex metal aerosols, inhalation of which is thought to cause Parkinson's disease (PD)-like neurotoxicity, due to the presence of manganese (Mn) in the welding electrodes. As neurological disorders are generally progressive in nature, with latency between insult and appearance of clinical symptoms, a logical approach for workplace safety and health is to prevent adverse exposures. For welding, this can be achieved by minimizing welding fume (WF) generation rate and/or suitably modifying existing welding practices to reduce toxic exposures. Here, we show that by specifically modulating welding voltage, keeping current and shielding gas constant, the fume composition and neurotoxicological properties of WF can be significantly altered. Rats were exposed by whole-body inhalation to filtered air or WF particulates generated by gas-metal arc-stainless steel welding (GMA-SS; 40 mg/m3; 3h/d x 10d) either at 25V (standard/low; LVSS) or at 30V (high; HVSS) voltage. Both conditions produced good weld quality and similar particulate morphology, although aerosols from HVSS welding comprised of a larger fraction of ultrafine particulates that are characteristically considered to be more toxic than their fine counterparts. Exposure to particulates from LVSS welding caused neuroinflammation (increased Ccl2, Tnfa, Nos2; 1.5 - 3.9 fold; P<0.05) and decreased PD-related proteins (Th, Park5, Park7; 18 - 47%; P<0.05) in the dopaminergic brain areas, striatum and midbrain. Paradoxically, exposure to particulates from HVSS welding did not elicit any dopaminergic neurotoxicity. We determined that the lack of neurotoxicity may be a consequence of the reduced solubility of manganese in HVSS fumes. Our findings show promise for modified welding practices as a potential prevention strategy for Mn-related neurotoxicity during welding; however, it warrants additional investigations to determine if such modifications can be suitably adapted at the workplace to avert or reduce neurological risks. [Description provided by NIOSH]
• Subjects:
  Aerosols Animals Biomarkers Chemistry Dust Environmental Exposure Environmental Health Environmental Pollution Hazardous Substances Laboratories Manganese Men Metals Nervous System Nervous System Diseases Occupational Health Preventive Medicine Safety Toxicology Welding Women Workplace

  More +
• Keywords:
  Aerosol-particles Chemical-composition Environmental-exposure Environmental-hazards Environmental-health Exposure-levels Humans Laboratory-animals Manganese-compounds Metal-compounds Metal-dusts Metal-fumes Metallic-compounds Nervous-system-disorders Nervous-system-function Neurotoxicity Preventive-medicine Toxins Welders Work-environment Workers

  More +
• ISSN:
  1096-6080
• 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:
  HELD - Health Effects Laboratory Division
• Topic:
  Workplace Safety & Health
• Location:
  North America
• Volume:
  138
• Issue:
  1
• NIOSHTIC Number:
  nn:20043925
• Citation:
  Toxicologist 2014 Mar; 138(1):367
• CAS Registry Number:
  Manganese (CAS RN 7439-96-5)
• Federal Fiscal Year:
  2014
• NORA Priority Area:
  Manufacturing
• Peer Reviewed:
  False
• Source Full Name:
  The Toxicologist. Society of Toxicology 53rd Annual Meeting and ToxExpo, March 23-27, 2014, Phonex, Arizona
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:7d33295e28aea087afefd552d1dd7b4fc17ee09b4dd89410fcc559811bb7b9ecde1d0cb63213a69cf326f185967e9c720a9043e613911189a6d5c981c1a14cc4
• Download URL:
  https://stacks.cdc.gov/view/cdc/199793/cdc_199793_DS1.pdf
• File Type:
  [PDF - 237.62 KB ]