Reactive Oxygen Species and Sulfoxyl Radicals in the Aerobic Decomposition of Thioureas Dioxides

Details

• Personal Author:
  Makarov SV ; Mundoma CM ; Simoyi RH ; Svarovsky SA
• Description:
  Thioureas dioxides (aminoiminomethane sulfinic acids) are stable in acidic and neutral environments, but rapidly decompose in basic medium to produce a variety of products that include sulfur dioxide. A detailed kinetic and mechanistic study of the decomposition of thioureas dioxides in basic medium has shown a process that produces dithionite, S2042-, which is preceded by an induction period which persists for as long as molecular oxygen is present in the reaction solution. The complete consumption of molecular oxygen is a prerequisite for the formation of S2042-. The proposed mechanism involves the initial formation of sulfoxylate ion, SO22-, through heterolytic cleavage of C-S bond. The sulfoxylate ion then reacts with oxygen to produce a series of highly reactive species. Among some of the intermediates detected in the decomposition of thioureas dioxides are the sulfite radical, superoxide, peroxide, and hydroxyl radical. It is suggested that these reactive species are responsible for the toxicity observed in most thioureas. [Description provided by NIOSH]
• Subjects:
  Chemistry Free Radicals Hazardous Substances Occupational Health Safety Sulfur Compounds Thiourea Urea
• Keywords:
  Chemical-deposition Chemical-reactions Free-radical-generation Free-radicals Sulfur-compounds Thioureas Toxic-effects Ureas
• ISSN:
  0065-7727
• Document Type:
  Text
• Genre:
  Abstract or Summary ; Proceedings
• 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:
  218
• NIOSHTIC Number:
  nn:20033637
• Citation:
  Abstr Pap - Am Chem Soc 1999 Aug; 218(Pt 2):U375
• Contact Point Address:
  Reuben H. Simoyi, Department of Chemistry, West Virginia University, P.O. Box 6045, Morgantown, WV 26506
• Email:
  rhsimoy@wvu.edu
• CAS Registry Number:
  Sulfur dioxide (CAS RN 7446-09-5)
• Federal Fiscal Year:
  1999
• Peer Reviewed:
  False
• Part Number:
  2
• Source Full Name:
  Abstracts of Papers - American Chemical Society
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:f5125fd19a0c966d3a8633a22de26f2735b2c631646e228104c833ebca5581c4785d1414006601846cf22701e150b79258e86fd2b56f070405612c0b39f83aea
• Download URL:
  https://stacks.cdc.gov/view/cdc/189123/cdc_189123_DS1.pdf
• File Type:
  [PDF - 238.69 KB ]