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Author
Levin, B. C.
Title
Reduced Toxicity of the Combined Major Fire Gases Produced by the Thermal Decomposition of Wool. Annual Report. Year One.
Coporate
National Institute of Standards and Technology, Gaithersburg, MD
Sponsor
Wool Bureau, Inc, Woodbury, NY International Wool Secretariat, Woodbury, NY
Report
Annual Report, Year One, April 15, 1988, 32 p.
Keywords
wool | toxicity | fire gases | thermal decomposition | acute toxicity | combustion products | hydrogen cyanide | inhalation | animals | blook cyanide
Abstract
The toxicity of wool fibers was studied to determine whether the toxic effects of non-flaming (NF) combustion products could be explained by the 4-Gas model developed at NBS for predicting toxicological interaction of primary fire gases. In this work sponsored by the Wool Bureau and the International Wool Secretariat, Fischer 344 male rats were exposed for 30 minutes to the thermal decomposition products of wool using the standard NBS Toxicity Test Method or a version modified such that the animals were exposed to only steady-state gas concentrations. The toxicity of the combined concentrations of hydrogen cyanide (HCN), carbon monoxide (CO), carbon dioxide (CO2), and reduced oxygen (O2) generated from NF wool at the LC50 values were compared with similar concentrations of combined pure gases. The results indicate that the toxicological interaction of the four gases. Since the predominant toxicant evolved from wool is HCN, blood cyanide concentrations in the blood of animals exposed to wool combustion products were compared to blood cyanide concentrations in animals exposed to equivalent concentrations of mixed gases. Blood cyanide levels were lower in the animals exposed to the wool decomposition products. This indicates that the normally observed toxicity of HCN is reduced when the HCN is produced in conjunction with other combustion products of wool because the blood cyanide concentrations are lower. Future work will be aimed at determining the molecular mechanism for the reduced blood cyanide levels.