Review of Acute Human-Toxicity Estimates for Selected Chemical-Warfare Agents

No reliable acute-exposure1 standards have been established for the particular purpose of protecting soldiers from toxic exposures to chemical warfare (CW) agents. Some human-toxicity estimates are available for the most common CW agents—organophosphorus nerve agents and vesicants; however, most of those estimates were developed for offensive purposes (that is, to kill or incapacitate the enemy) and were intended to be interim values only. Because of the possibility of a chemical attack by a foreign power, the Army's Office of the Surgeon General asked the Army's Chemical Defense Equipment Process Action Team (CDEPAT) to review the toxicity data for the nerve agents GA (tabun), GB(sarin), GD (soman), GF, and VX, and the vesicant agent sulfur mustard (HD) and to establish a set of exposure limits that would be useful in protecting soldiers from toxic exposures to those agents. This report is an independent review of the CDEPAT report to determine the scientific validity of the proposed estimates.Table of ContentsFront MatterSummary1 - Introduction and Background Lethal Effects (LCt50)ECt50 for Threshold EffectsLethal Effects (LCt50)ECt50 for Mild EffectsED50 for Severe EffectsCONCLUSIONS AND RECOMMENDATIONSLethal Effects (LCt50)Lethal Effects (LCt50)ECt50 for Severe EffectsLethal Effects (LD50)CONCLUSIONS AND RECOMMENDATIONSLethal Effects (LCt50)ECt50 for Threshold EffectsECt50 for Severe EffectsLethal Effects (LD50)ED50 for Severe EffectsCONCLUSIONS AND RECOMMENDATIONSLethal Effects (LCt50)ECt50 for Threshold EffectsECt50 for Severe EffectsLethal Effects (LD50)CONCLUSIONS AND RECOMMENDATIONSLethal Effects (LCt50)ECt50 for Severe EffectsECt50 for Threshold EffectsLethal Effects (LCt50)Ect50 for Mild EffectsED50 for Severe EffectsCONCLUSIONS AND RECOMMENDATIONSLethal Effects (LCt50)ECt50 for Severe EffectsLethal Effects (LCt50)ECt50 for Mild EffectsED50 for Severe EffectsCONCLUSIONS AND RECOMMENDATIONSUSE OF LOG-PROBIT ANALYSISUSE OF THE ECT50USE OF CONFIDENCE LIMITSReferencesGlossaryAppendix Offensive Versus Defensive Use of Human-Toxicity Estimates for CW Agents REFERENCE