Table 1—
Chemical Warfare Agents Developed During World War I
| Chlorine (Cl2) | Phosgene: Carbonyl Chloride (COCl2) | Mustard Gas: ββ’-Dichlorethyl Sulfide (ClCH2CH2)2S | Lewisite: β-Chlorovinyldichloroarsine (ClCH=CHAsCl2) | |
| US Army chemical warfare service symbol | Cl | CG | HS | M-1 |
| Physiological classification | Lung injurant | Lung injurant | Vesicant | Vesicant |
| Tactical classification | Casualty agent | Casualty agent | Casualty agent | Casualty agent |
| Vapor density compared with air | 2.5 | 3.5 | 5.5 | 7.1 |
| Persistency | Summer: 5 min in open, 20 min in woods; winter: 10 min in open, 60 min in woods | Summer: 10 min in open 3 min in woods; winter: 20 min in open, 2 h in woods | Summer: 24 h in open, 1 wk in woods; winter: several weeks in both the open and woods | Summer: 24 h in open, 1 wk in woods; winter: 1 wk in the open and woods |
| Lethal concentration, mg/L or oz/1000 cu ft/10 min exposure | 30-min exposure: 2.53; 10-min exposure: 5.60 | 30-min exposure: 0.36; 10-min exposure: 0.50 | 30-min exposure: 0.07; 10-min exposure: 0.15 | 30-min exposure: 0.48; 10-min exposure: 0.12 |
| Odor | Pungent | Fresh-cut hay | Garlic or horseradish | Like geraniums, then biting |
| Neutralization | Alkali solution or solid | Steam will hydrolyze; alkalis and amines react with CG | Bleaching powder 3% solution sodium sulfide (Na2S) in water; steam; gaseous chlorine; or bury under moist earth | Alcoholic sodium hydroxide spray |
| Physiological action | Burns upper respiratory tract | Burns lower lung surfaces causing edema | Dissolves in skin and then produces burns | Dissolves in skin then burns and liberates M-1 oxide, which poisons body |
| Protection | Gas masks, absorbents in canisters only | Gas masks, absorbents in canisters only | Gas masks and protective clothing | Gas masks and best of protective clothing |
| First aid | Keep patient quiet and warm and treat for bronchial pneumonia | Keep patient calm; administer heart stimulants; give oxygen in severe cases, treat like pleurisy | Wash affected parts with kerosene or gasoline, then with strong soap and water; rub, dry, rinse with hot clean water; agent must be removed within 3 min Eye casualty concentration 1 h exposure, .0001 (mg liter). | Wash with oils, hot water, and soap; dry; first aid must be applied at once |
Source. Compiled from Medical Aspects of Chemical and Biological Warfare, ed. Frederick R. Sidell, Ernest T. Takafuji, and David R. Franz (Washington, DC: Office of the Surgeon General; 1997).