Biological and Chemical Weapons
Table 3: Medical Characteristics of Chemical Warfare Agents1
Blister AgentsAgents that cause blisters on skin and damage the respiratory tract, mucous membranes, and eyes. | |||||
Name/Symbol | Means of Exposure | Lethal Dosage2 | Rate of Action3 | Effects | Antidotes/ Methods of Treatment |
| Sulfur Mustard (HD) | Skin contact and/or inhalation | Via inhalation: 1,500 LCt50 Via skin exposure: 4,500 LD50 | Delayed (tissue damage occurs within minutes of contact, but clinical effects are not immediately evident)
Effects manifested 2 to 24 hours after exposure | Pain is not immediate. Topical effects occur on the skin (blisters), in airways (coughing, lesions, in rare cases resulting in respiratory failure) and in the eyes (itchiness, burning sensation, possible cornea damage) Nausea and vomiting can also result | Thorough decontamination using water Prevention of infection using antibiotics Application of lotions/ointments to soothe blisters Mustard has no known antidote British-Anti-Lewisite can mitigate some systemic effects of lewisite, though it can itself cause some toxicity. |
| Lewisite (L) | Skin contact and/or inhalation | Via inhalation: 1,300 LCt50
Via skin exposure: greater than 4,500 LD50 | Rapid Pain and irritation occur immediately | Effects are similar to mustard: skin blistering, burning/watery/swollen eyes, upper airway irritation, systemic blood poisoning | |
| Nitrogen Mustard (HN-3)4 | Skin contact and/or inhalation | Via inhalation: 1,500 LCt50
Via skin exposure: 4,500 LD50 | Rapid Rash occurs within one hour; blistering occurs between 6 to12 hours after exposure | Skin blistering, respiratory tract damage | |
| Mustard-Lewisite | Skin contact and/or inhalation | Via inhalation: 1,500 LCt50 Via skin exposure: 10,000 LCt50 | Rapid Stinging sensation occurs immediately; blisters follow hours later | Skin blistering, burning in the eyes, inflamation of respiratory tract | |
| Phosgene-oxime (CX) | Skin contact and/or inhalation | Via inhalation: 3,200 LCt50 Via skin exposure: 25 LD50
| Rapid | Extremely irritating to eyes, skin, and upper respiratory system | |
| |||||
Name/Symbol | Means of Exposure | Lethal Dosage2 | Rate of Action3 | Effects | Antidotes/ Methods of Treatment |
| Tabun (GA) | Skin contact and/or inhalation | Via inhalation: 400 LCt50 Via skin exposure: 1,000 LD50 | Very rapid
Incapacitating effects occur within 1 to 10 minutes; lethal effects occur within 10 to 15 minutes | Effects seen in eyes (contraction of pupils, pain, dim or blurred vision), nose (runny nose), and airways (chest tightness) Nausea and vomiting also possible Twitching/convulsions result when skeletal muscle reached Fluctuations in heart rate Loss of consciousness and seizure activity can occur within one minute of exposue in cases of exposure to high concentration of agent Eventual paralysis, death | 4 steps to management of exposure to nerve agents:
Therapeutic drug options:
Pretreatment option:
|
| Sarin (GB) | Skin contact and/or inhalation | Via inhalation: 100 LCt50
Via skin exposure: 1,700 LD50 | Very rapid
Incapacitating effects occur within 1 to 10 minutes; lethal effects occur within 2 to 15 minutes | ||
| Soman (GD) | Skin contact and/or inhalation | Via inhalation:70 LCt50
Via skin exposure: | Very rapid
Incapacitating effects occur within 1 to 10 minutes; lethal effects occur within 1 to 15 minutes | ||
| VX | Skin contact and/or inhalation | Via inhalation: 50 LCt50
Via skin exposure: | Rapid
Incapacitating effects occur within 1 to 10 minutes; lethal effects occur within 4 to 42 hours | ||
| Novichok 5 agents | Novichok 5 estimated to exceed effectiveness of VX by 5 to 8 times Novichok 7 estimated to exceed effectiveness of soman by 10 times. | Very rapid
| Assumed to be similar to the effects of other nerve agents listed above | Assumed to be similar to treatment methods for other nerve agents listed above | |
Choking AgentsSubstances that damage respiratory tract, causing extensive fluid build-up in the lungs. | |||||
Name/Symbol | Means of Exposure | Lethal Dosage2 | Rate of Action3 | Effects | Antidotes/ Methods of Treatment |
| Chlorine | Inhalation | 3,000 LCt50 | Rapid Lethal effects manifest 30 minutes after exposure | Shortness of breath, irritation of mucous membranes; coughing; tightness of chest Culminates in fluid build-up in lungs leading to fatal choking | No antidote once exposed Individuals should don gas masks and other protective gear to prevent inhalation Medical responses include:
|
| Phosgene (CG) | Inhalation | 3,200 LCt50 | Delayed Asymptomatic period can last up to 24 hours | ||
| Diphosgene (DP) | Inhalation | 3,200 LCt50 | Delayed
Incapacitating and lethal effects felt after 3 or more hours | ||
| Chloropicrin (PS) | Inhalation | 20,000 LCt50 | Variable
Produces tears in seconds; lethal effects felt after 10 minutes | Vomiting, fluid build-up in lungs | |
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Name/Symbol | Means of Exposure | Lethal Dosage2 | Rate of Action3 | Effects | Antidotes/ Methods of Treatment |
| Hydrogen Cyanide (AC) | Inhalation | 2,000 to 5,000 LCt50 | Rapid Exposure to low concentrations causes symptoms in 1 or more hours Exposure to high concentrations causes sudden unconsciousness | Agents inhibit cell respiration; heart and central nervous system are susceptible Cyanogen Chloride also greatly irritates eyes and lungs In moderate cases:
In severe cases:
| Agents are highly volatile; flush eyes with water; remove contaminated clothing; rinse exposed skin with water Antidotes: intravenous administration of sodium nitrite and sodium thiosulfate for detoxification purposes (i.e., to assist body's ability to excrete cyanide from system) Pretreatment under development in the United Kingdom |
| Cyanogen Chloride (CK) | Inhalation | 11,000 LCt50 | Rapid
Lethal concentration produces effects within 15 seconds of exposure; death following within 6 to 8 minutes | ||
| |||||
Name/Symbol | Means of Exposure | Lethal Dosage2 | Rate of Action3 | Effects | Antidotes/ Methods of Treatment |
| Tear Agent 2 (CN) | Inhalation | 7,000 LCt50 | Rapid | Instant pain in eyes and nose; tearing induced; coughing; chest tightness; vomiting if high doses are swallowed or if individual is especially sensitive | Relocate to fresh air Thorough washing of exposed eyes and skin with water Effects generally dissipate within 15 to 30 minutes of departure from contaminated area |
| Tear Agent O (CS) | Inhalation | 61,000 LCt50 | Rapid | ||
| Psychedelic Agent 3 (BZ) | Inhalation | N/A | Rapid
Effects felt within 30 minutes | Induces altered states of consciousness, including hallucinations, stupor, forgetfulness, confusion | |
1. Sources: Central Intelligence Agency, The Chemical and Biological Warfare Threat (Washington, D.C.: Central Intelligence Agency, 1995); Office of Technology Assessment, Proliferation of Weapons of Mass Destruction: Assessing the Risks, OTA-ISC-559 (Washington, D.C.: Government Printing Office, 1993); Valerie Adams, Chemical Warfare, Chemical Disarmament (Indianapolis: Indiana University Press, 1990); Stockholm International Peace Research Institute, The Problem of Chemical and Biological Warfare Volume I The Rise of CB Weapons (New York: Humanities Press, 1971); Chemical Weapons Convention Verification: Handbook on Scheduled Chemicals (August 1993); Gordon Burck and Charles Floweree, International Handbook on Chemical Weapons Proliferation (New York: Greenwood Press, 1991); U.S. Army Center for Health Promotion and Medicine, "Detailed Chemical Fact Sheets," Office to the Deputy for Technical Services, last updated 23 July 1998 [http://chppm-www.apgea.army.mil/dts/dtchemfs.htm]; Iraqi Weapons of Mass Destruction Programs (Washington, D.C.: Central Intelligence Agency, February 1998); Edward M. Spiers, Chemical Warfare (Urbana: University of Illinois Press, 1986); Robert E. Boyle, U.S. Chemical Warfare: A Historical Perspective, (Albuquerque, N.M.: Sandia National Laboratories, August 1998)
2. Approximate median lethal dosage of inhaled airborne agent given in LCt 50 (milligrams per minute per cubic meter, or mg-min/m3), also referred to as lethal concentration time. Approximate median lethal dosage of skin-absorbed agent given in LD 50 (milligrams of agent per kilogram of body weight, or mg agent/kg body weight). The lower the number, the more lethal the agent. (Burck and Floweree)
3. Rate of action refers to how quickly incapacitating effects are felt.
4. In total, three nitrogen mustard agents were developed. The first, HN-1, explored in the late 1920s and early 1930s, was originally designed as a pharmaceutical product. HN-2 followed as a military agent, but later transitioned into the pharmeutical realm. HN-3 was the last of the nitrogen mustards to be developed. These charts focus on HN-3 because its blistering capabilities approach those of sulfur mustard (HD).
5. For more information regarding novichok agents, refer to Vil Mirzayanov's "Dismantling the Soviet/Russian Chemical Weapons Complex: An Insider's View," Chemical Weapons Disarmament in Russia: Problems and Prospects (Washington, D.C.: Henry L. Stimson Center, 1995).
6. Riot control agents listed are a partial representation of existing incapacitating agents. Other agents currently stockpiled around the world for law enforcement purposes can cause vomiting and irritation of the skin, among other symptoms.
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