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Chemical Attack: Supporting Tables

Table 1. Effects and treatment of some chemical weapons developed for military use


Nerve Agents

Blister Agents (injure skin, eyes, and airways)

Blood Agents (cause blood changes and heart problems)

Choking Agents






Hyrdogen Cyanide

Cyanogen Cyanide





Garlic or Mustard


Burnt Almonds


Mown hay


Non-persistent (min. to hrs.)

Persistent (> 12hrs.)



Non-persistent; Vapors may hang in low areas

Rate of Action

Rapid for vapors; liquid effects may be delayed




Rapid at high concentrations; delayed at lower concentrations

Signs and Symptoms

Headache, runny nose, salivation, pinpointing of pupils, difficulty in breathing, tight chest, seizures, convulsions, nausea, and vomiting

Red, burning skin, blisters, sore throat, dry cough; pulmonary edema, eye damage, nausea, vomiting, diarrhea. Symptoms may be delayed 2 to 24 hrs

Cherry red skin/lips, rapid breathing, dizziness, nausea, vomiting, convulsions, dilated pupils, excessive salivation, gastrointestinal hemorrhage, pulmonary edema,respiratory arrest

Eye and airway irritation, dizziness, tightness in chest, pulmonary edema, painful cough, nausea, headache

First Aid

Remove from area, treat symptomatically, Atropine and pralidoxime chloride (2-PAM chloride), diazepam for seizure control

Decontaminate with copious amount of water, remove clothing, support airway, treat symptomatically

Remove from area, assist ventilations, treat symptomatically, administer cyanide kit

Remove from area, remove contaminated clothing, assist ventilations, rest


Remove from area, remove clothing, flush with soap and water, aerate

* How long a chemical remains at toxic levels

Table 2. Varying toxicity of chemicals

The more toxic a chemical, the smaller the amount of chemical required to cause harm. This table compares the lethal concentrations in parts per million (ppm) for acute (all-at-once) exposures to some chemical weapons and some common industrial chemicals.

Chemical Agent Approx. Lethal Concentration* (in ppm)
Some chemical weapons
Sarin (GB) 36
Hydrogen Cyanide** 120
Some industrial chemicals
Chlorine** 293
Hydrogen chloride 3,000
Carbon monoxide 4,000
Ammonia 16,000
Chloroform 20,000
Vinyl chloride 100,000
*Based on LC50 values in laboratory rats: exposure concentration for 60 minutes at which 50% of rats would die. Rats are used for toxicology tests in part because of similarity to humans, but they are likely to be more susceptible because they have higher metabolisms.
**Used both as chemical weapons and as industrial chemicals
Source: NRC, EPA, and ATSDR
Last Published Date: August 9, 2012
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