Chemical Agents of Opportunity for Terrorism: TICs & TIMs

Chemical Agents of Opportunity for Terrorism
Training Support Package
Participant Guide
Slide 17
Chemical Agents of Opportunity for Terrorism:
TICs & TIMs
Clinical Effects Based on
Properties of Agent
High
Solubility
Low
Solubility
Onset of
Symptoms
Warning
Properties
Airway
Injury
Rapid
Good
Upper with
irritation
Delayed
Poor
Lower with lung
injury
Module One – Toxic Industrial Gases as Terrorist Threats
17
The anatomic site of injury depends on the water solubility of the substance inhaled.
High water solubility gases tend to have a rapid onset of symptoms and predominantly
affect the upper airways. Low water solubility gases tend to have a delayed onset of
symptoms and predominantly affect the lower airways.
Simplistically, these gases can be separated into their usual effects based on water
solubility. Individual exposure characteristics may modify this, but – when forming a
case definition – these characteristics provide a reliable framework. Exposure to a very
water soluble irritant substance will force someone to flee (if possible) before a sufficient
dose (concentration x duration) reaches the lower airways because of the irritation
caused by it being dissolved in tear film and saliva/mucous of the upper airways. Of
course, these distinctions may not hold true in an overwhelming situation (massive
exposure) or where escape is not possible. At high doses (prolonged exposure or very
high concentrations or both), the distinction between irritation and injury will become
blurred or lost.
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