Tear Gas (and Pepper Spray)
- Chemical irritant
- Either powder or 1% - 5% aerosol spray
- Commonest used are
- chlorobenzylidene-malononitrile
- (CS after chemists Corson and Stoughton)
- chloroacetophenone (CN or “Mace”)
- dibenzoxazepine (CR)
- oleoresin capsicum (OC)
- pelargonic acid vanillylamide (PAVA)
- chlorobenzylidene-malononitrile
- Pepper strength is measured in Scoville heat units
- Green pepper = 0, pure capsaicin = 15 million units
- Irritant effect from action of chlorine or cyanide groups
- Immediate release of inflammatory P substance
- Effects enhanced by heat and by high humidity
- Rapid onset time & short duration of
effects - Wide margin of safety between the incapacitating dose (ICt 50, the concentration (C) that causes incapacitation (I) in 50% of individuals after one minute (t=time)) and the lethal dose (LCt 50, the concentration that causes death (L) in 50% of individuals after one minute).
Clinical
Area |
Clinical |
Potential complications |
Potential sequelae |
|---|---|---|---|
Eyes |
Tearing, burning sensation, blepharospasm, photophobia, corneal oedema |
Keratitis, corneal erosion, intraocular haemorrhage |
Cataract, glaucoma |
Resp. |
Severe rhinorrhoea, sneeze, cough, dyspnoea, pharyngitis, bronchitis |
Bronchospasm, hypoxia, delayed pulmonary oedema |
Asthma |
CVS |
Hypertension |
Heart failure, cerebral haemorrhage |
|
Skin |
Rash, oedema, erythema, blistering |
Irritant dermatitis, facial oedema |
Allergic dermatitis |
| GIT | Buccal irritation, salivation, abdo. pain, D&V |
Liver toxicity |
|
Neuro |
Trembling, agitation, anxiety |
Management
- Medical teams should wear protection for their own safety and to prevent secondary contamination
- Contaminated clothes removed; eyes and affected skin surfaces should be cleaned with water
- For pulmonary symptoms, oxygen therapy, β2-mimetics and ipratropium aerosols may be required
- For pulmonary symptoms, a 24-48 hour stay in CDU or a discharge home may be required
- Remove contact lenses
- Irrigate eyes with saline or Diphoterine (in storage cupboard, decontamination room CUH)
- Wash skin with soap and water or Diphoterine (in storage cupboard, decontamination room CUH)
- Severe skin lesions - wash then topical steroids
