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Mustard - Prehospital Management

Acute Management Overview

Agent Identification

  • Sulfur mustards are yellow to brown oily liquids with a slight garlic or mustard odor. Although volatility is low, vapors can reach hazardous levels during warm weather. Sulfur mustards are vesicants causing skin, eye, and respiratory tract injury. Although these agents cause cellular changes within minutes of contact, the onset of pain and other clinical effects are typically delayed for 1 to 24 hours. Sulfur mustards are highly reactive alkylating agents that damage tissues at the point of contact and are also absorbed systemically.
  • Responders should obtain assistance in identifying the chemical(s) from container shapes, placards, labels, shipping papers, and analytical tests. General information on these identification technicques is located in Emergency Response Guidebook.
  • Identification Tools - CHEMM-IST, WISER, Mustard Chemical Properties
  • Devices - M8, M9 chemical agent detector paper (liquid agents), Chemical Agent Detector C2 Kit (liquid and vapor), M18A3 chemical agent detectors (vapor), M256A1 chemical agent detector kit (liquid and vapor), Draeger CDS Kit (vapor and aerosol), Chemical Agent Monitor (CAM) (vapor)
  • A comprehensive source for the selection of chemical identification equipment is the Guide for the Selection of Chemical Detection Equipment for Emergency First Responders, Guide 100-06, January 2007, 3rd Edition published by the Department of Homeland Security to assist with this process.

Rescuer Protection

Mustard Specific Triage

Patients arriving directly from the scene of potential exposure (within 30 - 60 minutes) will rarely have symptoms. The sooner after exposure that symptoms occur, the more likely they are to progress and become severe.

Immediate - mustard casualties, especially those with eye involvement are often classified as immediate for the purposes of decontamination. Immediate decontamination within 2 minutes of exposure can decrease the damage to the tissues. Later decontamination may limit the severity of the lesions. Casualties with liquid mustard burns over 50 % or more of the body surface area or burns of a lesser extent coupled with more than minimal pulmonary involvement (the median lethal dose of liquid mustard will cover about 25 % of the body surface area) have a guarded outcome and will require intensive care for weeks to months (potentially in an aseptic environment).

Delayed - most mustard casualties are generally classified as delayed for both medical attention and decontamination.

Minimal - these casualties have a very small lesion (< 2 % of body surface area in a non-critical area).

Expectant - at less than 4 hours post exposure casualties with burns over 50 % or more of body surface secondary to liquid exposure; lower respiratory signs (dyspnea).

Category (Priority) Time of Onset Clinical Signs
Immediate (1) < 4 up to 12 hours post exposure Lower respiratory signs (dyspnea)
Delayed (2) > 4 hours (eye and skin);
or > 12 hours (respiratory) post exposure
Eye lesions with impaired vision; skin lesion covering 2 to 50 % of body surface area for liquid exposure or any body surface burn for vapor exposure; lower respiratory symptoms (cough with sputum production, dyspnea)
Minimal (3) > 4 hours post exposure Minor eye lesion with no vision impairment; skin lesion < 2 % of body surface area in non-critical areas; minor upper respiratory symptoms (cough, sore throat)


  • Decontamination within 1 or 2 minutes after exposure is the only effective means of decreasing the effects caused by ensuing tissue damage. Patients after the first couple of minutes should still be decontaminated to prevent spread of agent to others.
  • Link to prehospital management section

Route of Exposure

  • Inhalation - Sulfur mustards are readily absorbed from the respiratory tract.
    • Injury develops slowly and intensifies over several days. The vapors are heavier than air. When inhaled, these agents may cause systemic effects.
  • Skin/Eye Contact
    • Mustard vapor and liquid are absorbed through the eyes, skin, and mucous membranes.
    • Skin and eye exposure to vapor sulfur mustard and skin and eye exposure to liquid mustard may cause systemic toxicity.
  • Ingestion - may cause local and systemic effects.

Clinical Signs and Symptoms

Clinical Effects and Time of Onset by Severity of Exposure to Sulfur Mustard

  • The onset of symptoms from inhaled sulfur mustard vapor is generally slow and intensifies over several days. Both local effects at the site of contact and systemic effects from chemical absorption may develop. Clinical effects often do not occur until hours after exposure.
    • Eye: Effects of exposure to blister agents may not appear for an hour or more. Exposure may cause intense eye pain, swelling, lacrimation, and photophobia. High concentrations may cause corneal edema, perforation, blindness and later scarring.
    • Skin: Direct skin exposure to liquid often causes no immediate pain but erythema and blistering may develop. Pruritic rashes occur within 4 to 8 hours followed by blistering 2 to 18 hours later. Moist skin (axilla, groin) is most susceptible to blistering. Direct skin effects following exposure to sulfur mustard vapor is usually less severe than from liquid contact, depending on the extent of contact. Vapor contact often results in first and second degree burns while liquid contact often causes second and third degree burns.
    • Respiratory: Burning nasal pain, epistaxis, sinus pain, laryngitis, loss of taste and smell, cough, wheezing, and dyspnea may occur. Necrosis of respiratory epithelium may cause pseudomembrane formation and airway obstruction. Exposure concentration-dependent inflammatory reactions in the upper and lower airway begin to develop several hours after exposure and progress over several days.
    • Gastrointestinal: Ingestion may cause chemical burns to the GI tract. Nausea and vomiting may occur after ingestion or inhalation.
    • Systemic Effects: Neurological symptoms at high doses include insomnia, hyperexcitability, and convulsions. Hematopoetic effects include bone marrow suppression and an increased risk for fatal complicating infection, hemorrhage and anemia.
  • Link to Toxic Syndromes
  • Link to Primary and Secondary Survey

Differential Diagnosis

  • The delay between exposure and the development of symptoms may present a diagnostic challenge, particularly if the exposure was undetected and the symptoms are mild.
  • A mild exposure affecting the eyes may appear similar to allergic or infectious conjunctivitis or mild eye trauma such as a corneal abrasion.
  • A respiratory vapor exposure may initially mimic allergic rhinitis.
  • Skin exposures may present as burns, which may be attributed to other etiologies, including a scald, or an infectious rash such as staphylococcal scalded skin syndrome.
  • Skin exposure is initially painless with the erythema, skin burning, and pain occuring later. Agents such as lewisite are instantly painful.
  • GI symptoms may be limited to nausea and vomiting which may be consistent with a mild gastroenteritis.
  • Link to Chemical Hazards Emergency Medical Management Intelligent Syndrome Tool (CHEMM-IST)


Acute Patient Care Guidelines References