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Incendiary Chemical-Warfare Agents and Hydrogen Fluoride (HF)


James M. Madsen

, MD, MPH, University of Florida

Reviewed/Revised Jan 2023

Military incendiary agents are designed to illuminate the battlefield, to start fires, to create smoke to obscure terrain and personnel, or for combinations of these effects. Agents include thickened gasoline (napalm), thermite (TH), white phosphorus (WP), and magnesium. They have physical effects (eg, burns) rather than the primarily chemical effects of chemical-warfare agents Overview of Chemical-Warfare Agents Chemical-warfare (CW) agents are chemical mass-casualty weapons (MCWs) developed by governments for wartime use and include Toxic agents (intended to cause serious injury or death) Incapacitating... read more .

Hydrofluoric acid (HF), used in industry and in other applications, is often confused with hydrochloric acid; for this reason, it is recommended that it be referred to as HF. Any of these compounds can create mass casualties.

Napalm has a jelly-like consistency; the other incendiary agents are usually weaponized as powdered solids. HF can exist at ambient temperatures as a liquid or a vapor. The most common routes of exposure are percutaneous, ocular, and inhalational.


Incendiary agents cause thermal burns. Some of them may be used in exploding projectiles which cause shrapnel that may lodge in tissue. White phosphorus may continue to burn on skin or clothing as long as it has access to air, and because magnesium will burn under water, it will continue to burn within tissue. White phosphorus is toxic and may also cause systemic effects, due to uncoupling of oxidative phosphorylation in hepatocytes, hyperphosphatemia, hypocalcemia (from binding of calcium to phosphorus), renal injury, and hyperkalemia (from hypocalcemia or from renal damage).

HF penetrates deeply and quickly into exposed tissue but generates hydronium ions relatively slowly. The fluoride released from the dissociation of hydrogen fluoride binds avidly to calcium and magnesium. This binding, particularly the binding to calcium, produces severe local pain and may produce systemic effects due to hypocalcemia, hypomagnesemia, and hyperkalemia; coagulopathy and fatal cardiac arrhythmias may occur.

Symptoms and Signs

The onset of pain after HF exposure depends on the concentration of HF; pain may appear within an hour but typically occurs after 2 or 3 hours. However, once pain occurs, it is often deep and intense. Affected skin is erythematous but does not seem as severely affected as the intense pain would suggest.


  • Clinical evaluation

Most incendiary burns are readily apparent. However, burns due to low concentrations of HF may appear deceptively innocuous, and a high index of suspicion must be maintained for deep tissue injury and systemic toxicity. WP burns may glow or smoke when exposed to air.


HF burns should be triaged more urgently than their appearance would otherwise indicate; patients with large areas of exposure should be triaged immediate because of the danger of systemic toxicity.


  • Treat as thermal burns

  • For HF, topical and sometimes systemic calcium

For WP burns, the affected areas are flooded with water or smothered to avoid exposure to air. WP particles are removed mechanically (they often adhere tightly to skin) and placed in water. Smoking trails may be good indicators of the location of small particles. A bicarbonate solution may be used to flood the burns and to wet the burn dressings, but cupric sulfate (CuSO4) is no longer recommended for these burns.

Magnesium reacts with water to generate highly flammable gas and with carbon dioxide to produce magnesium oxide and carbon. Burning or smoking magnesium particles in the skin or subcutis should be removed as promptly as possible. If not all particles can be removed at once (eg, because of the number of wounds), oil can be used to cover wounds until removal can be accomplished.

Patients exposed to HF require prompt decontamination by copious flushing with water; a topical skin decontamination product (Reactive Skin Decontamination Lotion, or RSDL®) has not been tested in patients with skin exposures to HF. However, because HF penetrates quickly, significant local and systemic effects may occur even after thorough decontamination. Calcium gluconate or calcium carbonate paste is applied to local burns. Sometimes local injection of 10% Ca gluconate is also given; some clinicians give Ca gluconate intra-arterially. Patients with significant exposure are hospitalized to undergo cardiac monitoring and treatment with CaCl or Ca gluconate (see table Symptoms and Treatment of Specific Poisons Symptoms and Treatment of Specific Poisons Symptoms and Treatment of Specific Poisons ).

The views expressed in this chapter are those of the author and do not reflect the official policy of the Department of Army, Department of Defense, or the US Government.

Drugs Mentioned In This Article

Drug Name Select Trade
No brand name available
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NOTE: This is the Professional Version. CONSUMERS: View Consumer Version
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