Methylphosphonyl difluoride (DF), also known as EA-1251 or difluoro, is a
chemical weapon
A chemical weapon (CW) is a specialized munition that uses chemicals formulated to inflict death or harm on humans. According to the Organisation for the Prohibition of Chemical Weapons (OPCW), this can be any chemical compound intended as ...
precursor. Its chemical formula is CH3POF2. It is a Schedule 1 substance under the
Chemical Weapons Convention
The Chemical Weapons Convention (CWC), officially the Convention on the Prohibition of the Development, Production, Stockpiling and Use of Chemical Weapons and on their Destruction, is an arms control treaty administered by the Organisation for ...
. It is used for production of
sarin
Sarin (NATO designation GB nerve_agent#G-series.html" ;"title="hort for nerve agent#G-series">G-series, "B" is an extremely toxic organophosphorus compound.soman as a component of
binary chemical weapon
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Binary chemical weapons or munitions are chemical weapons which contain the toxic agent in its active state as chemical precursors that are significantly less toxic than the agent. This improves the safety of storing, transporting, and ...
artillery
Artillery consists of ranged weapons that launch Ammunition, munitions far beyond the range and power of infantry firearms. Early artillery development focused on the ability to breach defensive walls and fortifications during sieges, and l ...
shell, where it is used together with a mixture of
isopropyl alcohol
Isopropyl alcohol (IUPAC name propan-2-ol and also called isopropanol or 2-propanol) is a colorless, flammable, organic compound with a pungent alcoholic odor.
Isopropyl alcohol, an organic polar molecule, is miscible in water, ethanol, an ...
sarin
Sarin (NATO designation GB nerve_agent#G-series.html" ;"title="hort for nerve agent#G-series">G-series, "B" is an extremely toxic organophosphorus compound.methylphosphonyl dichloride with
hydrogen fluoride
Hydrogen fluoride (fluorane) is an Inorganic chemistry, inorganic compound with chemical formula . It is a very poisonous, colorless gas or liquid that dissolves in water to yield hydrofluoric acid. It is the principal industrial source of fluori ...
(HF) or
sodium fluoride
Sodium fluoride (NaF) is an inorganic compound with the formula . It is a colorless or white solid that is readily soluble in water. It is used in trace amounts in the fluoridation of drinking water to prevent tooth decay, and in toothpastes ...
(NaF).
Safety
Methylphosphonyl difluoride is both reactive and corrosive. It is absorbed through skin and causes burns and mild nerve agent symptoms. It reacts with water, producing HF fumes and methylphosphonic acid as a result. It is also capable of corroding glass.
Significance in international relations
In 2013–2014, the stockpile of chemicals covered by the CWC was removed from Syria and destroyed. Of the stockpile, 581 tons (over 96%) of the stockpile was DF. It was destroyed by the U.S. Army on the MV ''Cape Ray'' by hydrolysis.