Chemical Agent Information

Stockpiled Chemical Warfare Agents

Armies first used modern chemical weapons during World War I. Many countries have since developed more-potent chemical agents with more-effective delivery systems. Stockpiles of chemical warfare agents have also grown.

By the early 1960s in the United States alone, the total chemical warfare agent stockpile was estimated at nearly 40,000 tons.

In the United States these chemical warfare agents were stored at nine sites. They were stored in bulk containers or in assembled weapons and ammunition that have since become obsolete. The chemical warfare agents stored at U.S. sites include nerve agents and vesicant, or blister agents.

Nerve Agents

• GA - Tabun or ethyl N,N-dimethyl phosphoroamidocyanidate, CAS 77-81-6
• GB - Sarin or isopropyl methylphosphonofluoridate, CAS 107-44-8
• VX - O-ethyl-S-(2-diisopropylaminoethyl)-methyl phosphonothiolate, CAS 50782-69-9

Vesicant, or Blister Agents

• H, HD - Sulfur mustard, bis-(2-chloroethyl)sulfide, or di-2-chloroethyl sulfide (HD), CAS 505-60-2
• HT - bis(2-chloroethylthioethyl) ether (HT), CAS 63918-89-8
• L - Lewisite or dichloro 2-chlorovinylarsine, CAS 541-25-3

Nonstockpiled Chemical Warfare Agents

Nonstockpiled chemical warfare agents vary. They include

• Former chemical weapons production facilities.
• Recovered chemical weapons and training material.
• Miscellaneous equipment (e.g., empty aerial spray tanks, MT ton containers)

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