O-Ethyl methylphosphonothioic acid (EMPTA) is an organophosphate compound. A dual-use chemical, it has constructive uses in the synthesis of pesticides and pharmaceuticals, and it is also a precursor in the synthesis of nerve agents such as Agent VM

VM (nerve agent)

VM is a "V-series" nerve agent closely related to the better-known VX nerve agent.Like most of the agents in the V-series , VM has not been extensively studied outside of military science...

 and Agent VX

VX (nerve agent)

VX, IUPAC name O-ethyl S-[2-ethyl] methylphosphonothioate, is an extremely toxic substance whose only application is in chemical warfare as a nerve agent. As a chemical weapon, it is classified as a weapon of mass destruction by the United Nations in UN Resolution 687...

. The detection of EMPTA is cited as a major influence in the United States' 1998 decision to destroy the Al-Shifa pharmaceutical factory

Al-Shifa pharmaceutical factory

The Al-Shifa pharmaceutical factory in Khartoum North, Sudan, was constructed between 1992 and 1996 with components imported from the United States, Sweden, Italy, Switzerland, Germany, India, and Thailand....

in Sudan.