The Effects of Sarin

Posted July 15, 1996

STABILITY OF IRAQ'S CHEMICAL WEAPONS STOCKPILE

Iraq has a sizeable cw stockpile, at least some of which can survive several years of storage. The unitary form of Iraq's s — its principal nerve agent — had a relatively short shelf life during the war with Iran. The Iraqis have been working on this problem: They have tried to increase unitary S shelf life by improving the purity of the precursor chemicals and refining the production processes.

They have developed and tested nerve agent rounds for artillery shells and binary missile warheads as well. CIA believes that by now Iraq has either increased the shelf life of unitary S or produced large quantities of binary munitions

Problems with shelf life

During the war with Iran, Iraq used large quantities of chemical weapons against Iranian ground forces. The principle agents used were the blister agent mustard and the non-persistent nerve agent S. Despite the general sophistication of Iraq's cw production infrastructure, some of Iraq's chemical agents had a short shelf life, mostly owing to impurities in the precursor chemicals. CIA believes that some of the S had a shelf life of only a few weeks. In 1989, the Iraqis destroyed 40 or more tons of S that decomposed.

Efforts to lengthen shelf life

Iraq has attempted to solve the problem in two ways. First, it attempted with foreign assistance, to improve the shelf life of its unitary S by increasing the purity of the precursor and intermediate chemicals and refining production processes. Second it began to develop binary chemical weapons. In a binary munition, the two precursors are stored separately and only mixed to form the chemical agent immediately before or when round is in flight.

Thus, the shelf life of the agent becomes irrelevant; moreover, the munition is safer to handle and store. By 1990, Iraq had successfully tested 155-mm artillery shells and other binary munitions and launched a ballistic missile with a binary warhead as well.

CIA holds that the stocks of S may remain viable well beyond March. CIA analysts believe that the shelf life problem was only temporary and that the Iraqis can now produce unitary agents of sufficient quality by adding a stabilizer or improving the production process.

A Durable Stockpile

Whether or not S stocks remain viable over the long term, all believe that Iraq has a sizeable cw stockpile that is durable enough to survive several years of storage if not destroyed by coalition forces.

We estimate that Iraq had a stockpile of at least 1000 tons of cw agents at the beginning of the conflict with the coalition forces. We believe the principal components of the stockpile are mustard and nerve agents.