After the Persian Gulf War in 1991, the U.N. Security Council established a special commission to oversee the destruction of Iraq's CBW and ballistic missile stockpiles (UNSCOM).  However, UNSCOM was not entirely successful in routing out and destroying Saddam's WMDs.  In December 1998, UNSCOM closed its ongoing verification center in Baghdad in preparation for the commencement of British and U.S. air strikes against Iraq in retaliation for Saddam's failure to cooperate with UNSCOM.  To date the ongoing bombing campaign has not succeeded in bringing Saddam to commit to the complete destruction of his WMD program in cooperation with international monitoring authorities.

As UNSCOM no longer has a presence in Iraq, an accurate assessment of the current size and scope of Saddam's CBW stockpile is not possible.  However, estimates based on earlier UNSCOM investigations and Iraqi weapons declarations give reason for alarm.

CW
Rough estimates of Iraq's CW stockpile conclude that Iraq may have failed to declare up to 600 metric tons of weaponized and bulk agents, including mustard gas and the nerve agents VX and Sarin.  Thousands of CW munitions remain unaccounted for, including as many as 25,000 rockets and 15,000 artillery shells.  Iraq claims to have halted its CW production schedule, but in the absence of UNSCOM investigators, the Iraqi CW program could have been easily reactivated as Iraq retains the expertise and the facilities to carry out such production.

In addition to furthering their own CW program, Iraqi scientists may have helped the international terrorist Osama bin Laden develop a CW capacity.  An August, 1998 New York Times article (link to article) cites senior administration officials as stating that Iraqi scientists were believed to be aiding the terrorists to develop the nerve agent VX at the pharmaceutical factory in Khartoum that was bombed by the United States in retaliation for the August 7 embassy bombings in Kenya and Tanzania.  Such allegations underscore not only the direct threat from the Iraqi CW program, but the indirect proliferation threat of Iraqi weaponry and know-how falling into the hands of other terrorist groups or rogue nations.

BW
In 1995, Iraq admitted to the existence of an offensive biological warfare capability. (Baghdad had earlier insisted that their BW program was engaged in purely defensive research.)  The Iraqi weapons declaration included 8,500 liters of anthrax, 19,000 of bolutinun toxin and 2,200 of aflatoxin.  In addition to stocks of BW agent, the declaration also included BW munitions - specifically Scud missile warheads and aerial bombs and dispensers - prepared for use in the Gulf War. (Such weapons were never deployed.)  UNSCOM has overseen the destruction of the bulk of Iraq's declared BW stockpile, but commission officials believe Baghdad has vastly understated its BW production.