And here is an excerpt from an article in the Guardian, giving some background on the history of UN weapons inspections in Iraq:

Start quote:

First, there is the history of UN weapons inspections in Iraq from 1991 to 1998. It is true that Iraq has not fully complied with its disarmament obligation, particularly in the field of biological weapons. However, this failure does not equate to a retained biological weapons capability. Far from it. Under the most stringent on-site inspection regime in the history of arms control, Iraq's biological weapons programmes were dismantled, destroyed or rendered harmless during the course of hundreds of no-notice inspections. The major biological weapons production facility - al Hakum, which was responsible for producing Iraq's anthrax - was blown up by high explosive charges and all its equipment destroyed. Other biological facilities met the same fate if it was found that they had, at any time, been used for research and development of biological weapons.

M oreover, Iraq was subjected to intrusive, full-time monitoring of all facilities with a potential biological application. Breweries, animal feed factories, vaccine and drug manufacturing facilities, university research laboratories and all hospitals were subject to constant, repeated inspections. Thousands of swabs and samples were taken from buildings and soil throughout Iraq. No evidence of anthrax or any other biological agent was discovered. While it was impossible to verify that all of Iraq's biological capability had been destroyed, the UN never once found evidence that Iraq had either retained biological weapons or associated production equipment, or was continuing work in the field.

End quote

Link to full article:

http://www.guardian.co.uk/Print/0,3858,4280517,00.html