

Radiation sickness from the bomb, the document said, would "weaken enemy units from the standpoint of health and inflict losses that would be difficult to explain, possibly producing a psychological effect." Death, it added, might occur "within two to six weeks."

The bomb, 12 feet long and weighing more than a ton, according to the document, could be dropped on areas used by troops, industrial centers, airports, railroad stations, bridges and "any other areas the command decrees."


Now Playing:
  • Now Playing
  • Fire breaks out in San Francisco’s Castro District SF Fire Department
  • Bob Melvin discusses Yusmiero Petit Susan Slusser, The Chronicle
  • How is climate change affecting the Bay Area? SFGATE
  • Hail in Petaluma, Feb. 22 Twitter / @Leeeeeeeeeeeesa
  • Trump discusses removing ICE from California White House
  • Oakland A's manager Bob Melvin on Jake Smolinski San Francisco Chronicle

While Iraq's effort to build a radiological weapon has been known for several years, the 1987 report sheds light on the secret effort. The document was obtained from the Wisconsin Project on Nuclear Arms Control, a private group in Washington that said it acquired it from a U.N. official.

Radiation or radiological weapons, sometimes known as "dirty nukes," are the poor cousins of nuclear arms. Their conventional high explosives scatter highly radioactive materials to poison targets rather than destroying them with blast and heat. Their effects on people can range from radiation sickness to agonizingly slow death, which is why military experts often see them as ethically bankrupt.

"It shows what kind of guy we're dealing with," said Gary Milhollin, the group's director, of Saddam Hussein, the Iraqi leader. The bomb, he added, was "nasty stuff meant to kill people over a long period of time" and thus, he said, "crossed the line into moral barbarism."

It proved to be basically a dud, Milhollin said, and that caused Iraq to scrap the project. The radiation levels were considered too low to achieve the grisly objectives.

The episode nonetheless "shows Iraq's intention" to develop weapons of mass destruction, he added. The official who disclosed the document, Milhollin said,

is "concerned that Saddam @cq is going to get the bomb."

The United Nations rarely discloses documents gathered in Iraq, but David Albright, formerly a nuclear inspector in Iraq, said he had seen the document and did not doubt it was authentic.

He and other experts agreed that the document, which is to be posted on a Web site ( tomorrow, gives away no secrets that could aid weapons development, nor does it give any indication that the project was a resounding failure.

Nuclear experts say that Iraq today has neither programs to develop radiological weapons nor the reactors needed to make radioactive materials for them, and it has no fuel for nuclear arms. The reactor used in making the prototype radiological weapon was bombed during the Gulf War in 1991, and inspectors tried to keep Iraq from resuming its nuclear efforts for years afterward.

But the inspectors are largely gone, and U.S. experts worry that Iraq may be quietly shopping for bomb fuel and parts on the international black market.

"There's growing concern that Iraq is reconstituting its nuclear weapons program and will make steady progress because it knows so much already," said Albright, president of the Institute for Science and International Security, an arms control group in Washington.

Iraq tested its radiological weapon three times in 1987 as it waged a war of attrition against Iran. It considered the radiation bomb a way to cripple enemy forces.

The main flaws of the weapon, the report said, were that its radioactive charges lost strength quickly. The irradiated charge had to be used within a week. Calm weather was also essential.