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Part II: “We attacked them with chemical weapons and they attacked us with chemical weapons”: Iraqi Records and the History of Iran’s Chemical Weapons Program

The second installment of a three-part article addressing the legacy of chemical weapons use in the Iran-Iraq War and Iran’s chemical weapons program. The article focuses on the history of and lingering debate about Iran’s chemical weapons program and allegations of limited battlefield use. Part one of the article focused on the discovery of two caches of chemical munitions inadvertently discovered by rebels in Libya in 2011 and 2012.

When Baʿthist Iraq invaded the Islamic Republic of Iran on September 22, 1980, Iraqi President Saddam Hussein anticipated a rapid military victory in the offensive targeting the neighboring state’s oil-rich and Arab-majority province of Khuzestan. Labeled in Iraqi propaganda as the “whirlwind war” and “Saddam’s Qadisiyyah” (the latter invoking the seventh century victory by the Arab Muslim Army that paved the way for the conquest of the Zoroastrian Sassanian Empire), Saddam expected Iraqi forces would meet little organized resistance from an adversary weakened by the lingering upheavals of the Iranian Revolution and its aftermath. The Iraqi dictator sought to stanch Ayatollah Ruhollah Khomeini’s calls to export Iran’s Islamist revolution to Iraq and beyond, along with asserting Iraq’s military dominance over Iran and its regional rivals. Saddam envisioned a decisive victory in only five days, which would be a day faster than Israel’s victory over Egypt, Syria, and Jordan in the Six-Day War of June 1967. He initiated the conflict using his air force to bomb Iranian targets, a tactic similar in appearance yet considerably less decisive than when employed by Israel against its Arab neighbors in 1967.[1]

After intense fighting, the Iranian border city of Khorramshahr became the first and only major Iranian city to fall to Iraqi forces. However, Iraq’s invasion quickly bogged down into stalemate. Instead of only five days of war, Iran and Iraq settled into nearly eight years of conflict, illustrating the Niccolo Machiavelli quote, “Wars begin when you will, but do not end when you please.”

By early 1982, Iraqi forces were on the defensive. Although Iraq possessed superior weapons, Iran compensated in numbers and zeal. Iranian human-wave attacks, routinely employing unarmed child-soldiers, swarmed Iraqi positions, and pushed Iraqi troops back toward the border. Then, in June 1982, Saddam seized upon Israel’s invasion of Lebanon to give up Iraq’s last toehold of Iranian territory, announcing that Iraq was unilaterally withdrawing to focus on confronting Israeli aggression, and called for a ceasefire.[2]

At this point, Iran’s clerical rulers and military leaders arrived at the consensus position that the defensive war would shift to one of not only toppling Saddam’s regime in Baghdad, but exporting Iran’s revolution, and defending Islam itself. Outbidding Saddam’s symbolic gesture with respect to Israel, Ayatollah Khomeini announced that the “path to Jerusalem was through Karbala.”[3] While this decision to continue the war would prove fateful and costly for both Iran and Iraq, it facilitated an unusual dynamic where the original aggressor, Baʿthist Iraq, became the attacked and status quo party to the conflict virtually overnight. For the remainder of the war, the Islamic Republic of Iran’s pariah status as an outlaw regime that violated diplomatic immunity, took hostages, supported terrorist groups, attacked neutral commerce in the Gulf, mined international waters, and sought to violently export its Islamist revolution to the Middle East helped create an opening for Iraq in international perceptions, if not reality. Thus, Iraqi diplomatic overtures could appeal to international norms, humanitarian sensibilities, and routinely cite efforts of the United Nations to mediate and end the conflict with Iran. However, greater international awareness of and attention to one weapon employed by Iraq could complicate this appearance.

“For Every Harmful Insect, There is an Insecticide”

Even with Iraqi forces back on their own territory and dug-in behind an increasingly complex system of trenches, fortifications, barriers, and moats, Saddam’s regime sought additional means for offsetting Iran’s numerical advantage in manpower that continued to be hurled against Iraqi defenses. Although Iraq’s chemical weapons program pre-dated the outbreak of war with Iran and originated in the early 1970s, the conflict dramatically expanded official interest in it. In the early 1980s, technical cooperation between Iraq and Egypt, which had used chemical weapons in its war in Yemen during the 1960s, was crucial. Egyptian scientists helped their Iraqi counterparts make rapid advances. Many Iraqi chemical weapons scientists also had received their PhDs from the Chemical Warfare Academy in Moscow between 1973 and 1979.[4] Additionally, the generally permissive international export environment at the time helped the Iraqis in acquiring many of the dual-use components and precursors required for the eventual manufacturing of mustard, tabun, and sarin gasses without arousing suspicion. Prior to 1984, Iraq faced no obstacles whatsoever.[5] The Iraqi project leader’s familiarity with the East-German industrial landscape helped Iraqi commercial operations in Europe.[6]

In 1983, Iraq used chemical weapons against Iranian troops for the first time, a development that only escalated through the end of the war in 1988. In February 1984, an Iraqi press release warned, “the invaders should know that for every harmful insect there is an insecticide capable of annihilating it whatever their number and Iraq possess[es] this annihilation insecticide.”[7] At the time and in hindsight, Saddam’s regime offered the rationalization that Iraq’s use of chemical weapons was in response to Iran’s use, a charge that usually followed international condemnation of Iraq’s use of the weapons. In 1988, Iraqi Foreign Minister Tariq Aziz acknowledged Iraq’s chemical warfare, but said, “Iran started its use. We were victims many times, since the early beginning of the conflict.”

Aziz’s official acknowledgement and rationalization, the first of its kind by an Iraqi official speaking to the press, would not be the last. On April 12, 1990, when meeting with a delegation of US congressmen that included Senator Robert Dole, Saddam explained, “We thought about producing [chemical] weapons against Iran only after they attacked us with such weapons in the Muhammara [Khorramshahr] battle. This information was not widely publicized since it was new weaponry and we did not wish to create panic among the armed forces.”[8]

Nevertheless, when a United Nations team visited in March 1986 and offered to investigate Iraqi allegations of Iranian chemical weapons use, Iraqi officials demurred. The investigative report produced by the team for that mission detailed visits with Iraqi prisoners in Iran who explained being mistakenly hit by Iraq’s own mustard gas. However, as will be discussed below, the most persuasive challenge to Iraq’s official narrative comes from the files of its own General Military Intelligence Directorate. Prior to April 1987, it recorded only four Iranian uses of gas on the battlefield, all of which were CS tear gas, with the first instance occurring in 1983, years after the Khorramshahr battle.[9]

Decades later, post-2003 interviews with former Iraqi generals on the subject contain both echoes of official statements and pieces of additional information. As sources, they are as valuable for what they contain as what they do not. Republican Guard Lieutenant General Ra’ad Majid Rashid al-Hamdani stated that “in 1987, the Iranians began using chemical weapons in a limited manner,” while also acknowledging that Iraqi chemical weapons used on the Fao peninsula in 1988 were carried by the wind back over Iraqi lines. With respect to use of poison gas at Halabja, Hamdani claimed limited Iraqi use followed by Iranian retaliation was what transpired, in keeping with the official narrative.[10] Major General Aladdin Hussein Makki Khamas, alternately, claimed to know nothing about chemical weapons, explaining, “I have no first-hand experience, but I know the Iranians also used them.” Khamas was an army artillery commander and suggested that the air force, but not his service branch, may have used chemical weapons.[11]

In contrast, Major General Alwan Hassoun Alwan al-Abousi claimed the Iraqi Air Force never used chemical weapons, even when challenged with internal documents proving it had. He reiterated that “the artillery may have used chemical weapons, but I was in charge of the three main bases, and we never used chemical weapons.”[12] Former Army Chief of Staff and defector to the Iraqi opposition Nizar al-Khazraji appears to speak more candidly on the subject. In an interview with Lebanese journalist Ghassan Sharbil, he explained,

“Yes, the Iranians used chemical weapons in different areas that resulted in casualties on the Iraqi side. However, at that time Iraqi aircraft controlled the skies, so Iran used other means that did not have a big effect. Yes, Iraqis were killed by Iranian chemical weapons, yet the use of these weapons by the Iraqi side was much greater and more developed. I think that chemical weapons were used for the first time in 1984. I do not recall the exact date. I believe Iraq was the first to turn to this weapon.”[13]

As Iraq escalated its use of poison gas on the battlefield, a diplomatically isolated Iran desperately attempted to draw international attention, requesting that the United Nations conduct investigations. In response to these requests, Secretary-General Javier Perez de Cuellar dispatched a team to investigate once in 1984, 1986, and 1987, along with sending three such missions in 1988 alone.

Iran first alleged Iraqi chemical weapons use before the UN on November 3, 1983. Between March 13 and March 19, 1984, the first UN specialist team to visit Iran observed hospital patients suffering with side effects consistent with sulfur mustard gas. Forensic tests on Iraqi aerial bombs determined the Iraqi military had used both mustard and tabun nerve gas. The UN team’s visit to Iran in March 1986 found that Iraqi chemical weapons use was more extensive than in 1984, and that the Iraqi military relied heavy on mustard gas, with some nerve gas used as well. In the case of the latter, both sarin and tabun dissipated faster into the environment, which made it harder for the team visiting later to collect forensic evidence. Between April 29 and May 3, 1987, the UN team visited Iraq for the first time, where it examined patients in a Baghdad military hospital who had been exposed to mustard gas. The team also visited five sites east of Basra claimed to have been subjected to Iranian chemical weapons attack. Iraqi officials alleged Iranian forces had used phosgene and mustard gas in attacks on April 10, 11, and 12, 1987. They also presented the UN team with 130-millimeter artillery shells that they claimed were captured Iranian chemical weapons. After examination, the forensic analysis found no trace of mustard gas nor chemical resistant coating on the munitions. Clearly skeptical of Iraqi allegations of Iranian chemical weapons use as the cause of Iraqi casualties as opposed to Iraq’s own poison gas, the report concluded, “in the absence of conclusive evidence of the weapons used, it could not be determined how the injuries were caused.”

Iraqi chemical warfare escalated dramatically during the final year of the war, which contributed to three UN investigative trips in 1988. The first visit, in April 1988, came in response to competing Iraqi and Iranian allegations of chemical weapons use by the other around Halabja. During this trip, Iraq asked the UN team to investigate a March 30-31 attack on mountain-top positions north of Halabja, in which it claimed Iranian forces fired twenty artillery shells and dropped three bombs containing mustard gas on Iraqi troops. In July 1988, the UN team confirmed increasing Iraqi chemical weapons use, but also returned to Iraq to investigate claims of Iranian chemical weapons use on June 20 and July 1, along with July 10 and July 11. Iraqi officials presented the team with 141 81-millimeter mortar rounds they claimed were a captured Iranian cache. Noting that the rounds were leaking and in generally bad condition, the team’s assessment did not find mustard gas, but did find traces of thiodiglycol, a component in mustard gas, and water present. The report explained, “it is theoretically possible that that grenade and others in the stockpile might by mistake have been filled with the water phase from the synthesis of mustard gas.” With a skeptical eye on Iraqi claims, the report additionally noted that Iraqi officials told the team that the Iraqi military was not equipped with 81-millimeter mortars, but pointed out that the rounds could be fired from 82-millimeter launchers, which were in the Iraqi arsenal. The final UN report, released a day before the end of the war on August 19, 1988, detailed the exposure of Iranian civilians to Iraqi mustard gas bombs and did not contain any further Iraqi allegations of Iranian chemical weapons use.

The Continued Iran-Iraq War of Words: Iranian Statements

On April 3, 1984, Said Rajaie Khorassani, Iran’s Ambassador to the United Nations, announced, that his country was “capable of manufacturing chemical weapons.” He continued to say that, “if the Iraqis repeat their crime, we may consider using them. But we think that to resort to retaliation can only be justified when all other means of preventing Iraq are exhausted and Iraq repeats its crime.” When asked whether it would be “strategically advisable” for Iraq to obtain chemical weapons, he responded, “To have our weapons at this stage or have the capability to produce them in three or four weeks would not make much difference.”

The following year, the Washington Post  reported that “Iran may turn chemical tables on Iraq.” Quoting unnamed officials and citing leaked CIA reports, the article warned that Syria, one of Iran’s few allies, was helping it obtain the required chemicals. Rebuffed by the Soviet Union in its request that it help Iran, Syria facilitated Iranian commercial efforts to obtain the necessary components and technical assistance in Western Europe, especially from West Germany.” Subsequent reporting noted that Syria considered directly transferring its own chemical weapons to Iran, but appeared to have backed away from doing so, at least temporarily. Later in the war, as Iraq’s use of chemical weapons escalated in 1988, Iranian officials made statements similar to those in 1984. Kamal Khorazi, head of Iran’s War Information Ministry, warned that Iranian forces “may be forced” to use chemical weapons in retaliation. Ali Akbar Hashemi-Rafsanjani, spokesman for the Supreme Defense Council, emphasized before Iran’s Majlis that “where and when necessary the Islamic Republic of Iran will be capable of equipping all its forces with chemical weapons.”[14]

 After the end of the war and several years later, in acceding to the Chemical Weapons Convention in 1997, Iran disclosed its prior efforts to build a domestic chemical weapons program. In response to clarification questions from the US government on May 19, 2004, Iran explained that its 20 metric tons of sulfuric mustard and four metric tons of nitrogen mustard were destroyed before the convention entered into force. Both mustard agents were produced in 1987 and 1988 and destroyed between 1990 and 1992, transferred and stored in barrels at two separate facilities over the course of this period. On the question of weaponization, the Iranians emphasized, “With regard to munitions it should be stated that the chemical weapons agents were never weaponized.” The official narrative of the Islamic Republic of Iran maintains that Iran reluctantly pursued a chemical weapons program as a deterrent to Iraq, but that the chemical agents were never weaponized. As the first part of this article has demonstrated, the discovery of not only Iranian 155-millimeter artillery shells, but especially aerial bombs filled with mustard gas in 2011 and 2012 directly challenges the official Iranian claim that chemical agents were never weaponized.

 Former Foreign Minister Mohammad Javad Zarif and Mohammad Reza Alborzi explained in 1999 that when faced with the question of acquisition or nonproliferation, “Iran has had a strong preference for the latter, although was forced once to opt for acquisition, albeit temporarily.” Given Iran’s trade of mustard gas artillery shells and bombs to Libya for naval mines, Scud missiles, or both, Zarif and Alborzi’s reference to nonproliferation seems ironic. Similar to Iranian statements about chemical weapons down to the present day, Zarif and Alborzi reminded readers, “No nation has ever suffered more from chemical weapons” than Iran.[15] This language has matched private written statements from Iranian officials to US officials, stressing that Iran “considers itself the biggest victim of chemical weapons” and “despite being the first victim of extensive application of nerve agent in the world, never produced and stockpiled any nerve agent.” Indeed, an estimated 100,000 Iranians were exposed to Iraqi chemical weapons with nearly 30,000 still undergoing follow-up treatment more than three decades later.[16] That many Iranians were victims of the largest and most extensive use of chemical weapons in the Middle East is an established fact. However, revealingly, Iranian officials have invoked the narrative of victimhood even when its Bashar al-Assad regime ally has used such weapons in Syria. Some observers, while rightly noting the suffering of Iranians from Iraqi chemical weapons, have continued to accept at face value the statements of Iranian officials about chemical weapons and the history of Iran’s own program. While treatment of this subject rightly notes the suffering of Iranian individuals and Iraqi war crimes, it is necessary to separate both from the statements of Iranian officials.

Another ideological component of the Islamic Republic of Iran’s narrative about why it did not employ chemical weapons was a fatwa issued on the subject by Ayatollah Ruhollah Khomeini, which rejected the production and use of chemical weapons and called for protective measures instead. Perceptive observers have noted that the text of the fatwa has never been released. However, this episode has been invoked by Iranian officials with respect to Iran’s nuclear program and ambitions, with the likely intended conclusion being “The Iran-Iraq War episode strongly suggests the Iranian leadership’s aversion to developing chemical and nuclear weapons is deep-rooted and sincere.” Scholarly treatment of the subject has at least in some ways similarly been charitable to the Iranian regime’s point of view, pointing out, “In fact, it has not been established that Iran used chemical weapons in any substantial way,” and explaining that given the research and development time involved, Iran could not have obtained an advanced chemical weapons capability by war’s end.[17] In sharp contrast, the evidence on balance contradicts the former quote on the sincerity of the Iranian leadership’s aversion to chemical weapons, along with the latter explanation for why Iran could not have obtained a chemical weapons capability. Skeptics of the 2003 fatwa against nuclear weapons issued by Ayatollah Ali Khamenei have noticed that the statements of Iranian officials about nuclear weapons have both evolved and been contradictory in way like those on chemical weapons.

Tellingly, US diplomatic records and Iraqi intelligence records both date the beginning of Iran’s chemical weapons program to 1983,[18] the same year Iraq began using chemical weapons against Iran on a large scale.[19] Practically speaking for Iran, there was nothing to be lost militarily, politically, or in the battle for world public opinion by morally rejecting a weapon it did not possess while appealing to longstanding international norms against its use. Given that being subjected to a type of weapon or witnessing its use and effectiveness are usually the motivations for states to obtain it for its own arsenal, it would have been more surprising if Iran did not initiate its own chemical weapons program in response to Iraq’s and its escalating use of chemical weapons against its forces. The next and concluding part of this article will examine what the Iraqi records captured in the 2003 War reveal on Iran’s effort to constitute a chemical weapons program, along with allegations of Iranian use of chemical weapons in the Iran-Iraq War.


[1] Pierre Raxoux, The Iran-Iraq War (Cambridge, Massachusetts: Belknap Press of Harvard University, 2015), 22-23, and Williamson Murray and Kevin M. Woods, The Iran-Iraq War: A Military and Strategic History (New York: Cambridge University Press, 2014), 84-98.

[2] Raxoux, The Iran-Iraq War, 216-217.

[3] Ray Takeyh, “The Iran-Iraq War: A Reassessment,” Middle East Journal, Vol. 64, No. 3 (Summer 2010), 370-372.

[4] Richard L. Russell, “Iraq’s Chemical Weapons Legacy: What Others Might Learn from Saddam,” Middle East Journal, Vol. 59, No. 2 (Spring 2005), 193-194.

[5] See Jonathan B. Tucker, “Trafficking Networks for Chemical Weapons Precursors: Lessons from the Iran-Iraq War of the 1980s,” James Martin Center for Nonproliferation Studies, Occasional Paper No. 13, November 2008, 1-40.

[6] Pesach Malovany, Wars of Modern Babylon: A History of the Iraqi Army from 1921 to 2003 (Lexington, Kentucky: University Press of Kentucky, 2017), 863-864

[7] As quoted in David M. Walker, “‘An agonizing death’: 1980s U.S. policy on Iraqi chemical weapons during the Iran-Iraq War,” The Journal of the Middle East and Africa, Vol. 8, No. 2 (2017), 188.

[8] As quoted in Malovany, Wars of Modern Babylon, 864.

[9] Conflict Records Research Center (CRRC), SH-GMID-D-000-863, “General Military Intelligence Directorate Reports on Iranian Chemical Weapons,” August 1987-July 1988.

[10] Kevin M. Woods, Williamson Murray, Elizabeth A. Nathan, Laila Sabara, and Ana M. Venegas, Saddam’s Generals: Perspectives of the Iran-Iraq War (Alexandria, Virginia: Institute for Defense Analyses, 2011), 47-49.

[11] Ibid., 145.

[12] Ibid., 202-203.

[13] Ghassān Sharbil, al-ʿirāq min ḥarb ilā ḥarb: ṣaddām marra min hunā [Iraq from War to War: Saddam Passed by Here] (Beirut, Lebanon: Riad El-Rayyes Books, 2010), 179.

[14] “Majlis Speaker on Possible Use of Toxic Gas,” FBIS-NES-88-079, April 25, 1988, 64.

[15] Mohammad Javad Zarif and Mohammad Reza Alborzi, “Weapons of Mass Destruction in Iran’s Security Paradigm: The Case of Chemical Weapons,” The Iranian Journal of International Affairs, Vol. 11, No. 4 (1999), 514-516.

[16] Seyed M. Razavi, Payman Salamati, Ali Amini Harandi, and Mostafa Ghanei, “Prevention and Treatment of Respiratory Consequences Induced by Sulfur Mustard in Iranian Casualties,” International Journal of Preventative Medicine, Vol. 4., No. 4 (April 2013), 383-389.

[17] Katariina Simonen, “Chemical Weapons, Ayatollah Khomeini and Islamic Law,” Global Security: Health, Science, and Policy, Vol. 2, No. 1 (2017), 29-31. The latter point can be rejected at face value. The technical know-how for building chemical weapons had been in the region for decades by the 1980s, beginning with Egypt in the 1960s and followed by Syria in the early 1970s. Making mustard gas, a technology in existence since World War I, is considerably less complex than building nuclear weapons.

[18] CRRC, SH-GMID-D-000-579, “General Military Intelligence Directorate Assessments of Iranian Chemical and Nuclear Capabilities, Locations, Structures, and Readiness,” June 1993-January 2002.

[19] For the history of Iraq’s chemical weapons program, which accelerated when it became clear the war with Iran would not end quickly in its favor, see Timothy V. McCarthy and Jonathan B. Tucker, “Saddam’s Toxic Arsenal: Chemical and Biological Weapons in the Gulf Wars,” in Peter R. Lavoy, Scott D. Sagan, and James J. Wirtz (eds.), Planning the Unthinkable: How New Powers Will Use Nuclear, Biological, and Chemical Weapons (Ithaca, New York and London: Cornell University Press, 2000), 47-78, and Chapter 56, “Unconventional Weapons,” in Malovany, Wars of Modern Babylon, 863-886.

About the Author

Michael Brill

Global Fellow;
Ph.D. Candidate, Department of Near Eastern Studies, Princeton University

Michael P. Brill is a Ph.D. candidate in the Department of Near Eastern Studies at Princeton University, where his research focuses on Ba'thist Iraq.

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