On June 9, four days before Israel struck Iran’s nuclear facilities, the Board of Governors of the International Atomic Energy Agency (IAEA) met at its headquarters in Vienna, Austria. The agenda included verification and monitoring the nuclear safeguards in Iran, Syria, Ukraine and North Korea. However, Iran dominated the deliberations as Director-General Rafael Mariano Grossi raised serious concerns about Tehran’s caginess about its growing stockpile of enriched uranium, estimated at over 400 kg. There were also unresolved questions about Tehran’s nuclear programme, as Iran failed to explain the presence of man-made uranium particles at three undeclared sites – Varamin, Marivan and Turquzabad.
Iran sought to sanitise these three locations prior to IAEA’s verification, raising further suspicion about its intentions. “Unless and until Iran assists the agency in resolving the outstanding safeguards issues, the Agency will not be in a position to provide assurance that Iran’s nuclear programme is exclusively peaceful,” Grossi told the board. Iran’s refusal to disclose full information flouted provisions of the Nuclear Non-Proliferation Treaty Safeguards Agreement. Taking into consideration the secretary-general’s revelations and after further deliberations, the UN nuclear watchdog on June 12 formally concluded that Iran was in breach of its nuclear obligations. Iran promptly denied the allegations. It also announced a new enrichment facility would go live soon, which was later identified as Isfahan.
The very next day, on June 13, Israel started bombarding Iran’s nuclear sites claiming the Islamic country was on the verge of developing nuclear weapons. Under the codename Operation Rising Lion, the Israel Defense Forces hit key atomic sites, military installations, and oil fields across Iran. The barrage of drone and missile attacks caused unspecified damage to Iranian nuclear facilities and related installations at Natanz, Isfahan, Karaj, Tehran, and Arak, besides killing a number of top nuclear scientists with the help of Mossad.
The strikes on nuclear sites were unexpected because, despite Iran’s reluctance to come clean about its nuclear programme, there was no concluding evidence showing the country was close to producing N-bombs. However, questions about why Iran was enriching uranium to 60% purity, way above the 3-4% required for civilian energy purposes, were left to interpretation. If uranium is enriched further to 90% purity, it becomes weapons grade. According to Israel, it’s a matter of just a few days to go from 60% to 90%.
The IAEA described Israel’s attacks on Iran’s nuclear facilities as "deeply concerning" and warned that the strikes probably caused radiological and chemical contamination. While it will take some time to know the actual damage on Iran's nuclear sites, the IAEA’s initial assessment caused considerable alarm.
Have Israeli strikes caused radiation leaks? According to the UN agency’s various statements after the Israeli strikes, there is no evidence of any such disaster yet. Also, the agency later clarified that the contamination may be chemical in nature, which means it could be contained locally.
The IAEA confirmed that the underground enrichment halls at the Natanz facility were badly hit, leaving them severely damaged or completely destroyed. It also verified the damage to the soon-to-be-launched nuclear complex at Isfahan, and the centrifuge production facilities in Karaj and Tehran. Natanz was one of the facilities at which Iran was producing uranium enriched up to 60%. The IAEA detected radioactive contamination at the site, but the levels of radioactivity outside remained unchanged and at normal levels. In other words, no radiation risk for the public.
The Arak heavy water reactor was the latest to be hit by Israel. The partially-built reactor was not operating and, hence, reported no radiological effects. The plant at Arak, also known as Khondab, was originally designed to make plutonium, a key component in nuclear weapons. Under a 2015 deal brokered by former US president Barack Obama, it was restructured to reduce its potential to make weapons grade plutonium. Its core was reportedly removed and filled with concrete.
The IAEA says it is waiting for an early opportunity to have physical access to the damaged sites so that it can assess the situation and make informed decisions to mitigate any risks. However, it may not be an easy task. Even if the conflict eases and the agency’s inspectors are able to visit the damaged nuclear facilities, there is no guarantee that Iran’s estimated 400 kg enriched uranium could be accounted for. In theory, the stockpile should be secured under an IAEA seal at an underground facility. However, its whereabouts are unknown and there are concerns that Tehran may attempt to move the stockpile.
The US Nuclear Regulatory Commission defines radioactive contamination as "Undesirable radioactive material (with a potentially harmful effect) that is either airborne or deposited in (or on the surface of) structures, objects, soil, water, or living organisms (people, animals, or plants) in a concentration that may harm people, equipment, or the environment."
Under international law, nuclear facilities can’t be touched even during war. This is because strikes on nuclear sites could release deadly radiation that can kill people or affect their health.
Of the sites that Israel hit so far, the highest risk of radiation may be at the Natanz enrichment facility. Natanz has six above-ground buildings and three underground. The Israeli strikes destroyed the above-ground part of the Pilot Fuel Enrichment Plant, which produced uranium enriched up to 60% purity. No damage was detected in the main Fuel Enrichment Plant located underground. However, the loss of power may have rendered the underground part also ineffective. IAEA has ruled out any radiation outside the site.
Uranium ore in itself is not highly radioactive, but it can be a source of high radiation exposure after enrichment of the fissile isotope uranium-235 (U-235) component. Raw uranium ore has less than 1% U-235 and enrichment is the process to increase its proportion. It is done using centrifuges that spin at extremely high speeds, separating U-235 by removing other impurities. A high percentage of U-235 is needed for manufacturing nuclear weapons but it poses greater danger to human health.
The U-235 isotope and its ‘decay products’ emit three types of radiation – alpha particles, beta particles, and gamma rays. While the first two are relatively harmless – alpha can’t penetrate skin and beta can be stopped by a layer of clothing– gamma rays can penetrate the human body, damage the DNA, and even cause cancer. Only a very thick layer of concrete or lead can stop the highly energetic, penetrating Gamma rays.
The worrisome factor about uranium is that it is highly toxic. Its dust particles in air, food, or water can be dangerous to humans. If ingested, it can produce adverse health effects including damage to the kidneys.
Fortunately, so far, no such exposure has been reported. The IAEA raised concerns about Alpha particles inside the Natanz facility but said they are ‘manageable’ with appropriate radiation protection measures. Only when the conflict ends and the agency’s inspectors can reach the affected sites, can the real dangers be known.