Radiological risks in the Red Sea, Strait of Hormuz

Solly Rakgomo | Monday September 7, 2026 06:00

However, the focus on the Red Sea and Bab-el-Mandeb Strait mainly concerns conventional threats, such as anti-ship ballistic missiles, one-way attack drones, and waterborne explosive devices used by Houthi forces. Yet a lesser-discussed risk exists, one major risk is diverting commercial radioactive material for use in a Radiological Dispersal Device, or dirty bomb.

Radiological Risk in Maritime TransportThe International Atomic Energy Agency (IAEA) classifies radioactive sources into five categories based on the potential harm they could cause if left unshielded. Category 1 and 2 sources, elements such as cobalt-60 and cesium-137 used in cancer treatment and industrial irradiators, could kill someone within minutes to hours of exposure. According to a U.S. Government Accountability Office analysis of Countering Weapons of Mass Destruction (CWMD) risk assessments, Category 3 sources, commonly found in industrial gauges and well-logging equipment, are actually more likely to end up in a dirty bomb than Category 1 or 2 material. Not because they’re more dangerous, but because there are so many of them in ordinary commercial use, and the security around them is lighter.

The key concern, according to the International Atomic Energy Agency therefore, is not access to weapons-grade material but the possible misuse of legitimately used radioactive sources. From a security perspective, the consequences of such an incident could extend well beyond radiation exposure, potentially causing public panic, temporary disruption of affected areas, major economic losses, and costly decontamination operations. This disruption would result not from direct casualties but from strict international regulations and frameworks that require the immediate quarantine of any area with elevated radiation levels. Consequently, an attack targeting critical regional transport nodes would weaponise public anxiety to effectively paralyse maritime operations, transforming localised contamination into an indefinite, multi-billion-dollar trade bottleneck.

These sources are transported legally through the Red Sea corridor, including radiography equipment, well-logging tools, and medical isotopes destined for hospitals and industrial facilities across Africa and the Middle East. That ordinary traffic is exactly what creates the opportunity for smugglers.

In the Strait of Hormuz, Iran’s fast-attack vessels pose significant risks to maritime navigation. The ongoing conflict has escalated this threat into open hostilities, involving the placement of mines and direct attacks on tankers.

In addition, Mahamoud Abdi says that Houthi attacks on commercial shipping in the Red Sea have created a parallel security challenge, forcing vessels to reroute and increasing pressure on maritime-security forces.

The volatility of this environment makes the seizure of such radioactive materials a starkly real possibility. He avers that even if no party deliberately attempts to get these radioactive materials for a planned attack, a conventional missile or mine hitting a standard commercial vessel carrying legal Category 3 cargo could breach its containment hulls.

This would spill radioactive material directly into open waters or vital harbor shipping lanes, creating localised environmental hazards and forcing immediate, long-term closures of strategic maritime routes due to contamination fears. These developments demonstrate how security pressures in the Gulf and the Horn of Africa can interact and compound vulnerabilities across interconnected maritime routes.

Potential Diversion

Vulnerability and ConsequencesResearch into sanctions evasion has documented a so-called dark fleet of tankers, predominantly transporting Russian and Iranian oil and liquefied natural gas (LNG), that manipulate or deactivate their automatic identification system (AIS) transponders and follow irregular and complex ownership structures and routes to conceal their activity and destination details.

Coupled with the dhow smuggling routes between Yemen and the Somali coast, monitored by UN authorities over several years as channels for arms delivery to Houthi forces, these networks could just as readily facilitate the movement of a stolen radioactive source as weapons.

If a ship carrying legally declared Category 3 material were boarded, disabled, or hit, its cargo could vanish before anyone could establish a perimeter, especially since coast guards and coalition ships are already strained by the Hormuz crisis. Adding naval mines and loitering munitions in shallow, crowded waters raises the chances of a hull breach that could release radioactive cargo into a port or fishing area.

Regarding the Red Sea specifically, the genuine threat does not lie in the possibility of Houthi-affiliated groups attempting to develop nuclear weapons. Such an endeavor necessitates resources and expertise that no non-state actor in the region currently possesses.

The credible threat involves Houthi-affiliated groups, or other criminal networks operating within the same domain or zone, gaining access to an unsecured Category 1 to 3 radioactive source via channels already used for trafficking other illicit items.

While the integration of radiological materials into maritime weaponry by Houthi forces remains an unverified capability, the operational motive and territorial precedents within the Yemeni conflict zone are well-established. Security assessments have long flagged the vulnerability of Yemen’s domestic infrastructure. The integration of such materials into naval mines or drone payloads would represent a significant development, signifying a shift from traditional sea-denial weaponry to the deliberate use of radiological contamination.

A radiological dispersal device detonated at key logistic regional hubs such as Djibouti or Jeddah would likely not result in a substantial number of fatalities directly attributable to radiation exposure. However, Djibouti serves as the operational logistics hub for foreign naval coalitions protecting the Bab-el-Mandeb and operating in the Red Sea, while Jeddah represents Saudi Arabia’s primary economic gateway on the Red Sea.

Targeting these mega-terminals allows asymmetric actors to simultaneously disrupt U.S. military support and operations in the region, and inflict severe regional pressure. Consequently, it could nonetheless compel operators to suspend terminal operations for an extended period due to decontamination procedures, incurring costs to shipping, insurance, and regional commerce amounting to billions.

Recommendations for

Radiological Maritime SecurityMaritime security in the region remains predominantly focused on intercepting missiles and drones. There is limited insight into the actual movement of radioactive materials. The following three measures could help improve the current response to the crisis:

l Expand radiation detection capabilities to smaller and informal ports.

l Enhance due diligence concerning the logistics of radioactive sources. Shipping and logistics companies operating in higher-risk jurisdictions should verify the recipients of Category 1 to 3 materials.

l Incorporate radiological threat scenarios into existing crisis planning. The Combined Maritime Forces, via Combined Task Force 153 in coordination with Operation Prosperity Guardian (a U.S.-led multinational coalition established to protect merchant shipping and counter asymmetric attacks in the Red Sea) should incorporate defensive scenarios involving a radiological dispersal device (dirty bomb) into their maritime frameworks and joint exercises.

The Red Sea and the Strait of Hormuz can no longer be evaluated solely in terms of missile, drone, or cyber risks. This conflict has already demonstrated that disruptions at one strategic chokepoint can spread to others.