Drone Swarms and Chemical-Biological Weapons in Ukraine

Editorial disclosure: this article is based primarily on publicly published analysis by Zachary Kallenborn and Dr. Philipp C. Bleek: "Drones of Mass Destruction: Drone Swarms and the Future of Nuclear, Chemical, and Biological Weapons," War on the Rocks, February 14, 2019. Additional factual context is drawn from OPCW Technical Assistance Visit reports on Ukraine and from NIOSH guidance. Zachary Kallenborn, Philipp C. Bleek, King's College London, the Middlebury Institute of International Studies, War on the Rocks, the OPCW, and NIOSH are not affiliated with CBRNMASKS.COM and have not endorsed the company or any product it offers. Analysis, preparedness conclusions, and product recommendations are by David Magen alone.

The first thing people hear is not an explosion. It is a sound too small for the danger it carries: the thin electric whine of rotors somewhere above the roofs. One drone crosses the street. Then another. A third pauses against the wind as though it is looking for something. There is no pilot overhead, no aircraft large enough to trigger instinctive fear, and no obvious front line separating the attacker from the people below.

Drone Swarms and Chemical-Biological Weapons: What the Evidence From Ukraine Now Shows

For most of the modern era, chemical and biological weapons had a practical weakness. Producing a dangerous agent was only part of the problem. The user still had to deliver it in the right form, at the right concentration, over the right place, without destroying the agent or exposing the operator. Drone swarms may change that equation. That was the warning issued by Zachary Kallenborn and Dr. Philipp C. Bleek in their analysis published in War on the Rocks in February 2019.

This analysis is best read alongside a former NATO CBRN commander on gas masks in Ukraine and AI, drones and synthetic biology as a WMD threat. Together, they connect the threat picture with its operational and civilian-preparedness implications.

Kallenborn studies drone warfare, weapons of mass destruction, and catastrophic security risks in the Department of War Studies at King's College London — the U.S. Army has formally described him as a "Mad Scientist," its term for outside thinkers who challenge conventional military assumptions. Bleek is Professor of Nonproliferation and Terrorism Studies at the Middlebury Institute of International Studies, with expertise in CBRN threats from both states and non-state actors. Their argument was not that every drone would become a flying chemical weapon. It was that swarming technology could remove several obstacles that had historically limited the effectiveness of chemical and biological attacks. A missile delivers one warhead to one point. A swarm can sense, communicate, divide tasks, and adapt while it is already in the air.

The Prediction That Stopped Sounding Theoretical

When Kallenborn and Bleek published their warning in 2019, the image of coordinated drones carrying unconventional payloads still felt futuristic to many readers. The war in Ukraine changed the emotional meaning of the word "drone." Small first-person-view aircraft became routine battlefield instruments — searching for individuals, entering trenches, striking vehicles, and forcing soldiers to treat the open sky as contested terrain. Then chemical evidence appeared beside the wreckage.

In June 2025, the OPCW reported on samples collected after an alleged toxic-chemical incident near a Ukrainian observation position. Two independently operating OPCW-designated laboratories found the riot-control agent CS, or its related compounds, in grenade samples and nearby environmental material. A wipe sample taken from the burned frame of a recovered FPV drone also contained CS at very low levels. The OPCW report did not assign responsibility, did not establish that an autonomous swarm had been used, and did not prove a biological attack or the delivery of a mass-casualty chemical agent. But it placed an FPV drone, chemically contaminated grenades, and a real battlefield incident inside the same official evidentiary record. One drone is not a swarm. CS is not a nerve agent. Yet the distance between the experts' warning and operational reality had clearly narrowed.

The Old Delivery Problem

Chemical and biological agents are not magic dust. Their military effectiveness depends on conditions that can be difficult to control: wind moves, temperature changes, buildings redirect airflow, some biological material is fragile. Traditional delivery systems also announce themselves — aircraft can be detected, artillery exposes launch areas, large missiles are expensive and strategically visible. Kallenborn and Bleek saw drones as a technology that could make delivery more precise, distributed, and adaptive. Sensor-equipped aircraft could observe environmental conditions and communicate them to other members of a swarm. If one route were blocked or one aircraft destroyed, the remaining drones could alter their movement rather than continue blindly toward failure.

Why a Swarm Is More Frightening Than a Larger Bomb

A single large weapon concentrates risk in one object. Stop the missile and the payload may never arrive. A swarm divides the problem into many smaller objects — some drones may carry sensors, others communications equipment, others decoys. The loss of one component does not necessarily end the mission. Defenders must detect, identify, and stop multiple small aircraft that may approach from different directions and at different heights. This creates an asymmetry that favors the attacker: the drone may cost far less than the interceptor used against it.

The darkest possibility is not necessarily one enormous release over an entire city. It is a series of smaller, confusing incidents that force authorities to ask whether the first event was the attack — or only the test. Uncertainty becomes part of the weapon. The attacker controls only the release. Public fear, interrupted services, emergency closures, and the search for additional devices can multiply the impact long after the drone has fallen.

Biological Delivery: The More Silent Fear

The chemical-drone risk has moved closer to documented battlefield reality. The biological-swarm scenario remains far less proven publicly. A chemical irritant can cause immediate coughing, tearing, and panic. A biological aerosol may produce no immediate sensation — people exposed during the release could leave the area feeling normal, and the first evidence might appear when unrelated clinics begin reporting similar illness. There is no public evidence that an autonomous drone swarm has carried out a biological attack. That distinction must remain clear. The reason Kallenborn and Bleek's warning matters is that the technology could make an already difficult attribution problem even harder.

The Warning-Time Problem for Families

A missile alert creates a clock. Even when the available time is painfully short, the population knows that something is coming. A small drone may not produce a public alarm until it is already overhead. A covert biological release may not produce an alarm at all. This changes the practical value of accessibility. Protective equipment stored in a distant room, locked vehicle, or unopened packaging may be irrelevant during a short-warning incident. A family must know where the equipment is, which system belongs to each person, and how it is assembled before the sound of rotors turns an ordinary evening into an emergency. The first question is not "Which mask looks most military?" It is "Can every member of the household actually use the equipment assigned to them?"

Building a Practical Family Respiratory-Protection Kit

Adults: the Israeli 4A1 Black Diamond Simplex is genuine Israeli full-face civil-defense equipment featuring a panoramic visor, 40mm threaded filter connection, hydration tube, and sealed Israeli filter. Full-face coverage matters in a chemical aerosol environment because the eyes may be affected alongside the respiratory system. But the seal is the system's foundation — a beard, damaged sealing surface, incorrect size, or eyeglass arm under the mask can create a route around the filter.

Bearded users: the Israeli Sapphire PAPR hood covers the head rather than sealing around the cheeks and chin, avoiding the facial-hair seal problem entirely. During a short-warning event, discovering that a mask cannot seal is not a recoverable mistake.

Children, ages 2–8: the MAMTAK / Quartz child PAPR hood uses a transparent protective hood connected to a powered blower that delivers filtered airflow. The child can see the parent through the visor. The parent can see whether the child is distressed. Powered airflow reduces the burden of pulling air through a conventional filter. A threat that may arrive with little warning exposes the weakness in plans that protect the adults first and promise to solve the child's equipment later.

Infants and toddlers, ages 0–2: the Multipro infant protection system is designed for the youngest children who cannot use a standard gas mask at all.

Children, ages 8–14: the Israeli 10A1 child gas mask with 40mm Israeli filter and hydration tube.

Filters: CBRNMASKS.COM offers Israeli PA-12 and M80 Type 80 40mm CBRN/NBC filters. Respiratory protection must be selected according to the actual hazard, documented performance, fit, and equipment condition. Air-purifying respirators do not supply oxygen and do not replace shelter, evacuation, decontamination, or medical treatment.

Explore the Israeli CBRN Family Bundle or the complete range at CBRNMASKS.COM.

Protect Your Family

4A1 for adults, Sapphire for beards (or the Riot Control Kit at a lower entry price), MAMTAK / Quartz for ages 2–8, Multipro for infants. Sealed 40mm filters for every mask — also available as 2-pack, 3-pack, or 4-pack for multi-person households. Israeli CBRN Family Bundle for the complete household. CBRNMASKS.COM — Israeli civil-defense equipment, in service since 2009.

Primary Sources

Analysis and preparedness conclusions by David Magen — former Combat Investigation Officer, Doctrine and Training Division, IDF Operations Directorate; former Staff Officer, National Emergency Authority, continuity planning for local authorities, Haifa region. Founder of CBRNMASKS.COM since 2009. Zachary Kallenborn, Philipp C. Bleek, War on the Rocks, and the OPCW are not affiliated with CBRNMASKS.COM and have not endorsed the company or any product it offers.

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