We have talked to several experts about how to evaluate and investigate such allegations.

What is a chemical weapon?

The Chemical Weapons Convention, which entered into force in 1997 and has been signed by 193 nations, including Ukraine and Russia, lists the associations that countries are prohibited from carrying weapons. The Organization for the Prohibition of Chemical Weapons (OPCW), which implements the convention, divides chemical weapons into four categories:

Choking agents, such as chlorine gas, irritate the nose and throat and cause the lungs to secrete fluid, causing choking. Bubble agents, such as mustard gas, cause life-threatening blisters on the eyes, skin, and respiratory tract. Nervous agents, such as Novichok or sarin, affect the nervous system and are absorbed through the skin and lungs. Blood factors, such as hydrogen cyanide, prevent cells from absorbing oxygen, causing them to suffocate.

In warfare, these chemicals are usually diffused into the air as a gas, vapor, aerosol, powder, or liquid using ammunition such as mortars, mines, missiles, or artillery shells. “Some are designed to disperse very quickly. Some are designed to be more persistent and to stay and serve what we call area denial purposes, somewhat to keep everyone out,” said Jeffrey Knopf, professor of nonproliferation and terrorism studies. in Middlebury. Institute of International Studies in Monterrey, California. A Syrian boy holds an oxygen mask over an infant’s face at a makeshift hospital following a reported gas attack in the rebel-held city of Duma in the eastern Guta district on the outskirts of the Syrian capital, Damascus, on January 22. 2018. (Hasan Mohamed / AFP / Getty Images)
Any chemical agent that can be reused and used to harm people during a collision or violent attack can be a chemical weapon, Knopf says. For example, tear gas in large quantities can be used as a weapon against civilians. Along with biological and nuclear weapons, chemical weapons are being considered weapons of mass destructionwhich are controlled through a series of treaties aimed at preventing nations from acquiring and using them.

When have they been used?

World War I (1914-1918) Chlorine and mustard gas were first used by the warring parties in World War I, mainly on the Western Front, where neither side made a profit through the traditional trench warfare. Seven years after the war, the first international treaty banning chemical weapons, the Geneva Protocol, was signed, although it did not prohibit the production and storage of chemical agents. World War II (1939-1945) Although Nazi Germany had discovered nerve agents, they were not used on the battlefield in Europe. The Nazis, however, used fumigating hydrogen cyanide, or Zyklon B, and other poisonous gases to kill millions of Jews in concentration camps. Japan also used mustard and other poisonous gases in its war with China. Korean and Vietnam Wars (1950-1975) Although technically not a chemical weapon, the incendiary compound known as napalm was used in both wars by US forces with devastating effects, burning large areas and causing severe burns and death. It was also used in World War II. Iraq (1980s) In March 1988, Saddam Hussein’s Iraqi regime used mustard and sarin gas in an attack on the city of Halabja during the Kurdish uprising. Many thousands of civilians are believed to have been killed. Iraq also developed mustard gas and nerve agents in its eight-year war with Iran. Iraq has accused Iran of also using chemical weapons during the war. A Kurd prays over the grave of a relative who was killed in a chemical attack in Halabja in 1988 in the Kurdish city, 300 km northeast of Baghdad, on March 16, 2021. (Shwan Mohammed / AFP / Getty Images)
Japan (1994, 1995) The cult of Doomsday Aum Shinrikyo carried out two sarin gas attacks, one in the Tokyo subway in March 1995 that killed 14 and injured thousands and another in Matsumoto a year earlier that ended eight lives. Syrian Civil War (2011-) Chemical weapons, such as sarin and chlorine, have been used many times during the 11-year civil war. One of the most notorious incidents was a sarin attack in 2013 in the eastern Guta area, near the capital, Damascus. Estimates of the death toll range from several hundred to more than 1,400. It led to a UN inquiry that prompted Bashar al-Assad’s regime to sign the Chemical Weapons Convention, which it has violated several times since. The militant Islamist group ISIS, one of the many groups fighting the Syrian forces, is also suspected of using mustard gas during the war. There have been other isolated cases of nerve agents and chemical weapons used to target individualsincluding according to Russia.

Were chemical weapons used in Mariupol?

Members of the far-right Azov battalion fighting the Ukrainian army said three of its fighters felt dizzy and had difficulty breathing after a drone dropped an explosive device near the steel plant where they were hiding. Some describe a sweet taste in their mouth and seeing white smoke. Most experts say that there is not enough evidence to conclude that the symptoms were the result of a chemical attack. A view shows a factory of the company Azovstal Iron and Steel Works behind buildings that were damaged during the Ukraine-Russia conflict in Mariupol on April 7. (Alexander Ermochenko / Reuters)
Dan Kaszeta, a fellow at the Royal United Services Institute in London and a chemical warfare expert, analyzed reports in thread on Twitter and said there could be other explanations for the kind of symptoms the soldiers described as they were at an industrial site in a city that has been bombed relentlessly for the past month and a half. “There is a lot of room in an industrial environment for conventional or incendiary weapons to cause chemical problems due to fires and explosions,” he wrote. “Also look at the wider environment. Mariupol is a big toxic burn pit right now.” The allegations are difficult to verify without photos or videos from the scene, said Angela Kane, the former UN High Commissioner for Disarmament who oversaw the team investigating the 2013 sarin attack in Guta, Syria. In that investigation, investigators were on the ground within five days of the attack and submitted their final report concluding that sarin was used against civilians, as well as in three other attacks, four months later. CLOCKS Former United States Secretary of Defense Andrew Weber on allegations of chemical weapons use:

It is difficult to determine whether Russia used chemical weapons, says the expert

Although it will be difficult to determine whether Russia dropped a poisonous substance on Mariupol, if chemical weapons are used, they will probably continue to be used in larger quantities, said former US Assistant Secretary of Defense Andrew Weber. 5:27

Why are they used?

Most experts say that the intention of chemical weapons is primarily to terrorize the civilian population psychologically and that they are usually ineffective as a battlefield tactic, especially as most professional soldiers are equipped with equipment to protect them. You can at least have the opportunity to hide from rockets, but you can not hide from the air you breathe. – Prof. Katarzyna Zysk, Norwegian Institute of Defense Studies
“It can be something that can help break the will to resist and the morale,” said Katarzyna Zysk, a professor of international relations and modern history at the Norwegian Institute of Defense Studies in Oslo. “You can at least have a chance to hide from the rockets, but you can not hide from the air you breathe” When used by non-state actors, such as terrorist organizations, chemical weapons can help fighters “gain weight,” he said. In urban settings, they can be a way to speed up the end of a battle and force an opposing party to make concessions, Zysk said. “Civil war is very difficult and often very prolonged because people… can hide in buildings and you have to go to buildings after they are built,” he said. Since the Iran-Iraq war, chemical weapons have been used primarily as counter-insurgency measures against the populations of the states themselves and not other states, Knopf says. A Russian soldier collects weapons found while patrolling the Mariupol theater, which was bombed on March 16 this week in Mariupol. (Alexander Nemenpv / AFP / Getty Images)

Can you protect yourself from them?

Most armies have protective equipment and units that are trained to operate in contaminated environments, Zysk said, but civilians usually do not have such protection. Treatment after exposure to chemical weapons may not always be possible. In the case of certain nerve agents, for example, antidotes should be given within minutes of exposure. The amount and concentration of the chemical also affects how deadly it is. In the Tokyo subway attack, for example, the sarin used was a pure form that evaporates quickly, said Kane, who is now Sam Nunn’s distinguished collaborator in the Nuclear Threat Initiative in Washington, DC. “They had deaths, but they were not as many as one would expect,” he said. In Guta, sarin was cut with another chemical and remained longer, causing more deaths. Passengers on the subway affected by sarin gas planted in Tokyo’s central metro are being transported to St. Paul International Hospital. Luke in Tokyo on March 20, 1995. (Chikumo Chiaki / The Associated Press)

How do you prove that they have been used?

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