Quirks & Quarks

A scientific history of chemical weapons

Human Rights Watch has documented 85 chemical weapons attacks in Syria since 2013
A child cries as they have their face wiped following alleged chemical weapons attack, in what is said to be Douma, Syria on April 8, 2018. (White Helmets/Reuters TV)

The first chemical weapon - chlorine gas

In the First World War, after months of gruelling trench warfare, both sides were looking for a breakthrough that might lead to a quick victory. Germany was the first to develop a chemical weapon for use on the battlefield. They first used chlorine gas in the spring of 1915. Chlorine gas inflames the lungs, causing asphyxiation. 

A Russian soldier advances, equipped with full breathing apparatus to protect himself from chlorine gas attack. (Hulton Archive/Getty Images)

Mustard gas causes blistering through clothes

Although not as deadly as chlorine, mustard gas causes severe irritation, burning, and blistering, and makes breathing difficult. It can penetrate clothing. In high enough concentrations, it can even kill. However, symptoms may not appear immediately. It was first used by German forces in the summer of 1917. Unlike chlorine, which has numerous uses in industry, mustard gas was developed specifically as a weapon of war because by then, the Allies knew to use gas masks against chlorine gas. 

British casualities blinded by mustard gas in a German gas attack at Bethune, France. (Three Lions/Getty Images)

Nerve agents developed out of pesticide research

Nerve agents were developed in the 1930s as an outgrowth of the pesticide industry. Nerve agents such as Sarin are invisible and odourless. They react with the body's enzymes, damaging the nervous system; this can cause difficulty breathing, tremors, and vomiting. In high doses, it kills through asphyxiation.

U.S Marines from the 1st U.S Marines Expeditionary Force, NBC, Nuclear, biological and Chemical Incident Response Force conduct a test on 40 veils of suspected Sarin gas that U.S. Marines found while searching an house November 11, 2004 in Fallujah, Iraq. (Marco Di Lauro/Getty Images)

Suspected chemical weapons attack in Douma, Syria on April 7, 2018

During the evening of April 7, 2018, people in the city of Douma, Syria, began showing up at medical centres with symptoms that included breathing problems, convulsions, and foaming at the mouth. According to Dr. Spiers, a professor of strategic studies who specializes in chemical and biological weapons at the University of Leeds, he says these symptoms would be consistent with a nerve agent attack. To be sure of exactly what happened in Douma, scientists would need access to the site -- as of April 20, they are not yet on the scene. The more time that passes before inspectors gain access to the site, the harder it is to identify traces of chemical agents -- but it may still be impossible, Dr. Spiers says.

A man is washed following alleged chemical weapons attack, in what is said to be Douma, Syria in this still image from video obtained by Reuters on April 8, 2018. (White Helmets/Reuters TV/Reuters)