- A hospital in Douma, Syria, was reportedly attacked with what may be sarin and chlorine gases on Saturday.
- Videos and photos on social media allegedly show dead men, women, and children with others foaming at the mouth and struggling to breathe.
- The suspected gas attacks reportedly killed about 40 to 150 people and injured hundreds of others.
- Sarin gas is a nerve agent that forces the body's muscles into overdrive, leading to convulsions, loss of breathing, and often death.
On Saturday night, barrel bombs filled with chlorine and sarin gases reportedly fell on and near a hospital in Douma, Syria, killing dozens of men, women, and children.
The area is held by rebel forces that oppose the Syrian regime led by Bashar al-Assad, and the timing of the attack came just days after failed negotiations with opposition groups. Al-Assad's regime has also reportedly used chemical weapons since 2013 against rebel-held enclaves packed with civilians.
Syria denied the event ever took place, and — similar to a suspected gas attack in April 2017— its ally Russia reportedly called the event "fabricated" and warned western countries not to retaliate.
However, the US State Department on Monday said the symptoms of victims "reported by credible medical professionals" and those captured in traumatic videos and photos on social media "are consistent with an asphyxiation agent and of a nerve agent of some type,"Reuters reported.
US President Donald Trump tweeted on Sunday that al-Assad will have a "big price to pay" for the alleged attack.
Chlorine gas is a powerful irritant that can wreak havoc on the human body, but isn't known for being extremely lethal. However, it does sink and displace breathable air, so it can asphyxiate people in underground environments.
Just a small amount of sarin gas, however, can be extremely deadly.
Here's what sarin gas is and what it does to the body, according to information from the Centers for Disease Control and Prevention, Reuters, and other sources.
Where the toxin comes from and what it is
Sarin is a nerve agent that:
- Was developed in Germany in 1938 as a pesticide.
- Is a human-made substance that's similar to insecticides called organophosphates, yet is far more powerful.
- Is clear, colorless, tasteless, and odorless liquid in pure form, and dissolves easily in water.
- Rapidly evaporates into a dense gas that sinks to low-lying areas, and is the most volatile of all nerve agents.
- In a bomb, mixes as two chemicals to weaponize the nerve agent.
- Can affect people through their skin, eyes, and lungs, and through contaminated food and clothes.
- Was used in attacks on Japan in 1994 and 1995.
- Was used by Bashar Assad's regime during an attack in Syria in 2013.
Why nerve agents are so deadly
The two following illustrations explain how most nerve agents like sarin affect the body.
To produce these symptoms, nerve agents attack the body's cholinergic system, which is used to transmit signals between the brain and muscle tissues.
The chemicals specifically target an enzyme that drifts in the spaces, or synapses, between nerve cells and muscle cells. There, they persist and constantly trigger muscles into overdrive.
This can paralyze victims, stop their breathing, and trigger convulsions, all of which can lead to death.
This story has been updated. It was originally published at 12:02 a.m. EDT on April 10, 2018.
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