Sarin gas, the chemical weapon that Syrian Pres. Bashar al-Assad allegedly deployed against rebel neighborhoods in Damascus, is a vicious poison that attacks the central nervous system. Business Insider and the U.S. military report that the chemical has had a dark history since it was invented by German Nazi scientists in 1938.

“Just a fraction of an ounce of this stuff, of sarin, on your skin could potentially be fatal,” said CNN's Dr. Sanjay Gupta in an interview Thursday on "Piers Morgan Tonight." “It can be absorbed across the skin, it can be absorbed into the lungs, across the eyes. It’s pretty gruesome stuff.”

“It is so indiscriminate. It is tasteless. It is odorless. You can’t see it. And, so you don’t even know that you’ve been exposed, necessarily, until you suddenly start to get sick. And then, it starts pretty quickly and can degrade pretty quickly as well," Gupta explained.

The poison is similar chemically to some insecticides. It works by disrupting signals in the nervous system, specifically the chemicals that turn glands and muscles on and off. According to the Centers for Disease Control and Prevention (CDC), exposure can result in a myriad of symptoms, including contracted, pinpoint pupils, foaming at the mouth, muscle rigidity, respiratory difficulty and failure, burning eyes, confusion, drowsiness, weakness, nausea, vomiting and other symptoms of nervous system failure.

Typically symptoms are rapid in onset. The U.S. military Chemical Warfare Weapons Fact Sheet on sarin, "Symptoms of overexposure may occur within minutes or hours, depending upon the dose." At high levels, exposure is almost always fatal.

Scientists in Nazi Germany first synthesized sarin in 1938, intending to use it as a pesticide. After discovering its potency as a human poison, even the Nazis decided it was too vicious a weapon to deploy.

Human Rights Watch reported that Saddam Hussein used sarin gas against Kurdish rebels in Iraq's northern territories in repeated bombardments from 1987 and 1988. An estimated 5,000 men, women and children were killed. Those who sought shelter in basements and other underground areas suffered the worst. Sarin, the most volatile known nerve agent, is heavier than air and flows downward.

In 1995, Japan's Aum Shinrikyo cult synthesized sarin gas and released it in five Tokyo subway cars, killing 13 people, seriously injuring 54 and affecting more than 580. Witnesses described a grisly scene of afflicted commuters lying on train platforms with blood pouring from their noses and mouths.

Then on the night of August 26, survivors from neighborhoods around suburban Damascus said that at around 2:00 a.m., they heard a series of booms, then a hissing sound "like a water tank bursting" or "like opening a Pepsi bottle.”

Thousands in the Syrian rebel areas were sickened and an estimated 1,400 killed by what United Nations inspectors are in the process of confirming was a sarin gas attack.

Watch Sanjay Gupta's interview with Piers Morgan, embedded below via CNN:

[image of broken gas masks via]