TYPE OF AGENT – Nerve gas

NAME (CHEMICAL) –– Isopropyl methylphosphonofluoridate

NAME (NATO) – GB

NAME (COMMON) – Sarin

DATE OF DISCOVERY – 1938

MOLECULAR FORMULA – C₄H₁₀FO₂P

MOLECULAR WEIGHT – 140.10 g/mol

PHYSICAL STATE @ 20° C. (68° F.)  – Liquid

VAPOR DENSITY (AIR = 1.0) – 4.86

FLASH POINT – Nonflammable

FREEZING/MELTING POINT – -56° C. (69° F.)

BOILING POINT – 147° C. (297° F.)

LIQUID DENSITY – 1.0887 g/cc @ 25° C. (77° F.)

VAPOR PRESSURE (mm/Hg) – 2.2 mm/Hg @ 25° C. (77° F.)

VOLATILITY (mg/m³) – 16,800 mg/m³ @ 25° C. (77° F.)

ODOR – Odorless when pure

APPEARANCE – Clear colorless liquid

SOLUBILITY – Miscible with water

MEDIAN INCAPACITATING DOSAGE (ID50) – 75 mg-min/m³ via inhalation

MEDIAN LETHAL DOSAGE (LD50) – 100 mg-min/m³ for resting men, 70 mg-min/m3 for men engaged in mild activity, Skin Contact – 24 mg per kilogram body weight

PERSISTENCY – Considered a very low persistency agent, vapor remains for minutes to hours, liquid remains for 2 to 24 hours – times dependent on amount of agent present and weather conditions. High temperature, humidity, wind, and moisture reduce persistency

INHALATION TOXICITY – Very high, this is the most toxic route of exposure

SKIN TOXICITY – Very high, does not injure skin but liquid agent very quickly penetrates.

EYE TOXICITY – Very high, much greater toxicity rate than through skin

RATE OF ACTION – Very rapid, death usually within 15 minutes after fatal dose is absorbed

SYMPTOMS (PHYSIOLOGICAL ACTION) – Inhibits breakdown of acetylcholine in the body, interrupting nerve signals, causes contraction of the pupils of the eyes, excessive mucus, tears, saliva, and sweat, nausea, gastrointestinal paid=n, & vomiting, Constriction of the bronchial passages and chest tightness, spasms, convulsions, coma and death.

TREATMENT – Injections of Atropine, Pralidoxime chloride (2-PAMC1), Diazepam, supportive treatment

DURATION OF EFFECTIVENESS – Evaporates at about the same rate as water

PROTECTION – Full gas mask with hood, impermeable clothing and overboots.

DECONTAMINATION – Wash contaminated area down with bleach slurry, dilute alkali

USE – Grenades (German only), Artillery and mortar shells, land mines, aerial bombs, rockets, and spray

     This agent, also first discovered in German pre-World War II, was named after the scientists who first discovered it – Schrader, Ambros, Ritter, and Van der Linde. It was only the second such nerve agent known and was very quickly placed under the purview of the German military. As Tabun was considered, this is one of the most toxic chemicals ever produced by man up to the Second World War and was considered to have the capability of  being an even more effective chemical weapon than the earlier Tabun.

Sarin is one of the few nerve gases to have been used offensively. During the Iran-Iraq conflict in the 1980s, there were several instances of Sarin being used by the Iraqis against the Iranian forces. A large number of nerve gas loaded 122mm rockets were destroyed by US troops in 1991, after Desert Storm had completed. As sarin is relatively easy to manufacture, though the procedures are extremely dangerous, it has appeal to terrorist groups as a possible weapon of mass destruction. Sarin is the only WMD nerve agent to have been used in a terrorist attack.

June 27, 1994, the extremist cult Aum Shinrikyo attacked a residential neighborhood in Matsumoto, Japan, a city 322 kilometers NW of Tokyo. With complete disregard for the safety or lives of the 300,000 people who lived in the city, the cult released a cloud of sarin gas from a computer-controlled release system hidden in a converted refrigerator truck. The target of the attack was the residences of three judges who were involved in a real estate lawsuit against the cult. Seven people were quickly killed in the attack, and five hundred people sent to local hospitals. A second sarin attack was conducted by Aum Shinrikyo less than a year later. On March 20, 1995, conducted a crude sarin attach on the subway system of Tokyo, Japan. Five trains had cult members placed plastic bottles of sarin agent hidden in plastic bags with the bottles wrapped in newspaper. The containers were penetrated with the tip of umbrellas just before the terrorists made their exit from the trains.

     Due to the Aum Shinriko attack, 3,800 people were injured with close to 1,000 people requiring hospitalization. Twelve people were killed by the crudely made and released agent. The facilities of Aum Shinriko were raided within 48 hours of the attack. The means of manufacture of sarin nerve gas were taken by the authorities and the Aum Shinrikyo cult effectively eliminated. What the nerve gas attacks did accomplish was the awakening of governments to the actual possibility of terrorists employing WMDs in the form of chemical weapons. Actions were taken to help minimize that threat.