Chloropicrin
Encyclopedia
Chloropicrin, also known as PS, is a chemical compound
with the structural formula Cl3CNO2. This colourless highly toxic liquid was once used in chemical warfare
and is currently used as a fumigant and nematocide.
chemist John Stenhouse
. He prepared it by the reaction of a chlorinating agent
with picric acid
:
Because of the precursor he used, Stenhouse named the compound chloropicrin, although the two compounds are structurally dissimilar.
Arguably, chloropicrin's most famous use was in World War I
. In 1917, there were reports that the Germans were testing and using a new chemical in warfare. That chemical was chloropicrin. While not as lethal as other chemical weapons, it caused vomiting
and was a lachrymatory agent
. This combination of properties forced Allied soldiers to remove their masks to vomit, exposing them to toxic gases. This caused a large number of casualties on the Italian front.
with sodium hypochlorite:
and mustard gas in persistency, although closer to phosgene because it is related to the compound. Tests have shown that chloropicrin causes humans to shut their eyes involuntarily. Chloropicrin can be absorbed systemically through inhalation, ingestion, and the skin. It is severely irritating to the lungs, eyes, and skin. Because of these properties, chloropicrin can only be delivered in shell form as a chemical weapon.
, for increased potency and as a warning agent.
Chloropicrin has been used in chemical warfare
. It first appeared in 1917 when the Germans tested a new chemical weapon on the Italian front. The new chemical weapon was devastating to the Allies at first, since they had never encountered it before.
NIOSH 1995 states that:
Examples of industrial exposure in humans: 27 workers in a cellulose factory who were exposed to high levels of chloropicrin for 3 minutes developed pneumonitis
after 3 to 12 hours of irritated coughing and difficulty on breathing; they subsequently developed pulmonary oedema, and one died.
EU classification of chloropicrin is:
R22 Harmful if swallowed, R26 Very toxic by inhalation, R36/37/38 Irritating to eyes, skin and respiratory system, R43 May cause sensitisation by skin contact, R50/53 Very toxic to aquatic organisms, may cause long term adverse effects in the aquatic environment.
Because of chloropicrin's stability, protection requires highly effective absorbents, such as activated charcoal. Chloropicrin, unlike its relative compound phosgene
, is absorbed readily at any temperature, which may pose a threat in low or high temperature climates.
The use of the substance has been restricted by the U.S. government
, although such restriction is outdated now
, detectives Joe Friday (Dan Aykroyd
) and Pep Streebeck (Tom Hanks
) thwart an attempt by mad cultists to release a tanker truck of trichloronitromethane at a party attended by several prominent Los Angeles city officials.
The effects cited in explaining the substance (vomiting, suffocation, and death) are consistent with the actual chemical.
Chemical compound
A chemical compound is a pure chemical substance consisting of two or more different chemical elements that can be separated into simpler substances by chemical reactions. Chemical compounds have a unique and defined chemical structure; they consist of a fixed ratio of atoms that are held together...
with the structural formula Cl3CNO2. This colourless highly toxic liquid was once used in chemical warfare
Chemical warfare
Chemical warfare involves using the toxic properties of chemical substances as weapons. This type of warfare is distinct from Nuclear warfare and Biological warfare, which together make up NBC, the military acronym for Nuclear, Biological, and Chemical...
and is currently used as a fumigant and nematocide.
History
Chloropicrin was first discovered in 1848 by a ScottishScottish people
The Scottish people , or Scots, are a nation and ethnic group native to Scotland. Historically they emerged from an amalgamation of the Picts and Gaels, incorporating neighbouring Britons to the south as well as invading Germanic peoples such as the Anglo-Saxons and the Norse.In modern use,...
chemist John Stenhouse
John Stenhouse
John Stenhouse FRS FRSE FIC FCS was a Scottish chemist. In 1854, he invented one of the first practical respirators.He was a co-founder of the Chemical Society in 1841.-Life:...
. He prepared it by the reaction of a chlorinating agent
Chlorine
Chlorine is the chemical element with atomic number 17 and symbol Cl. It is the second lightest halogen, found in the periodic table in group 17. The element forms diatomic molecules under standard conditions, called dichlorine...
with picric acid
Picric acid
Picric acid is the chemical compound formally called 2,4,6-trinitrophenol . This yellow crystalline solid is one of the most acidic phenols. Like other highly nitrated compounds such as TNT, picric acid is an explosive...
:
- HOC6H2(NO2)3 + 11 NaOCl → 3 Cl3CNO2 + 3 Na2CO3 + 3 NaOH + 2 NaCl
Because of the precursor he used, Stenhouse named the compound chloropicrin, although the two compounds are structurally dissimilar.
Arguably, chloropicrin's most famous use was in World War I
World War I
World War I , which was predominantly called the World War or the Great War from its occurrence until 1939, and the First World War or World War I thereafter, was a major war centred in Europe that began on 28 July 1914 and lasted until 11 November 1918...
. In 1917, there were reports that the Germans were testing and using a new chemical in warfare. That chemical was chloropicrin. While not as lethal as other chemical weapons, it caused vomiting
Vomiting
Vomiting is the forceful expulsion of the contents of one's stomach through the mouth and sometimes the nose...
and was a lachrymatory agent
Lachrymatory agent
Tear gas, formally known as a lachrymatory agent or lachrymator , is a non-lethal chemical weapon that stimulates the corneal nerves in the eyes to cause tears, pain, and even blindness...
. This combination of properties forced Allied soldiers to remove their masks to vomit, exposing them to toxic gases. This caused a large number of casualties on the Italian front.
Preparation
Chloropicrin is manufactured by the reaction of nitromethaneNitromethane
Nitromethane is an organic compound with the chemical formula . It is the simplest organic nitro compound. It is a slightly viscous, highly polar liquid commonly used as a solvent in a variety of industrial applications such as in extractions, as a reaction medium, and as a cleaning solvent...
with sodium hypochlorite:
- H3CNO2 + 3 NaOCl → Cl3CNO2 + 3 NaOH
Properties
As listed in the Table, chloropicrin is a colorless liquid that is insoluble in water, with which it is stable. With a vapor pressure of 24 mm Hg, its volatility is between that of phosgenePhosgene
Phosgene is the chemical compound with the formula COCl2. This colorless gas gained infamy as a chemical weapon during World War I. It is also a valued industrial reagent and building block in synthesis of pharmaceuticals and other organic compounds. In low concentrations, its odor resembles...
and mustard gas in persistency, although closer to phosgene because it is related to the compound. Tests have shown that chloropicrin causes humans to shut their eyes involuntarily. Chloropicrin can be absorbed systemically through inhalation, ingestion, and the skin. It is severely irritating to the lungs, eyes, and skin. Because of these properties, chloropicrin can only be delivered in shell form as a chemical weapon.
Application
Chloropicrin, today, is used as a fumigant to control pests found in the soil. Although less common, it can be used as a poison for vertebrates, such as rabbits. Chloropicrin is commonly used in combination with other fumigants, such as methyl bromide and sulfuryl fluorideSulfuryl fluoride
Sulfuryl fluoride is the inorganic compound with the formula SO2F2. This easily condensed gas has properties more similar to sulfur hexafluoride than sulfuryl chloride, being resistant to hydrolysis even up to 150 °C...
, for increased potency and as a warning agent.
Chloropicrin has been used in chemical warfare
Chemical warfare
Chemical warfare involves using the toxic properties of chemical substances as weapons. This type of warfare is distinct from Nuclear warfare and Biological warfare, which together make up NBC, the military acronym for Nuclear, Biological, and Chemical...
. It first appeared in 1917 when the Germans tested a new chemical weapon on the Italian front. The new chemical weapon was devastating to the Allies at first, since they had never encountered it before.
Safety
Chloropicrin is a highly toxic chemical:NIOSH 1995 states that:
- Chloropicrin is a lacrimator and a severe irritant of the respiratory system in humans; it also causes severe skin irritation on contact. When splashed onto the eye chloropicrin has caused corneal oedema and liquification of the corneaCorneaThe cornea is the transparent front part of the eye that covers the iris, pupil, and anterior chamber. Together with the lens, the cornea refracts light, with the cornea accounting for approximately two-thirds of the eye's total optical power. In humans, the refractive power of the cornea is...
. - Exposure to concentrations of 15 ppm cannot be tolerated for more than 1 minute, and exposure to 4 ppm for a few seconds is temporarily disabling.
- Exposure to 0.3-0.37 ppm chloropicrin for 3 to 30 seconds causes tearing and eye pain. Exposure to 15 ppm for a few seconds can cause respiratory tract injury.
- Exposure to 119 ppm in air for 30 minutes is lethal; death is caused by pulmonary oedema.
Examples of industrial exposure in humans: 27 workers in a cellulose factory who were exposed to high levels of chloropicrin for 3 minutes developed pneumonitis
Pneumonitis
Pneumonitis or pulmonitis is a general term that refers to inflammation of lung tissue.Pneumonia is pneumonitis combined with consolidation and exudation...
after 3 to 12 hours of irritated coughing and difficulty on breathing; they subsequently developed pulmonary oedema, and one died.
EU classification of chloropicrin is:
R22 Harmful if swallowed, R26 Very toxic by inhalation, R36/37/38 Irritating to eyes, skin and respiratory system, R43 May cause sensitisation by skin contact, R50/53 Very toxic to aquatic organisms, may cause long term adverse effects in the aquatic environment.
Because of chloropicrin's stability, protection requires highly effective absorbents, such as activated charcoal. Chloropicrin, unlike its relative compound phosgene
Phosgene
Phosgene is the chemical compound with the formula COCl2. This colorless gas gained infamy as a chemical weapon during World War I. It is also a valued industrial reagent and building block in synthesis of pharmaceuticals and other organic compounds. In low concentrations, its odor resembles...
, is absorbed readily at any temperature, which may pose a threat in low or high temperature climates.
The use of the substance has been restricted by the U.S. government
Federal government of the United States
The federal government of the United States is the national government of the constitutional republic of fifty states that is the United States of America. The federal government comprises three distinct branches of government: a legislative, an executive and a judiciary. These branches and...
, although such restriction is outdated now
Portrayal in Media
In the 1987 Movie DragnetDragnet (1987 film)
Dragnet is a 1987 film comedy starring Dan Aykroyd and Tom Hanks, directed by Tom Mankiewicz, based on the television crime drama of the same name starring Jack Webb. The screenplay is written by Aykroyd, Alan Zweibel and Mankiewicz. The original music score is by Ira Newborn...
, detectives Joe Friday (Dan Aykroyd
Dan Aykroyd
Daniel Edward "Dan" Aykroyd, CM is a Canadian comedian, actor, screenwriter, musician, winemaker and ufologist. He was an original cast member of Saturday Night Live, an originator of The Blues Brothers and Ghostbusters and has had a long career as a film actor and screenwriter.-Early...
) and Pep Streebeck (Tom Hanks
Tom Hanks
Thomas Jeffrey "Tom" Hanks is an American actor, producer, writer, and director. Hanks worked in television and family-friendly comedies, gaining wide notice in 1988's Big, before achieving success as a dramatic actor in several notable roles, including Andrew Beckett in Philadelphia, the title...
) thwart an attempt by mad cultists to release a tanker truck of trichloronitromethane at a party attended by several prominent Los Angeles city officials.
The effects cited in explaining the substance (vomiting, suffocation, and death) are consistent with the actual chemical.