Pulmonary agent

Last updated

A pulmonary agent, or choking agent, is a chemical weapon agent designed to impede a victim's ability to breathe. They operate by causing a build-up of fluids in the lungs, which then leads to suffocation. Exposure to the eyes and skin tends to be corrosive, causing blurred vision and severe deep burns. Inhalation of these agents cause burning of the throat, coughing, vomiting, headache, pain in chest, tightness in chest, and respiratory and circulatory failure.

Respiratory system A biological system of specific organs and structures for gas exchange in animals and plants

The respiratory system is a biological system consisting of specific organs and structures used for gas exchange in animals and plants. The anatomy and physiology that make this happen varies greatly, depending on the size of the organism, the environment in which it lives and its evolutionary history. In land animals the respiratory surface is internalized as linings of the lungs. Gas exchange in the lungs occurs in millions of small air sacs called alveoli in mammals and reptiles, but atria in birds. These microscopic air sacs have a very rich blood supply, thus bringing the air into close contact with the blood. These air sacs communicate with the external environment via a system of airways, or hollow tubes, of which the largest is the trachea, which branches in the middle of the chest into the two main bronchi. These enter the lungs where they branch into progressively narrower secondary and tertiary bronchi that branch into numerous smaller tubes, the bronchioles. In birds the bronchioles are termed parabronchi. It is the bronchioles, or parabronchi that generally open into the microscopic alveoli in mammals and atria in birds. Air has to be pumped from the environment into the alveoli or atria by the process of breathing which involves the muscles of respiration.

Asphyxia Condition of severely deficient supply of oxygen to the body caused by abnormal breathing

Asphyxia or asphyxiation is a condition of deficient supply of oxygen to the body that arises from abnormal breathing. An example of asphyxia is choking. Asphyxia causes generalized hypoxia, which affects primarily the tissues and organs. There are many circumstances that can induce asphyxia, all of which are characterized by an inability of an individual to acquire sufficient oxygen through breathing for an extended period of time. Asphyxia can cause coma or death.

Examples of pulmonary agents include:

Chlorine Chemical element with atomic number 17

Chlorine is a chemical element with symbol Cl and atomic number 17. The second-lightest of the halogens, it appears between fluorine and bromine in the periodic table and its properties are mostly intermediate between them. Chlorine is a yellow-green gas at room temperature. It is an extremely reactive element and a strong oxidising agent: among the elements, it has the highest electron affinity and the third-highest electronegativity on the Pauling scale, behind only oxygen and fluorine.

Chloropicrin, also known as PS and nitrochloroform, is a chemical compound currently used as a broad-spectrum antimicrobial, fungicide, herbicide, insecticide, and nematicide. Its chemical structural formula is Cl3CNO2.

Diphosgene chemical compound

Diphosgene is a chemical compound with the formula ClCO2CCl3. This colorless liquid is a valuable reagent in the synthesis of organic compounds. Diphosgene is related to phosgene and has comparable toxicity, but is more conveniently handled because it is a liquid, whereas phosgene is a gas.

Phosgene is the most dangerous commonly used pulmonary agent (although disulfur decafluoride and perfluoroisobutene are both even more dangerous, with respectively 4 and 10 times the lethality of phosgene, neither is widely used). It is a colorless gas under ordinary conditions. It has a vapor density 3.4 times greater than that of air, allowing it to remain low in the air for long periods of times. Phosgene leads to massive pulmonary edema, which reaches maximum symptoms in 12 hours after exposure, followed by death within 24 to 48 hours.

Phosgene is the chemical compound with the formula COCl2. A colorless gas, in low concentrations its odor resembles freshly cut hay or grass. Phosgene is a valued industrial building block, especially for the production of urethanes and polycarbonate plastics. However, it is very poisonous and was used as a chemical weapon during World War I where it was responsible for 85,000 deaths. In addition to its industrial production, small amounts occur from the breakdown and the combustion of organochlorine compounds.

Chlorine is an element used in industry. It is one of the most commonly manufactured chemicals in the United States. It is used to make pesticides, rubber, and solvents. It is also used in drinking water and swimming pools to kill bacteria. The extent of poisoning chlorine causes depends on the amount of chlorine to which a person is exposed.

History

The first major use of these agents came on April 22, 1915, at the Second Battle of Ypres in Belgium. The Germans opened up 168 tons of chlorine gas on the French, Canadian and British troops which created a wind-borne cloud of chemical gas that opened up a breach in the lines. However, the Germans were not prepared to exploit the opening. In 1917 the Germans also introduced the agent phosgene. By then both sides had mastered the techniques of new choking agents such as diphosgene, chloropicrin, and perfluoroisobutene which allowed numerous attacks to be made. By the end of World War I, phosgene was responsible for roughly 80% of all deaths related to chemical attacks.[ citation needed ]

Second Battle of Ypres A battle in 1915 during the First World War

During World War I, the Battle of Ypres 1915 was fought from 22 April – 25 May 1915 for control of the strategic Flemish town of Ypres in western Belgium. The First Battle of Ypres had been fought the previous autumn. The Second Battle of Ypres was the first mass use by Germany of poison gas on the Western Front. It also marked the first time a former colonial force defeated a European power in Europe.

Related Research Articles

Sulfur mustard chemical compound

Sulfur mustard, commonly known as mustard gas, is the prototypical substance of the sulfur-based family of cytotoxic and vesicant chemical warfare agents known as the sulfur mustards, which can form large blisters on exposed skin and in the lungs. They have a long history of use as a blister-agent in warfare and, along with organoarsenic compounds, are the most well-studied of such agents. Related chemical compounds with similar chemical structure and similar properties form a class of compounds known collectively as sulfur mustards or mustard agents. Pure sulfur mustards are colorless, viscous liquids at room temperature. When used in impure form, such as warfare agents, they are usually yellow-brown and have an odor resembling mustard plants, garlic, or horseradish, hence the name. The common name of "mustard gas" is considered inaccurate because the sulfur mustard is not actually vaporized, but dispersed as a fine mist of liquid droplets. Sulfur mustard was originally assigned the name LOST, after the scientists Wilhelm Lommel and Wilhelm Steinkopf, who developed a method of large-scale production for the Imperial German Army in 1916.

Chemical warfare type of warfare that involves using the toxic properties of chemical substances as weapons

Chemical warfare (CW) 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, all of which are considered "weapons of mass destruction" (WMDs). None of these fall under the term conventional weapons which are primarily effective due to their destructive potential. In theory, with proper protective equipment, training, and decontamination measures, the primary effects of chemical weapons can be overcome. In practice, they continue to cause much suffering, as most victims are defenceless civilians. Many nations possess vast stockpiles of weaponized agents in preparation for wartime use. The threat and the perceived threat have become strategic tools in planning both measures and counter-measures.

Chemical weapons in World War I First large-scale use of chemical weapons leading to their banning

The use of toxic chemicals as weapons dates back thousands of years, but the first large scale use of chemical weapons was during World War I. They were primarily used to demoralize, injure, and kill entrenched defenders, against whom the indiscriminate and generally very slow-moving or static nature of gas clouds would be most effective. The types of weapons employed ranged from disabling chemicals, such as tear gas, to lethal agents like phosgene, chlorine, and mustard gas. This chemical warfare was a major component of the first global war and first total war of the 20th century. The killing capacity of gas was limited, with about ninety thousand fatalities from a total of 1.3 million casualties caused by gas attacks. Gas was unlike most other weapons of the period because it was possible to develop countermeasures, such as gas masks. In the later stages of the war, as the use of gas increased, its overall effectiveness diminished. The widespread use of these agents of chemical warfare, and wartime advances in the composition of high explosives, gave rise to an occasionally expressed view of World War I as "the chemist's war" and also the era where weapons of mass destruction were created.

United Kingdom and weapons of mass destruction

The United Kingdom possesses, or has possessed, a variety of weapons of mass destruction, including nuclear, biological, and chemical weapons. The United Kingdom is one of the five official nuclear weapon states under the Treaty on the Non-Proliferation of Nuclear Weapons and has an independent nuclear deterrent. The UK has been estimated to have a stockpile of 120 active nuclear warheads and 215 nuclear warheads in total. It had renounced the use of chemical and biological weapons in 1956 and subsequently destroyed its general stocks.

Chemical pneumonitis is inflammation of the lung caused by aspirating or inhaling irritants. It is sometimes called a "chemical pneumonia", though it is not infectious. There are two general types of chemical pneumonitis: acute and chronic.

Phosgene oxime, or CX, is an organic compound with the formula Cl2CNOH. It is a potent chemical weapon, specifically a nettle agent. The compound itself is a colorless solid, but impure samples are often yellowish liquids. It has a strong, disagreeable odor and a violently irritating vapor.

Chemical, biological (CB) — and sometimes radiological — warfare agents were assigned what is termed a military symbol by the U.S. military until the American chemical and biological weapons programs were terminated. Military symbols applied to the CB agent fill, and not to the entire weapon. A chemical or biological weapon designation would be, for example, "Aero-14/B", which could be filled with GB, VX, TGB, or with a biological modification kit – OU, NU, UL, etc. A CB weapon is an integrated device of (1) agent, (2) dissemination means, and (3) delivery system.

The Edgewood Chemical Activity was a U.S. Army site located in Edgewood, Maryland that stored chemical weapons. Its construction was started by Ordnance Corps in November 1917 and completed in less than a year. The arsenal was to employ about 10,000 civilian and military personnel in fabrication of chemical weapons and filling gas shells with phosgene, chlorpicrin, chlorine and mustard gas. Since 1941, the U.S. Army stored approximately five percent of the nation's original chemical agent in steel ton containers, at the Edgewood Area of Aberdeen Proving Ground.

Disulfur decafluoride chemical compound

Disulfur decafluoride (S2F10) is a chemical compound discovered in 1934 by Denbigh and Whytlaw-Gray. Each sulfur atom of the S2F10 molecule is octahedral, and surrounded by five fluorine atoms. S2F10 is highly toxic, with toxicity four times that of phosgene. It was considered a potential chemical warfare pulmonary agent in World War II because it does not produce lacrimation or skin irritation, thus providing little warning of exposure. It is produced by the electrical decomposition of sulfur hexafluoride (SF6)—an essentially inert insulator used in high voltage systems such as transmission lines, substations and switchgear. S2F10 is also made during the production of SF6, but is distilled out. It is a colorless liquid with a burnt match smell similar to sulfur dioxide.

Perfluoroisobutene (PFIB), also known as 1,1,3,3,3-pentafluoro-2-(trifluoromethyl)prop-1-ene, is a fluorocarbon alkene. It is a hydrophobic reactive gas with boiling point at 7 °C. It is a strong electrophile.

Green Cross (Grünkreuz) is a World War I chemical warfare pulmonary agent consisting of chloropicrin, phosgene and/or trichloromethyl chloroformate.

Chemical weapons were widely used by the United Kingdom in World War I, and while the use of chemical weapons was suggested by Churchill and others postwar in Mesopotamia and in World War II, it appears that they were not actually used, although some historians disagree. While the UK was a signatory of the Hague Conventions of 1899 and 1907 which outlawed the use of poison gas shells, the conventions omitted mention of deployment from cylinders, probably because that had not been considered.

Acute inhalation injury may result from frequent and widespread use of household cleaning agents and industrial gases. The airways and lungs receive continuous first-pass exposure to non-toxic and irritant or toxic gases via inhalation. Irritant gases are those that, on inhalation, dissolve in the water of the respiratory tract mucosa and provoke an inflammatory response, usually from the release of acidic or alkaline radicals. Smoke, chlorine, phosgene, sulfur dioxide, hydrogen chloride, hydrogen sulfide, nitrogen dioxide, ozone, and ammonia are common irritants.

There are allegations that chemical weapons were used by the Sri Lankan military and the rebel Liberation Tigers of Tamil Eelam (LTTE) during the Sri Lankan Civil War. No strong evidence for indicating the consistent use of such weapons during the war have been found thus far.

1915 German phosgene attack

The German phosgene attack of 19 December 1915 was the first use of phosgene gas against British troops by the German army. The gas attack took place at Wieltje, north-east of Ypres in Belgian Flanders on the Western Front in the First World War. German gas attacks on Allied troops had begun on 22 April 1915, during the Second Battle of Ypres using chlorine against French and Canadian units. The surprise led to the capture of much of the Ypres Salient, after which the effectiveness of gas as a weapon diminished, because the French and British introduced anti-gas measures and protective helmets. The German Nernst-Duisberg-Commission investigated the feasibility of adding the much more lethal phosgene to chlorine. Mixed chlorine and phosgene gas was used at the end of May 1915, in attacks on the Western Front against French troops and on Russian troops on the Eastern Front.

Chlorine gas poisoning is an illness resulting from the effects of exposure to chlorine beyond the threshold limit value.

References

This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.