Calomel

Last updated
Calomel
Calomel, Terlinguaite-222734.jpg
Amber calomel crystals and bright yellow terlinguaite on gossan matrix, 3 mm. across
General
Category Halide mineral
Formula
(repeating unit)
(Hg2)2+Cl2
IMA symbol Clo [1]
Strunz classification 3.AA.30
Crystal system Tetragonal
Crystal class Ditetragonal dipyramidal 4/mmm (4/m 2/m 2/m) -
Unit cell a = 4.4795(5) Å, c = 10.9054(9) Å; Z=4
Identification
ColorColorless, white, grayish, yellowish white, yellowish grey to ash-grey, brown
Crystal habit Crystals commonly tabular to prismatic, equant pyramidal; common as drusy crusts, earthy, massive.
Twinning Contact and penetration twins on {112}
Cleavage Good on {110}, uneven to imperfect on {011}
Fracture Conchoidal
Tenacity Sectile
Mohs scale hardness1.5
Luster Adamantine
Diaphaneity Transparent to translucent
Specific gravity 7.5
Optical propertiesUniaxial (+); very high relief
Refractive index nω = 1.973 nε = 2.656
Birefringence δ = 0.683
Pleochroism Weak, E > O
Ultraviolet fluorescence Brick-red under UV
References [2] [3] [4]

Calomel is a mercury chloride mineral with formula Hg2Cl2 (see mercury(I) chloride). It was used as a medicine from the 16th to early 20th century, despite frequently causing mercury poisoning in patients. [5]

Contents

The name derives from Greek kalos (beautiful) and melas (black) because it turns black on reaction with ammonia. This was known to alchemists. [3]

Calomel occurs as a secondary mineral which forms as an alteration product in mercury deposits. It occurs with native mercury, amalgam, cinnabar, mercurian tetrahedrite, eglestonite, terlinguaite, montroydite, kleinite, moschelite, kadyrelite, kuzminite, chursinite, kelyanite, calcite, limonite and various clay minerals. [2]

The type locality is Moschellandsburg, Alsenz-Obermoschel, Rhineland-Palatinate, Germany. [3]

History

The substance later known as calomel was first documented in ancient Persia by medical historian Rhazes in year 850. Only a few of the compounds he mentioned could be positively identified as calomel, as not every alchemist disclosed what compounds they used in their drugs. [6] Calomel first entered Western medical literature in 1608, when Oswald Croll wrote about its preparation in his Tyroncium Chemicum. It was not called calomel until 1655, when the name was created by Théodore de Mayerne, [7] who had published its preparation and formula in “Pharmacopoeia Londinensis" in 1618. [6]

Calomel was a common medicine from the 16th to 20th century, despite causing mercury poisoning. Antique medicine bottle marked calomel.jpg
Calomel was a common medicine from the 16th to 20th century, despite causing mercury poisoning.

By the 19th century, calomel was viewed as a panacea, or miracle drug, and was used against almost every disease, including syphilis, bronchitis, cholera, ingrown toenails, teething, gout, tuberculosis, influenza, and cancer. During the 18th and early 19th centuries pharmacists used it sparingly; but by the late 1840s, it was being prescribed in heroic doses [8] —due in part to the research of Benjamin Rush, who coined the term "heroic dose" to mean about 20 grains (1.3 g) taken four times daily. [9] This stance was supported by Dr. Samuel Cartwright, who believed that large doses were "gentlest" on the body. [10] As calomel rose in popularity, more research was done into how it worked.

J. Annesley was one of the first to write about the differering effects of calomel when taken in small or large doses. [10] Through experimentation on dogs, Annesley concluded that calomel acted more like a laxative on the whole body rather than acting specifically on the vascular system or liver as previous physicians believed. [10] In 1853, Samuel Jackson described the harmful effects of calomel on children in his publication for Transactions of Physicians of Philadelphia. [8] He noted that calomel had harmful effects causing gangrene on the skin, loss of teeth, and deterioration of the gums. [8] On May 4, 1863, William A. Hammond, the United States’ Surgeon-General, stated that calomel would no longer be used in the army as it was being abused by soldiers and physicians alike. [8] This caused much debate in the medical field, and eventually led to his removal as Surgeon-General. [11] Calomel continued to be used well into the 1890s and even into the early 20th century. [8] Eventually calomel’s popularity began to wane as more research was done, and scientists discovered that the mercury in the compound was poisoning patients.

Calomel was the main of the three components of the pill number 9 of the British army during the First World War. [12]

Electrochemistry

Calomel is used as the interface between metallic mercury and a chloride solution in a saturated calomel electrode, which is used in electrochemistry to measure pH and electrical potentials in solutions. In most electrochemical measurements, it is necessary to keep one of the electrodes in an electrochemical cell at a constant potential. This so-called reference electrode allows control of the potential of a working electrode. [13]

Chemical properties

Packets of calomel. Packet of mercurous chloride tablets, Kassel, Germany, 1914- Wellcome L0058828.jpg
Packets of calomel.

Calomel is a powder that is white when pure, and it has been used as a pigment in painting in 17th century South Americas art and in European medieval manuscripts. [14] When it is exposed to light or contains impurities it takes on a darker tint. [7] Calomel is made up of mercury and chlorine with the chemical formula Hg2Cl2. Depending on how calomel was administered, it affected the body in different ways. Taken orally, calomel damaged mainly the lining of the gastrointestinal tract. Mercury salts (such as calomel) are insoluble in water and therefore do not absorb well through the wall of the small intestine. Some of the calomel in the digestive system will likely be oxidized into a form of mercury that can be absorbed through the intestine, but most of it will not. [15] Oral calomel was actually the safest form of the drug to take, especially in low doses. Most of the calomel ingested will be excreted through urine and stool. [15]

Powdered forms of calomel were much more toxic, as their vapors damaged the brain. Once inhaled, the calomel enters the bloodstream and the mercury binds with the amino acids methionine, cysteine, homocysteine and taurine. [15] This is because of the sulfur group these amino acids contain, which mercury has a high affinity for. It is able to pass through the blood brain barrier and builds up in the brain. Mercury also has the ability to pass through the placenta, causing damage to unborn babies if a pregnant mother is taking calomel. [15]

Calomel was manufactured in two ways - sublimation and precipitation. When calomel first started being manufactured it was done through sublimation. Calomel made through sublimation tends to be a very fine white powder. [7] There was some controversy over the sublimation of calomel. Many argued that the more times calomel was sublimed, the purer it got. Opponents believed that the repeated sublimation made calomel lose some of its therapeutic ability. [6] In 1788 chemist Carl Wilhelm Scheele came up with the mechanism to make precipitated calomel. This became rapidly popular in the pharmaceutical industry because it was both a cheaper and safer form of production. [6] Precipitation also tended to form very pure calomel salts. [7]

Medicine

An advertisement from 1896 for a medicine containing calomel. Pharmaceutical advert for "Tabloids" Livingstone Rousers. Wellcome L0074492.jpg
An advertisement from 1896 for a medicine containing calomel.

Calomel was a popular medicine used during the Victorian period, and was widely used as a treatment for a variety of ailments during the American Civil War. The medication was available in two forms, blue pills and blue masses. [11] The blue pill was an oral form of calomel containing mercury that was often mixed with a sweet substance, like licorice or sugar in order to be taken by mouth. The blue mass was a solid form of calomel in which a piece could be pinched off and administered[ how? ] by a physician or other medical provider. Neither form of the medication came with a standardization of dosing. There was no way of knowing how much mercurous chloride each dose contained. [11]

Uses

Calomel was marketed as a purgative agent to relieve congestion and constipation; however, physicians at the time had no idea what the medication’s mechanism of action was. They learned how calomel worked through trial and error. It was observed that small doses of calomel acted as a stimulant, often leading to bowel movements, while larger doses caused sedation. [8] During the 19th century, calomel was used to treat numerous illnesses and diseases like mumps, typhoid fever, and others—especially those that impact the gastrointestinal tract, such as constipation, dysentery, and vomiting. [9] As mercury softened the gums, calomel was the principal constituent of teething powders until the mid-twentieth century. [16] Babies given calomel for teething often suffered from acrodynia. [17]

Side effects

Label from a calomel and cinnabar specimen Calomel-bem-10c.jpg
Label from a calomel and cinnabar specimen

It became popular in the late 18th century to give calomel in extremely high doses, as Benjamin Rush normalized the heroic dose. This caused many patients to experience many painful and sometimes life-threatening side effects.

Calomel, in high doses, led to mercury poisoning, which had the potential to cause permanent deformities and even death. Some patients experienced gangrene of the mouth generated by the mercury in the medicine, which caused the tissue on the cheeks and gums inside the mouth to break down and die. Some patients would lose teeth, while others were left with facial deformities. [11]

High doses of calomel would often lead to extreme cramping, vomiting, and bloody diarrhea; however, at the time, this was taken as a sign that the calomel was working to purge the system and rid the disease. [9] Calomel was often administered as a treatment for dysentery; the effects of calomel would often worsen the severe diarrhea associated with dysentery and acted as a catalyst in speeding up the effects of dehydration. [11]

One victim was Alvin Smith, the eldest brother of Joseph Smith, founder of the Church of Jesus Christ of Latter-day Saints. [18] Alvin was suffering from a "bilious colic" better known as abdominal pain.

It was also used by Charles Darwin to treat his mysterious chronic gastrointestinal illness, which has recently been attributed to Crohn's disease. [19]

Eventually, it was determined that calomel was causing more harm than good, as the side effects were often worse than the illness it was being used to treat; because of this, calomel was removed from medical supply shelves. [9]

Citations

  1. Warr, L.N. (2021). "IMA–CNMNC approved mineral symbols". Mineralogical Magazine. 85 (3): 291–320. Bibcode:2021MinM...85..291W. doi: 10.1180/mgm.2021.43 . S2CID   235729616.
  2. 1 2 The Handbook of Mineralogy
  3. 1 2 3 Calomel on Mindat
  4. Calomel on Webmin
  5. Davis, L. E (2000-07-01). "Unregulated potions still cause mercury poisoning". Western Journal of Medicine. 173 (1): 19. doi:10.1136/ewjm.173.1.19. PMC   1070962 . PMID   10903282.
  6. 1 2 3 4 Urdang, George (1948). "The Early Chemical and Pharmaceutical History of Calomel". Chymia. 1: 93–108. doi:10.2307/27757117. JSTOR   27757117.
  7. 1 2 3 4 Means, Alexander (1845). "Calomel—Its Chemical Characteristics and Mineral Origins Considered". Southern Medical and Surgical Journal: 98.
  8. 1 2 3 4 5 6 Haller, Jr., John S. (1971). "Samson of the Materia: Medical Theory and the Use and Abuse of Calomel: In Nineteenth Century America Part II". Pharmacy in History. 13 (2): 67–76. JSTOR   41108706.
  9. 1 2 3 4 Risse, Guenter B. (1973). "Calomel and the American Medical Sects during the Nineteenth Century". Mayo Clinic Proceedings (XLVIII): 57–64.
  10. 1 2 3 Haller, Jr, John S. (1971). "Samson of the Materia Medica: Medical Theory and the Use and Abuse of Calomel: In Nineteenth Century America Part I". Pharmacy in History. 13 (1): 27–34. JSTOR   41108691.
  11. 1 2 3 4 5 Schroeder-Lein, Glenna (2008). The Encyclopedia of Civil War Medicine. Routledge. pp. 10–58.{{cite book}}: CS1 maint: location missing publisher (link)
  12. "Qué era la píldora número 9, la pastilla "curalotodo" que recibían los soldados aliados durante la I Guerra Mundial". BBC News Mundo (in Spanish). Retrieved 2023-11-09.
  13. Kahlert, Heike (2010-09-01), "Reference Electrodes", Electroanalytical Methods, Springer-Verlag Berlin Heidelberg, pp.  291–308, doi:10.1007/978-3-642-02915-8_15, ISBN   978-3-642-02914-1 , retrieved 2018-07-10. PDF available.
  14. Crippa, Mila; Legnaioli, Stefano; Kimbriel, Christine; Ricciardi, Paola (2021). "New evidence for the intentional use of calomel as a white pigment". Journal of Raman Spectroscopy. 52 (1): 15–22. Bibcode:2021JRSp...52...15C. doi:10.1002/jrs.5876. ISSN   0377-0486.
  15. 1 2 3 4 Bernhoft, Robin (December 2011). "Mercury Toxicity and Treatment: A Review of the Literature". Journal of Environmental and Public Health. 2012: 460508. doi: 10.1155/2012/460508 . PMC   3253456 . PMID   22235210.
  16. Swiderski, Richard M. (2009). Calomel in America : mercurial panacea, war, song and ghosts. Boca Raton, FA: BrownWalker Press. pp. 37–9. ISBN   978-1-59942-467-5.
  17. Kang, Lydia; Pedersen, Nate (2017). "Chapter 1: Mercury". Quackery: A Brief History of the Worst Ways to Cure Everything. New York: Workman Publishing.
  18. Schmid, Jennifer. "Beautiful Black Poison". Weston A. Price Foundation . Retrieved 2017-10-05.
  19. Orrego, Fernando (2007). "Darwin's illness: a final diagnosis". Notes and Records of the Royal Society of London. 61 (1). The Royal Society Publishing: 23–9. doi:10.1098/rsnr.2006.0160. PMID   17575947. S2CID   5804417.

General bibliography

Related Research Articles

<span class="mw-page-title-main">Aspirin</span> Medication

Aspirin, also known as acetylsalicylic acid (ASA), is a nonsteroidal anti-inflammatory drug (NSAID) used to reduce pain, fever, and/or inflammation, and as an antithrombotic. Specific inflammatory conditions which aspirin is used to treat include Kawasaki disease, pericarditis, and rheumatic fever.

<span class="mw-page-title-main">Poison</span> Substance that causes death, injury or harm to organs

A poison is any chemical substance that is harmful or lethal to living organisms. The term is used in a wide range of scientific fields and industries, where it is often specifically defined. It may also be applied colloquially or figuratively, with a broad sense.

<span class="mw-page-title-main">Laxative</span> Agents that relax and loosen the bowels and stools

Laxatives, purgatives, or aperients are substances that loosen stools and increase bowel movements. They are used to treat and prevent constipation.

<span class="mw-page-title-main">Salammoniac</span> Halide mineral

Salammoniac, also sal ammoniac or salmiac, is a rare naturally occurring mineral composed of ammonium chloride, NH4Cl. It forms colorless, white, or yellow-brown crystals in the isometric-hexoctahedral class. It has very poor cleavage and is brittle to conchoidal fracture. It is quite soft, with a Mohs hardness of 1.5 to 2, and it has a low specific gravity of 1.5. It is water-soluble. Salammoniac is also the archaic name for the chemical compound ammonium chloride.

<span class="mw-page-title-main">Route of administration</span> Path by which a drug, fluid, poison, or other substance is taken into the body

In pharmacology and toxicology, a route of administration is the way by which a drug, fluid, poison, or other substance is taken into the body.

<span class="mw-page-title-main">Mercury poisoning</span> Poisoning caused by mercury chemicals

Mercury poisoning is a type of metal poisoning due to exposure to mercury. Symptoms depend upon the type, dose, method, and duration of exposure. They may include muscle weakness, poor coordination, numbness in the hands and feet, skin rashes, anxiety, memory problems, trouble speaking, trouble hearing, or trouble seeing. High-level exposure to methylmercury is known as Minamata disease. Methylmercury exposure in children may result in acrodynia in which the skin becomes pink and peels. Long-term complications may include kidney problems and decreased intelligence. The effects of long-term low-dose exposure to methylmercury are unclear.

<span class="mw-page-title-main">Heroic medicine</span> Outdated model of medicine

Heroic medicine, also referred to as heroic depletion theory, was a therapeutic method advocating for rigorous treatment of bloodletting, purging, and sweating to shock the body back to health after an illness caused by a humoral imbalance. Rising to the front of orthodox medical practice in the "Age of Heroic Medicine" (1780–1850), it fell out of favor in the mid-19th century as gentler treatments were shown to be more effective and the idea of palliative treatment began to develop.

<span class="mw-page-title-main">Mercury(II) chloride</span> Chemical compound known as corrosive sublimate

Mercury(II) chloride (or mercury bichloride, mercury dichloride), historically also known as sulema or corrosive sublimate, is the inorganic chemical compound of mercury and chlorine with the formula HgCl2, used as a laboratory reagent. It is a white crystalline solid and a molecular compound that is very toxic to humans. Once used as a treatment for syphilis, it is no longer used for medicinal purposes because of mercury toxicity and the availability of superior treatments.

<span class="mw-page-title-main">Mercurial diuretic</span>

Mercurial diuretics are a form of renal diuretic containing mercury.

<span class="mw-page-title-main">Realgar</span> Arsenic sulfide mineral

Realgar, also known as ″arsenic blende″, ″ruby sulphur″ or ″ruby of arsenic″, is an arsenic sulfide mineral with the chemical formula α-As4S4. It is a soft, sectile mineral occurring in monoclinic crystals, or in granular, compact, or powdery form, often in association with the related mineral, orpiment. It is orange-red in color, melts at 320 °C, and burns with a bluish flame releasing fumes of arsenic and sulfur. Realgar is soft with a Mohs hardness of 1.5 to 2 and has a specific gravity of 3.5. Its streak is orange colored. It is trimorphous with pararealgar and bonazziite.

<span class="mw-page-title-main">Teething</span> Infants gaining their first teeth

Teething is the process by which an infant's first teeth appear by emerging through the gums, typically arriving in pairs. The mandibular central incisors are the first primary teeth to erupt, usually between 6 and 10 months of age and usually causes discomfort and pain to the infant. It can take several years for all 20 teeth to complete the tooth eruption. Though the process of teething is sometimes referred to as "cutting teeth", when teeth emerge through the gums they do not cut through the flesh. Instead, hormones are released within the body that cause some cells in the gums to die and separate, allowing the teeth to come through.

<span class="mw-page-title-main">Sodium fluoride</span> Ionic compound (NaF)

Sodium fluoride (NaF) is an inorganic compound with the formula NaF. It is a colorless or white solid that is readily soluble in water. It is used in trace amounts in the fluoridation of drinking water to prevent tooth decay, and in toothpastes and topical pharmaceuticals for the same purpose. In 2021, it was the 291st most commonly prescribed medication in the United States, with more than 600,000 prescriptions. It is also used in metallurgy and in medical imaging.

<span class="mw-page-title-main">Mercury(I) chloride</span> Chemical compound

Mercury(I) chloride is the chemical compound with the formula Hg2Cl2. Also known as the mineral calomel (a rare mineral) or mercurous chloride, this dense white or yellowish-white, odorless solid is the principal example of a mercury(I) compound. It is a component of reference electrodes in electrochemistry.

<span class="mw-page-title-main">Colestyramine</span> Pharmaceutical drug

Colestyramine (INN) or cholestyramine (USAN) is a bile acid sequestrant, which binds bile in the gastrointestinal tract to prevent its reabsorption. It is a strong ion exchange resin, which means it can exchange its chloride anions with anionic bile acids in the gastrointestinal tract and bind them strongly in the resin matrix. The functional group of the anion exchange resin is a quaternary ammonium group attached to an inert styrene-divinylbenzene copolymer.

Nathaniel Peabody was an American physician and dentist from Boston and Salem, Massachusetts, having studied at Dartmouth College in the class of 1800. Peabody was described as an "experimentally minded doctor and dentist". He began his medical practice using "heroic" practices of large amounts of emetic and purgative medicines. For instance, a patient could become very sick or die from mercury poisoning of a purgative called calomel. Upon becoming familiar with the work of Dr. Samuel Hahnemann, Peabody used botanical medicines in small doses to treat his patients, which reduced the side effects and potential death from the heroic practices.

The saturated calomel electrode (SCE) is a reference electrode based on the reaction between elemental mercury and mercury(I) chloride. It has been widely replaced by the silver chloride electrode, however the calomel electrode has a reputation of being more robust. The aqueous phase in contact with the mercury and the mercury(I) chloride (Hg2Cl2, "calomel") is a saturated solution of potassium chloride in water. The electrode is normally linked via a porous frit (sometimes coupled to a salt bridge) to the solution in which the other electrode is immersed.

Acrodynia is a medical condition which occurs due to mercury poisoning. The condition of pain and dusky pink discoloration in the hands and feet is due to exposure or ingesting of mercury. It was known as Pink Disease before it was accepted that it was just mercury poisoning. The word acrodynia is derived from the Greek: ακρος, which means end or extremity, and Greek: οδυνη, which means pain. As such, it might be (erroneously) used to indicate that a patient has pain in the hands or feet. The condition is known by various other names including hydrargyria, mercurialism, erythredema, erythredema polyneuropathy, Bilderbeck's, Selter's, Swift's and Swift-Feer disease.

Blue mass was the name of a mercury-based medicine common from the 17th to the 19th centuries. The oldest formula is ascribed to one Barbarossa, in a letter to Francis I of France.

<span class="mw-page-title-main">Mercury (element)</span> Chemical element, symbol Hg and atomic number 80

Mercury is a chemical element; it has symbol Hg and atomic number 80. It is also known as quicksilver and was formerly named hydrargyrum from the Greek words hydor (water) and argyros (silver). A heavy, silvery d-block element, mercury is the only metallic element that is known to be liquid at standard temperature and pressure; the only other element that is liquid under these conditions is the halogen bromine, though metals such as caesium, gallium, and rubidium melt just above room temperature.

<span class="mw-page-title-main">Salicylate poisoning</span> Medical condition

Salicylate poisoning, also known as aspirin poisoning, is the acute or chronic poisoning with a salicylate such as aspirin. The classic symptoms are ringing in the ears, nausea, abdominal pain, and a fast breathing rate. Early on, these may be subtle, while larger doses may result in fever. Complications can include swelling of the brain or lungs, seizures, low blood sugar, or cardiac arrest.