Carbon tetrachloride

Properties

In the carbon tetrachloride molecule, four chlorine atoms are positioned symmetrically as corners in a tetrahedral configuration joined to a central carbon atom by single covalent bonds. Because of this symmetric geometry, CCl4 is non-polar. Methane gas has the same structure, making carbon tetrachloride a halomethane. As a solvent, it is well suited to dissolving other non-polar compounds such as fats and oils. It can also dissolve iodine. It is volatile, giving off vapors with an odor characteristic of other chlorinated solvents, somewhat similar to the tetrachloroethylene odor reminiscent of dry cleaners' shops.

Solid tetrachloromethane has two polymorphs: crystalline II below −47.5°C (225.6 K) and crystalline I above −47.5°C. At −47.3°C it has monoclinic crystal structure with space group C2/c and lattice constants a = 20.3, b = 11.6, c = 19.9 (.10−1 nm), β = 111°.

With a specific gravity greater than 1, carbon tetrachloride will be present as a dense nonaqueous phase liquid if sufficient quantities are spilt in the environment.

Reactions

Despite being generally inert, carbon tetrachloride can undergo various reactions. Hydrogen or an acid in the presence of an iron catalyst can reduce carbon tetrachloride to chloroform, dichloromethane, chloromethane and even methane. When its vapours are passed through a red-hot tube, carbon tetrachloride dechlorinates to tetrachloroethylene and hexachloroethane.

Carbon tetrachloride, when treated with HF, gives various compounds such as trichlorofluoromethane (R-11), dichlorodifluoromethane (R-12), chlorotrifluoromethane (R-13) and carbon tetrafluoride with HCl as the by-product: : : : : This was once one of the main uses of carbon tetrachloride, as R-11 and R-12 were widely used as refrigerants.

An alcohol solution of potassium hydroxide decomposes it to potassium chloride and potassium carbonate in water: :

Carbon is sufficiently oxophilic that many compounds react to give phosgene:

Reaction with hydrogen sulfide gives thiophosgene: :

History and synthesis

Carbon tetrachloride was originally synthesized in 1820 by Michael Faraday, who named it "protochloride of carbon", by decomposition of hexachloroethane ("perchloride of carbon") which he synthesized by chlorination of ethylene. The protochloride of carbon has been previously misidentified as tetrachloroethylene because it can be made with the same reaction of hexachloroethane. Later in the 19th century, the name "protochloride of carbon" was used for tetrachloroethylene, and carbon tetrachloride was called "bichloride of carbon" or "perchloride of carbon". Henri Victor Regnault developed another method to synthesise carbon tetrachloride from chloroform, chloroethane or methanol with excess chlorine in 1839.

Kolbe made carbon tetrachloride in 1845 by passing chlorine over carbon disulfide through a porcelain tube. Prior to the 1950s, carbon tetrachloride was manufactured by the chlorination of carbon disulfide at 105 to 130 °C:

:CS2 + 3 Cl2 → CCl4 + S2Cl2

But now it is mainly produced from methane:

:CH4 + 4 Cl2 → CCl4 + 4 HCl

The production often utilizes by-products of other chlorination reactions, such as from the syntheses of dichloromethane and chloroform. Higher chlorocarbons are also subjected to this process named "chlorinolysis":

:C2Cl6 + Cl2 → 2 CCl4

The production of carbon tetrachloride has steeply declined since the 1980s because of environmental concerns and the decreased demand for CFCs, which were derived from carbon tetrachloride. In 1992, production in the U.S./Europe/Japan was estimated at 720,000 tonnes. In the 2010s, the total amount of CCl4 produced and imported into the US annually was under 70,000 tonnes.

Natural occurrence

Carbon tetrachloride was discovered along with chloromethane and chloroform in oceans, marine algae and volcanoes. Natural emissions of carbon tetrachloride are insignificant compared to anthropogenic sources; for example, the Momotombo volcano in Nicaragua emits carbon tetrachloride at a flux of 82 grams per year while the global industrial emissions were at 2 × 1010 grams per year.

Carbon tetrachloride was found in red algae, specifically Asparagopsis taxiformis and Asparagopsis armata. It was detected in Southern Californian ecosystems, salt lakes of the Kalmykian steppe and a common liverwort in the Czech Republic.

Safety

At high temperatures in air, it decomposes or burns to produce poisonous phosgene. This was a common problem when carbon tetrachloride was used as a fire extinguisher and there have been deaths due to its conversion to phosgene reported.

Carbon tetrachloride is a suspected human carcinogen but there is no sufficient evidence of carcinogenicity in humans. The World Health Organization reports carbon tetrachloride can induce hepatocellular carcinomas (hepatomas) in mice and rats. The doses inducing hepatic tumors in mice and rats are higher than those inducing cell toxicity. The International Agency for Research on Cancer (IARC) classified this compound in Group 2B, "possibly carcinogenic to humans".

Carbon tetrachloride is one of the most potent hepatotoxins (toxic to the liver), so much so that it is widely used in scientific research to evaluate hepatoprotective agents. Exposure to high concentrations of carbon tetrachloride (including vapor) can affect the central nervous system and degenerate the liver | display-authors=etal |doi-access=free |url-access=subscription |doi-access= free

Consumption of alcohol increases the toxic effects of carbon tetrachloride and may cause more severe organ damage, such as acute renal failure, in heavy drinkers. The doses that can cause mild toxicity to non-drinkers can be fatal to drinkers.

The effects of carbon tetrachloride on human health and the environment have been assessed under REACH in 2012 in the context of the substance evaluation by France.

In 2008, a study of common cleaning products found the presence of carbon tetrachloride in "very high concentrations" (up to 101 mg/m3) as a result of manufacturers' mixing of surfactants or soap with sodium hypochlorite (bleach).

Carbon tetrachloride is also both ozone-depleting{{cite journal | name-list-style = amp | doi-access = free

Uses

Prior to being phased out due to toxicity and environmental impact, carbon tetrachloride was widely used as a dry cleaning solvent, as a refrigerant, and in lava lamps. In the last case, carbon tetrachloride is a key ingredient that adds weight to the otherwise buoyant wax.

One speciality use of carbon tetrachloride was in stamp collecting, to reveal watermarks on postage stamps without damaging them. A small amount of the liquid is placed on the back of a stamp, sitting in a black glass or obsidian tray. The letters or design of the watermark can then be seen clearly. Today, this is done on lit tables without using carbon tetrachloride.

In organic chemistry, carbon tetrachloride serves as a source of chlorine in the Appel reaction. :[[File:Appel-Reaktion M-v3.svg|left|450px|The mechanism of the Appel reaction]]

Carbon tetrachloride made from heavy chlorine-37 has been used in the detection of neutrinos and antineutrinos. Raymond Davis Jr. used carbon tetrachloride in his experiments to detect antineutrinos.

Cleaning

Being a good solvent for many materials (such as grease and tar), carbon tetrachloride was widely used as a cleaning fluid for nearly 70 years. It is nonflammable and nonexplosive and did not leave any odour on the cleaned material, unlike gasoline, which was also used for cleaning at the time. It was used as a "safe" alternative to gasoline. It was first marketed as Katharin, in the early 1890s and as Benzinoform later.

Carbon tetrachloride was recommended for regularly cleaning the type slugs of typewriters in office settings in the 1940s.

Carbon tetrachloride was the first chlorinated solvent to be used in dry-cleaning and was used until the 1950s. and methyl chloroform (trichloroethane).

Carbon tetrachloride was also used as an ingredient in dry shampoos due to its solvent properties and quick evaporation from 1903 until the 1930s, when it was discontinued due to health and safety concerns. Several women had fainted from its fumes during the hair wash at the hairdressers, and electric fans were used to blow the fumes away. In 1909, a baronet's 29-year-old daughter, Helenora Elphinstone-Dalrymple, died after having her hair shampooed with carbon tetrachloride.

It is assumed that carbon tetrachloride was still used as a dry cleaning solvent in North Korea as of 2006.

Medical uses

Anaesthetic and analgesic

Carbon tetrachloride was briefly used as a volatile inhalation anaesthetic and analgesic for intense menstruation pains and headaches in the mid-19th century. Its anaesthetic effects were known as early as 1847 or 1848.

It was introduced as a safer alternative to chloroform by the doctor Protheroe Smith in 1864. In December 1865, the Scottish obstetrician who discovered the anaesthetic effects of chloroform on humans, James Young Simpson, had experimented with carbon tetrachloride as an anaesthetic. Simpson named the compound "Chlorocarbon" for its similarity to chloroform. His experiments involved injecting carbon tetrachloride into two women's vaginas. Simpson orally consumed carbon tetrachloride and described it as having "the same effect as swallowing a capsule of chloroform".

Because of the higher amount of chlorine atoms (compared to chloroform) in its molecule, carbon tetrachloride has a stronger anaesthetic effect than chloroform and required a smaller amount. and "more pleasant than chloroform", During anaesthesia, carbon tetrachloride has caused such violent muscular contractions and negative effects on the heart in some patients that it had to be replaced with chloroform or ether.Am J Dent Sci. 1868 Jan; 1(9): 462–463. "Trial of Tetrachloride of Carbon as an Anaesthetic.—Dangerous Effects" E. Andrews https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6088960/ Such use was experimental and the anaesthetic use of carbon tetrachloride never gained popularity due to its potential toxicity.

Parasite medication

The veterinary doctor Maurice Crowther Hall (1881–1938) discovered in 1921 that carbon tetrachloride was highly effective as an anthelmintic in eradicating hookworm via ingestion. In one of the clinical trials of carbon tetrachloride, it was tested on criminals to determine its safety for use on humans. Beginning in 1922, capsules of pure carbon tetrachloride were marketed by Merck under the name Necatorina (variants include Neo-necatorina and Necatorine). Necatorina was used as a medication against parasitic diseases in humans. This medication was most prevalently used in Latin American countries. Its toxicity was not well understood at the time and toxic effects were attributed to impurities in the capsules rather than carbon tetrachloride itself. Due to carbon tetrachloride's toxicity, tetrachloroethylene (which was also investigated by Hall in 1925) replaced its use as an anthelmintic by the 1940s.

Solvent

Carbon tetrachloride once was a popular solvent in organic chemistry, but because of its adverse health effects, it is rarely used today. Its use in NMR spectroscopy has been largely superseded by deuterated solvents (mainly deuterochloroform). The use of carbon tetrachloride in the determination of oil has been replaced by various other solvents, such as tetrachloroethylene. Because it has no C–H bonds, it is a useful solvent for halogenations either by the elemental halogen or by a halogenation reagent such as N-bromosuccinimide (these conditions are known as Wohl–Ziegler bromination).

Fire suppression

Between 1902 and 1908, carbon tetrachloride-based fire extinguishers began to appear in the United States, years after Europe.

In 1910, the Pyrene Manufacturing Company of Delaware filed a patent to use carbon tetrachloride to extinguish fires. The liquid was vaporized by the heat of combustion and extinguished flames, an early form of gaseous fire suppression. At the time it was believed the gas displaced oxygen in the area near the fire, but later research found that the gas inhibited the chemical chain reaction of the combustion process.

In 1911, Pyrene patented a small, portable extinguisher that used the chemical. The extinguisher consisted of a brass bottle with an integrated hand-pump that was used to expel a jet of liquid toward the fire. As the container was unpressurized, it could easily be refilled after use.{{cite web |access-date = 23 December 2009 |url-status = dead |archive-url = https://web.archive.org/web/20100325160709/http://www.vintagefe.com/pyrene.html |archive-date = 25 March 2010 Carbon tetrachloride was suitable for liquid and electrical fires and the extinguishers were often carried on aircraft or motor vehicles. However, as early as 1920, there were reports of fatalities caused by the chemical when used to fight a fire in a confined space.

In the first half of the 20th century, another common fire extinguisher was a single-use, sealed glass globe, a "fire grenade, " filled with carbon tetrachloride or salt water. The bulb could be thrown at the base of the flames to quench the fire. The carbon tetrachloride type could also be installed in a spring-loaded wall fixture with a solder-based restraint. When the solder melted by high heat, the spring would either break the globe or launch it out of the bracket, allowing the extinguishing agent to be automatically dispersed into the fire.

Since carbon tetrachloride freezes at –23 °C, the fire extinguishers would contain only 89–90% carbon tetrachloride and 10% trichloroethylene (m.p. –85 °C) or chloroform (m.p. –63 °C) for lowering the extinguishing mixture's freezing point down to temperatures as low as –45 °C. The extinguishers with 10% trichloroethylene would contain 1% carbon disulfide as a stabiliser.

Refrigerants

Prior to the Montreal Protocol, large quantities of carbon tetrachloride were used to produce the chlorofluorocarbon refrigerants R-11 (trichlorofluoromethane) and R-12 (dichlorodifluoromethane). However, these refrigerants play a role in ozone depletion and have been phased out. Carbon tetrachloride is still used to manufacture less destructive refrigerants.

Fumigant

Carbon tetrachloride was widely used as a fumigant to kill insect pests in stored grain. It was employed in a mixture known as 80/20, that was 80% carbon tetrachloride and 20% carbon disulfide. The United States Environmental Protection Agency banned its use in 1985.

Another carbon tetrachloride fumigant preparation mixture contained acrylonitrile. Carbon tetrachloride reduced the flammability of the mixture. Most common trade names for the preparation were Acritet, Carbacryl and Acrylofume. The most common preparation, Acritet, was prepared with 34 percent acrylonitrile and 66 percent carbon tetrachloride.

Society and culture

• The French writer René Daumal intoxicated himself by inhalation of carbon tetrachloride which he used to kill the beetles he collected, to "encounter other worlds" by voluntarily plunging himself into intoxications close to comatose states.
• Carbon tetrachloride is listed (along with salicylic acid, toluene, sodium tetraborate, silica gel, methanol, potassium carbonate, ethyl acetate and "BHA") as an ingredient in Peter Parker's (Spider-Man) custom web fluid formula in the book The Wakanda Files: A Technological Exploration of the Avengers and Beyond.
• Australian YouTuber Tom of Explosions&Fire and Extractions&Ire made a video on extracting carbon tetrachloride from an old fire extinguisher in 2019, and later experimenting with it by mixing it with sodium, and the chemical gained a fan base called "Tet Gang" on social media (especially on Reddit). The channel owner later used carbon tetrachloride-themed designs in the channel's merch.
• In the Ramones song "Carbona Not Glue" released in 1977, the narrator says that huffing the vapours of Carbona, a carbon tetrachloride-based stain remover, was better than huffing glue. They later removed the song from the album as Carbona was a corporate trademark.

Famous deaths from carbon tetrachloride poisoning

• Evalyn Bostock (1917–1944), British actress who died from accidentally drinking carbon tetrachloride after mistaking it for her drink while working in a photographic darkroom.
• Harry Edwards (1887–1952), an American director who died from carbon tetrachloride poisoning shortly after directing his first television production.
• Zilphia Horton (1910–1956), American musician and activist who died from accidentally drinking a glass full of carbon tetrachloride-based typewriter cleaning fluid that she mistook for water.
• Margo Jones (1911–1955), American stage director who was exposed to the fumes of carbon tetrachloride that was used to clean off paint from a carpet. She died a week later from kidney failure.
• Jim Beck (1919–1956), American record producer, died after exposure to carbon tetrachloride fumes while cleaning recording equipment.
• Tommy Tucker (1933–1982), American blues singer, died after using carbon tetrachloride in floor refinishing.

Gallery

File:CCl4_mm.png|CCl4 measured by the Advanced Global Atmospheric Gases Experiment (AGAGE) in the lower atmosphere (troposphere) at stations around the world. Abundances are given as pollution-free monthly mean mole fractions in parts-per-trillion. File:Hats ccl4 global.png|Hemispheric and Global mean concentrations of CCl4 (NOAA/ESRL). Image:AYool CCl4 history.png|Time-series of atmospheric concentrations of CCl4 (Walker et al., 2000).

References

References

1. Touloukian, Y.S., Liley, P.E., and Saxena, S.C. Thermophysical properties of matter - the TPRC data series. Volume 3. Thermal conductivity - nonmetallic liquids and gases. Data book. 1970.
2. (1987). "The Properties of Gases and Liquids". McGraw-Hill Book Company.
3. "Carbon tetrachloride".
4. [https://fscimage.fishersci.com/msds/90116.htm Carbon Tetrachloride MSDS from Fisher Scientific]
5. {{PGCH. 0107
6. {{IDLH. 56235. Carbon tetrachloride
7. Smith, Michael, March, Jerry (2007). March’s Advanced Organic Chemistry : Reactions, Mechanisms, and Structure. 6th ed. Hoboken, N.J.: John Wiley & Sons. pp. 25-26
8. (2013). "Carbon Tetrachloride, in The Merck Index". Royal Society of Chemistry.
9. "Carbon Tetrachloride".
10. F. Brezina, J. Mollin, R. Pastorek, Z. Sindelar. ''Chemicke tabulky anorganickych sloucenin'' (''Chemical tables of inorganic compounds''). SNTL, 1986.
11. (March 1998). "Degradation of carbon tetrachloride by iron metal: Complexation effects on the oxide surface". Journal of Contaminant Hydrology.
12. "Carbonic Dichloride". Tidy, C. M. (1887). Handbook of modern chemistry, inorganic and organic. UK: Smith, Elder & Company. p. 215
13. Wislicenus, J., Strecker, A., Hodgkinson, W. R. E. (1882). Adolph Strecker's Short Text-book of Organic Chemistry. USA: D. Appleton.
14. Watts, H. (1872). A Dictionary of Chemistry. UK: Longman, Green, Roberts & Green.
15. Graham-Otto's ausführliches Lehrbuch der Chemie. (1881). Germany: Vieweg.
16. Faraday, Michael. (1859). "Experimental Researches in Chemistry and Physics". Taylor and Francis.
17. Turner, Edward. Elements of Chemistry: Including the Recent Discoveries and Doctrines of the Science. United Kingdom, John Taylor, 1834. Page 247
18. Graham, T., Watts, H. (1850). Elements of Chemistry: Including the Applications of the Science in the Arts. USA: Baillière.
19. Manfred Rossberg, Wilhelm Lendle, Gerhard Pfleiderer, Adolf Tögel, Eberhard-Ludwig Dreher, Ernst Langer, Heinz Jaerts, Peter Kleinschmidt, Heinz Strack, Richard Cook, Uwe Beck, Karl-August Lipper, Theodore R. Torkelson, Eckhard Löser, Klaus K. Beutel, "Chlorinated Hydrocarbons" in Ullmann's Encyclopedia of Industrial Chemistry, 2006 Wiley-VCH, Weinheim. {{doi. 10.1002/14356007.a06_233.pub2
20. "Preliminary Information on Manufacturing, Processing, Distribution, Use, and Disposal: Carbon Tetrachloride".
21. Gribble, G. W.. (1996). "Naturally occurring organohalogen compounds – A comprehensive survey". Progress in the Chemistry of Organic Natural Products.
22. Gribble, G. (2012). Progress in the Chemistry of Organic Natural Products. Austria: Springer Vienna.
23. Kinghorn, A. D., Falk, H., Gibbons, S., Asakawa, Y., Liu, J.-K., & Dirsch, V. M. (2023). Naturally occurring organohalogen compounds. Springer. p. 13
24. Burke, Robert. (2007-11-06). "Fire Protection: Systems and Response". CRC Press.
25. (October 1920). "Poisonous gases from carbon tetrachloride fire extinguishers". Journal of the Franklin Institute.
26. (2021). "15th Report on Carcinogens, Carbon Tetrachloride". National Toxicology Program.
27. "Environmental Health Criteria 208: CARBON TETRACHLORIDE". who.int.
28. (November 2025). "Public Health Statement for Carbon Tetrachloride (Tetracloruro de Carbono)". atsdr.cdc.gov }}{{Dead link.
29. [http://fscimage.fishersci.com/msds/90116.htm Material Safety Data Sheet, Carbon tetrachloride] {{webarchive. link. (2010-09-13 at Fisher Scientific.)
30. Toxicological Profile for Carbon Tetrachloride. (2005). USA: Agency for Toxic Substances and Disease Registry.
31. "Substance evaluation - CoRAP - ECHA".
32. The Atlas of Climate Change (2006) by [[Kirstin Dow]] and Thomas E. Downing {{ISBN. 978-0-520-25558-6
33. Doherty R. E.. (2000). "A History of the Production and Use of Carbon Tetrachloride, Tetrachloroethylene, Trichloroethylene and 1,1,1-Trichloroethane in the United States: Part 1—Historical Background; Carbon Tetrachloride and Tetrachloroethylene". Environmental Forensics.
34. (1955). "Attempt to Detect the Antineutrinos from a Nuclear Reactor by the Cl³⁷⁢ (𝜈,𝑒⁻) ⁢A³⁷ Reaction". Physical Review.
35. Neueste Erfindungen und Erfahrungen Auf Den Gebieten Der Praktischen Technik, Elektrotechnik, Der Gewerbe, Industrie, Chemie, Der Land und Hauswirthschaft. (1895). Austria: (n.p.).
36. (1941). "First Aid for Typewriters". Popular Science Monthly.
37. It had the downsides of being corrosive to the dry-cleaning equipment and causing illness among dry-cleaning operators, and was replaced by less toxic and overall safer solvents such as [[trichloroethylene]], [[tetrachloroethylene]][https://inchem.org/documents/iarc/vol63/dry-cleaning.html "DRY CLEANING IARC"]
38. Health and Safety Guide for Laundries and Dry Cleaners. (1975) U.S. Department of Health, Education, and Welfare, Public Health Service, Center for Disease Control, National Institute for Occupational Safety and Health, Division of Technical Services.
39. Pharmaceutical Journal: A Weekly Record of Pharmacy and Allied Sciences. (1909). UK: J. Churchill.
40. Meeker, R., Hamilton, A. (1915). Industrial Poisons Used in the Rubber Industry. U.S. Government Printing Office.
41. Report of the TEAP, May 2006 Progress Report. (2006). Kenya: United Nations Environment Programme Ozone Secretariat.
42. "The Tetrachloride of Carbon as an Anaesthetic", Dr Protheroe Smith, British Journal of Dental Science and Prosthetics (1867). UK: J. P. Segg & Company, page 302
43. ''On the Anaesthetic Use of Terchloride and Protochloride of Carbon'' The Lancet. UK, J. Onwhyn, 1848.
44. ''Mr Nunneley on Anaesthesia and Anaesthetic Substances'' Edinburgh medical and surgical journal (1849). UK
45. "A New Anaesthetic", British Journal of Dental Science and Prosthetics (1867). UK: J. P. Segg & Company, page 239
46. Notes on the anaesthetic properties of the Bichloride of Carbon by Arthur Ernest Sansom, Transactions of the Obstetrical Society of London. (1867) UK: Longmans, Green and Company.
47. Pages 170-173, "Anaesthetic and Sedative Properties of Bichloride of Carbon, or Chlorocarbon" (December 1865), Simpson, J. Y., Anaesthesia, Hospitalism, Hermaphroditism, and a Proposal to Stamp Out Small-pox and Other Contagious Diseases. (1871( UK: Adam and Charles Black.
48. Its anaesthetic action was likened to [[diethyl ether
49. Browning, E. (1940). Modern Drugs in General Practice.
50. Tropical Diseases Bulletin (1927) UK: Bureau of Hygiene and Tropical Diseases.
51. Taeger, H. (2013) Die Klinik der entschädigungspflichtigen Berufskrankheiten. Germany: Springer Berlin Heidelberg.
52. Tropical Diseases Bulletin (1925) UK: Bureau of Hygiene and Tropical Diseases.
53. Manson-Bahr, P. H., Manson, P. (1954). Manson's Tropical Diseases: A Manual of the Diseases of Warm Climates.
54. W. Reusch. "Introduction to Nuclear Magnetic Resonance Spectroscopy". [[Michigan State University]].
55. [http://www.norden.org/pub/ebook/2003-516.pdf Use of Ozone Depleting Substances in Laboratories. TemaNord 516/2003.] {{webarchive. link. (February 27, 2008)
56. {{US patent. 1010870, filed April 5, 1910.
57. {{US patent. 1105263, filed Jan 7, 1911.
58. Burke, Robert. (2007-11-06). "Fire Protection: Systems and Response". CRC Press.
59. Hazards of Carbon Tetrachloride Fire Extinguishers: Recommended Practices Number 3. USA, The Council, 1967.
60. (2018-08-09). "ACSH Explains: What's The Story On Carbon Tetrachloride?".
61. (1986). "Synergistic neurotoxicity of carbon tetrachloride/carbon disulfide (80/20 fumigants) and other pesticides in grain storage workers". Acta Pharmacologica et Toxicologica.
62. Darst, Guy. (1985-02-12). "Manufacturers Take Grain Fumigant Off Market in Face of EPA Testing". AP News.
63. ''COMMERCIAL PRODUCTS'' Morgan, D. P. (1996). Recognition and Management of Pesticide Poisonings. (n.p.): DIANE Publishing Company.
64. Hearings, Reports and Prints of the Senate Committee on Government Operations (1964). U.S. Government Printing Office.
65. Plant Protection and Quarantine Treatment Manual. (1976). U.S. Department of Agriculture, Animal and Plant Health Inspection Service, Plant Protection and Quarantine Programs.
66. (2011). "Le cercle des «phrères» disparus".
67. (23 October 2020). "Marvel Official MCU Spider-Man Web Fluid Formula".
68. de Prinse, Tom. (22 September 2019). "Illegal Chemical from a Vintage 1960s Extinguisher".
69. de Prinse, Tom. (27 March 2020). "Mixing Sodium and Chlorinated Solvents is Real Bad (Carbon Tetrachloride and Sodium)".
70. Bessman, Jim (1993). ''Ramones: An American Band.'' St. Martin's Griffin. p74.
71. "Evelyn Hermia (1917 - 1944)".
72. Okuda, Ted. (1986). "The Columbia Comedy Shorts". McFarland & Company, Inc., Publishers.
73. Glen, John M.. (1996). "Highlander: No Ordinary School, 2nd ed.". University of Tennessee Press.
74. "Margo Jones Theatre To Suspend on Dec. 15". The New York Times.
75. ''Certificate of Death: James A. Beck,'' Texas Department of Health, Bureau of Vital Statistics, File #24027
76. "Tommy Tucker". Soulfulkindamusic.net.
77. (January 25, 1982). "Robert Higginbotham, Singer Of Blues and Jazz, Dead at 48". [[The New York Times]].