Denatured alcohol, also known as methylated spirits, metho, or meths in Australia, Ireland, New Zealand, South Africa, and the United Kingdom, and as denatured rectified spirit, is

ethanol Ethanol (also called ethyl alcohol, grain alcohol, drinking alcohol, or simply alcohol) is an organic compound with the chemical formula . It is an Alcohol (chemistry), alcohol, with its formula also written as , or EtOH, where Et is the ps ...

that has additives to make it

poison 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 figurati ...

ous, bad-tasting, foul-smelling, or nauseating to discourage its recreational consumption. It is sometimes dyed so that it can be identified visually.

Pyridine Pyridine is a basic (chemistry), basic heterocyclic compound, heterocyclic organic compound with the chemical formula . It is structurally related to benzene, with one methine group replaced by a nitrogen atom . It is a highly flammable, weak ...

and

methanol Methanol (also called methyl alcohol and wood spirit, amongst other names) is an organic chemical compound and the simplest aliphatic Alcohol (chemistry), alcohol, with the chemical formula (a methyl group linked to a hydroxyl group, often ab ...

, each and together, make denatured alcohol poisonous;

denatonium Denatonium, usually available as denatonium benzoate (under trade names such as Denatrol, BITTERANT-b, BITTER+PLUS, Bitrex, Bitrix, and Aversion) and as denatonium saccharinate (BITTERANT-s), is the bitterest chemical compound known, with bittern ...

makes it bitter. Denatured alcohol is used as a

solvent A solvent (from the Latin language, Latin ''wikt:solvo#Latin, solvō'', "loosen, untie, solve") is a substance that dissolves a solute, resulting in a Solution (chemistry), solution. A solvent is usually a liquid but can also be a solid, a gas ...

and as fuel for

alcohol burner An alcohol burner or spirit lamp is a piece of laboratory equipment used to produce an open flame. It can be made from brass, glass, stainless steel or aluminium. Uses Alcohol burners are preferred for some uses over Bunsen burners for safety pu ...

s and

camping stove A portable stove is a cooking stove specially designed to be portable and lightweight, used in camping, picnicking, backpacking, or other use in remote locations where an easily transportable means of cooking or heating is needed. Portable stove ...

s. Because of the diversity of industrial uses for denatured alcohol, hundreds of additives and denaturing methods have been used. The main additive usually is 10% methanol (methyl alcohol), hence the name ''methylated spirits''. Other common additives include

isopropyl alcohol Isopropyl alcohol (IUPAC name propan-2-ol and also called isopropanol or 2-propanol) is a colorless, flammable, organic compound with a pungent alcoholic odor. Isopropyl alcohol, an organic polar molecule, is miscible in water, ethanol, an ...

acetone Acetone (2-propanone or dimethyl ketone) is an organic compound with the chemical formula, formula . It is the simplest and smallest ketone (). It is a colorless, highly Volatile organic compound, volatile, and flammable liquid with a charact ...

methyl ethyl ketone Butanone, also known as methyl ethyl ketone (MEK) or ethyl methyl ketone, is an organic compound with the formula CH3C(O)CH2CH3. This colorless liquid ketone has a sharp, sweet odor reminiscent of acetone. It is produced industrially on a large s ...

, and

methyl isobutyl ketone Methyl isobutyl ketone (MIBK, 4-methylpentan-2-one) is an organic compound with the structural formula, condensed chemical formula (CH3)2CHCH2C(O)CH3. This ketone is a colourless liquid that is used as a solvent for gums, resins, paints, varnishes ...

. Denaturing alcohol does not alter the ethanol molecule (

chemically A chemical reaction is a process that leads to the chemical transformation of one set of chemical substances to another. When chemical reactions occur, the atoms are rearranged and the reaction is accompanied by an energy change as new products ...

or structurally), unlike denaturation in biochemistry. Rather, the ethanol is mixed with other chemicals to form a foul-tasting, often toxic, solution. For many of these solutions, it is intentionally difficult to separate the components. Denaturat_1

In many countries denaturated alcohol is traditionally dyed with

methyl violet Methyl violet is a family of organic compounds that are mainly used as dyes. Depending on the number of attached methyl groups, the color of the dye can be altered. Its main use is as a purple dye for textiles and to give deep violet colors in pain ...

or similar hue (

crystal violet Crystal violet or gentian violet, also known as methyl violet 10B or hexamethyl pararosaniline chloride, is a triphenylmethane, triarylmethane dye used as a histological stain and in Gram staining, Gram's method of classifying bacteria. Crystal ...

methylene blue Methylthioninium chloride, commonly called methylene blue, is a salt used as a dye and as a medication. As a medication, it is mainly used to treat methemoglobinemia. It has previously been used for treating cyanide poisoning and urinary trac ...

) dye for safety reasons. In

Central and Eastern Europe Central and Eastern Europe is a geopolitical term encompassing the countries in Baltic region, Northeast Europe (primarily the Baltic states, Baltics), Central Europe (primarily the Visegrád Group), Eastern Europe, and Southeast Europe (primaril ...

(what are now) Czech Republic, Slovakia, Poland and others, this was mandatory during the

communist era A communist era is a sustained period of national government by a single party following the philosophy of Marxism–Leninism. Many countries have experienced such a period of communist rule. Current communist states China The Chinese Communist ...

Uses

In many countries, sales of alcoholic beverages are heavily

taxed A tax is a mandatory financial charge or levy imposed on an individual or legal entity by a governmental organization to support government spending and public expenditures collectively or to regulate and reduce negative externalities. Tax compl ...

for revenue and public health policy purposes (see

Pigovian tax A Pigouvian tax (also spelled Pigovian tax) is a tax on any market activity that generates negative externalities (i.e., external costs incurred by third parties that are not included in the market price). It is a method that tries to internal ...

). In order to avoid paying beverage taxes on alcohol that is not meant to be consumed, the alcohol is usually "denatured", or treated with added chemicals to make it unpalatable. Its composition is tightly defined by government regulations in countries that tax alcoholic beverages. Denatured alcohol is used identically to ethanol itself but only for applications that involve fuel, surgical and laboratory stock. Pure ethanol is required for food and beverage applications and certain chemical reactions where the denaturant would interfere. In

molecular biology Molecular biology is a branch of biology that seeks to understand the molecule, molecular basis of biological activity in and between Cell (biology), cells, including biomolecule, biomolecular synthesis, modification, mechanisms, and interactio ...

, denatured ethanol should not be used for the

precipitation In meteorology, precipitation is any product of the condensation of atmospheric water vapor that falls from clouds due to gravitational pull. The main forms of precipitation include drizzle, rain, rain and snow mixed ("sleet" in Commonwe ...

nucleic acid Nucleic acids are large biomolecules that are crucial in all cells and viruses. They are composed of nucleotides, which are the monomer components: a pentose, 5-carbon sugar, a phosphate group and a nitrogenous base. The two main classes of nuclei ...

s, since the additives may interfere with downstream applications. Denatured alcohol has no advantages for any purpose over normal ethanol; it is a public policy compromise. As denatured alcohol is sold without the often heavy taxes on

alcohol Alcohol may refer to: Common uses * Alcohol (chemistry), a class of compounds * Ethanol, one of several alcohols, commonly known as alcohol in everyday life ** Alcohol (drug), intoxicant found in alcoholic beverages ** Alcoholic beverage, an alco ...

suitable for consumption, it is a cheaper solution for most uses that do not involve drinking. If pure ethanol were made cheaply available for fuel, solvents, or medicinal purposes, it could be used as a beverage without payment of alcohol tax.

Toxicity

Despite its poisonous content, denatured alcohol is sometimes consumed as a

surrogate alcohol Surrogate alcohol is a term for any substance containing ethanol, or other alcohols, that is intentionally consumed by humans but is not meant for human consumption. Some definitions of the term also extend to illegally produced alcoholic beverag ...

. This can result in blindness or death if it contains methanol. For instance, during the thirteen-year

prohibition Prohibition is the act or practice of forbidding something by law; more particularly the term refers to the banning of the manufacture, storage (whether in barrels or in bottles), transportation, sale, possession, and consumption of alcoholic b ...

of alcohol in the US, federal law required methanol be added to domestically manufactured industrial alcohols. From 25–27 December 1926, which was roughly at the midpoint of nationwide alcohol prohibition, 31 people in New York City alone died of methanol poisoning. To help prevent this,

is often added to give the substance an extremely bitter flavour. Substances such as

pyridine Pyridine is a basic (chemistry), basic heterocyclic compound, heterocyclic organic compound with the chemical formula . It is structurally related to benzene, with one methine group replaced by a nitrogen atom . It is a highly flammable, weak ...

are added to give the mixture an unpleasant odour, and agents such as

syrup of ipecac Syrup of ipecac (), or simply ipecac, is a drug that was once widely used as an expectorant (in low doses) and a rapid-acting emetic (in higher doses). It is obtained from the dried rhizome and roots of the ipecacuanha plant ('' Carapichea ipe ...

may also be included to induce vomiting. New Zealand has removed methanol from its government-approved "methylated spirits" formulation. In the

USSR The Union of Soviet Socialist Republics. (USSR), commonly known as the Soviet Union, was a List of former transcontinental countries#Since 1700, transcontinental country that spanned much of Eurasia from 1922 until Dissolution of the Soviet ...

, denatured alcohol was used as drinking alcohol surrogate, along with many other technical ethanol-containing products. This was especially common during various anti-alcohol campaigns initiated by the Soviet government. There is much evidence to that in both popular folklore and in literature and music. The word "denaturat" (Russian: денатурат) even gained a special symbolic meaning. Its consumption is mentioned in songs of

Vladimir Vysotsky Vladimir Semyonovich Vysotsky (25 January 193825 July 1980) was a Soviet singer-songwriter, poet, and actor who had an immense and enduring effect on Soviet culture. He became widely known for his unique singing style and for his lyrics, which ...

, as well as written works of Venedikt Yerofeev,

Yuz Aleshkovsky Iosif Efimovich Aleshkovsky (), known as Yuz Aleshkovsky () (September 21, 1929 – March 21, 2022) was a modern Russian writer, poet, screenwriter, and bard, namely performer of his own songs. Biography Yuz Aleshkovsky was born in Krasnoyarsk, ...

, and Vyacheslav Shishkov.

Formulations

Diverse additives are used to make it difficult to use

distillation Distillation, also classical distillation, is the process of separating the component substances of a liquid mixture of two or more chemically discrete substances; the separation process is realized by way of the selective boiling of the mixt ...

or other simple processes to reverse the denaturation. Methanol is commonly used both because its boiling point is close to that of ethanol and because it is toxic. Another typical denaturant is pyridine. Often the denatured alcohol is dyed with

.Naim Kosaric, Zdravko Duvnjak, Adalbert Farkas, Hermann Sahm, Stephanie Bringer-Meyer, Otto Goebel and Dieter Mayer in "Ethanol" Ullmann's Encyclopedia of Industrial Chemistry, 2011, Wiley-VCH, Weinheim. There are several grades of denatured alcohol, but in general the denaturants used are similar. As an example, the formulation for ''completely denatured alcohol'', according to 2005 British regulations was as follows: The European Union agreed in February 2013 to the following mutual procedures for the complete denaturing of alcohol:

Specially denatured alcohol

A specially denatured alcohol (SDA) is one of many types of denatured alcohol specified under the United States

Title 27 of the Code of Federal Regulations CFR Title 27 – Alcohol, Tobacco Products and Firearms is one of 50 titles composing the United States Code of Federal Regulations (CFR) and contains the principal set of rules and regulations issued by federal agencies regarding alcohol, tobacco ...

Section 21.151. A specially denatured alcohol is a combination of ethanol and another chemical substance, e.g.,

ethyl acetate Ethyl acetate commonly abbreviated EtOAc, ETAC or EA) is the organic compound with the formula , simplified to . This flammable, colorless liquid has a characteristic sweet smell (similar to pear drops) and is used in glues, nail polish removers, ...

in SDA 29, 35, and 35A, added to render the mixture unsuitable for drinking. SDAs are often used in cosmetic products, and can also be used in chemical manufacturing, pharmaceuticals, and solvents. Another example is SDA 40-B, which contains

tert-butyl alcohol ''tert''-Butyl alcohol is the simplest tertiary alcohol, with a formula of (CH3)3COH (sometimes represented as ''t''-BuOH). Its isomers are 1-butanol, isobutanol, and butan-2-ol. ''tert''-Butyl alcohol is a colorless solid, which melts near ...

and denatonium benzoate, N.F. In the United States and other countries, the use of denatured alcohol unsuitable for beverages avoids

excise file:Lincoln Beer Stamp 1871.JPG, upright=1.2, 1871 U.S. Revenue stamp for 1/6 barrel of beer. Brewers would receive the stamp sheets, cut them into individual stamps, cancel them, and paste them over the Bunghole, bung of the beer barrel so when ...

taxes on alcohol.2004 CFR Title 27, Volume 1
. access.gpo.gov. Retrieved on 29 May 2011.

References

External links

{{Commons category, Denatured alcohol
27 CFR 20, regulations relating to denatured alcohol in the United States

Specifications and licensing of methylated spirits in the United Kingdom

European Community COMMISSION REGULATION (EC) No 162/2013 on the mutual recognition of procedures for the complete denaturing of alcohol for the purposes of exemption from excise duty
*

HM Revenue and Customs His Majesty's Revenue and Customs (commonly HM Revenue and Customs, or HMRC, and formerly Her Majesty's Revenue and Customs) is a department of the UK government responsible for the collection of taxes, the payment of some forms of stat ...