The use of Ethanol

Ethanol (also called ethyl alcohol, grain alcohol, drinking alcohol, or simply alcohol) is an organic chemical compound. It is a simple alcohol with the chemical formula C2H6O. Ethanol is a volatile, flammable, colorless liquid with a characteristic wine-like odor and pungent taste.It is a psychoactive drug, recreational drug, and the active ingredient in alcoholic drinks.

Ethanol is naturally produced by the fermentation of sugars by yeasts or via petrochemical processes such as ethylene hydration. It has medical applications as an antiseptic and disinfectant. It is used as a chemical solvent and in the synthesis of organic compounds. Ethanol is a fuel source.

Uses

Medical

Main article: Alcohol (medicine)

Antiseptic

Ethanol is used in medical wipes and most commonly in antibacterial hand sanitizer gels as an antiseptic for its bactericidal and anti-fungal effects. Ethanol kills microorganisms by dissolving their membrane lipid bilayer and denaturing their proteins, and is effective against most bacteria, fungi and viruses. However, it is ineffective against bacterial spores, but that can be alleviated by using hydrogen peroxide.A solution of 70% ethanol is more effective than pure ethanol because ethanol relies on water molecules for optimal antimicrobial activity. Absolute ethanol may inactivate microbes without destroying them because the alcohol is unable to fully permeate the microbe's membrane.Ethanol can also be used as a disinfectant and antiseptic because it causes cell dehydration by disrupting the osmotic balance across cell membrane, so water leaves the cell leading to cell death.

Antidote

Ethanol may be administered as an antidote to ethylene glycol poisoning and methanol poisoning.

Medicinal solvent

Ethanol, often in high concentrations, is used to dissolve many water-insoluble medications and related compounds. Liquid preparations of pain medications, cough and cold medicines, and mouth washes, for example, may contain up to 25% ethanol and may need to be avoided in individuals with adverse reactions to ethanol such as alcohol-induced respiratory reactions.Ethanol is present mainly as an antimicrobial preservative in over 700 liquid preparations of medicine including acetaminophen, iron supplements, ranitidine, furosemide, mannitol, phenobarbital, trimethoprim/sulfamethoxazole and over-the-counter cough medicine.

Pharmacology

In mammals, ethanol is primarily metabolized in the liver and stomach by alcohol dehydrogenase (ADH) enzymes. These enzymes catalyze the oxidation of ethanol into acetaldehyde (ethanal):

CH3CH2OH + NAD+ → CH3CHO + NADH + H+

When present in significant concentrations, this metabolism of ethanol is additionally aided by the cytochrome P450 enzyme CYP2E1 in humans, while trace amounts are also metabolized by catalase.[31]

The resulting intermediate, acetaldehyde, is a known carcinogen, and poses significantly greater toxicity in humans than ethanol itself. Many of the symptoms typically associated with alcohol intoxication — as well as many of the health hazards typically associated with the long-term consumption of ethanol — can be attributed to acetaldehyde toxicity in humans.

The subsequent oxidation of acetaldehyde into acetate is performed by aldehyde dehydrogenase (ALDH) enzymes. A mutation in the ALDH2 gene that encodes for an inactive or dysfunctional form of this enzyme affects roughly 50% of east Asian populations, contributing to the characteristic alcohol flush reaction that can cause temporary reddening of the skin as well as a number of related, and often unpleasant, symptoms of acetaldehyde toxicity.[33] This mutation is typically accompanied by another mutation in the alcohol dehydrogenase enzyme ADH1B in roughly 80% of east Asians, which improves the catalytic efficiency of converting ethanol into acetaldehyde.

Recreational

Main articles: Alcohol (drug) and Alcoholic drink

As a central nervous system depressant, ethanol is one of the most commonly consumed psychoactive drugs.

Despite alcohol's psychoactive properties, it is readily available and legal for sale in most countries. However, there are laws regulating the sale, exportation/importation, taxation, manufacturing, consumption, and possession of alcoholic beverages. The most common regulation is prohibition for minors.