Acetone

In chemistry, acetone (also known as propanone, dimethyl ketone, 2-propanone, propan-2-one and beta-ketopropane) is the simplest representative of the ketones.

Acetone is a colourless mobile flammable liquid with melting point at -95.4 °C and boiling point at 56.53 °C. It has a relative density of 0.819 (at 0 °C). It is readily soluble in water, ethanol, ether, etc., and itself serves as an important solvent. The most familiar household use of acetone is as the active ingredient in nail polish remover. Acetone is also used to make plastic, fibers, drugs, and other chemicals.

Biological aspects

As a member of the ketone bodies it is present in very small quantity in normal urine and in the blood. Larger quantities can be found after starvation and in diabetic patients with severe insulin deficiency (that is untreated or inadequately treated persons); a fruity smell of the breath caused by acetone is one symptom of diabetic ketoacidosis. See ketone bodies for more information.

Acetone occurs naturally in plants, trees, volcanic gases, forest fires, and as a product of the breakdown of body fat. It is present in vehicle exhaust, tobacco smoke, and landfill sites. Industrial processes contribute more acetone to the environment than natural processes. It is found among the products formed in destructive distillation of wood, sugar, cellulose, etc., and for this reason it is always present in crude wood spirit, from which the greater portion of it may be recovered by fractional distillation.

Chemistry

It forms a hydrazone with phenyl hydrazine and an oxime with hydroxylamine. Reduction by sodium amalgam converts it into isopropyl alcohol; oxidation by chromic acid gives carbon dioxide and acetic acid. It reacts with ammonia to form di- and triacetoneamines. It also unites directly with hydrocyanic acid to form the nitrile of α-oxyisobutyric acid.

By the action of various reagents, such as lime, caustic potash, hydrochloric acid, etc., acetone is converted into condensation products, mesityl oxide C₆H₁₀O, phorone C₉H₁₄O, etc., being formed. On distillation with sulfuric acid (H₂SO₄), it is converted into mesitylene C₉H₁₂ (symmetrical trimethylbenzene). Acetone has also been used in the artificial production of indigo. In the presence of iodine and an alkali it gives iodoform.

Uses

An important industrial use for acetone its reaction with phenol, used for the manufacture of bisphenol A. Bisphenol A is an important component of many polymers such as polycarbonates, polyurethanes and epoxy resins.

Health effects

Swallowing very high levels of acetone can result in unconsciousness and damage to the skin in the mouth. Skin contact can result in irritation and damage to the skin.

The smell and respiratory data are known mostly from animal studies. Kidney, liver, and nerve damage, increased birth defects, and lowered reproduction ability of males (only) occurred in animals exposed long-term. It is not known if these same effects would be exhibited in humans.

Interestingly, acetone has been shown to have anticonvulsant effects in animal models of epilepsy, in the absence of toxicity, when administered in millimolar concentrations (see: Likhodii et al, 2003).