The chemical

When we talk about alcohol most of us are referring to the alcohol in drinks - known as ethanol. In science and industry the word alcohol refers to a group of compounds made up of a hydrocarbon chain with a hydroxyl (OH) group attached at one end. Ethanol is a member of the alcohol group, other examples are methanol, propanol and pentanol.

The chemical structure of ethanol
 


Alcohol looks fairly harmless when drawn like this, so it's hard to believe that this small compound is responsible for an annual 30 billion economy and is reckoned to cost us 20 billion each year in alcohol related harm. This small molecule clearly has a big impact.
     
   

The name

There are two theories to explain the origins of the word. It is thought to be Arabic and could have started as Al-kuhul, the Arabic for antimony sulphide, a chemical used as an antiseptic and eyeliner which is also made by distillation. The second theory suggests the word is a mixture of Al-Kuhul, and Al-ghawl meaning spirit, or the headiness of wine.

     
   

Toxicity

Ethanol has been consumed in the form of alcoholic drinks since pre-historic times, for a variety of hygienic, dietary, medicinal, religious and recreational purposes. While small amounts now and then may have no effect, larger doses can cause many problems.

The other alcohols are far more poisonous than ethanol. Methanol is broken down in the body to the highly poisonous formaldehyde, which cause blindness or death. Surprisingly the best treatment for methanol poisoning is ethanol, which is broken down by the body instead of the methanol.