Published by Australian Academy of Science
Glossary | The dope on drug-impaired driving

blood alcohol content (BAC). The concentration of ethanol in the blood, which is a key measure in determining the effect of ethanol on the body. It is measured in grams of ethanol per 100 millilitres of blood. For example, people with a BAC of 0.05 grams per 100 millilitres – the legal limit for most drivers – have 0.05 grams of alcohol in their body for every 100 millilitres of their blood.

depressant. A substance that slows down the functions of the central nervous system. More information can be found at About drugs (Australian Drug Foundation).

hallucinogen. A substance that alters perception and can induce delusions or hallucinations. More information can be found at Hallucinogens (New South Wales Department of Health, Australia).

immunoassay. A laboratory test that uses antibodies to identify and quantify substances. Often the antibody is linked to a marker such as a fluorescent molecule, a radioactive molecule, or an enzyme.

stimulant. A substance that speed up the functions of the central nervous system. For more information see Stimulants (Missouri Department of Mental Health, USA).