blood alcohol concentration

biochemistry

Also known as: BAC, blood alcohol content

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Last updated

July 16, 2026

Quick Summary

Blood alcohol concentration (BAC) is a measure of the amount of alcohol in a person's bloodstream. Alcohol is absorbed primarily through the stomach and small intestine and metabolized in the liver. The liver converts alcohol to acetaldehyde, then to acetate

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alcohol consumption
Blood alcohol concentration
Because brain alcohol concentrations are difficult to measure directly, the effects of alcohol on the brain are calculated indirectly by noting the physical and mental impairments that typically arise at various levels of blood alcohol concentration, or BAC.
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Because brain alcohol concentrations are difficult to measure directly, the effects of alcohol on the brain are calculated indirectly by noting the physical and mental impairments that typically arise at various levels of blood alcohol concentration, or BAC.
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alcohol consumption
United States
…lowered the legal limit of blood alcohol content (BAC) for drivers from 0.10 mg of alcohol per 100 ml of blood to 0.08 and increased the penalties for driving under the influence.
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…lowered the legal limit of blood alcohol content (BAC) for drivers from 0.10 mg of alcohol per 100 ml of blood to 0.08 and increased the penalties for driving under the influence.
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