Blood Alcohol Concentration

Blood Alcohol Concentration (BAC)

Definition: the amount of alcohol in the bloodstream which is measured in percentages. For example, a person with BAC of 0.10 percent means there is 1 part alcohol per 1,000 parts blood in the body.

Most States have a legal BAC standard of 0.08 percent.
In studies impairment is first seen at blood alcohol concentrations of 0.02 percent which shows that one does not have to be intoxicated to demonstrate impairment.
BAC can be measured by testing breath, urine or blood.
BAC is most commonly linked with drunk driving and is important in determining the role alcohol could have played in accidents, violence and crimes.

This table gives an idea of the blood alcohol content determined by
the individual’s weight and number of drinks consumed.

Factors that affect BAC…

Amount of alcohol one consumes.
Body weight.
Lighter people are more affected by the same amount of alcohol than heavier people. Heavier people have more blood and water in their bodies in which the alcohol can circulate. In other words, the alcohol will make up a smaller percent of the fluid.
Food in the stomach. Alcohol is absorbed more slowly into the blood stream when food is present in the stomach, so the BAC rises more slowly.
Sex.
Females reach higher BAC’s more quickly because they have less water in their bodies and more fat tissue, which the alcohol cannot pass through very easily. A woman will also experience her highest BAC’s premenstrually. In addition, a woman taking birth control pills, might absorb alcohol faster.
Rate of consumption.
The faster one drinks, the higher the peak BAC. The liver processes alcohol at about one drink per hour (5 oz. wine, 12 oz. beer, 1 shot of liquor). Drinking faster than this causes the remaining alcohol to circulate in the blood until the liver can deal with it.
Temperature of drink.
Warm alcohol is absorbed more quickly.
Type of alcohol.
The higher the alcohol concentration, (1^st: distilled alcohol, 2^nd: wine, 3^rd: beer) the faster the rate of absorption.
Type of mixer.
Juices and water with alcohol slow the absorption process; carbonated beverages hasten the process. Carbon dioxide speeds alcohol through to the bloodstream, producing a rapid rise in BAC.