USES OF ALCOHOL

Alcohol is a general term denoting a family of organic chemicals with common properties. Members of this family include ethanol, methanol, isopropanol, and others. This introduction discusses the physical, chemical, and physiological aspects of the most commonly ingested of these - ethanol.

Alcohol (ethanol) is a clear, volatile liquid that burns (oxidizes) easily. It has a slight, characteristic odor and is very soluble in water. Alcohol is an organic compound composed of carbon, oxygen, and hydrogen; its chemical formula is C2H5OH.
Alcohol is a central nervous system depressant and it is the central nervous system which is the bodily system that is most severely affected by alcohol (see chart below). The degree to which the central nervous system function is impaired is directly proportional to the concentration of alcohol in the blood.

When ingested, alcohol passes from the stomach into the small intestine, where it is rapidly absorbed into the blood and distributed throughout the body. Because it is distributed so quickly and thoroughly the alcohol can affect the central nervous system even in small concentrations. In low concentrations, alcohol reduces inhibitions. As blood alcohol concentration increases, a person's response to stimuli decreases markedly, speech becomes slurred, and he or she becomes unsteady and has trouble walking. With very high concentrations - greater than 0.35 grams/100 milliliters of blood (equivalent to 0.35 grams/210 liters of breath ) - a person can become comatose and die. The American Medical Association has defined the blood alcohol concentration level of impairment for all people to be 0.04 grams/100 milliliters of blood (equivalent to .04 grams/210 liters of breath). The following is a generally accepted guide to the effects of alcohol.
Stages of alcohol intoxication
BAC (g/100 ml of bloodor g/210 l of breath) Stage
Clinical symptoms

0.01 - 0.05 Subclinical
Behavior nearly normal by ordinary observation

0.03 - 0.12 Euphoria
Mild euphoria, sociability, talkitivenessIncreased self-confidence; decreased inhibitionsDiminution of attention, judgment and controlBeginning of sensory-motor impairmentLoss of efficiency in finer performance tests

0.09 - 0.25 Excitement
Emotional instability; loss of critical judgmentImpairment of perception, memory and comprehensionDecreased sensitory response; increased reaction timeReduced visual acuity; peripheral vision and glare recoverySensory-motor incoordination; impaired balanceDrowsiness

0.18 - 0.30 Confusion
Disorientation, mental confusion; dizzinessExaggerated emotional statesDisturbances of vision and of perception of color, form, motion and dimensionsIncreased pain thresholdIncreased muscular incoordination; staggering gait; slurred speechApathy, lethargy

0.25 - 0.40 Stupor
General inertia; approaching loss of motor functionsMarkedly decreased response to stimuliMarked muscular incoordination; inability to stand or walkVomiting; incontinenceImpaired consciousness; sleep or stupor

0.35 - 0.50 Coma
Complete unconsciousnessDepressed or abolished reflexesSubnormal body temperatureIncontinenceImpairment of circulation and respirationPossible death

0.45 + Death
Death from respiratory arrest

Alcohol Use and Drinking ProblemsAlcohol Equivalencies:

As shown in the following diagram, the absolute amount of ethyl alcohol that a drinker consumes is approximately the same for a 5 ounce glass of wine, a 12 ounce can or bottle of beer, and a standard shot of distilled spirits. In each case, one drink equals a little more than a half-ounce of alcohol. Of course, the larger the wine glass or beer bottle, the greater the amount of alcohol. Also, some beverages such as fortified wines and malt liquor contain more alcohol by volume than ordinary wine or beer.

Blood Alcohol Concentration:

An individual's Blood Alcohol Concentration (BAC) is a function of a number of factors, including gender, body weight, and number of drinks consumed within a period of time. The following table shows how absolute BAC varies as a function of those three variables. In addition, BAC can depend upon whether alcohol is consumed with a meal and whether the beverage is carbonated (e.g., sparkling wine). In most people, the liver is able to metabolize slightly less than half an ounce of alcohol per hour. The table shows BAC for number of drinks consumed in one hour.