Alcohol Facts by National Draeger
Endogenous Alcohol
Endogenous alcohol refers to alcohol that exists "normally" in the body regardless of whether or not a person consumes alcoholic beverages. There is considerable disagreement among experts regarding the existence of "normal" alcohol in the body; however, both "normal" methyl and ethyl alcohol have been reported in the research literature. The values reported have not exceeded a BAC of 0.003% and generally are less than 0.001%. These values are about the same as those reported for "normal" lead, arsenic and mercury. They are generally too low to be of any medicolegal significance and are of academic interest only.
Physiology Overview
The course of alcohol in the human body is shown in Exhibit C-2. A brief description of absorption, distribution and elimination of alcohol is given below.
Absorption
Alcohol is typically swallowed and travels from the mouth through the esophagus to the stomach. Here part of the alcohol is absorbed directly into the blood stream by the process of diffusion; the remainder is absorbed in the small intestine. The rate of flow from the stomach to the small intestine is controlled by the pylorus, which opens and closes at the base of the stomach to permit or inhibit the passage of solids and liquids.
Distribution
The alcohol travels from the stomach and small intestine via the portal vein to the liver. From the liver, it travels to the heart, the lungs, and back to the heart from which it is pumped to all parts of the body. Alcohol has an affinity for water and is stored in the body tissues in proportion to their fluid content.
Elimination
Once absorbed into the blood stream, the body immediately starts to eliminate the alcohol. This is largely accomplished in the liver where the alcohol is oxidized to carbon dioxide and water. Some small portion (less than 10%) is eliminated directly through urine, breath, perspiration, tears and saliva.
