Scientific Evidence in California Criminal Cases – Evidence of Alcohol Intoxication
6.3 C. Abortion of Alcohol
Since the majority of the alcohol absorption occurs in the small intestine, food becomes relevant factor in the consideration of alcohol absorption. Any delay in the absorption of alcohol will result in a delay in the perceived effects by the brain and judgment of the drinker. In order to effectively interpret a particular blood alcohol result, it is important to know whether a breath sample was collected during the absorptive phase or sometime thereafter. Many experts will not attest to the reliability of breath results collected during the absorptive phase as they may over report the actual blood concentration (as measured by a venous blood sample) by as much as 100 percent or more. Simpson, Accuracy and Precision of Breath Alcohol Measurements for Subjects in the Absorptive State, 22 Clinical Chemistry 753, 755 (June 1987) for the online version of this article, go to http://clinchem.org/cgi/reprint/33/6/753.htm
The rate at which the body absorbs alcohol varies from person to person. In addition, a variety of factors can influence the rate at which an individual absorbs alcohol on any particular occasion. Because most alcohol abortion occurs in the small intestine, after the alcohol has left the stomach, any factor delays the passage of the contents of the stomach into the small intestine will slow absorption. See Boggan, Alcohol, Chemistry and You: Absorption of Ethyl Alcohol, Kennesaw State U (2003); for the online version of this article, go to http://chemcases.com/alcohol/alc-04.htm.
The most significant factor affecting the rate at which alcohol is absorbed is the presence or absence of food in the stomach. Food in the stomach, whether consumed before or during the consumption of alcohol, will slow its absorption. The rate of absorption depends mainly on the amount of food consumed. The type of food consumed (heavy, fatty, or high in carbohydrates or calories) may also play a role. In addition to slowing absorption, the presence of food has been found to increase elimination rates. Ramchandani, Kwo & Li, Effect of Food and Food Composition on Alcohol Elimination Rates in Healthy Men and Women, 41(12) J Clinical Pharmacology 1345, 1348 (2001); for the online version of this article, go to http://jcp/sagepub.com/cgi/reprint/41/12/1345.
Depending on varies factors, the full absorption of alcohol may not be reached until after 2-3 hours. Normally, however when people drink socially, it can take up to 105 minutes after the cessation of drinking to reach BAC. Saferstein, Criminalistics; An Introduction to Forensic Science, chap 9 (10th ed 2011) See also Jones, Honsoon & Neri, Peak Blood Ethanol Concentrations and the time of its Occurrence After Rapid Drinking on an Empty Stomach, 36 (2) J Forensic Sci 376 (Mar. 1991)
Other factors may also affect the rate at which alcohol is absorbed. Some studies have indicated that high concentration of alcohol irritate the stomach lining and slow gastric emptying. Beer, with its low alcohol content and high level of carbohydrates, may be absorbed more slowly than other alcoholic beverages. Smocking, drinking a larger volume in shorter periods of time, trauma, shock, and blood loss are also believed to slow absorption. See Garriott. ed., Medical-Legal Aspects of Alcohol, chaps 3-4 (4th ed 2003).
Certain prescriprtion drugs have been shown to delay gastric empty-ing hall. Nausea; shock, anticholinergic agents, which decrease gastrointestinal (GI) motility, pain; fear; sympathomimetic agents (used as decongestants and to treat asthma), which decrease GI Blood flow; stimulants; excercise; emotional disturbance; gastric fibrosis; and carcinomatosis can delay gastric emptying. In addition, a variety of factors, for example, chronic gastritis, gastric ulcers, ingestion of warm liquids or food, stress, anxiety, fever, carbonation in teh beverage, chronic alcoholism, and gastrectomy, have been shown to increase the rate of absorption. Cooper, Schwar & Smith, Alcohol, Drugs, and Road Traffic (1979)
Absorption ends when the level of alcohol in the gastrointestinal system is at equilibrium with the rest of the body. Many of the emotional factors that teh DUI suspects expereiences during the stop and investigatory portion of the arrest may inadvertently affect the final blood alcohol determination. Choices made during the course of the drinking session (including what type of beverage to consume, and when and what to eat during the session) also contribute to the BAC both at the time of driving and at the time of the actual evidentiary measurement.
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