DUI Urine Tests

A lot of people ask, “How long does alcohol stay in your urine?” When ethyl alcohol is consumed, it is absorbed directly into the bloodstream and distributed by the blood circulatory system to all tissues and organs of the body, including the kidneys. Because alcohol is treated by the body as an impurity, small amounts of it are continually removed from the bloodstream by the kidneys. The alcohol that is removed by the kidneys passes through the ureter to the bladder, where all impurities removed by the kidneys are stored in the form of urine.

Urine, unlike blood, is never in direct contact with brain tissue and the concentration of alcohol in urine does not directly indicate the concentration of alcohol in brain tissue. The concentration of alcohol in urine only indicates the concentration of alcohol in a person’s blood. A measurement of urine alcohol concentration (UAC) is an indirect measurement of blood alcohol concentration (BAC), which is itself only an indirect measurement of intoxication.

The most important thing to remember about a DUI urine test is that it is generally considered to be an inherently unreliable and inaccurate method of determining a person’s degree of intoxication. Even the National Highway Traffic Safety Administration, the DUI-DWI arm of the federal government, concedes this unreliability.

A DUI urine test for alcohol is no longer used as a method of quantitative testing for ethyl alcohol in most states because of its deficiencies as an indicator of intoxication. However, because it is an inexpensive and sometimes convenient method of testing, it is still used in several states, especially where other drugs are suspected. It can be useful in rural areas without modern breath testing equipment or trained medical personnel. Also, the implied consent laws in a few states permit a person accused of a drunk driving offense to choose urine testing as the method of chemical testing, particularly if it is for an independent test.

The weaknesses of urine testing as a method of quantitative testing for alcohol in drinking-driving cases may be summarized as follows:

  1. The pooling of urine in the bladder causes UAC to be an unreliable indicator of BAC at any particular time.
  2. The UAC-to-BAC ratio varies considerably from person to person and from time to time for the same person, and there is no generally accepted ratio that is universally used.
  3. Endogenous alcohol is often formed in the urine of diabetics and persons with urinary tract infections, such as candida albicans.
  4. The procedures necessary to properly collect and preserve a sample of urine are time-consuming and impractical and are frequently not complied with.

An experienced attorney will understand and recognize possible DUI defenses and the weaknesses of a urine sample to determine a driver’s blood alcohol level, including pooled urine and why it is necessary for labs to accurately follow a “chain of command.” The differences between a qualified and specialized DUI attorney can make all the difference in an impaired driving case involving urine testing being won or reduced. If you’re wondering how long does alcohol stay in your urine, contact us at 844-832-6384.

Copyright 2015. William C. Head. All Rights Reserved.