Blood-alcohol measurement with

Alcohol. The number of driving under the influence of alcohol (DUl) cases reflects the enormity of the dmnken driving problem in the United States (9). Tests to measure blood alcohol concentration are conducted on blood, urine, or breath (10). In the case of urine and breath, the alcohol concentration measured is reported in terms of the equivalent blood alcohol concentration. Most states in the United States presume that a person is under the influence of alcohol with respect to driving a motor vehicle at a blood alcohol concentration of 0.10%, ie, an ethanol concentration >10 g/100 mL of blood. Some states maintain a lower necessary concentration of 0.08%. In some European countries levels are as low as 0.05%. A blood alcohol concentration of 0.10% in a 68-kg (150-lb) person is the equivalent of about four drinks of 80 proof alcohoHc beverage or four 340-g (12-oz) beers in the body at the time of the test (see Beer Beverage spirits, distilled Wine). Ethanol is metabolized at the equivalent rate of about one drink per hour. 

Beta radiation Electron emission from unstable nuclei, 26,30,528 Binary molecular compound, 41-42,190 Binding energy Energy equivalent of the mass defect measure of nuclear stability, 522,523 Bismuth (m) sulfide, 540 Blassie, Michael, 629 Blind staggers, 574 Blister copper, 539 Blood alcohol concentrations, 43t Body-centered cubic cell (BCC) A cubic unit cell with an atom at each comer and one at the center, 246 Bohrmodd Model of the hydrogen atom... 

Arterial blood was used for the reasons outlined previously, about 500 ml. being obtained from each individual directly into 95% ethyl alcohol. After acidification, filtration, concentration, and further extraction with alcohol and with petroleum ether, a crude extract was obtained. All the various fractions were tested and discarded if inactive, the test animal used being the anesthetized rat. Because the active material may have been present in very small amounts, concentrated crude extracts were injected intravenously while the rat s blood pressure was being continuously measured by an optical manometer, the needle of which was inserted into the femoral artery. Blood extracts from normal individuals were used as controls and the differences compared. 

A more down-to-Earth use of fuel cells is found in traffic-law enforcement. Police officers need quick and simple ways to determine a person s blood alcohol level in the field. In the time it takes to bring a person to the station or to a hospital for a blood or urine test, the person s blood alcohol content (BAG) might change. Fuel cells, such as the one in the device shown above, provide a quick and accurate way to measure BAG from a breath sample. The alcohol ethanol from the person s breath is oxidized to acetic acid at the anode. At the cathode, gaseous oxygen is reduced and combined with hydronium ions (released from the anode) to form water. The reactions generate an electric current. The size of this current is related to the BAG. 

Statutory laws for driving under the influence of alcohol were originally based on the concentration of ethanol in venous whole blood. Because the collection of blood is invasive and requires intervention by medical personnel, the determination of alcohol in expired air has long been the mainstay of evidential alcohol measurements.There is also growing clinical interest m the determination of breath alcohol at the point-of-care. The fundamental principle for use of breath analysis is that alcohol in capillary alveolar blood rapidly equilibrates with alveolar air in a ratio... 

As already stated, the source of biological material is also important either due to its accessibility (i.e., noninvasive nature) or due to the fact that the analytes to be measured are restricted to certain locations. Biomarkers can be detected in all biological entities (i.e., fluids, gases, and tissues), and depending on what is to be measured each biological source has a specific niche. For example the fact that alcohol is excreted in the lung, combined with the convenience of using exhaled air, has been exploited for many years in the breathalyzer test as an indirect measurement of blood alcohol levels [5 ]. Stool is commonly used for the detection of parasites and infections. Tears have been proposed to detect and treat ocular toxicity [6], Urine has also been used extensively to measure both renal and non-renal injuries. However, for the most part, blood (serum or plasma) and urine are the most utilized sources. 

Herberg (1993) reported a study that assessed the effects on safety of combining kava with ethanol. This was a double blind, placebo-controlled randomized trial of 40 healthy volunteers (ten males and ten females in each group), aged between 18 and 60 years (mean=4l years). The aim of the study was to test the adverse effects on seven safety-related performance variables when adult volunteers combine kava with acute intake of ethanol at a blood alcohol concentration of 0.05%. The battery of performance tests measured vigilance, coordination, reaction time, and concentration. One group received the kava extract WS 1490 alone, and the other group received the kava extract... 

The suspect is required to exhale into a solution that wiU react with the unmetabolized alcohol in the breath. The partial pressure of the alcohol in the exhaled air has been demonstrated to be proportional to the blood alcohol level. The solution is an acidic solution of dichromate ion, which is yellow-orange. The alcohol reduces the chromium in the dichromate ion from +6 to +3, the Cr + ion, which is green. The intensity of the green color is measured, and it is proportional to the amount of ethanol that was oxidized. The reaction is ... 

The blood alcohol content of an individual is determined enzymatically by reacting ethanol with NAD" in the presence of the enzyme alcohol dehydrogenase to produce NADH (Table 22.1). The rate of formation of NADH is measured at 340 nm (Figure 22.4). The following absorbances are recorded for a 0.100% (wt/vol) alcohol standard and the unknown, treated in the same way. Use a spreadsheet to calculate the rates of absorbance changes and from these, the unknown concentration. 

One way of testing for tetrachloroethylene exposure is to measure the amount of the chemical in the breath, much the same way breath alcohol measurements are used to determine the amount of alcohol in the blood. This test has been used to measure levels of the chemical in people living in areas where the air is contaminated with tetrachloroethylene or those exposed to the chemical through their work. Because it is stored in the body s fat and is slowly released into the bloodstream, it can be detected in the breath for weeks following a heavy exposure. Tetrachloroethylene can be detected in the blood. Also, breakdown products of the chemical can be detected in the blood and urine of people exposed to tetrachloroethylene. Trichloroacetic acid (TCA), a breakdown product of tetrachloroethylene can be detected for several days after exposure. These tests are relatively simple to perform. The breath, blood, or urine must be collected in special... 

This graph shows that with an assumed specificity of 70%, a sensitivity of 90% is achieved. The estimated BACs based on breath alcohol measurement were validated by blood sample analysis at the end of the trial. 

Clinical samples of urine, blood, expired air, and tissue have been examined using headspace sampling approaches. Thus, chlorinated organic compounds, methanol, acetone, methyl ethyl ketone, and phenols have been determined in urine. Volatile substances in urine have also been used as a guide to acute poisoning, and the determination of stimulants in urine has been proposed as screening test for field use. The determination of the concentration of blood alcohol is the most well-known application of headspace techniques to biological samples. Blood has also been examined for cyanide, methyl sulfide, and formaldehyde levels, the last as a measure of methanol intoxication. The headspace approach for blood samples overcomes the difficulties associated with the alternative direct injection of two-phase samples. 

Alcohols Lower alcohols have been measured with alcohol oxidase (EC 1.1.3.13) from Candida boidinii or Pichia pastoris. The latter is available with a higher specific activity and has a somewhat different substrate specificity. Coimmobilization with catalase increases the stability of the enzyme column to several months with an operating range of 0.005-1 mmol 1 (0.5 ml samples) using 0.1 mol 1 sodium phosphate, pH 7.0, as the buffer. This assay is useful for the determination of ethanol in samples from beverages, blood, and for monitoring fermentation. 

Both tests measure alcohol in the breath.The legal definition of being under the influence of alcohol is based on blood alcohol content, not breath alcohol content. The chemical correlation between these two measurements is that air deep within the lungs is in equilibrium with blood passing through the pulmonary arteries, and an equilibrium is established between blood alcohol and breath alcohol. It has been determined by tests in persons drinking alcohol that 2100 mL of breath contains the same amount of ethanol as 1.00 mL of blood. 

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