Essential DUI Articles
Driver's Impairment Articles
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Absorption and Elimination Rates Articles
Anstie, Final experiments on the elimination of alcohol from the body; 13 Practitioner 15(1874)
Brick, Standardization of Alcohol Calculations in Research, 30 Alcoholism: Clinical and Experimental Research, 1276 (2006)
Dubowski, Absorption, Distribution and Elimination of Alcohol: Highway Safety Aspects, 10 Journal of Studies on Alcohol Supp. 98 (1985)
Key aspects of the pharmacokinetics of alcohol are highly relevant to highway safety. Of particular pertinence are the partition of alcohol between various body tissues and fluids and the resulting alcohol concentration ratios for blood: breath and other body fluids, as well as the irregularity and short-term fluctuations of the blood and breath alcohol curves. Most alcohol pharmacokinetics parameters are subject to wide intersubject variability, as exemplified by peak blood alcohol concentrations reached on ingestion of identical weight-adjusted doses, time to peak after end of drinking and the rate of alcohol elimination from the blood. This great biological intersubject variability, when combined with sex-, age- and time-related differences, makes the blood alcohol information in widely distributed alcohol consumption nomograms and tables based on mean data inappropriate as a guide for the drinking behavior of individuals. Although there is good statistical correlation between the alcohol concentration of different body tissues and fluids in the fully postabsorptive state, wide individual variations from the population mean alcohol partition values exist. It is often impossible to determine whether the postabsorptive state has been reached at any given time. Those factors make it impossible or infeasible to convert the alcohol concentration of breath or urine to the simultaneous blood alcohol concentration with forensically acceptable certainty, especially under per se or absolute alcohol concentration laws. Inclusion of breath alcohol concentrations in drinking-driving statutes, as definitions or per se offense elements, makes unnecessary the conversion of breath alcohol analysis results into equivalent blood alcohol concentrations. Urine alcohol concentrations are inadequately correlated with blood alcohol concentrations or with driver impairment, and analysis of bladder urine is, therefore, inappropriate in traffic law enforcement. Significantly large sex-related differences in pharmacokinetic parameters have been demonstrated (e.g., in peak blood alcohol concentrations for weight-adjusted doses). The effects of age and time of day have been less extensively studies and are less clear. Breath and blood alcohol time curves are subject to short-term fluctuations from the trend line and other irregularities, and often do not follow the typical Widmark pattern. From the existing information on pharmacokinetics of alcohol and the characteristics and variability of blood and breath alcohol versus time curves, the following conclusions can be reached.(ABSTRACT TRUNCATED AT 400 WORDS)
Abstract courtesy of www.pubmed.org – A service of the National Library of Medicine and the National Institutes of Health
Jeavons, Zeiner; Effects of Elevated Female Sex Steroids on Ethanol and Acetaldehyde Metabolism in Humans; 8 Alcoholism: Clinical and Experimental Research 352 (1984)
Two groups (n = 20 each for pill and no pill groups) of young female social drinkers were tested with an acute ethanol dose (0.52 g/kg) as a 20% solution in water. Ethanol pharmacokinetics and acetaldehyde were repeatedly assayed from breath by a gas chromatograph. Cardiovascular indices were concurrently recorded. Groups did not differ on ethanol pharmacokinetics. However, the group on birth control pills reached a significantly higher acetaldehyde concentration than did the group of normally cycling females not on birth control pills (3.26 ng/ml vs. 1.45 ng/ml). Further, the pill (P) group showed significantly greater vasodilation 20 min postdrink as indexed by ear lobe plethysmopraphy than did the no pill (NP) group (P = 160.3% vs. NP = 113.9%). Results are consistent with the interpretation that female sex steroids modulate aldehyde dehydrogenase function. Practical implications are that females with elevated steroids (either pregnant or on birth control pills) may be at grater risk for toxic effects of ethanol consumption.
Jones, Concentration-Time Profiles of Ethanol in Capillary Blood after Ingestion of Beer, 31 Journal of Forensic Science Society 429 (1991)
Blood ethanol profiles were determined in experiments with healthy volunteers after they had drunk beer. When 330 ml of light beer (1.8% w/v ethanol) was consumed in 5 min by four men and four women, the average peak blood-alcohol concentration (BAC) reached was 8 mg/100 ml (range 2-11). After nine men had drunk 660 ml of beer (3.0% w/v or 3.6% w/v ethanol) in 25 minutes on an empty stomach, the average peak BAC was 32 mg/100 ml (range 26-44) and 37 mg/100 ml (range 23-54) respectively. When the same two beers were consumed by another nine men together with a meal, the peak BAC was 24 mg/100 ml (range 20-29) and 28 mg/100 ml (range 20-39) respectively. The peak BAC occurred earlier when beer was ingested together with food; mean 32 min (range 30-50) compared with 41 min (range 30-70) with an empty stomach. The rate of disappearance of alcohol from blood (beta-slope) was 12 mg/100 ml/h in the fed state and 15 mg/100 ml/h when subjects were fasted. The apparent volume of distribution of ethanol (Vd) was 0.65 l/kg (SD 0.07) for the empty stomach condition but exceeded unity when beer was ingested together with food. It seems that part of the dose of alcohol when consumed with food never reaches the systemic circulation.
Abstract courtesy of www.pubmed.org – A service of the National Library of Medicine and the National Institutes of Health
Kevin’s summary: Food traps some of the Alcohol= lower peak BAC (trapped Al.) slower elim. faster peak (untrapped Al.)
Jones, Jonsson, Between-subject and within-subject variations in the pharmacokinetics of ethanol, Br J clin Pharmac 37: 427-431 (1994)
1. Twelve healthy men drank 0.80 g ethanol kg-1 body weight on four occasions spread over several weeks. Ethanol was given as 96% v/v solvent which was diluted with orange juice to make a cocktail (20-25% v/v). This drink was ingested in exactly 30 min at 08.00 h after an overnight (10 h) fast. 2. Samples of venous blood were obtained at exactly timed intervals of 0, 10, 20, 30, 45, 60, 90, 120, 150, 180, 240, 300, and 360 min after the start of drinking. The concentrations of ethanol in whole blood were determined by headspace gas chromatography. 3. Summary measures were used to evaluate the concentration-time profiles of ethanol for each subject. The between-subject and within-subject components of variation for the pharmacokinetics of ethanol were derived by one-way analysis of variance (ANOVA). 4. The variation between different subjects dominated the total variance for all of the pharmacokinetic parameters studied except the rate of disappearance of ethanol from blood (ko). For this latter parameter, 42% and 58% of the total variation arose from variations between- and within-subjects respectively. These results might be important to consider when experiments on the clinical pharmacokinetics of ethanol are being planned.
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Jones, Disappearance Rate of Ethanol from the Blood of Human Subjects: Implications in Forensic Toxicology 38(1) Journal of Forensic Sciences 103 (1993)
This article outlines major developments in knowledge about the human metabolism of ethanol. The results of a large number of controlled experiments aimed at measuring the rate of ethanol elimination from the blood are reported. The factors that influence the rate of ethanol elimination from blood, such as the amount of ethanol ingested, the drinking habits of the subjects, and the effect of food taken together with, or before, drinking were investigated. The slowest rate of ethanol disappearance was observed in a healthy male subject who ingested 0.68 g ethanol/kg body weight after an overnight (8 h) fast; the beta-slope was 9 mg/dL/h. The fastest rate of ethanol disappearance was observed in a male chronic alcoholic during detoxification; the beta-slope was 36 mg/dL/h. This four-fold difference in the rate of ethanol disposal should be considered when the pharmacokinetics of ethanol become an issue in drinking and driving trials, for example, when retrograde estimations are attempted.
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Jones et al., Peak Blood-Ethanol Concentration and the Time of Its Occurrence After Rapid Drinking on an Empty Stomach, 36 (2) Journal of Forensic Sciences, 376 (1991)
Healthy men, 20 to 60 years old, drank a moderate dose of ethanol in the morning after an overnight fast. They consumed either neat whisky in amounts corresponding to 0.34, 0.51, 0.68, 0.85, or 1.02 g of ethanol per kilogram of body weight or 0.80 g/kg ethanol solvent diluted with orange juice. The peak blood-ethanol concentration (BEC) increased with the dose administered, but the time required to reach the peak was not markedly influenced over the range of doses studied. At a dose of 0.68 g/kg, the peak BEC ranged from 52 to 136 mg/dL (N = 83), and slow absorption (a late-occurring peak) produced a lower peak BEC. The peak BEC was reached between 0 and 45 min for 77% of the subjects (N = 152) and between 0 and 75 min for 97% of them. The time of peaking in venous blood occurred, on average, 10 min later than in capillary (fingertip) blood although the peak BEC was not appreciably different; the mean venous BEC was 97.0 mg/dL (range, 76 to 112 mg/dL), and the mean capillary BEC was 99.6 mg/dL (range, 75 to 123 mg/dL). When subjects drank 0.80 g/kg ethanol diluted with orange juice over 30 min, the average BEC increment between the end of drinking and the peak was 33 mg/dL (range, 0 to 58 mg/dL). The rate of absorption of ethanol was 1.78 mg/dL/min (range, 0.52 to 4.8 mg/dL/min), and the peak BEC occurred within 60 min after the end of drinking in 92% of the trials. The largest BEC increment (mean, 21 mg/dL; range, 0 to 44 mg/dL) was seen during the first 15 min after the drinking period.
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Blood Testing Articles
Anderson, Collection and Storage of Specimens for Alcohol Analysis, Medical-Legal Aspects of Alcohol 237, 239 (James C. Garriott ed., 4th ed. 2003)
Kevin’s summary: Author summarized studies saying refrigeration and 2% Sodium Fluoride is required instead of 1%. Study blames an automatic pipetting device for the anti law enforcement results.
Blackmore, The Bacterial Production of Ethyl Alcohol, 8 Forensic Science Society Journal (1968)
The production of ethyl alcohol by a variety of bacteria from laboratory media and human tissue homogenates has been studied. Most bacteria commonly found at post-mortem can produce a significant amount of ethyl alcohol form glucose, sucrose, mannite or lactose. The same bacteria produced less than 20mg/100ml from ornithine, lysine, arginine and urea. Ethyl alcohol production can occur from tissue with gllucose concentrations of less than 20mg/ml. No ethyl alcohol was produced from carbohydrate and protein-fee urine. Sodium fluoride at a concentration of not less than 1% was needed to maintain sterility of stored blood. An analytical sequence is suggested for the determination of ethyl alcohol in samples taken at post-mortem in the effect of bacterial contamination is to be minimised.
Kevin’s summary: Sodium Fluoride at not less than 1% is required to maintain sterility of stored blood
Blume & Lakatura, The Effect of Microbial Contamination of the Blood Sample on the Determination of Ethanol Levels in Serum, 60 Am. J. Clin. Path. 700, 701 (Nov. 1973)
Kevin’s summary: Sodium Fluoride is ineffective
Chang and Kollman, The Effect of Temperature on the Formation of Ethanol by Candida Albicans in Blood, 34(1) Journal of Forensic Sciences, 105-109(1989)
The effect of temperature on microbial fermentation in blood was studied. Specimens of human blood from a blood bank were inoculated with Candida albicans, an organism capable of causing fermentation. A preservative was added to a portion of the inoculated specimens. These inoculated specimens, as well as uninoculated blood, were stored under various temperature conditions. Production of ethyl alcohol was monitored over a period of six months. Fermentation was found to be highly temperature dependent, with refrigeration proving to be most effective at inhibiting ethanol formation.
Abstract courtesy of www.pubmed.org – A service of the National Library of Medicine and the National Institutes of Health
Kevin’s summary: Sodium Fluoride is ineffective against the most common and dangerous pathogen of humans; Candida Albicans
Dubowski and Essary, Contamination of Blood Specimens for Alcohol Analysis During Collection, 4 Abstracts and Reviews in Alcohol and Driving, 3 (1983)
Fornabai, Demystifying the Gas Chromatograph (2001)
Glover, The Effect of Heat on Blood Samples Containing Alcohol, Forensic Tests for Alcohol Branch, North Carolina Department of Health and Human Services
In a pilot study the effect of heat on blood samples with and without alcohol present was examined. Blood drawn from donors was exposed to temperatures that ranged from 17 degrees C to 46.8 degrees C over a 78-day period. Temperatures were recorded every 5 minutes for the first 30 days. Tubes were retrieved periodically and the alcohol concentration was determined. The starting alcohol concentrations ranged from 0.062 gm/100ml to 0.123 gm/100ml. An average decrease in the alcohol concentration of 0.018 gm/100ml was observed to occur during the initial 3 days of exposure. After the initial decrease there was minimal decrease. No alcohol was detected in any of the samples that were taken from alcohol free donors. Samples exposed to rather harsh conditions, i.e. high heat, will not cause an elevated alcohol concentration. The loss of alcohol during the first 3 days while unrefrigerated suggests that it would be prudent to refrigerate samples whenever possible.
Jones & Neri, Evaluation of Blood-Ethanol Profiles After Consumption of Alcohol Together with a Large Meal, 24(3) Canadian Society of Forensic Science Journal 165 (1991)
Jones, Hylen, Svensson & Helander, Storage of Specimens at +4°C or Addition of Sodium Fluoride (1%) Prevents Formation of Ethanol in Urine Inoculated with Candida Albicans, 23 Journal of Analytical Toxicology 333 (1999)
Department of Forensic Toxicology, University Hospital, Linkoping, Sweden.
The microbial synthesis of ethanol was investigated in urine specimens containing 0.5% or 1.0% (w/v) glucose and inoculated with the yeast Candida albicans (100 cfu/mL). Aliquots (10 mL) of urine were dispensed into plastic tubes containing enough sodium fluoride to give final concentrations of 0.1%, 0.25%, 0.5%, 0.75%, 1%, and 2% (w/v), and C. albicans was added. The tubes were tightly stoppered and allowed to stand either at room temperature (22 degrees C) or in a refrigerator (4 degrees C) for up to 34 days before concentrations of ethanol were determined by headspace gas chromatography. Urine samples stored at 22 degrees C without sodium fluoride produced 0.25 g/L ethanol after two days, and the concentration increased to 2.10 g/L and 4.50 g/L after eight days for specimens containing 0.5% (w/v) and 1% (w/v) glucose, respectively. The ratio of the serotonin metabolites 5-hydroxytryptophol/5-hydroxyindoleacetic acid (5HTOL/5HIAA) in urine remained within the reference range (< 15 pmol/nmol) despite high concentrations of ethanol being produced. Urine samples kept at 4 degrees C did not produce any ethanol (< 0.01 g/L) even without sodium fluoride present as a preservative. The production of ethanol by C. albicans was stopped completely by adding 1% or 2% (w/v) sodium fluoride but not by concentrations of 0.75% (w/v) or less. The microbial synthesis of ethanol in urine samples initially stored at room temperature without sodium fluoride was slowed down considerably by moving them into a refrigerator at 4 degrees C. In conclusion, the production of ethanol in urine by C. albicans can be prevented by storage of samples in a refrigerator at 4 degrees C or by adding sodium fluoride > or = 1% (w/v). Measuring the ratio of 5HTOL/5HIAA can help to distinguish postsampling production of ethanol from metabolism and excretion processes.
Abstract courtesy of www.pubmed.org – A service of the National Library of Medicine and the National Institutes of Health
Kaye, The Collection and Handling of the Blood Alcohol Specimen, 74 American Society of Clinical Pathologists 743 (1980)
Proper collection, handling, and storage of the blood alcohol specimen are essential in medicolegal cases involving the question of sobriety. A standard operating procedure is necessary to ensure maximum reliability. Comments are offered on the advantages of using blood specimens in preference to urine or tissue specimens. The use of a conversion factor to obtain a calculated "presumed blood level" can be dangerous. Cautions and suggestions are offered regarding how and from where the blood should be obtained from a living person and during an autopsy. There are certain time limitations for storage of these blood-alcohol specimens. Each laboratory must establish its own limits for reliable storage, given the conditions in that laboratory. Unexpected and confusing results can lead to an erroneous interpretation if history, circumstances, type of injury, and survival time are not all carefully considered. Several possibilities for error in judgment are discussed.
Abstract courtesy of www.pubmed.org – A service of the National Library of Medicine and the National Institutes of Health
Kevin’ summary: 1% or less of sodium fluoride allows for only two days storage.
Labianca, Conversion of Serum-Alcohol Concentrations to Corresponding Blood-Alcohol Concentration, 79 J. Chem. Educ. 803 (2002)
Martin, Moll, Schmid, Dettli, The Pharmacokinetics of Alcohol in Human Breath, Venous and Arterial Blood After Oral Ingestion, 26 European Journal of Clinical Pharmacology 619 (1984)
The concentration-time profile of ethanol in breath air (AAC), arterial (ABAC) and venous blood (VBAC) of human volunteers was studied after four different oral doses of absolute alcohol--0.5, 0.75, 1.0, and 1.25 g/kg body weight. Seventy-eight single dose experiments were carried out in 42 subjects. In all 78 studies AAC was measured and VBAC was estimated simultaneously in blood collected from a cubital vein of 36 volunteers. Arterial blood, too, was collected from 8 subjects from a catheter in a brachial artery. All blood alcohol concentrations were analysed independently by gas chromatography (GLC) and an enzymatic (ADH) method. A one-compartment open model with first order absorption and pseudo-zero-order elimination was employed to calculate the pharmacokinetic parameters. The average values for the first order absorption rate constant (ka) ranged from 2.2 to 3.1, from 2.4 to 2.6 and from 1.0 to 1.7 h-1 for ACC, ABAC and VBAC, respectively. The pseudo-zero-order elimination rate constant (beta) was 0.17 to 0.18, 0.21 to 0.22 and 0.26 to 0.27 g X 1(-1) X h-1, respectively. During absorption ABAC tended to be higher than VBAC, peaking at a higher level (Cmax) and with a shorter time to peak (tmax) until an arterio-venous concentration equilibrium was reached, whereafter VBAC remained above ABAC. Although there was a close relationship between AAC, ABAC and VBAC during elimination, AAC closely followed the pattern of ABAC during absorption and tended to deviate from VBAC. AAC, therefore, is a much better predictor of ABAC during absorption than VBAC.
Abstract courtesy of www.pubmed.org – A service of the National Library of Medicine and the National Institutes of Health
Plueckhahan and Ballard, Factors Influencing the Significance of Alcohol Concentrations in Autopsy Blood Samples, The Medical Journal of Australia (1968)
Kevin’s summary: 1% sodium Fluoride = only preservative and strength effective
Watts & McDonald, The Effect of Biologic Specimen Type of the Gas Chromatographic Headspace Analysis of Ethanol and Other Volatile Compounds American Journal of Clinical Pathology 1987; 87: 79-85
Gas chromatographic analyses of 37 degrees C headspace vapors above liquid phases saturated with sodium chloride demonstrated that the partitioning of isopropanol, n-propanol, and t-butanol from blood, plasma, or serum to headspace vapor was greatly reduced relative to that observed with the use of water as the liquid phase. The partitioning of ethanol and acetone was moderately reduced with these specimens relative to water, while no effect was seen with methanol or acetonitrile. Normal urine only slightly affected relative partitioning, and vitreous humor had no effect. The partitioning reductions observed with blood were not affected by changing the equilibration temperature to 25 degrees C, by lengthening the equilibration time to three days, nor by changing the concentration of the volatiles in the liquid phase. The use of saturated sodium sulfate enhanced the differences in partitioning observed between water and blood. Only with substantial dilution (5:1) of blood specimens was the effect abolished.
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Winek, Paul; Effect of Short-Term Storage Conditions on Alcohol Concentration in Blood from Living Human Subjects, 29 Clinical Chemistry 1959 (1983)
We examined the effects of time, temperature, and a preservative (sodium fluoride) on ethanol concentrations in stored samples of whole blood from living human subjects. We measured the ethanol in the first, second, seventh, and 14th day of storage, by gas chromatography. Samples were stored at 0-3°C and at 22-29°C, with and without preservative. None of these showed significant gains or losses in concentration. The average differences between ethanol as measured on the day of collection and after storage were all within the range of experimental error of the method (±5%)
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Breathtesting Articles
BAC General Accuracy
Anderson and Hlastala, The Kinetics of Transdermal Ethanol Exchange, 100 J Appl Physiol. 649 (2006)
The kinetics of ethanol transport from the blood to the skin surface are incompletely understood. We present a mathematical model to predict the transient exchange of ethanol across the skin while it is being absorbed from the gut and eliminated from the body. He model simulates the behavior of a commercial device that is used to estimate the blood alcohol concentration (BAC). During the elimination phase, the stratum corneum of the skin has a higher ethanol concentration that the blood. We studied the effect of varying the maximum BAC and the absorption rate from the gut on the relationship between BAC and equivalent concentration in the gas phase above the skin. The results showed that the ethanol concentration in the gas compartment always took longer to reach its maximum, had a lower maximum, and had a slower apparent elimination rate than the BAC. These effects increased as the maximum BAC increased. Our model’s predictions are consistent with experimental data from the literature. We performed a sensitivity analysis (using Latin hypercube sampling) to identify and rank the importance of parameters. The analysis showed that outputs were sensitive to solubility and diffusivity within the stratum corneum, to stratum corneum thickness, and to the colume of gas in the sampling chamber above the skin. We conclude that ethanol transport through the skin is primarily governed by the washing and washout of ethanol through the stratum corneum. The dynamics can be highly variable from subject because of variability in the physical properties of the stratum corneum.
Bell and Flack, Examining Variables Associated with Sampling for Breath Alcohol Analysis, Victoria Forensic Science Centre
The effects on BAC reading caused by differences in volume of sample delivered, exhaled breath temperature, and alteration of breathing style just prior to delivery, were studied. The variables of BAC, volume, temperature and pressure were measured over the delivery of a breath sample at a rate of 4 times per second in 14 drinking human subjects using 2 specially modified Dräger Alcotest 7110 breath alcohol analyzers. BAC readings at 0.5 and 1.0 L delivery volumes were, on average, 80±4 and 93±2% of the 1.5 L BAC reading respectively. Also, the BAC readings at 0.5, 1.0 and 1.5 L delivery volume were, on average, 76±8, 86±5 and 91±5% of the final BAC reading respectively. A trend of lower percentage of final BAC values with increasing lung vital capacity was observed. Hyperventilation and breath holding for ca. 10 seconds just prior to sample delivery respectively decreased and increased the breath temperature, BAC and percentage of final BAC callused. Standardization of the results of breath analyses to 34.0°C resulted in smoother blood alcohol decay profiles, including the test involving hyperventilation of breath holding. The correlation between simultaneous blood and breath analyses (n+31) was, on the whole, improved by standardization of the breath analysis result to 34.0°C. The differences (breath – blood) between simultaneous blood and breath analyses were, on average, -0.0085 ±0.0070 and -0.0136±0.0074 g/100 mL and the calculated blood/breath partition ratio values were 2509 ±150 and 2336±172 for corrected and uncorrected data respectively. The cooling effect of the mouthpiece on the breath sample was measured as 1.0°C, using both breath from a human subject and simulated breath samples.
Dubowski & Essary, Measurement of Low Breath-Alcohol Concentrations: Laboratory Studies and Field Experience, 23 Journal of Analytical Toxicology 386, 394 (October 1999)
Recent federal rules and traffic law changes impose breath-alcohol thresholds of 0.02 and 0.04 g/210 L upon some classes of motor vehicle operators, such as juveniles and commercial vehicle operators. In federally regulated alcohol testing in the workplace, removal of covered workers from safety-sensitive duties, and other adverse actions, also occur at breath-alcohol concentrations (BrACs) of 0.02 and 0.04 g/210 L. We therefore studied performance of vapor-alcohol and breath-alcohol measurement at low alcohol concentrations in the laboratory and in the field, with current-generation evidential analyzers. We report here chiefly our field experience with evidential breath-alcohol testing of drinking drivers on paired breath samples using 62 Intoxilyzer 5000-D analyzers, for BrACs of 0-0.059 g/210 L. The data from 62 law enforcement breath-alcohol testing sites were collected and pooled, with BrACs recorded to three decimal places, and otherwise carried out under the standard Oklahoma evidential breath-alcohol testing protocol. For 2105 pooled simulator control tests at 0.06-0.13 g/210 L the mean +/- SD of the differences between target and result were -0.001 +/- 0.0035 g/210 L and 0.003 +/- 0.0023 g/210 L for signed and absolute differences, respectively (spans -0.016-0.010, 0.000-0.016). For 2078 paired duplicate breath-alcohol measurements with the Intoxilyzer 5000-D, the mean +/- SD difference (BrAC1-BrAC2) were 0.002 +/- 0.0026 (span 0-0.020 g/210 L). Variability of breath-alcohol measurements was related inversely to the alcohol concentration. Ninety-nine percent prediction limits for paired BrAC measurements correspond to a 0.020 g/210 L maximum absolute difference, meeting the NSC/CAOD recommendation that paired breath-alcohol analysis results within 0.02 g/210 L shall be deemed to be in acceptable agreement. We conclude that the field system for breath-alcohol analysis studied by us can and does perform reliably and accurately at low BrACs.
Abstract courtesy of www.pubmed.org – A service of the National Library of Medicine and the National Institutes of Health
Dubowski, Quality Assurance in Breath-Alcohol Analysis, 18 Journal of Analytical Toxicology 306 (Oct 1994)
Evidential breath-alcohol testing requires an adequate quality assurance (QA) program to safeguard the testing process and validate its results. A comprehensive QA program covers (a) test subject preparation and participation; (b) the analysis process; (c) test result reporting and records; (d) proficiency testing, inspections, and evaluations; and (e) facilities and personnel aspects. Particularly important are the following necessary scientific safeguards as components of quality control: (a) a pretest deprivation-observation period of at least 15 minutes; (b) blank tests immediately preceding each breath-collection step; (c) analysis of at least duplicate breath specimens; and (d) a control test accompanying every subject test. These safeguards have withstood adversarial challenges in the judicial system for more than 30 years.
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Gulberg, Distribution of the Third Digit in Breath Alcohol Analysis, 36 Journal of Forensic Science 976 (1991)
Harding, Field, Breathalyzer Accuracy in Actual Law Enforcement Practice: A Comparison of Blood-and Breath-Alcohol Results in Wisconsin Drivers, 32 Journal of Forensic Science 1235 (1987)
Breathalyzer and blood-alcohol results from drivers arrested for operating a motor vehicle while intoxicated and for related offenses were compared during a two-year period. Four hundred and four pairs of breath- and blood-alcohol results from specimens collected within 1 h of each other were studied. Blood-alcohol concentrations ranged from zero to 0.421% weight per volume (w/v). Breath-alcohol concentrations ranged from zero to 0.44 g/210 L. The mean Breathalyzer result was 0.16 g/210 L. The mean blood-alcohol result was 0.176% w/v. Compared to the blood-alcohol result, Breathalyzer results were lower by more than 0.01 g/210 L 61% of the time, within 0.01 g/210 L 33% of the time, and higher by more than 0.01 g/210 L 6% of the time.
Abstract courtesy of www.pubmed.org – A service of the National Library of Medicine and the National Institutes of Health
Kevin’s summary: Only 33% of breathtests correlated to associated blood tests. But watch out because breath is more often lower than blood.
Harding, Methods for Breath Analysis, Medical-Legal Aspects of Alcohol 185, 186 (James C. Garriott ed.,)
Hlastala, Breathing-Related Limitations to the Alcohol Breath Test. DWI Journal: Science and Law 17: 1-4, (December, 2002)
Hlastala, Invited Editorial on “The Alcohol Breath Test,” 93 Journal of Applied Physiology 405, 405 (2002)
Hlastala, Physiological Errors Associated with Alcohol Breath Testing, 9 The Champion 16 (1985)
Hlastala, Physiological Laws of Alcohol Breath Testing
The design of current breath alcohol testers lead to several potential errors owing to normal physiological factors. Breath testing for blood alcohol concentration originated over thirty years ago. At that time Understanding of the physiology of the lung was quite primitive. As a result testing procedures contain implicit errors. There are four major sources of error: (1) variability in the normal measured blood-breath alcohol partition ratio which may lead to a potential error of ±30% but individual cases can have even greater error: (2) variability in breathing patter, because of the interaction of alcohol with the airway surface, can cause an error of as much as ± 50%; (3) variation in normal body temperature can cause an error of ±6% and: (4) variation in normal blood hemotocrit can cause and error of ±14%. There errors alone add up to a very high random variability. Since the errors are caused by the normal physiology of the body and are external to the breath testing instrument, every breath tester currently used is subject to large potential error when used to estimate blood alcohol concentration.
Hlastala, The Alcohol Breath Test – A Paradigm Shift
Hlastala, The Alcohol Breath Test – A Review, 84 (2) Journal of Applied Physiology 401, 402-03 (1998)
The alcohol breath test (ABT) is evaluated for variability in response to changes in physiological parameters. The ABT was originally developed in the 1950s, at a time when understanding of pulmonary physiology was quite limited. Over the past decade, physiological studies have shown that alcohol is exchanged entirely within the conducting airways via diffusion from the bronchial circulation. This is in sharp contrast to the old idea that alcohol exchanges in the alveoli in a manner similar to the lower solubility respiratory gases (O2 and CO2). The airway alcohol exchange process is diffusion (airway tissue) and perfusion (bronchial circulation) limited. The dynamics of airway alcohol exchange results in a positively sloped exhaled alveolar plateau that contributes to considerable breathing pattern-dependent variation in measured breath alcohol concentration measurements.
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Hlastala, Anderson; The Impact of Breathing Pattern and Lung Size on the Alcohol Breath Test; Annals of Biomedical Engineering (2006)
Highly soluble gases exchange primarily with the bronchial circulation through pulmonary airway tissue. Because of this airway exchange, the assumption that end-exhaled alcohol concentration (EEAC) is equal to alveolar alcohol concentration (AAC) cannot be true. During exhalation, breath alcohol concentration (BrAC) decreases due to uptake of ethanol by the airway tissue. It is therefore impossible to deliver alveolar gas to the mouth during a single exhalation without losing alcohol to the airway mucosa. A consequence of airway alcohol exchange is the EEAC is always less than AAC. In this study, we use a mathematical model of the human lung to determine the influence of subject lung size on the relative reduction of BrAC from AAC. We find that failure to inspire a full inspiration reduces the BrAC at full exhalation, but increases the BrAC at minimum exhalation. In addition, a reduced inhaled volume and can lead to an inability to provide an adequate breath volume. We conclude that alcohol exchange with the airways during the single exhalation breath test is dependent on lung size of the subject with a bias against subjects with smaller lung size.
Hlastala, Why Breath Tests of Blood-Alcohol Don’t Work, In: DWI on Trial – The Big Apple Seminar. May, 2001.
Johnson, Horowitz, Maddox, Wishart, Shearman, Cigarette Smoking and Rate of Gastric Emptying: Effect on Alcohol Absorption, 302 British Medical Journal 20 (1991)
OBJECTIVE--To examine the effects of cigarette smoking on alcohol absorption and gastric emptying. DESIGN--Randomised crossover study. SETTING--Research project in departments of medicine and nuclear medicine. SUBJECTS--Eight healthy volunteers aged 19-43 who regularly smoked 20-35 cigarettes a day and drank small amounts of alcohol on social occasions. INTERVENTIONS--Subjects drank 400 ml of a radiolabelled nutrient test meal containing alcohol (0.5 g/kg), then had their rates of gastric emptying measured. Test were carried out (a) with the subjects smoking four cigarettes an hour and (b) with the subjects not smoking, having abstained for seven days or more. The order of the tests was randomised and the tests were conducted two weeks apart. MAIN OUTCOME MEASURES--Peak blood alcohol concentrations, absorption of alcohol at 30 minutes, amount of test meal emptied from the stomach at 30 minutes, and times taken for 50% of the meal to leave the proximal stomach and total stomach. RESULTS--Smoking was associated with reductions in (a) peak blood alcohol concentrations (median values in non-smoking versus smoking periods 13.5 (range 8.7-22.6) mmol/l v 11.1 (4.3-13.5) mmol/l), (b) area under the blood alcohol concentration-time curve at 30 minutes (264 x 10(3) (0-509 x 10(3)) mmol/l/min v 140 x 10(3)) (0-217 x 10(3) mmol/l/min), and (c) amount of test meal emptied from the stomach at 30 minutes (39% (5-86%) v 23% (0-35%)). In addition, smoking slowed both the 50% gastric emptying time (37 (9-83) minutes v 56 (40-280) minutes) and the intragastric distribution of the meal. There was a close correlation between the amount of test meal emptied from the stomach at 30 minutes and the area under the blood alcohol concentration-time curve at 30 minutes (r = 0.91; p less than 0.0001). CONCLUSION--Cigarette smoking slows gastric emptying and as a consequence delays alcohol absorption.
Abstract courtesy of www.pubmed.org – A service of the National Library of Medicine and the National Institutes of Health
Kevin’s summary: Smoking slows gastric emptying which lowers peak BAC
Jones, Logan, DUI Defenses, Drug Abuse Handbook 1006, 1024 (Steven B. Karch ed., 1988)
Jones, Evaluation of Breath-Alcohol Instruments, 28 Forensic Science International 147 (1985)
This paper reports results from a field trial with a breath-alcohol screening device--Alcolmeter pocket model. Breath tests were made with drivers apprehended during routine controls (road-blocks), for traffic violations and those involved in traffic accidents. Of 908 roadside breath tests made with chemical reagent tubes, 343 showed zero alcohol (no colour change) and these results were confirmed by Alcolmeter. Alcohol was detected in 191 tests but the level was judged as being below the legal limit of 0.50 mg/ml. The Alcolmeter results, however, ranged from 0 to 1.22 mg/ml (mean 0.21 mg/ml) and 15 individuals (7.8%) were above the legal limit. There were 373 positive chemical tube breath screening tests whereas in 5 cases (1.3%) Alcolmeter indicated a blood-alcohol level below 0.50 mg/ml. Duplicate determinations with the Alcolmeter device were highly correlated r = 0.93 +/- 0.02 (+/- S.E.), P less than 0.001. The standard deviation of a single breath-alcohol analysis under field conditions was +/- 0.10 mg/ml which corresponds to a coefficient of variation of 10%. The time interval between positive roadside breath test and blood-sampling ranged from 5 to 220 min (median 62 min). The results were therefore adjusted by 0.15 mg/ml per hour to compensate for ethanol metabolised between the time of sampling blood and breath. The corrected blood and breath values were well correlated r = 0.84 +/- 0.03, P less than 0.001 but the predictive power of the regression relationship was poor. The regression equation was y = 0.27 +/- 0.65x and the standard error estimate was +/- 0.21 mg/ml at the mean concentration of ethanol of 1.0 mg/ml.
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Jones, How Breathing Technique Can Influence the Results of Breath-Alcohol Analysis, 22 (4) Medicine, Science, and the Law 275, 275 (1982)
This paper reports experiments to test how a person’s breathing technique can influence the concentration of ethanol and the temperature of end-expired breath samples. The experiments were performed with healthy men after they drank a moderate dose of ethanol and the concentration of ethanol in breath was determined by gas chromatography. The results were compared with control breaths, which were deep inspirations and forced expirations of room air, analyses within 2-3 minutes of the test-breath sample. With breath-holding (30 seconds) before expiration, the concentration of ethanol increased by 15-7±2-24 percent (mean = SE) and the temperature of breath rose by 0-6 ±0-09°C. Hyperventilating for 20 seconds, immediately before the analysis of breath, decreased the concentrations of ethanol by 10-6 ±1-37 per cent and the breath temperature dropped by 1-0 ±0-22°C. Keeping the mouth closed for 5 minutes (shallow breathing) increased expired ethanol concentration by 7-3 ±1-2 per cent and the breath temperature rose by 0-7 ± 0-4°C. After a slow (20 second) exhalation expired ethanol increased by 2-0± 0-71 per cent but breath temperatures remained unchanged from control tests. My results suggest that the changed in expired ethanol concentrations are partly caused by the rise or fall in the temperature of breath. But an equally important factor is the amount of time the breath spends in contact with the mucous membranes of the upper respiratory tract. A long contact time increases the concentration of ethanol and rapid ventilation lowers it. Regardless of the breathing technique tested the results recovered to control values immediately the subjects began breathing normally again.
Kevin’s summary: Holding breath for 30 seconds = 15.7% increase. Hyperventilating for 20 seconds; decreased by 10.6%
Mouth closed and shallow – nasal breathing for 5 minutes = increase by 7.3%.
Slow 20 second exhale = 2% increase.
Factors = increased temperature of breath
Increased contact with mucous membranes
(also see Ohlson (1990))
Jones, Measuring Alcohol in Blood and Breath for Forensic Purposes – A Historical Review, 8 Forensic Science Review, 13 (1996)
This review concerns important events and trends in the evolution of chemical tests for alcohol intoxication on two continents: Europe and North America. In particular, the pioneer workers in this field and their major contributions to forensic alcohol analysis are emphasized. Quantitative methods for the determination of alcohol in blood, breath, and urine appeared early in the twentieth century and experimental alcohol research had already started in several European countries. The first statutory limits of blood-alcohol concentration (BAC) were introduced in Norway and Sweden during the 1930-1940s where Widmark’s micro-diffusion method was approved for forensic purposed. Between 1931-1935 in the US, the first instrument (the Drunkometer) was developed for measuring the concentration of alcohol in a person’s breath to supplement various clinical signs and symptoms of drunkenness. The breath-alcohol concentration (BrAC) was always translated into the presumed coexisting BAC to furnish corroborative or presumptive evidence of impairment at the wheel. After the Breathalyzer device was developed by Borkenstein around 1953-54, breath-alcohol testing became firmly established for law enforcement purposes in the US and Canada. The classic wet-chemistry methods of blood-alcohol analysis were displaced by enzymatic procedures in the early 1950s and in the 1960s gas chromatographic (GC) methods dominated. Today, headspace GC is the mainstay in forensic science laboratories for the determination of alcohol and other volatile substances in body fluids. The first breath-alcohol devices used in Europe were relatively simple screening tests for alcohol at the roadside and positive results were always followed-up by quantative analysis of alcohol in blood or urine. The technology of breath-alcohol testing has changed dramatically over the years from chemical oxidation and colorimetric procedures towards physicochemical techniques such as gas chromatography, electrochemical oxidation, and multiple wavelength infrared spectrophotometry. In the early 1980s evidential breath-alcohol instruments were approved for law enforcement purposes in many European countries and threshold limits of BrAC were introduced alongside the existing statutory BAC limits.
Jones, Physiological Aspects of Breath-Alcohol Measurement, 6 Alcohol, Drugs and Driving, 2
This paper gives review and opinion about several aspects of quantitative evidential breath alcohol analysis used in traffic law enforcement. In particular, physiological aspects of breath testing are covered, with emphasis on factors influencing the precision and accuracy of results. The increasing use of punishable limits of blood and/or breath-alcohol concentration makes chemical test evidence a popular target for defense attack and litigation in trials concerned with driving under the influence (DUI). Historical developments in theory and application of breath testing as evidence of intoxication are briefly outlined. The absorption, distribution and elimination of alcohol in the human body are covered as background for understanding the passage of alcohol from blood to breath. Research on the blood/breath alcohol ratio and the factors that influence this relationship including mouth-alcohol, regurgitation, breathing technique, arteriole-venous differences, blood hematocrit value, pulmonary disease, body temperature, expired air temperature and temperature and humidity of ambient air are critically evaluated and discussed. Both blood-alcohol and breath-alcohol measurements are suitable to provide objective evidence of alcohol load in the organism and the associated impairment of driving skills. With per se statutes, the magnitude of sampling and analytical errors inherent in methods of analyzing alcohol for legal purposes must be carefully documented. The final prosecution result can be adjusted to allow for uncertainties in the analytical procedures used.
Normann, et al; Measurement of Ethanol by Alkomat Breath Analyzer. Chemical specificity and the influence of lung function, breath technique and environmental temperature 25 Blutalkohol 153 (1988)
Rose and Furton, Variables Affecting the Accuracy and Precision of Breath Alcohol Instruments Including the Intoxilyzer 5000
Simpson, Accuracy and Precision of Breath Alcohol Measurements for Subjects in the Absorptive State, 33(6) Clin. Chem. 753 (June 1987)
Published data are analyzed in order to estimate the accuracy of breath-alcohol measurements for subjects during absorption of orally ingested ethanol. Simultaneous measurements of breath alcohol concentration (BrAC) and venous blood alcohol concentration (VBAC) show that actual VBAC can be overestimated by more than 100% for a significant amount of time after drinking stops. The maximum error found for four individual subjects is +230%, +190%, +60%, and +30%. The magnitude of these errors indicates that results from quantitative evidential breath alcohol analyzers are far less accurate for the absorptive state than they are during the postabsorptive state, but the specifications for accuracy and precision given by manufacturers of these instruments do not reflect this. The results also indicate that there is a significant likelihood that subjects will be in the absorptive state when tested under field conditions. I conclude that estimates of BAC based on BrAC measurements are not reliable in the absorptive state and that the uncertainty associated with such estimates should be accounted for, particularly when the results are used in connection with law enforcement.
Abstract courtesy of www.pubmed.org – A service of the National Library of Medicine and the National Institutes of Health
Simpson, Accuracy and Precision of Breath-Alcohol Measurements for a Random Subject in the Postabsorptive State, 33 Clinical Chemistry 261 (1987)
The accuracy of estimates of blood-alcohol concentration based on measurements of breath-alcohol concentration in a randomly selected subject by a random quantitative evidential breath-alcohol analyzer is evaluated with respect to the breath analyzer itself, its calibration, and the biological variables of the subject being tested. There are no suitable experimental data for rigorous determination of the overall accuracy, so I estimate it from the CV of the available data. I find that the uncertainty in these breath-analyzer readings for a random subject in the postabsorptive state is at least +/- 15%, +/- 19%, or +/- 27%, depending on whether +/- 2 CV, the experimental range, or +/- 3 CV, respectively, is used to express the overall uncertainty. Over 90% of this uncertainty is due to biological variables of the subject, and at least 23% of subjects will have their actual blood-alcohol concentration overestimated. Manufacturers' specifications for the accuracy and precision of these instruments are inconsistent with the experimental values reported in the literature and I recommend that an appropriate amount of uncertainty be reflected in the results from these breath analyzers, especially when they are used for law-enforcement purposes.
Abstract courtesy of www.pubmed.org – A service of the National Library of Medicine and the National Institutes of Health
Simpson, Corrections to a Report, 33(11) Clin Chem 2130 (Nov 1987)
Simpson, Do Breath Tests Really Underestimate Blood Alcohol Concentration? 13(2) Journal of Analytical Toxicology, 120 (Mar-Apr 1989)
It has been reported that in the fully postabsorptive state, breath test results underestimate actual blood alcohol concentration (BAC) in 86% of the population. Reanalysis of the data on which this conclusion was based indicates 77% of these subjects were actually underestimated, and 23% were overestimated. Further refinements indicate 68% had their actual BAC underestimated, 16% were acceptably close to the actual BAC, and 16% were overestimated. Perhaps more importantly, comparison of this data with other results indicates fully postabsorptive status may not occur until more than three hours after drinking. Consequently, breath test results may tend to overestimate actual BAC for significant amounts of time after the peak BAC has been reached.
Abstract courtesy of www.pubmed.org – A service of the National Library of Medicine and the National Institutes of Health
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Gender and Race
Frezza & Lieber, High Blood Alcohol Levels in Women: The Role of Decreased Gastric Alcohol Dehydrogenase Activity and First-Pass Metabolism, 322 (2) New England Journal of Medicine 95 (1990)
After consuming comparable amounts of ethanol, women have higher blood ethanol concentrations than men, even with allowance for differences in size, and are more susceptible to alcoholic liver disease. Recently, we documented significant "first-pass metabolism" of ethanol due to its oxidation by gastric tissue. We report a study of the possible contribution of this metabolism to the sex-related difference in blood alcohol concentrations in 20 men and 23 women. Six in each group were alcoholics. The first-pass metabolism was determined on the basis of the difference in areas under the curves of blood alcohol concentrations after intravenous and oral administration of ethanol (0.3 g per kilogram of body weight). Alcohol dehydrogenase activity was also measured in endoscopic gastric biopsies. In nonalcoholic subjects, the first-pass metabolism and gastric alcohol dehydrogenase activity of the women were 23 and 59 percent, respectively, of those in the men, and there was a significant correlation (rs = 0.659) between first-pass metabolism and gastric mucosal alcohol dehydrogenase activity. In the alcoholic men, the first-pass metabolism and gastric alcohol dehydrogenase activity were about half those in the nonalcoholic men; in the alcoholic women, the gastric mucosal alcohol dehydrogenase activity was even lower than in the alcoholic men, and first-pass metabolism was virtually abolished. We conclude that the increased bioavailability of ethanol resulting from decreased gastric oxidation of ethanol may contribute to the enhanced vulnerability of women to acute and chronic complications of alcoholism.
Abstract courtesy of www.pubmed.org – A service of the National Library of Medicine and the National Institutes of Health
Milne, Canfield, Gallagher, Hunt, Klevay, Ethanol Metabolism in Postmenopausal Women Fed a Diet Marginal in Zinc, 46 American Journal of Clinical Nutrition 688 (1987)
Five postmenopausal women aged 50-63 y were fed a diet of mixed Western foods that supplied an average of 2.6 mg zinc/d for 6 mo. Plasma zinc did not change significantly during Zn depletion but increased slightly when Zn was fed. Zn content of blood cellular components and activities of Zn-containing enzymes were not affected by Zn intake. Ethanol tolerance tests performed at the end of control, middle of depletion, end of depletion, and end of repletion showed a change in ethanol metabolism at the end of the low-Zn intake period that was corrected within 1 mo with Zn supplementation. These data suggest that there are homeostatic mechanisms that maintain circulating levels of Zn. Zn and activity of Zn enzymes in tissues may be decreased before changes in circulating Zn levels are seen. Functional indices of Zn biochemistry, such as ethanol metabolism, may be more sensitive indicators of Zn stores and nutriture than circulating Zn.
Abstract courtesy of www.pubmed.org – A service of the National Library of Medicine and the National Institutes of Health
Kevin’s summary: Zinc deficiency = High BAC
Papple, The Effect of Oral Contraceptive Steroids on the Rate of Post-Absorptive Phase Decline of BAC in Adult Women, 15 Canadian Society of Forensic Science Journal (1982)
Wolff, Ethnic Differences in Alcohol Sensitivity, 175 Science 449 (1972)
Japanese, Taiwanese, and Koreans, after drinking amounts of alcohol that have no detectable effect on Caucasoids, respond with a marked facial flushing and mild to moderate symptoms of intoxication. Group differences are present at birth, and are probably related to variations in autonomic reactivity.
Kevin’s summary: 84% of the Asian subjects responded to measure al. with flush face
Yoshida, et al., Molecular Genetics of Alcohol-Metabolizing Enzymes, 16 Biochemical Society Transactions 230 (1988)
Remarkable racial differences is isoenzyme components of the ethanol metabolizing enzymes, i.e. the class I alcohol dehydrogenase [alcohol: NAD oxidoreductase (ADH), EC 1.1.1.1] and the aldehyde dehydrogenase [aldehyde: NAD oxidoreductase (ALDH), EC 1.2.1.3], in conjunction with the differences in alcohol sensitivity between Caucasians and Orientals, have been the subject of interest of biochemical and genetic studies in recent years. Liver ADH activity of about 90% of Orientals is several fold higher than that of most Caucasians (Stamatoyannopoulos et al., 1975), while approximately 50% of Orientals lack the activity of mitochondrial ALDH (ALDH2) in their livers and other issues (Harada et al., 1978). The enzyme differences, mainly the absence of the active ALDH2 component, and the consequent accumulation of acetaldehyde in the body, have been attributed to the high frequency of alcohol flushing in Orientals.
Kevin’s summary: 50% of Japanese lack one of the two types of ALDH
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Mouth Alcohol
Feeney, Horne & Williamson, Sobriety Testing: Intoxilyzers and Listerine Antiseptic, 52 Police Chief 70 (1985)
Kevin’s summary: Listerine rinse per label (30 sec)
.43 breath sample after 1 min
.20 breath sample after 3 min
.11 breath sample after 5 min
.01 breath sample after 10 min (one guy had .03 still)
Gaylarde, Stambuk & Morgan, Reductions in Breath Ethanol Readings in Normal Male Volunteers Following Mouth Rinsing with Water at Differing Temperatures, 22 Alcohol & Alcoholism 113 (1987)
Blood ethanol concentrations were measured sequentially, over a period of hours, using a Lion AE-D2 alcolmeter, in 12 healthy male subjects given oral ethanol 0.5 g/kg body wt. Readings were taken before and after rinsing the mouth with water at varying temperatures. Mouth rinsing resulted in a reduction in the alcolmeter readings at all water temperatures tested. The magnitude of the reduction was greater after rinsing with water at lower temperatures. This effect occurs because rinsing cools the mouth and dilutes retained saliva. This finding should be taken into account whenever breath analysis is used to estimate blood ethanol concentrations in experimental situations.
Abstract courtesy of www.pubmed.org – A service of the National Library of Medicine and the National Institutes of Health
Kevin’s summary: People should be told to rinse! Rinsing with cold water lowered BAC level twice as much. Reduces salivary ethanol in oral cavity. Relates to Hlastala’s paradigm. As air passes over oral saliva which is cooled and diluted there is less vapor pressure.
Gullberg, The Inadequacy of Instrumental “Mouth Alcohol” Detection Systems in Forensic Breath Alcohol Measurement, Washington State Patrol
Gullberg, Breath Alcohol Analysis in One Subject with Gastroesophageal Reflux Disease, 46 J Forensic Sci 1498 (2001)
A large number of people suffer from the heartburn symptoms associated with gastroesophageal reflux disease (GERD). Relatively little has been published on its potential for biasing a breath alcohol measurement. The present case described an individual (white male, aged 23) who experimentally consumed 1.0 g/kg of an alcohol beverage and subsequently provided breath and blood samples for analysis. Breath expirograms were also collected following several different pre-exhalation breathing maneuvers. Shortly after the end of drinking the mean of replicate breath alcohol results exceeded that of the corresponding venous blood alcohol. A later paired comparison (during the post absorptive phase) showed the blood alcohol to exceed the breath. None of the expirograms provided evidence that “mouth alcohol” due to gastroesophageal reflux has biased any test results. People with GERD can provide biased-free end-expiratory breath alcohol results where sound forensic practice is followed, which includes: 15-min. pre-exhalation observation, duplicate testing, instrumental detector systems, and trained alert operators who ask appropriate questions and watch for associated signs.
Harding, et. al., The Effect of Dentures and Denture Adhesives on Mouth Alcohol Retention, 37 Journal of Forensic Science 999, 1003 (july 1992)
A total of 24 alcohol-free, denture-wearing subjects were tested for mouth-alcohol retention times with an Intoxilyzer 5000. The subjects were given 30 mL doses of 80 proof brandy to swish in their mouths without swallowing for 2 min prior to expectorating the dose. Subjects were tested under three conditions: 1) with dentures removed, 2) with dentures held loosely in place without an adhesive, and 3) with dentures plus an adhesive. Beyond 20 min following expectoration, mouth alcohol made no significant contribution to the apparent breath alcohol concentration (BrAC), with trace (less than or equal to 0.01 g/210 L) readings found in only two of the subjects. Denture use, both with and without the concurrent use of adhesives does not significantly affect BrAC as long as a pretest alcohol deprivation period of 20 min is observed.
Abstract courtesy of www.pubmed.org – A service of the National Library of Medicine and the National Institutes of Health
Hlastala, The Slope Detector, Drinking Driving Law Letter, 15:153-157, (1996)
Jones, Reflection on the GERD Defense, DWI Journal; Law and Science 3 (2005)
Kechagias, Jonsson, Franzen, Andersson and Jones, Reliability of Breath-Alcohol Analysis in Individuals with Gastroesophageal Reflux Disease, 44 (4) J. Forensic Sci. 814, 814 (Jul. 1999)
Gastroesophageal reflux disease (GERD) is widespread in the population among all age groups and in both sexes. The reliability of breath alcohol analysis in subjects suffering from GERD is unknown. We investigated the relationship between breath-alcohol concentration (BrAC) and blood-alcohol concentration (BAC) in 5 male and 5 female subjects all suffering from severe gastroesophageal reflux disease and scheduled for antireflux surgery. Each subject served in two experiments in random order about 1-2 weeks apart. Both times they drank the same dose of ethanol (approximately 0.3 g/kg) as either beer, white wine, or vodka mixed with orange juice before venous blood and end-expired breath samples were obtained at 5-10 min intervals for 4 h. An attempt was made to provoke gastroesophageal reflux in one of the drinking experiments by applying an abdominal compression belt. Blood-ethanol concentration was determined by headspace gas chromatography and breath-ethanol was measured with an electrochemical instrument (Alcolmeter SD-400) or a quantitative infrared analyzer (Data-Master). During the absorption of alcohol, which occurred during the first 90 min after the start of drinking, BrAC (mg/210 L) tended to be the same or higher than venous BAC (mg/dL). In the post-peak phase, the BAC always exceeded BrAC. Four of the 10 subjects definitely experienced gastric reflux during the study although this did not result in widely deviant BrAC readings compared with BAC when sampling occurred at 5-min intervals. We conclude that the risk of alcohol erupting from the stomach into the mouth owing to gastric reflux and falsely increasing the result of an evidential breath-alcohol test is highly improbable.
Abstract courtesy of www.pubmed.org – A service of the National Library of Medicine and the National Institutes of Health
Kechagias, Johnsson, and Jones, Breath Tests for Alcohol in Gastroesophageal Reflux Disease, 130 Annals of Internal Medicine 328 (1999)
Logan, Gullberg, Lack of Effect of Tongue Piercing on an Evidential Breath Alcohol Test, 43 J. Forensic Sci. 239, (1998)
Defendants in several driving under the influence cases have asserted that the presence in the mouth of a metal stud through a hole pierced in the tongue invalidates the breath alcohol test because of the prohibition against foreign substances in the mouth, and because of the potential for the jewelry to retain alcohol and interfere with the breath test. Rates of mouth alcohol elimination were evaluated in two subjects with pierced tongues and in two control subjects. No difference in the mouth alcohol elimination patterns were observed. The 15 min alcohol deprivation period prior to the test ensures no effect from residual mouth alcohol. For the purpose of breath alcohol testing, oral jewelry should be treated in the same manner as dental work, and may be left in place during the test without affecting its outcome.
Simpson etal; Effects of Mouth Alcohol on Breath Alcohol Results, 3 International Journal of Drug Testing, 1
This study was conducted on 50 male subjects between 21 and 46 years of age. Each subject had his oral cavity searched for foreign matter and blood in the mouth, as well as producing a breath alcohol result of .00 prior to swishing a 1.75 ounce mixture of 75 percent alcohol in his mouth for 1 minute and then gargling the mixture for 20 seconds. The mixture was then expelled from the oral cavity. Alcohol Breath Tests (ABTs) were administered at 3 minutes and 7 minutes following the expelling of the mixture from the oral cavity. Results indicated the BAC DataMaster reported mouth alcohol in 48 percent of the trials with numerical values ranging between .02 and .43, while producing the “invalid sample” result on 52 percent of the trial. Conclusions include the inability of the slope detector algorithm incorporate to the BAC DataMaster to identify mouth alcohol in a meaningful set of circumstances. Inferences are made as to the importance of oral cavity search and direct observation during the fifteen minute waiting period.
Trafford & Makin, Breath Alcohol Concentration May Not Always Reflect the Concentration of Alcohol in Blood, 18 Journal of Analytical Toxicology 225 (1994)
A case is described of a 37-year-old man who was breath tested by the U.K. police following a traffic accident and was found to have a breath-alcohol concentration of 70 micrograms/100 mL--twice the U.K. legal limit. The defendant protested vigorously that he had not consumed sufficient alcohol to account for this excessive reading, and Widmark calculations, assuming his account of the alcohol consumed was accurate, suggested his contention was possibly correct. No evidence was obtained suggesting that the Lion Intoximeter used for the breath analysis was anything other than accurate. Alcohol loading tests were therefore carried out in the laboratory on two separate occasions, showing that breath-alcohol concentrations grossly in excess of the legal limit (140 micrograms/100 mL) were obtained when the amount of alcohol administered would have been expected to give a theoretical maximum of 35 micrograms/100 mL. A blood sample taken at the point when the breath-alcohol concentration was 70 micrograms/100 mL was shown to contain 54 mg of alcohol/100 mL of blood. Dental examination of the defendant showed that he had had extensive work carried out, including three bridges. A possible explanation, therefore, for these anomalous results is that the excessive breath-alcohol concentrations might be due to mouth alcohol retained in the bridges or periodontal spaces, although a careful fraud by the subject of this report cannot be ruled out.(ABSTRACT TRUNCATED AT 250 WORDS)
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Kevin’s summary: 37 YOA had BrAC twice the limit but blood under limit because dental work
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Partition Ratio
Borkenstein et al. Statement, Ad Hoc Committee on the Breath/Blood Alcohol Relationship. Indianapolis.Ind.U.law school Jan 1972
Kevin’s summary: Borkenstein, Dubowski, Forney, Sr., Harger, Goldber announced the partition ration principle:
2.1 liters of expired alveolar air contains approximately the same quantity of alcohol as 1 milliliter of blood. They declared the 2100:1 partition ration warranted.
Giguiere & Simpson, Medicolegal Alcohol Determination: In Vivo Blood/Breath Ratios as a Function of Time, Proceedings of the 27th Meeting of the International Association of Forensic Toxicologists 494 (Oct. 1990)
Kevin’s summary: Absorption Averages 50 minutes
Jones, Viability of the blood: Breath Alcohol Ration in Vivo, 39(1) Journal of Studies on Alcohol 1931 (1978)
The blood:breath alcohol ratio, commonly used to translate the result of breath alcohol analysis into the co-existing blood alcohol concentration, varies from person to person and within one person over time.
Abstract courtesy of www.pubmed.org – A service of the National Library of Medicine and the National Institutes of Health
Labianca, Simpson, Mediolegal Alcohol Determination: Variability of the Blood – to Breath –Alcohol Ration and Its Effect on Reported Breath Alcohol Concentrations, 33 Eur. J. Clin. Chem. Clin. Biochem 919, 919 (1995)
There is substantial agreement among scientists that the variability of a person's blood- to breath-alcohol ratio contributes significantly to the experimental error in results from breath-alcohol analysis. Some have argued that the need to correct for this source of error can be eliminated by reporting breath test results in units of breath-alcohol concentration rather than blood-alcohol concentration. A simple mathematical proof is presented to demonstrate that this is not the case. Moreover, the scientific and legal flaws of this argument are discussed, and recommendations are offered for dealing with the problems that have developed from adoption of this view.
Abstract courtesy of www.pubmed.org – A service of the National Library of Medicine and the National Institutes of Health
Labianca. The Chemical Basis of the Breathalyzer, 67 Journal of Chemical Education 259 (1990)
Labianca, The Flawed Nature of the Calibration Factor in Breath-Alcohol Analysis, 79 Journal of Chemical Education 1237 (2002)
Mason and Dubowski, Alcohol, Traffic, and Chemical Testing in the United States: a resume and some remaining problems. Clin.Chem 20:126-140, 1974
Mason and Dubowski, Breath –Alcohol Analysis: Uses, Methods and Some Forensic Problems: Review and Opinion. 21 Journal of Forensic Sciences 9 (1976)
Breath analysis for ethanol, especially in respect to the forensic aspects, has been reviewed. Included are matters dealing with instrumentation, physiological factors involved in the elimination of ethanol via the breath, and, especially, the uncertainties in the calculation of a whole blood concentration of ethanol from the quantity found in breath. We believe that the conversion of a breath quantity to a blood concentration of ethanol, for forensic purposes, should be abandoned and that the offense of driving while under the influence of alcohol should be statutorily defined in terms of the concentration of ethanol found in the breath in jurisdictions employing breath analysis. The breath sample should be obtained and analyzed only with instruments having capabilities which would require some extension of present federal standards for evidential breath-testing devices. Events in early 1975 indicate that implementation of some of these proposals may soon be undertaken.
Abstract courtesy of www.pubmed.org – A service of the National Library of Medicine and the National Institutes of Health
Kevin’s summary: Abandon the breath to blood conversion, retrograde extrapolation has too many factors to be reliable
Tsukamoto etal., An Experimental Study on the Ethanol Concentration Ratios of Breath to Body Fluid, 25 Nihon University Journal of Medicine 281 (1983)
We studied the breath/body fluid (blood, salive and urine) ethanol concentration ratios by gas chromatography and with an Alcohol meter AM -481 (Shinano Electric Co.). This paper examines the possibility of estimating the body fluid ethanol concentrations from the breath ethanol concentration. When the breath/body fluid ethanol concentration ratios were plotted on graph paper, the peak was 1:2400 by gas chromatography and 1:2600 with the Alcohol meter AM-481. It is suggested that, although the body fluid ethanol concentrations can to some extent be estimated by analyzing breath for ethanol, it is difficult to give a definite ratio since the ethanol distribution varies considerably with time.
Kevin’s summary: The partition ratio varies greatly between people and particularly between the absorption phase and elimination phase.
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Specificity
Bell, et al., Diethyl Ether Interference with Infrared Breath Analysis, 16 Journal of Analytical Toxicology (1992)
Diethyl ether vapor may substantially interfere with breath alcohol analysis by instruments based on infrared absorption at 9.5 microns. Exposure of two volunteers simultaneously to diethyl ether vapor for one hour followed immediately by breath tests on the Draeger Alcotest 7110, Siemens Alcomat V5.2F, and Seres Ethylometre 679T produced apparent alcohol readings in one subject of 0.4, 0.1, and 0.1 g/100 mL of blood respectively. Positive readings persisted in this subject for more than 3 hours. The second subject produced much lower readings of 0.03, 0.01, and 0.00, respectively. Readings persisted with the Alcotest 7110 for one hour. Gas chromatographic analyses of blood and breath samples confirmed that these readings were caused by diethyl ether and not ethanol. The blood concentration of diethyl ether in Subject A immediately after exposure was 25 mg/L. This level produced no clinically detectable neurological changes in the subject.
Abstract courtesy of www.pubmed.org – A service of the National Library of Medicine and the National Institutes of Health
Kevin’s summary: Diethyl ether interfered with breathtests at 9.5 microns. Diethyl ether is found in auto products, used to manufacture plastics and smokeless gunpowder.
Bosch, Xavier, Using Asthma Inhalers Can Give False Positive Results in Breath Tests, 324 British Medical Journal, 756 (2002)
Kevin’s summary: Inhalers without ethanol produced false positives for ethanol when subjects given breath tests within 10 minutes. Dr. Ignacio-Garcia suggests that the propellants are the cause.
Brick, Diabetes, Breath Acetone and Breathalyzer Accuracy: A Case Study, 9 (1) Alcohol, Drugs and Driving (1993)
In this case study, blood glucose and breath alcohol were measured and behavioral observations were made of a hypoglycemic 42-year-old male diabetic immediately prior to receiving insulin treatment. The subject’s blood glucose levels ranged from 53 mg/dL to less than 40 mg/dL. Near simultaneous Breathalyzer test results were generally less than .01%. The results suggest that although hypoglycemia in diabetics produces behavioral symptoms of gross alcohol intoxications, even extreme physiological changes in blood chemistry do not alter the results of a Breathalyzer test by more than .01%.
Kevin’s summary: Ketones in breath = erroneous high BAC
Caldwell & Kim, The Response of the Intoxilyzer 5000 to Five Potential Interfering Substances, 42 (6) Journal of Forensic Sciences 1080, 1084 (1997)
A study was conducted of potential vapor phase interferents which could be present on human breath and also be capable of inducing a false-positive response for ethanol on the evidential infrared-based breath testing device, the Intoxilyzer-5000. This involved preparation and validation of a range of vapor standards, which were introduced to the instrument using a dynamic flow double-bubbler system. Potential interferents were chosen on the basis of both their infrared signatures and their general availability, and included toluene, m-xylene, o-xylene, methanol and isopropanol. All compounds tested were found to be capable of inducing false-positive readings for ethanol in a highly reproducible manner, as a result of which it has been possible to derive precise least-squares equations describing the ethanol readout expected for any given blood concentration of toluene, m-xylene, o-xylene, methanol and isopropanol. The likelihood of an interference compromising the integrity of the analysis is related to both the toxicological significance and prevalence of a given blood concentration of each solvent, and the point at which the instrumental interference light is triggered in each case.
Abstract courtesy of www.pubmed.org – A service of the National Library of Medicine and the National Institutes of Health
Edwards, Giguiere, Lewis & Baselt, Intoxilyzer Interference by Solvents, 10(3) Journal of Analytical Toxicology 125, 125 (May-June 1986)
Giguiere, Lewis, Baselt, Chang, Lacquer fumes and the Intoxilyzer, 12 Journal of Analytical Toxicology 168, 168 (1988)
Kevin’s summary: Painter blows a .075 on Intoxilizer after painting with lacquer fumes for 20 minutes with mask. Then another ten minutes without mask blew .48
Janhanen, Baraona, Hiyakawa, and Lieber, Origin of Breath Acetaldehyde During Ehtanol Oxidation: Effects of Long-Term Cigarette Smoking, 100 Journal of Laboratory Clinical Medicine 908 (1982)
Oropharyngeal microflora and lung microcosms can produce acetaldehyde from ethanol. Therefore we evaluated the suitability of breath acetaldehyde analysis to estimate blood acetaldehyde. We found that in individuals who develop high acetaldehyde concentration (over 50 uM) after alcohol ingestion (such as oriental “flushers”), the acetaldehyde concentration in end-expiratory air reflects the blood levels. However, in the majority of non-Oriental subjects who develop very small concentrations of acetaldehyde in the blood (less than 5 uM), the production of acetaldehyde in the respiratory tract accounted for most of the acetaldehyde present in end-expiratory samples. Under the latter conditions, breath acetaldehyde did not correlate with blood levels. The production of acetaldehyde form ethanol in the respiratory tract was marked exaggerated in long-term cigarette smokers. Rinsing the oropharyngeal cavity with pyrazole (an alcohol dehydrogenase inhibitor) prior to sampling reduced, but did not eliminate, the local contribution to breath acetaldehyde, especially in smokers. In baboons, blood acetaldehyde could be accurately estimated from breath analysis only when the upper respiratory tract was completely excluded by collecting the expired air through an endotracheal tube. Thus, to assess blood acetaldehyde, breath acetaldehyde measurements cannot be substituted for direct measurements, except for those few conditions known to be associated with very high blood levels.
Kevin’s summary: Acetaldehyde greater than would be expected if just passing from liver to lungs via blood.
Acetaldehyde was greater in the lungs for smokers than non smokers.
See Stowell (1984)
Krotosyynski, Gabriel, O’Neil & Claudio, Characterization of Human Expired Air: A Promising Investigation and Diagnostic Technique, 15 Journal of Chromatographic Science 239 (1977)
Expired air samples have been collected from a carefully selected population of normal healthy human subjects under controlled experimental conditions. The samples were concentrated and analyzed by quantitative, reproducible and sensitive techniques which resulted in well-defined composite compositional and occurrence profiles of the organic constituents present in normal expired air. The composite profiles provide valuable baseline information upon which suitable correlation studies may be advanced toward the use of human expired air for diagnostic purposes.
Abstract courtesy of www.pubmed.org – A service of the National Library of Medicine and the National Institutes of Health
Kevin’s summary: 28 different subjects / 102 various organic compounds 70% of compounds common to 76% of population studied
Labianca, How Specific for Ethanol is Breath-Alcohol Analysis Based on Absorption of IR Radiation at 9.5 um? 16 Journal of Analytical Toxicology 404, 405 (Nov.-Dec. 1992)
Kevin’s summary: Breath testing lacks of specificity because thousands of organic molecules that contain the methyl group and the corresponding carbon-hydrogen bond absorb the light producing a false positive.
Logan & Distefano, Ethanol Content of Various Foods and Soft Drinks and their Potential for Interference with a Breath-Alcohol Test, 22 Journal of Analytical Toxicology 181 (1988)
A variety of breads and soft drinks were tested and found to contain low concentrations of alcohol. The potential for these products to generate false readings on an evidential breath-alcohol instrument was evaluated. Alcohol-free subjects ingested these products and then provided breath samples into DataMaster. It was found that breath samples provided immediately after consumption of some of these products, or with them still present in the mouth, did produce low levels of apparent breath alcohol, which may or may not be rejected as invalid by the breath-test instrument. If the subject swallowed or expectorated the food or beverage and then observe a 15 min deprivation period during which nothing was introduced into the mouth, the apparent effect was eliminated. These findings emphasize the need for the mandatory pretest alcohol-deprivation period and the benefits of duplicate breath sampling.
Kevin’s summary: Datamaster read up to .046 on bread etc. The mouth alcohol
Slope detector failed but, with all of our checks and protocols we reduce risk to zero
Manolis, The Diagnostic Potential of Breath Analysis, 29 Clinical Chemistry 5 (1983)
Kevin’s summary: 200 compounds found in breath; acetone can be found on the breath of diabetics and persons loosing ½ pound per week.
Mason and Dubowski, Breath as a Specimen for Analysis for Ethanol and Other Low-Molecular-Weight Alcohols, Medical-Legal Aspects of Alcohol 177, 180
Stowell, et al., A Reinvestigation of the Usefulness of Breath Analysis in the Determination of Blood Acetaldehyde Concentrations, 8 Alcoholism: Clinical and Experimental Research 442 (1984)
Human volunteers were given ethanol (0.4 g/kg) either intravenous or per os. They were also given ethanol (0.2 g/kg) intravenous 4 hr after receiving a dose of 50 mg citrated calcium carbimide, an aldehyde dehydrogenase inhibitor. During the first hour after starting the administration of ethanol, ethanol and acetaldehyde concentrations were determined in expired air, blood from the right atrium, arterial blood, and venous blood. In the absence of calcium carbimide treatment, the respective maximal blood acetaldehyde concentrations were (range): 6-30 microM (calculated from breath analysis using a blood:breath partition ratio of 190 for acetaldehyde); 0-3.5 microM (right atrium blood); and 0 microM (arterial and venous blood). After calcium carbimide treatment, the maximal blood acetaldehyde concentrations were 10-220 microM (calculated from concentrations in expired air), 38-280 microM (right atrium), 31-250 microM (arterial blood), and 7-186 microM (venous blood). With aldehyde dehydrogenase inhibition, a clear correlation existed between breath concentrations and blood concentrations. Without this inhibition, no such correlation was found. A clear arterio-venous difference was seen for acetaldehyde concentrations while they were artificially elevated by calcium carbimide. Our study suggests that factors other than the equilibration of acetaldehyde between alveolar air and pulmonary blood are of great importance in determining the concentration of acetaldehyde in expired air.
Abstract courtesy of www.pubmed.org – A service of the National Library of Medicine and the National Institutes of Health
Kevin’s summary: Acetaldehyde was coming not from the liver but the lungs! Showing BAC 30 times higher
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Temperature
Bell, What About the Humble Mouthpiece? Breath Sample Modification and Implications for Breath Alcohol Analysis, Victoria Forensic Science Centre
The modifying effect of the mouthpiece used in breath alcohol analysis was examined in terms of alcohol concentration in, and temperature of, the sample delivered. With repetitive testing, the standard Disposable Products mouthpiece (generally used for evidential breath analyses in Australia) was examined using a simulated blood alcohol concentration (BAC) of 0.250 g/100mL, delivery flowrate of 12 L/min and delivery volume of 2.5 L. The measured BAC and temperature values for tests with and without a mouthpiece were signicantly different (p< 0.0001) and the differences averaged 0.0020 g/100mL and 1.0 °C respectively. Using an Allplastics brand mouthpiece, the reduction in BAC and temperature were 0.0027 g/100mL and 1.8 °C. Further testing using the Disposable Products mouthpiece pre-warmed (40 °C) and cooled (3 °C), when compared to using a mouthpiece at 20 °C, did not significantly alter BAC, but increased and decreased the measured temperature by 1.0 and 0.6 °C respectively (p<0.0001). The temperature reduction using a Disposable Products mouthpiece and a human subject who provided breath samples in a standardised fashion, was 1.0 °C. The conclusions are that the mouthpiece modifies the breath sample delivered, lowering both BAC and temperature. The variations in BAC and temperature do not correlate with the change in alcohol air/water partition ratio of 6.7% per degree. Therefore, the correction of BAC readings to a standardised temperature (of 34.0 °C) is not straightforward.
Carpenter and Buttram, Breath Temperature: An Alabama Perspective, 9 IACT Newsletter 16, 16 (July 1998)
Kevin’s summary:
1. One reason the Draeger Alcotest is better than Datamaster is because it measures breath temperature
2. Reviewing “Modern” literature 34° is not average. 35° is average.
3. Schokneckt says 33 - 36.7° range.
Dubowski, Studies in Breath-Alcohol Analysis: Biological Factors, 76 International Journal of Legal Medicine 93 (1975)
Various biological factors affecting breath-alcohol analysis were studied experimentally. End-expiratory temperatures in 55 healthy subjects were found to range from 32.41 to 35.69 degrees C with a mean of 34.53 degrees C. Forced vital capacity in the same subjects ranged from 1825 to 6550 ml with a mean of 4038 ml, and maximum exhalation after normal inhalation ranged from 1180 to 4550 ml with a mean of 2730 ml. It was found that 65-70% of available breath must be discarded before the alveolar plateau is reached during expiration. End-expiratory (alveolar) carbon dioxide in 155 healthy subjects was 3.5-8.3% by volume (mean = 6.52). After oral alcohol intake, retained mouth-alcohol in 8 subjects had disappeared after 11 minutes without subsequent water-rinsing of the mouth, and after 8 minutes with rinsing. Water condensation in plastic mouthpieces/saliva traps during breath sampling yielded mean weight gains of 13.0, 8.6, and 4.6 mg., respectively, at initial mouthpiece temperatures of 3 degrees C, 22.5 degrees C, and 34.7 degrees C, respectively.
Abstract courtesy of www.pubmed.org – A service of the National Library of Medicine and the National Institutes of Health
Fox and Hayward, Effects of Hyperthermia on Breath Alcohol Analysis 34 Journal of Forensic Sciences 320 (1987)
Mild hyperthermia to the extent of a 2.5"C Increase above normal body temperature was produced by immersion of ethanol-intoxicated subjects in a warm water bath. Hyperthermia did not influent- the blood-alcohol decay curve of the subjects. Hyperthermia did cause a significant distortion of the breath-alcohol decay curve, up to as much as a 23% increase above blood-alcohol concentration. The magnitude of this distortion effect was calculated to be a 8.62% increase in breath-alcohol concentration over blood-alcohol concentration for each °C Increase in core body temperature. The forensic relevance of these results is that further support is given to previous recommendations that temperature monitoring be included in procedures for breath-alcohol analysis. This leads to the recommendation that mouth temperature be measured before breath sampling to screen for abnormal body temperature and to allow for potential use of a "temperature correction factor." This modification to existing analytical procedures would optimize the reliability of breath-ethanol analysis for prediction of blood-ethanol concentration.
Kevin’s summary: Hyperthermia causes up to a 23% increase of breath alcohol over blood alcohol. 8.62% increase of breath alchol over blood alcohol per degree Celsius increase in core body temperature.
Mouth temperature should be measured to allow a temperature correction factor.
Jones, Effect of Temperature and Humidity of Inhaled Air on the Concentration of Ethanol in a Man’s Exhaled Breath, 63 Clinical Science 441, 441 (1982)
Jones, Medicolegal Alcohol Determinations – Blood-or Breath-Alcohol Concentrations? 12 Forensic Science Review 23, 42 (Jan. 2000)
McMurray, Breath Temperature and Breath Alcohol Analysis, 20 DWI Journal: Law and Science, 5 (2005)
Ohlson, etal., Accurate Measurement of Blood Alcohol Concentration with Isothermal Rebreathing, 51 (1) Journal of Studies on Alcohol 6 (1990)
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Driver's Impairment
Barkley etal; Effects of Two Doses of Alcohol on Simulator Driving Performance in Adults with Attention-Deficit/Hyperactivity Disorder, 20 Neuropsychology, 77 (2006)
Prior studies have documented greater impairments in driving performance and greater alcohol consumption among adults with attention-deficit/hyperactivity disorder (ADHD). This study examined whether alcohol consumption produces a differentially greater impairment in driving among adults with ADHD in comparison to a community control group. The present study compared 50 adults with ADHD (mean age 33 years) and 40 control adults (mean age 29 years) on the effects of 2 single, acute doses of alcohol (0.04 and 0.08 blood alcohol concentration) and a placebo on their driving performance. The authors used a virtual reality driving simulator, examiner and self-ratings of simulator performance, and a continuous performance test (CPT) to evaluate attention and inhibition. Approximately half of the adults in each group were randomized to either the low or high dose alcohol treatment arms. Alcohol consumption produced a greater impact on the CPT inattention measures of the ADHD than the control group. Similar results were obtained for the behavioral observations taken during the operation of the driving simulator. Driving simulator scores, however, showed mainly a deleterious effect of alcohol on all participants but no differentially greater effect on the ADHD group. The present results demonstrated that alcohol may have a greater detrimental effect on some aspects of driving performance in ADHD than control adults.
Kevin’s summary: Alcohol does not have a worse effect on ADHD people. There may be a difference in some aspects of driving compared to a drivers vigilance but more research is needed as this study is inconclusive.
Kruger, Kazenwadel, Vollrath; Grand Rapids Effects Revisited: Accidents, Alcohol and Risk, Center for Traffic Sciences, University of Wuerzburg, Rontgenring 11, D-97070 Wurzburg, Germany
Risk analysis is based on information collected about both exposure to danger and the dangerous event itself. In the case of alcohol-related accident risk, information is needed about the prevalence of driving under the influence of alcohol (DUI) and the frequency with which DUI drivers are involved in accidents. These requirements were met in Borkenstein et al.’s Grand Rapids Study. However, one shortcoming of that study was the risk of causing an accident (rather than just being involved in an accident) had to be estimated because the authors did not know whether the drive was responsible for the accident. Our 1993 Accident Study collected information about BAC, responsibility for causing the accident, and driver characteristics for all drivers in 4,615 accidents. The information about exposure was taken from the German Roadside Survey, which samples 13,149 drivers in 1993. Using those data, the well-known risk function of Borkenstein et al. was replicated. However, the BAC distribution for drivers involved in an accident but not responsible for it was markedly different from that for the drivers in the Roadside Survey. In calculating risk function, Borkenstein et al. assumed identical distributions for these two samples. It can be shown that the problematic “dip” in the risk function was at least in part caused by this assumption.
Neale etal, An Overview of the 100-Car Naturalistic Study and Findings
A key to the development of effective crash countermeasures is an understanding of pre-crash causal and contribution factors. This research effort was initiated to provide an unprecedented level of detail concerning driver performance, behavior, environment, driving contact and other factors that were associated with critical incidents, near crashes and crashes for 100 drivers across a period of one year. A primary goal was to provide vital exposure and pre-crash data necessary for understanding causes for crashes, supporting the development and refinement of crash avoidance countermeasures, and estimating the potential of these countermeasures to reduce crashes and their consequences.
Richards etal: Driving Anger and Driving Behavior in Adults with ADHD, 10 Journal of Attention Disorders, 56 (2006)
This study assesses whether anger in the context of driving is associated with the negative driving outcomes experienced by individuals with ADHD. ADHD adults (n = 56) complete measures of driving anger, driving anger expression, angry thoughts behind the wheel, and aggressive, risky, and crash-related behavior. Results are compared to two non ADHD control groups; one from the same community as the ADHD sample (n = 106) but that did not complete all instruments and the other from college students (n = 432) who completed all instruments. ADHD participants report more driving anger and aggressive expression through the use of their vehicle and less adaptive and constructive anger expression than theirnon-ADHD peers. Adult ADHD drivers rate themselves as more angry, risky, and unsafe drivers and report experiencing more losses of concentration and vehicular control than college students. Results are discussed with regard to driving-related problems for drivers with ADHD
Kevin’s summary: 3 limitations
1. Subject groups not identically matched
2. Gender only 15 females with ADHD they described themselves as more risky than ADHD males.
3. Self reporting was the method of data collection.
This study says that ADHD people are less emotionally inhibited than non ADHD people and therefore are move risky drivers because they act on their anger.
The officers statement that your client was emotional and therefore drunk might have been just ADHD
Sexton, etal; The Influence of Cannabis on Driving, Prepared for Road Safety Division, Department of the Environment, Transport and the Regions, (2000)
Silber, The acute effects of d-amphetamine and methamphetamine on attention and psychomotor performance, 187 Psychopharmacology 154 (2006)
It is not clear how the deleterious effects of amphetamines on driving performance are mediated in terms of select cognitive processes. The current three separate experiments assessed the acute effects of an oral dose of either 0.42-mg/kg d-amphetamine, d,l-methamphetamine and d-methamphetamine on driving –related cognitive functions in a total of 60 healthy non-fatigued adults. Three separate repeated measures counterbalanced, double-blind, placebo-controlled designs were employed in which 20 volunteers completed two treatment conditions, either d-amphetamine, d,l-methamphetamine or d-methamphetamine and placebo. Performance was assessed on a range of attentional, psychomotor and perceptual speed tasks. Mean blood concentrations at 120-,170- and 240-min postdrug administration were 83,98 and 96ng/ml respectively, for d,l-amphetamine and , 90, 95 and 105 ng/ml, respectively, for d,l-methamphetamine and 72, 67 and 59 ng/ml, respectively, for d-methamphetamine. The amphetamines, in general, improved various aspects of attention (Digit vigilance, Digit Symbol Substitution Test and Movement Estimation Performance) with some evidence to suggest possible enhancement in psychomotor functioning (Tracking ability) and perceptual speed (Inspection Time). The current series of studies primarily provides evidence of low level amphetamine-related enhancement of function; however, it also provides evidence of less conservative movement estimation that might contribute to amphetamine-related road fatalities.
Strayer, Drews, Crouch; A Comparison of the Cell Phone Driver and the Drunk Driver, 4-13 Joint Center, (2004)
We used a high fidelity driving simulator to compare the performance of cell-phone drivers with drivers who were legally intoxicated from ethanol. When drivers were conversing on either a hand-held or hands-free cell-phone, their braking reactions were delayed and they were involved in more traffic accidents than when they were not conversing on the cell phone. By contract, when drivers were legally intoxicated they exhibited a more aggressive driving style, following closer to the vehicle immediately in front of them and applying more force while braking. When controlling for driving conditions and time on task, cell-phone drivers exhibited greater impairment than intoxicated drivers. The results have implications for legislation addressing driver distraction caused by cell phone conversations.
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Endogenous Articles
Jones, Mardh, and Anggard, Determination of Endogenous Ethanol in Blood and Breath by Gas Chromatography – Mass Spectometry, 18 Pharmacology, Bid Chemistry and Behavior 267-272 (Supp 1, 1983)
We describe methods for the determination of endogenous ethanol in biological specimens from healthy abstaining subjects. The analytical methods were headspace gas chromatography (GC) for plasma samples and gas chromatography-mass spectometry (GC/MS) with deuterium labelled species 2H3-ethanol and 2H5-ethanol as internal standards for breath analysis. Ethanol in rebreathed air was about 10% higher than in directly analysed end-expired alveolar air. Known volumes of rebreathed air were passed through a liquid-N2 freeze trap and the volatile constituents of breath were concentrated prior to analysis by GC or GC/MS. Besides endogenous ethanol, peaks were seen on the chromatograms for methanol, acetone and acetaldehyde as well as several as yet unidentified substances. The endogenous alcohols ethanol and methanol were confirmed from their mass chromatograms and the GC/MS profile also indicated the presence of endogenous propan-1-ol. The concentration of endogenous ethanol in plasma showed wide inter-subject variations ranging from below detection limits to 1.6 micrograms/ml (34.8 mumol/l) and with mean +/- SD of 0.39 +/- 0.45 micrograms/ml (8.5 +/- 9.8 mumol/l). We aim to characterise further the role of endogenous ethanol with the main focus on dynamic aspects such as the rate of formation and turnover.
Abstract courtesy of www.pubmed.org – A service of the National Library of Medicine and the National Institutes of Health
Kevin’s summary: This study establishes the existence of endogenous ethanol by use of GC-M.Spect
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Fatigue Articles
Arnedt, Owens, Crouch, Stahl, Carskadon, Neurobehavioral Performance of Residents After Heavy Night Call vs. After Alcohol Ingestion 294(9) JAMA 1025-1033 (2005)
CONTEXT: Concern exists about the effect of extended resident work hours; however, no study has evaluated training-related performance impairments against an accepted standard of functional impairment. OBJECTIVES: To compare post-call performance during a heavy call rotation (every fourth or fifth night) to performance with a blood alcohol concentration of 0.04 to 0.05 g% (per 100 mL of blood) during a light call rotation, and to evaluate the association between self-assessed and actual performance. DESIGN, SETTING, AND PARTICIPANTS: A prospective 2-session within-subject study of 34 pediatric residents (18 women and 16 men; mean age, 28.7 years) in an academic medical center conducted between October 2001 and August 2003, who were tested under 4 conditions: light call, light call with alcohol, heavy call, and heavy call with placebo. INTERVENTIONS: Residents attended a test session during the final week of a light call rotation (non-post-call) and during the final week of a heavy call rotation (post-call). At each session, they underwent a 60-minute test battery (light and heavy call conditions), ingested either alcohol (light call with alcohol condition) or placebo (heavy call with placebo condition), and repeated the test battery. Performance self-evaluations followed each test. MAIN OUTCOME MEASURES: Sustained attention, vigilance, and simulated driving performance measures; and self-report sleepiness, performance, and effort measures. RESULTS: Participants achieved the target blood alcohol concentration. Compared with light call, heavy call reaction times were 7% slower (242.5 vs 225.9 milliseconds, P<.001); commission errors were 40% higher (38.2% vs 27.2%, P<.001); and lane variability (7.0 vs 5.5 ft, P<.001) and speed variability (4.1 vs 2.4 mph, P<.001) on the driving simulator were 27% and 71% greater, respectively. Speed variability was 29% greater in heavy call with placebo than light call with alcohol (4.2 vs 3.2 mph, P = .01), and reaction time, lapses, omission errors, and off-roads were not different. Correlation between self-assessed and actual performance under heavy call was significant for commission errors (r = -0.45, P = .01), lane variability (r = -0.76, P<.001), and speed variability (r = -0.71, P<.001), but not for reaction time. CONCLUSIONS: Post-call performance impairment during a heavy call rotation is comparable with impairment associated with a 0.04 to 0.05 g% blood alcohol concentration during a light call rotation, as measured by sustained attention, vigilance, and simulated driving tasks. Residents' ability to judge this impairment may be limited and task-specific.
Abstract courtesy of www.pubmed.org – A service of the National Library of Medicine and the National Institutes of Health
Dawson, Reid, Fatigue, Alcohol, and Performance Impairments, Nature 388, 235 (1997)
Kevin’s summary: moderate fatigue = impaired driving
Equivalent to alcohol DUI impairment.
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Field Sobriety Tests Articles
Booker, End Position Nystagmus as an Indicator of Ethanol Intoxication 40(2) Science and Justice 113 – 116 (2001)
The Horizontal Gaze Nystagmus test is used by law enforcement agencies in the United States to determine whether drivers are intoxicated. It has a high baseline error and a dose/response relationship that varies greatly according to whether the subject's blood alcohol concentration is rising or falling. Confusion exists among practitioners of the test about whether it quantifies alcohol concentration or evaluates impairment. Fatigue exacerbates one component of the HGN test, end-position nystagmus. Video tapes recorded by cameras in police vehicles revealed that police officers rarely comply with the minimum requirements of the nystagmus examination procedures for which they were trained and certified.
Abstract courtesy of www.pubmed.org – A service of the National Library of Medicine and the National Institutes of Health
Kevin’s summary: Alcohol vs. Fatigue as the cause of HGN
55% False positives for fatigued nondrinkers.
Dose response relationship varies depending on absorptive vs. postabsorptive phase
More than 50% of subjects had positive HGN after BAC returned to 0.0
Booker, The Horizontal Gaze Nystamus Test; Fraudulent Science in the American Courts, 44 Science and Justice 133 (2004)
The Horizontal Gaze Nystagmus (HGN) test was conceived, developed and promulgated as a simple procedure for the determination of the blood alcohol concentration of drivers suspected of driving while intoxicated (DWI). Bypassing the usual scientific review process and touted through the good offices of he federal agency responsible fro traffic safety, it was rushed into use as a law enforcement procedure, and was soon adopted and protected from scientific criticism by courts throughout the United States. In fact, research findings, training manuals and other relevant documents were often held as secrets by the state. Still, the protective certification of its practitioners and the immunity afforded by judicial notice failed to silence all the critics of this deeply flawed procedure. Responding to criticism, the sponsors of the test traveled the path documented in this paper that led from mere (if that word can ever truly apply to a matter of such gravity) carelessness in research through self-serving puffery and finally into deliberate fraud – always at the expense of the citizen accused.
Bridges, Standardized Field Sobriety Tests Is Current Training Enough?, Criminal Justice Institute School of Law Enforcement Supervision (2004)
Busloff, Can Your Eyes Be Used Against You? The Use Of The Horizontal Gaze Nystagmus Test In The Courtroom, 84 Journal of Criminal Law and Criminology, 203 (1993)
Citek et al, Nystagmus Testing in Intoxicated Individuals, 74 Optometry 695 (2003)
Cole and Nowaczyk, Field Sobriety Tests: Are they Designed for Failure? 79 Perceptual and Motor Skills, 1994
Field sobriety tests have been used by law enforcement officers to identify alcohol-impaired drivers. Yet in 1981 Tharp, Burns, and Moskowitz found that 32% of individuals in a laboratory setting who were judged to have an alcohol level above the legal limit actually were below the level. In this study, two groups of seven law enforcement officers each viewed videotapes of 21 sober individuals performing a variety of field sobriety tests or normal-abilities tests, e.g., reciting one's address and phone number or walking in a normal manner. Officers judged a significantly larger number of the individuals as impaired when they performed the field sobriety tests than when they performed the normal-abilities tests. The need to reevaluate the predictive validity of field sobriety tests is discussed.
Abstract courtesy of www.pubmed.org – A service of the National Library of Medicine and the National Institutes of Health
Cole and Nowaczyk, Separating Myth from Fact: A Review of Research on the Field Sobriety Tests, Clemson University
Dell’Osso, Nystagmus, Saccadic Intrusions/Oscillations and Oscillopsia, 3 Current Neuro- Opthalmology, 147 (1989)
Doty, Wudarski, Marshall, Hastings, Marijuana Odor Perception: Studies Modeled From Probable Cause Cases, 28 (2) Law and Human Behavior (2004)
Franklin, Impediments to Testing: The Impact of Hearing Impairment and Language Barriers on the Field Sobriety Testing Function, National Sobriety Testing Resource Center (2005)
Han etal, Nystagmus while recumbent in horizontal canal benign paroxysmal positional vertigo, 66 Neurology, 706 (2006)
Background: The identification of the affected ear is crucial for the successful treatment of benign paroxysmal positional vertigo involving the horizontal canal (HC-BPPV) by using particle-repositioning maneuvers. Methods: The authors prospectively investigated lying-down nystagms in 152 consecutive patients with confirmed HC-BPPV (99 geotropic and 53 apogeotropic types). Lying-down nystagmus was induced by placing patients in a supine position. For the geotropic type of HC-BPPV, the affected ear was identified by assuming that nystagmus is more intense when the head is rotated to the affected side while supine. The reverse assumption was adopted for the apogeotropic type. Result: Lying-down nystagmus was observed in 58 patients (38.2%), 36 (36.4%) of the geotropic and 22 (41.5%) of the apogeotropic type. The direction of lying-down nystagmus was mostly away from the affected ear in the geotropic type, but toward the affected ear in the apogeotropic type. Of the 16 geotropic patients in whom the affected ear was not identified initially, 7 with lying-down nystagmus showed resolution of vertigo after particle-repositioning maneuvers when the involved ear was identified by observing lying-gown nystagmus. Conclusion: Lying-down nystagmus is a valuable sign for determining which ear is affected in benign paroxysmal positional vertigo involving the horizontal canal, especially when patients show symmetric nystagmus as turning the head to either side.
Halperin, Yolton; Is the driver drunk? Oculomotor sobriety testing, 57 Journal of the American Optometric Association 654, (1986)
Recently a new test involving observation of ocular pursuit movements, end-point nystagmus and angle of lateral deviation at which nystagmoid movements begin has been used by law enforcement agencies to determine the blood alcohol level of suspected drunk drivers. When properly administered and scored this test can correctly identify approximately 80% of drivers with alcohol levels of 0.10% or greater. The test is more accurate than the traditional coordination or mental computation tests previously used but questions may be raised about the use of the test with suspects who have ocular problems such as high refractive errors, chronic nystagmus, etc.
Hlastla, Polissar, Oberman, Statistical Evaluation of Standardized Field Sobriety Tests, 50(3) J Forensic Sci (2005)
Standardized Field Sobriety Tests (SFSTs) are used as qualitative indicators of impairment by alcohol in individuals suspected of DUI. Stuster and Burns authored a report on this testing and presented the SFSTs as being 91% accurate in predicting Blood Alcohol Concentration (BAC) as lying at or above 0.08%. Their conclusions regarding accuracy are heavily weighted by the large number of subjects with very high BAC levels. This present study re-analyzes the original data with a more complete statistical evaluation. Our evaluation indicates that the accuracy of the SFSTs depends on the BAC level and is much poorer than that indicated by Stuster and Burns. While the SFSTs may be usable for evaluating suspects for BAC, the means of evaluation must be significantly modified to represent the large degree of variability of BAC in relation to SFST test scores. The tests are likely to be mainly useful in identifying subjects with a BAC substantially greater than 0.08%. Given the moderate to high correlation of the tests with BAC, there is potential for improved application of the test after further development, including a more diverse sample of BAC levels, adjustment of the scoring system and a statistically-based method for using the SFST to predict a BAC greater than 0.08%.
Abstract courtesy of www.pubmed.org – A service of the National Library of Medicine and the National Institutes of Health
Marieb, Effects of Parasympathetic and Sympathetic Divisions on Various Organs, Human Anatomy and Physiology Sixth Edition.
Moskowitz, Burns, Ferguson, Police Officers’ Detection of Breath Odors from Alcohol Ingestion, 31(3) Accident Analysis and Prevention 175 (1999)
Police officers frequently use the presence or absence of an alcohol breath odor for decisions on proceeding further into sobriety testing. Epidemiological studies report many false negative errors. The current study employed 20 experienced officers as observers to detect an alcohol odor from 14 subjects who were at blood alcohol concentrations (BACs) ranging from zero to 0.130 g/dl. Over a 4 h period, each officer had 24 opportunities to place his nose at the terminal end of a 6 in. tube through which subjects blew. Subjects were hidden behind screens with a slit for the tube to prevent any but odor cues. Under these optimum conditions, odor was detected only two-thirds of the time for BACs below 0.08 and 85% of the time for BACs at or above 0.08%. After food consumption, correct detections declined further. Officers were unable to recognize whether the alcohol beverage was beer, wine, bourbon or vodka. Odor strength estimates were unrelated to BAC levels. Estimates of BAC level failed to rise above random guesses. These results demonstrate that even under optimum laboratory conditions, breath odor detection is unreliable, which may account for the low detection rate found in roadside realistic conditions.
Abstract courtesy of www.pubmed.org – A service of the National Library of Medicine and the National Institutes of Health
Kevin’s summary: 20 experiened officers failed to predict alcohol intoxication of 14 subjects with BACs from .00-.13. Also unable to differentiate between types of alcohol consumed.
Nicholson, et al., Variability in Behavioral Impairment Involved in the Rising and Falling BAC Curve, Journal of Studies on Alcohol 349 (July 1992)
The purpose of this pilot study was to measure variability in behavior impairment at specific levels of the rising and falling blood alcohol concentration (BAC) curve. Behavior impairment was measured for anticipation and reaction time in addition to a variety of visual skills. Also of interest was the variability in impairment involved at specific BAC levels under single-dose and double-dose conditions. The experimental design was a variation on a 2 x 2 factorial with repeated measures on the dose of alcohol. All subjects took part in two experimental sessions, single-dose and double-dose. Sixteen (8 male and 8 female) paid subjects ages 21-40 participated in the study. Testing procedures included repeated measures on reaction time, anticipation time, perceptual vision acuity and depth perception. Breath-alcohol measures were sampled continuously at 5-minute intervals and used to plot absorption time, peak BAC and elimination time. Results showed that the average peak BAC for the double-dose was significantly higher than that of the single-dose condition. However, there were no significant differences between the single-dose and double-dose condition in either absorption time or elimination time. The performance pattern for reaction time, anticipation time and depth perception showed more impairment in the rising BAC limb than in the falling BAC limb. It is noteworthy that specific individuals exhibited different levels of impairment at a given BAC level, depending on whether the session was single- or double-dose, suggesting that one's current BAC level is less a measure of impairment than is the total quantity of alcohol consumed. A follow-up procedure to examine practice effects was conducted on eight volunteer students. Identical testing procedures, using no alcohol, produced no significant practice effects after a 3-hour period.
Abstract courtesy of www.pubmed.org – A service of the National Library of Medicine and the National Institutes of Health
Kevin’s summary: Impairment is greater during rising phase than falling phase
Papafotiou, Carter, Stough, An evaluation of the sensitivity of the Standardized Field Sobriety Tests (SFSTs) to detect impairment due to marijuana intoxication, 180 Psychopharmacology 107 (205)
Redelmeier, Tibshirani, Association Between Cellular-Telephone Calls and Motor Vehicle Collisions, 336 (7) New England Journal of Medicine, 453-458 (1997)
BACKGROUND: Because of a belief that the use of cellular telephones while driving may cause collisions, several countries have restricted their use in motor vehicles, and others are considering such regulations. We used an epidemiologic method, the case-crossover design, to study whether using a cellular telephone while driving increases the risk of a motor vehicle collision. METHODS: We studied 699 drivers who had cellular telephones and who were involved in motor vehicle collisions resulting in substantial property damage but no personal injury. Each person's cellular-telephone calls on the day of the collision and during the previous week were analyzed through the use of detailed billing records. RESULTS: A total of 26,798 cellular-telephone calls were made during the 14-month study period. The risk of a collision when using a cellular telephone was four times higher than the risk when a cellular telephone was not being used (relative risk, 4.3; 95 percent confidence interval, 3.0 to 6.5). The relative risk was similar for drivers who differed in personal characteristics such as age and driving experience; calls close to the time of the collision were particularly hazardous (relative risk, 4.8 for calls placed within 5 minutes of the accident, as compared with 1.3 for calls placed more than 15 minutes before the accident; P<0.001); and units that allowed the hands to be free (relative risk, 5.9) offered no safety advantage over hand-held units (relative risk, 3.9; P not significant). Thirty-nine percent of the drivers called emergency services after the collision, suggesting that having a cellular telephone may have had advantages in the aftermath of an event. CONCLUSIONS: The use of cellular telephones in motor vehicles is associated with a quadrupling of the risk of a collision during the brief time interval involving a call. Decisions about regulation of such telephones, however, need to take into account the benefits of the technology and the role of individual responsibility.
Abstract courtesy of www.pubmed.org – A service of the National Library of Medicine and the National Institutes of Health
Sanders, News of Science, Medicine, and Technology: Straight Talk 21(10) Discover (2000)
Kevin’s summary: Harry Hollien, phonetician at University of Florida, used chemical dependency clinicians | 