Kurt M. Dubowski

Breath-alcohol analysis: uses, methods, and some forensic problems--review and opinion.

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.

Studies in breath-alcohol analysis: Biological factors

SummaryVarious 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° C with a mean of 34.53° 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° C, 22.5° C, and 34.7° C, respectively.ZusammenfassungEinige der Grundlagen, die für die Atemalkoholanalyse von Bedeutung sind, wurden experimentell untersucht.Bei 55 Versuchspersonen wurde die Temperatur der expiratorischen Luft gemessen und im Mittel Werte von 34,53° C mit Schwankungen im Bereich von 32,41 bis 35,69° C erhalten. Die Vitalkapazität betrug bei den gleichen Personen im Mittel 4038 ml mit Schwankungen im Bereich von 1825 bis 6550 ml, das Maximum des ausgeatmeten Luftvolumens lag nach normalem Einatmen bei 2730 ml im Mittel bei Schwankungen von 1180 bis 4550 ml. Es konnte festgestellt werden, daß ca. 65 bis 70% der gesamten ausgeatmeten Luft verworfen werden muß, bevor echte Alveolarluft vorliegt, bzw. ein konstanter Atemalkoholwert erhalten wird. Die CO2-Konzentration der Alveolarluft lag bei 3,5–8,3% (v/v), im Mittel bei 6,52%, getestet an 155 Versuchspersonen.Nach oraler Alkoholaufnahme war der noch in den Mundschleimhäuten verbliebene Alkohol nach 11 Minuten ohne besondere Mundspülung verschwunden, hingegen nach 8 Minuten, wenn die Mundhöhle mit Wasser gespült wurde. Die Wasserkondensation in den Mundstücken aus Plastikmaterial, durch die die Atemluft in das Prüfgerät eingeblasen wurde, zeigte eine Abhängigkeit von der Temperatur des Mundstücks : bei 3°C kondensierten im Mittel 13,0 mg, bei 22,5°C 8,6 mg und bei 34,7°C 4,6 mg Wasser.

Utilizing the Urinary 5-HTOL/5-HIAA Ratio to Determine Ethanol Origin in Civil Aviation Accident Victims

Specimens from fatal aviation accident victims are submitted to the FAA Civil Aerospace Medical Institute for toxicological analysis. During toxicological evaluations, ethanol analysis is performed on all cases. Care must be taken when interpreting a positive ethanol result due to the potential for postmortem ethanol formation. Several indicators of postmortem ethanol formation exist; however, none are completely reliable. The consumption of ethanol has been shown to alter the concentration of two major serotonin metabolites, 5-hydroxytryptophol (5-HTOL) and 5-hydroxyindole-3-acetic acid (5-HIAA). While the 5-HTOL/5-HIAA ratio is normally very low, previous studies using living subjects have demonstrated that the urinary 5-HTOL/5-HIAA ratio is significantly elevated for 11-19 h after acute ethanol ingestion. Recently, our laboratory developed and validated an analytical method for the simultaneous determination of both 5-HTOL and 5-HIAA in forensic urine samples using a simple liquid/liquid extraction and LC/MS/MS and LC/MS/MS/MS. In this previous work a 15 pmol/nmol serotonin metabolite ratio cutoff was established in postmortem urine, below which it could be conclusively determined that no recent antemortem ethanol consumption had occurred. In the current study this newly validated analytical method was applied to five ethanol-positive aviation fatalities where the origin of the ethanol present could not previously be conclusively determined. In four of the five cases examined the detected ethanol was demonstrated to be present due to postmortem microbial formation, and not consumption, even though some indication of ethanol consumption may have been present.

DOSE-RELATED HEART-RATE, PERCEPTUAL, AND DECISIONAL CHANGES IN MAN FOLLOWING MARIHUANA SMOKING

Information processing was tested in 12 male subjects after smoking marihuana containing 0, 10, or 20 mg. of delta-9-tetrahydrocannabinol (THC) in three consecutive experimental sessions according to a Latin square protocol. Successful dose control was indicated both by the dose-related linear increase observed in heart rate and by preliminary assays of THC metabolites excreted in the urine. During tachistoscopic presentation of varying numbers of circles, statistically significant decrements in information processing occurred as a function of THC dosage. However, adding irrelevant information (triangles) to the display of circles eliminated effects of marihuana on accuracy of counting. Complex reaction times for oddity discrimination increased significantly only after the high dose. Nonetheless, both the social and high doses inappropriately inhibited the general tendency to respond to changing stimuli during oddity discrimination. Marihuana had no effect on field-dependence as measured by the Rod-and-frame test.

Drugs and alcohol in civil aviation accident pilot fatalities from 2004-2008.

INTRODUCTION The Federal Aviation Administration (FAA) Office of Aerospace Medicine sets medical standards needed to protect the public and pilots from death or injury due to incapacitation of the pilot. As a part of this process, toxicology testing is performed by the FAA on almost every pilot who is fatally injured in an aviation accident to determine the medical condition of the pilot, medications used by the pilot at the time of the accident, and the extent of impairment, if any. METHOD The data were extracted from the FAA toxicology database for all pilots who died from 2004 to 2008 in aviation accidents. RESULTS The laboratory received and tested specimens from 1353 pilots who died in aviation accidents between 2004 and 2008; 507 of these pilots were found to be taking drugs and 92 had ethanol in excess of 0.04 g x dl(-1). DISCUSSION This study was conducted to determine the extent of drug use in pilots who have died in aviation accidents from 2004 to 2008 and to determine the types of drugs most commonly found. A comparison of previously published reports with this studys report was made to determine trends in drug use by pilots who have died in aviation accidents over the past 20 yr. Factors were discussed that could influence drug trends. Diphenhydramine, an H1 antihistamine with impairing properties, is the most commonly found drug in pilots who died in an aviation accident.

A new equation for calculating the maximum wait time for pilots who use an impairing medication

INTRODUCTION Pilots who use an impairing medication to treat a medical condition are required to wait an appropriate amount of time after completing the treatment before returning to duty. However, toxicology findings from fatal aviation accidents indicate not all pilots wait a sufficient period of time. Methods used today do not take into consideration the time required for the drug to reach subtherapeutic concentrations. METHODS An equation was developed based on the therapeutic range and the maximum expected half-life of the medication to objectively calculate a safe return-to-duty time for pilots. The new equation assumes the treating physician will not dose the patient beyond the upper therapeutic range of the medication and the person taking the medication has the maximum half-life reported in the literature. The equation N ln(0.5*Cmin/Cmax)/ln(0.5) was developed to determine the number of half-lives (n) required to reach one-half of Cmin, where Cmin = lower therapeutic concentration and Cmax = upper therapeutic concentration. Anonymous subjects were recruited under an approved IRB protocol. Blood and plasma were collected at approximately Cmax (2-3 h) and again after waiting approximately another 5 h. Toxicological analysis was performed on the specimens collected. RESULTS One subject taking a 25-mg dose had a 0.033 ug x ml(-1) blood concentration after waiting 8 h, well above the 0.025 ug x ml(-1) reported as impairing concentration. The new equation estimated a mean wait time for the 18 medications composed of 4 half-lives. DISCUSSION The new CAMI equation takes into consideration safety without grossly over estimating pilot wait times.