Evidential Breath Testing Research Articles

Increased population drinking is not always associated with increased number of drink driving convictions

Increased population drinking is not always associated with increased number of drink driving convictions

Comparison of the Analytical Capabilities of the BAC Datamaster and Datamaster DMT Forensic Breath Testing Devices

The State of Michigan uses the Datamaster as an evidential breath testing device. The newest version, the DMT, will replace current instruments in the field as they are retired from service. The Michigan State Police conducted comparison studies to test the analytical properties of the new instrument and to evaluate its response to conditions commonly cited in court defenses. The effects of mouth alcohol, objects in the mouth, and radiofrequency interference on paired samples from drinking subjects were assessed on the DMT. The effects of sample duration and chemical interferents were assessed on both instruments, using drinking subjects and wet-bath simulators, respectively. Our testing shows that Datamaster and DMT results are essentially identical; the DMT gave accurate readings as compared with measurements made using simulators containing standard ethanol solutions and that the DMT did not give falsely elevated breath alcohol results from any of the influences tested.

A study to investigate the ability of subjects with chronic lung diseases to provide evidential breath samples using the Lion Intoxilyzer®6000 UK breath alcohol testing device

The Lion Intoximeter®3000 has been used for evidential breath testing in the U.K. for some years. Some individuals with lung diseases have difficulty in providing evidential breath samples using the device. This study describes an investigation that we have carried out on a newer instrument — the Lion Intoxilyzer®6000UK — which is now in use in the U.K. The study was designed to investigate the ability of subjects with a variety of lung diseases to provide evidential breath samples using this device. The 40 adult subjects investigated comprized 10 normal controls, 10 with asthma, 10 with chronic obstructive pulmonary disease (COPD) and 10 with restrictive lung disease. After baseline spirometry, subjects were given alcohol to drink, the quantity based upon body weight. After a gap of at least 20 min, subjects were asked to provide evidential breath samples in accordance with the test procedure built into the Lion Intoxilyzer 6000UK. The results showed that two asthmatic subjects, four with COPD and three with restrictive lung disease failed to provide evidential breath samples even after four attempts. Despite the device requiring a minimum sample volume of 1·2 l, eight of the nine subjects who failed had a forced vital capacity (FVC) of more than 1·5 l. Seven of these nine subjects had a forced expiratory volume in 1 sec (FEV1) of less than 1·0 l. In conclusion, this study has shown that some subjects with lung diseases may have difficulty in providing evidential breath samples using the Lion Intoxilyzer 6000 UK.

Field Evaluation of the PAS III Passive Alcohol Sensor

Passive alcohol sensors (PAS) are screening devices designed to sample nonintrusively the ambient air around a driver's mouth to determine the presence of alcohol. Studies have shown that PAS devices can aid police officers in the identification of unpaired drivers, particularly at sobriety checkpoints. Data from a 1996 nationwide survey, in which 5,392 drivers were evaluated for alcohol using both the PAS III (a passive sensor housed in a flashlight) and evidential breath test devices, have allowed the determination of appropriate criteria at various blood alcohol concentrations (BAC) for detecting impaired drivers in the field. Using the appropriate criteria, the PAS III can identify about 75% of the drivers with BACs at or above 0.10%, and 70% at or above 0.08%. This is a vast improvement over the 40-50% detection rate currently achieved by police officers at checkpoints not using sensors. Using the PAS III few drivers would be identified inappropriately. At the criterion recommended for detecting BACs at or above 0.08%, about 14% of drivers with BACs of 0.02-0.05% would be incorrectly identified as having a higher BAC. Field studies have shown that when police officers rely on observation alone about 20% of drivers with low BACs are detained for further evaluation. More widespread use of passive sensors by police officers would aid in the detection of drinking drivers. Sensors also could provide an additional deterrent to the general public if they believe that when stopped by the police after drinking they will be detained for further evaluation.

Evaluation of the Effect of Asthma Inhalers and Nasal Decongestant Sprays on a Breath Alcohol Test

The effects of eight prescription and non-prescription asthma inhalers and four over-the-counter nasal decongestants on the DataMaster, an evidential breath alcohol instrument, were evaluated. Subjects self administered the medication, and breath alcohol tests were administered immediately after use and following a 15 min waiting period. The only preparation which produced any effect on the instrument was Primatene Mist which contains 34% ethyl alcohol. The alcohol was, however, eliminated from the breath in the usual pattern of mouth alcohol elimination, and after 5 min there was no longer any effect. The inclusion of a 15 min deprivation period prior to an evidential breath test, during which time nothing is introduced into the mouth, is an adequate safeguard against interference with the test caused by alcohol containing inhalers.

The occupations of drink drivers: Using occupational information to identify targetable characteristics of offenders

Data collected by the Victoria Police at the time an alleged drink-driving offender undergoes an evidential breath test for the presence of alcohol were analyzed to investigate the possibility that occupational information could be used to define groups of drink-drivers with similar characteristics. Such groups could then be utilized in the development of targeted public education campaigns in the Victorian (Australia) context where there are already high levels of enforcement and mass-media publicity. It is argued that drink-drivers in this context are likely to share some characteristics which might reduce the impact of current programs. Analysis of the data relied on the application of a theory of the relationship between career choice and other behavioral characteristics (Holland, 1973, Making Vocational Choices, Prentice Hall, Englewood Cliffs, N.J.; Holland, 1975, Manual for the Vocational Preference Inventory, Consulting Psychologists Press, Palo Alto, CA). The analysis identified two potential groups which accounted for 58% of the male drink-drivers. These groups differed from other male drink drivers in a number of ways, underlining the potential for their use as targets in future campaigns. One occupational category accounted for 42% of the male drink drivers, including occupations such as carpenter, electrician, chef, mechanic, gardener, and laborer. The behavioral characteristics associated with these occupational codes in the Holland model included asocial, conforming, reserved, introspective, unpopular, orderly, careful, unimaginative, and defensive. The other occupational category accounted for 16% of the male drink drivers and included occupations such as business manager, company director, public servant, and sales representative. Behavioral characteristics associated with this combination included acquisitive, adventurous, ambitious, energetic, extroverted, friendly, and generous.

Volatile substances and their potential to interfere with breath alcohol reading instruments

Two cases are presented which highlight the potential for abused volatile substances to interfere with the results of evidential breath testing equipment. Home Office guidance, issued in 1983, advises that breath testing devices should not be used when a driver is suspected of glue-sniffling, but the advice does not appear to be widely known. The implications for both police officers and police surgeons are discussed. New evidential breath testing devices, which are planned to be introduced into the UK in the first half of 1997, are designed to recognize interfering substances such as solvents. The potential problems these new devices may pose are considered.

Interfering substances identified in the breath of drinking drivers with Intoxilyzer 5000S.

The selectivity of analytical methods used to determine ethanol in body fluids has always been an important concern in connection with chemical testing for intoxication. Allegations of false high breath-alcohol readings obtained because of the presence of volatile organic compounds (VOCs) other than ethanol is a well-known defense argument in trials concerning driving under the influence of alcohol (DUI). However, not much information exists to substantiate this claim, especially when modern analytical technology such as multiple wavelength infrared breath-alcohol instruments is used for forensic purposes. Whenever breath tests were aborted because interfering substances were ostensibly detected during routine evidential breath-alcohol analysis in Sweden with the Intoxilyzer 5000S, a sample of venous blood was taken for analysis by headspace gas chromatography. Most of the aborted breath tests could be explained by abnormally high concentrations of acetone, isopropanol, or methyl ethyl ketone in the samples analyzed. These VOCs originate in blood and breath after DUI suspects consume denatured alcohol preparations containing these solvents. However, the intoxilyzer 5000S sometimes aborted the evidential breath test even though VOCs other than ethanol were not identified in the blood samples. The reason for these latter tests being aborted is hard to understand because the blood-breath ratios of ethanol were within the range expected (1900:1 to 2800:1) for a large number of other DUI suspects tested with Intoxilyzer 5000S under the same conditions when interfering substances were not detected.

Department of Transportation 1995 Regulations for Alcohol Testing

1. The Omnibus Employees Testing Act of 1991 (part of the Department of Transportation and Related Agencies Act of 1992) mandated rules and regulations on drug and alcohol testing for employees in "safety sensitive" positions. 2. Employees in "safety sensitive" positions who misuse alcohol jeopardize themselves and others. As a noninvasive, relatively quick method for testing alcohol misuse. Evidential Breath Testing allows an employer to test, and if the results are positive, to immediately remove an employee from a "safety sensitive" position. 3. Occupational health nurses play an important role in the commercial drivers' license screening process; therefore, they can assist employers' understanding of and compliance with these federally mandated regulations.

Biotransformation of Acetone to Isopropanol Observed in a Motorist Involved in a Sobriety Check

We report the identification of acetone (0.45 mg/mL) and isopropanol (0.17 mg/mL) but without the presence of ethanol in a blood sample from a man suspected of driving under the influence of alcohol. A preliminary breath screening test with an electrochemical instrument (Alcolmeter S-L2) was positive and an evidential breath-test with a dual wavelength infrared analyzer (Intoxilyzer 5000), recognized the presence of an interferant in the subject's breath. The man admitted drinking moderate amounts of alcohol (vodka) the previous evening and was being treated by his doctor for hyperglycemia by special dietary control. This case scenario provides a good example of severe metabolic ketoacidosis in an ostensibly healthy man driving on the highway. Biotransformation of the abnormally high concentration of blood-acetone to isopropanol occurs through the alcohol dehydrogenase pathway.

A connectionist approach to fuel cell sensor array processing for gas discrimination

Fuel cell sensors are in widespread use throughout the world, applied primarily in the areas of evidential breath testing and environmental monitoring. A problem which affects the adoption of such transducers however lies in their specificity. Although the fuel cell does have some inherent specificity it will, for example in the case of breath alcohol measurements, also respond to other alcohols and aldehydes if they have a significant presence in the test sample. This paper presents methods which improve transducer specificity through the incorporation of discrimination algorithms based on artificial neural networks. The use of such algorithms in conjunction with a single cell has facilitated the detection of the presence of contaminants in a sample (for example methanol in ethanol) at levels as low as 5% and also allows the identification of a single pure gas from a set of known gases. The results obtained are improved however when neural networks are used in conjunction with an array of sensors where each cell in the array is operated under different conditions. Exploitation of the non-linear temperature effects exhibited by an array of cells eases the task of the network and facilitates improved performance. The paper compares both supervised and unsupervised network paradigms together with a range of signal pre-processing techniques applied to both single and multiple cell systems.

Differences between roadside and subsequent evidential breath alcohol results and their forensic significance.

Breath alcohol measurements for forensic purposes are typically not made at the time of a driving incident but at some later time. Therefore, the magnitude of variation in breath alcohol concentration (BrAC) following the time of arrest is of concern. The use of roadside preliminary breath test (PBT) instruments can provide data on BrAC closer to the time of a driving incident and allow for comparison with later evidential analysis. This retrospective study evaluates two distributions (N = 968): differences between PBT results and the first evidential breath test (PBT-BrAC1) and differences between two (duplicate) evidential breath alcohol tests (BrAC1-BrAC2). The two distributions were shown to vary from each other and from the normal with statistical significance (p less than .05). The PBT-BrAC1 distribution had greater variability (SD = .025) than the BrAC1-BrAC2 distribution (SD = .010). An important result was that the PBT was equal to (within duplicate sampling variability) or greater than BrAC1 in approximately 85.5% of the cases. The remaining 14.5% could not be explained by sampling variability within the duplicate test distribution. The variability in both distributions typically exceeds the normally accepted alcohol elimination rates. The conclusion is that differences between roadside and subsequent evidential breath results cannot be attributed solely to absorption or elimination kinetics. Intra-individual breath sample differences can be large and thus obscure the accurate evaluation of absorption and elimination rates. Breath tests conducted within approximately 2 hours of driving will reflect, within experimental uncertainty, the BrAC at the time of driving.

Local Dental Anaesthesia and Evidential Breath Testing: The Effect of Injection of Local Anaesthetic on Lip Seal

The effect of local anaesthetic infiltration on the ability of subjects to provide adequate specimens of breath for analysis using an evidential breath testing device was assessed. The results showed that in ten out of the fourteen cases there was no impairment of the ability to provide the specimens of breath at any time. Within two hours of the administration of a local anaesthetic all subjects were able to provide the requisite samples.

The laboratory testing of evidential breath-testing (EBT) machines

Six types of evidential breath testing (EBT) machines were tested in a laboratory. The testing experiments are classified into three paragraphs: analytical performance, sampling and operating conditions. In order to characterize the analytical performance a set of parameters (repeatability, reproducibility, linearity, accuracy, specificity) was established. The results were, in general, good, although an underestimation of the actual vapour concentration was observed. Different types of EBT machines showed significant differences measuring the same vapour.

Measuring alcohol intoxication: the development, reliability and validity of an observational instrument.

This study presents an observational instrument designed to assess the presence or absence of alcohol intoxication as well as the level of intoxication. The Alcohol Symptom Checklist (ASC) was validated by comparing the blood alcohol level (BAL) of 672 subjects with the ASC score. The correlation between BAL and ASC for the final version of the scale was .84; alpha reliability = .92; interrater reliability = .93; and mean interitem correlation = .51. These results confirm the scale's reliability, its interrater consistency and its predictive validity. This instrument may be used in place of BAL measures in situations where it would be impractical to obtain samples of blood or alveolar air. The ASC will facilitate naturalistic studies of drinking behavior which previously have been limited by the lack of an unobtrusive method for assessing symptoms of intoxication. In addition, it has potential for use by law enforcement officials in situations where persons suspected of driving while intoxicated refuse to take an evidential breath test. This article examines requirements for training in the use of the ASC, and discusses other potential uses of the instrument.