Publications

As with any research and development effort, the DADSS Research Program has published findings throughout the process. In the links below, you can access these articles and research papers, published from 2009 through the present.

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Comparison of spectroscopically measured finger and forearm tissue ethanol concentration to blood and breath ethanol measurements

US National Library of Medicine, National Institutes of Health
Publication Year: 2011

Previous works investigated a spectroscopic technique that offered a promising alternative to blood and breath assays for determining in vivo alcohol concentration. Although these prior works measured the dorsal forearm, we report the results of a 26-subject clinical study designed to evaluate the spectroscopic technique at a finger measurement site through comparison to contemporaneous forearm spectroscopic, venous blood, and breath measurements. Through both Monte Carlo simulation and experimental data, it is shown that tissue optical probe design has a substantial impact on the effective path-length of photons through the skin and the signal-to-noise ratio of the spectroscopic measurements. Comparison of the breath, blood, and tissue assays demonstrated significant differences in alcohol concentration that are attributable to both assay accuracy and alcohol pharmacokinetics. Similar to past works, a first order kinetic model is used to estimate the fraction of concentration variance explained by alcohol pharmacokinetics (72.6-86.7%). A significant outcome of this work was significantly improved pharmacokinetic agreement with breath (arterial) alcohol of the finger measurement (mean k(Art-Fin) = 0.111 min(-1)) relative to the forearm measurement (mean k(Art-For) = 0.019 min(-1)) that is likely due to the increased blood perfusion of the finger.

Driver Alcohol Detection System for Safety DADSS

Transportation Research Board 90th Annual Meeting.
Publication Year: 2011

Driver Alcohol Detection System for Safety (DADSS). Background and Rationale for Technology Approaches

Society of Automotive Engineers Technical Paper, Paper No. 2010–01–1580, Warrendale, PA: Society of Automotive Engineers.
Publication Year: 2010

The Automotive Coalition for Traffic Safety (ACTS) and the National Highway Traffic Safety Administration (NHTSA) have commenced a five-year cooperative agreement exploring the feasibility of, and the public policy challenges associated with, widespread use of in-vehicle alcohol detection technology to prevent alcohol-impaired driving. This effort, known as the Driver Alcohol Detection System for Safety (DADSS) program, aims to develop technologies that could be a component of a system to prevent the vehicle from being driven when the device registers that the driver’s blood alcohol concentration (BAC) exceeds the legal limit (currently 0.08 g/dL throughout the United States). For DADSS installation as original equipment in new vehicles there are critical requirements to be met. Alcohol detection technology must be seamless to the driver and be able to quickly and accurately measure the driver’s BAC non-invasively. DADSS devices must be compatible for mass-production at a moderate price, be durable, meet high levels of reliability, and require little or no maintenance. Potential technological approaches have been identified and thorough analyses undertaken to determine candidates for further development, utilizing a clear understanding of the processes by which alcohol is absorbed into the blood stream, distributed within the body, and eliminated from it. This paper describes what is known regarding alcohol measurement via various methods, and details which technologies deserve further study. Two approaches are identified that have considerable promise in measuring driver BAC non-invasively within the time and accuracy constraints: 1) Tissue Spectrometry, a touch-based approach allowing estimation of alcohol in tissue through detection of light absorption at a particular wavelength from a beam of near-infrared light reflected from within the subject’s tissue, 2) Distant Spectrometry using part of the infrared light spectrum where the light is transmitted toward the subject from a source that receives and analyses the reflected and absorbed spectrum, thereby allowing assessment of alcohol concentration in the subject’s exhaled breath.

Breath Analyzer for Alcolocks and Screening Devices

IEEE
Publication Year: 2010

Alcolocks and alcohol screening devices are becoming commonplace, and their use is expected to grow rapidly with cost reduction and improved usability. A new breath analyzer prototype is demonstrated, with the prospects of eliminating the mouthpiece, reducing expiration time and volume, improving long-term stability, and reducing life cycle cost. Simultaneous CO2 measurements compensate for the sample dilution and unsaturated expiration. Infrared transmission spectroscopy is used for both the alcohol and CO2 measurement, yet the entire system is contained within a small handheld unit. Experimental results are reported on the device sensitivity, linearity, resolution, and influence from varying measuring distance. The correlation between early and full-time sampling was established in 60 subjects. Basic concept verification was obtained, whereas resolution and selectivity still needs to be improved. Further improvements are expected by system optimization and integration.

Improved Breath Alcohol Analysis with Use of Carbon Dioxide as the Tracer Gas

Mälardalen University Press Dissertations
Publication Year: 2010

State-of-the-art breath analysers require a prolonged expiration into a mouthpiece to obtain the accuracy required for evidential testing and screening of the alcohol concentration. This requirement is unsuitable for breath analysers used as alcolock owing to their frequent use and the fact that the majority of users are sober drivers; as well as for breath testing in uncooperative persons.

This thesis presents a method by which breath alcohol analysis can be improved, using carbon dioxide (CO2) as the tracer gas, offering quality control of the breath sample, enabling the mouthpiece to be eliminated, and bringing about a significant reduction in the time and effort required for a breath alcohol screening test. With simultaneous measurement of the ethanol and the CO2 concentrations in the expired breath, the end-expiratory breath alcohol concentration (BrAC) can be estimated from an early measurement, without risk of underestimation.

Comparison of CO2 and water as possible tracer gases has shown that the larger intra- and interindividual variations in the (end-expiratory) concentration is a drawback for CO2 whereas the advantages are a low risk of underestimation of the BrAC, and the limited influence from ambient conditions on the measured CO2 concentration. The latter is considered to be of importance because the applications likely imply that the breath tests will be conducted in an uncontrolled environment, e.g., in a vehicle or ambulance. In emergency care, the measurement of the expired CO2 concentration also provides the physicians with information about the patient’s respiratory function.

My hope and belief, is that with a more simple, reliable and, user-friendly test procedure, enabled with the simultaneous measurement of the CO2 in the breath sample, the screening for breath alcohol will increase. An increased number of breath alcohol analysers installed as alcolocks and more breath alcohol tests conducted in emergency care, is likely to save lives and diminish the number and severity of injuries.