The Accuracy of Handheld Pre‐Arrest Breath Test Instruments as a Predictor of the Evidential Breath Alcohol Test Results

Drunk driving is a serious threat to public safety. All available and appropriate tools for curbing this threat should be employed to their full extent. The handheld pre‐arrest breath test instrument (PBT) is one tool for identifying the alcohol‐impaired driver and enforcing drunk driving legislation. A set of data was evaluated (n = 1779) where the PBT instrument was employed in drunk driving arrests to develop a multivariate predictive model. When maintained and operated by trained personnel, the PBT provides a reasonable estimate of the evidential test result within the relevant forensic range (95% prediction interval:  ± 0.003 g/210 L). ROC analysis shows that a multivariate model for PBT prediction of the evidentiary alcohol concentration above versus below the legal limit of 0.08 g/210 L has excellent performance with an AUC of 0.96. These results would be of value in evidential hearings seeking to admit the PBT results in drunk driving trials.     

The Effect of Alcohol‐Based Hand Sanitizer Vapors on Evidential Breath Alcohol Test Results

This study was undertaken to determine if the application of alcohol‐based hand sanitizers (ABHSs) to the hands of a breath test operator will affect the results obtained on evidential breath alcohol instruments (EBTs). This study obtained breath samples on three different EBTs immediately after application of either gel or foam ABHS to the operator's hands. A small, but significant, number of initial analyses (13 of 130, 10%) resulted in positive breath alcohol concentrations, while 41 samples (31.5%) resulted in a status code. These status codes were caused by ethanol vapors either in the room air or their inhalation by the subject, thereby causing a mouth alcohol effect. Replicate subject samples did not yield any consecutive positive numeric results. As ABHS application can cause a transitory mouth alcohol effect via inhalation of ABHS vapors, EBT operators should forego the use of ABHS in the 15 min preceding subject testing.     

The Measurand Problem in Breath Alcohol Testing

Proper interpretation of forensic measurements can be critical to the administration of justice. Breath alcohol testing is commonly relied upon to measure the concentration of alcohol in breath or, indirectly, in blood. The concentration sought constitutes the “quantity intended to be measured,” referred to as the measurand. Although breath tests always probe the same physical quantity, their measurand is dictated by statute and varies between jurisdictions. Thus, identical numerical values obtained from tests in disparate jurisdictions may refer to different quantities and may not indicate the relevant statutory measurand. This can lead to misinterpretation of results, referred to as the “measurand problem.” We first illustrate the concept of the measurand. Thereafter, the measurand problem is illustrated through application of Hlastala's breath test paradigm and Gullberg's work on breath test uncertainty. It is shown that where the measurand is not properly accounted for, conclusions based upon breath test evidence are undermined.     

The Effects of Gastroesophageal Reflux Disease on Forensic Breath Alcohol Testing

Fifteen test subjects, 10 of whom were diagnosed with gastroesophageal reflux disease (GERD), were dosed with alcohol to BACs above 0.150 g/dL. Blood and breath assays taken at 20-min intervals for 8 h after dosing demonstrated close agreement between postabsorptive BAC and BrAC values. Three subjects exhibited elevated breath alcohol concentrations up to 0.105 g/dL during the absorptive phase that were apparently due to the passage of gastric alcohol through the lower esophageal sphincter not attributable to eruction or regurgitation. The effect of gastric alcohol was not consistently proportional to the amount of unabsorbed gastric alcohol. Absorption of alcohol in the esophagus explains the nonproportionality. Breath samples contaminated by GERD-related alcohol leakage from the stomach into a breath sample were found only when there was a high concentration of alcohol in the stomach. When contaminated breath samples were encountered, they were irreproducible in magnitude.     

Effects of Homeopathic Mother Tinctures on Breath Alcohol Testing

In some countries, it is illegal to drive with any detectable amount of alcohol in blood; in others, the legal limit is 0.5 g/L or lower. Recently, some defendants charged with driving under the influence of alcohol and have claimed that positive breath alcohol test results were due to the ingestion of homeopathic mother tinctures. These preparations are obtained by maceration, digestion, infusion, or decoction of herbal material in hydroalcoholic solvent. A series of tests were conducted to evaluate the alcoholic content of three homeopathic mother tinctures and their ability to produce inaccurate breath alcohol results. Nine of 30 subjects gave positive results (0.11–0.82 g/L) when tests were taken within 1 min after drinking mother tincture. All tests taken at least 15 min after the mother tincture consumption and resulted in alcohol-free readings. An observation period of 15–20 min prior to breath alcohol testing eliminates the possibility of false-positive results.     

Variability in the Blood/Breath Alcohol Ratio and Implications for Evidentiary Purposes

The breath analyzer is an indispensable tool for identifying alcohol levels among drivers. While numerous studies have shown high correlations between blood and breath alcohol concentrations, most are limited by the study design. This study seeks to assess this relationship by minimizing potential measurement bias, document time from alcohol consumption to testing, and adjusting for potential confounders. A blinded study was performed using conditions closely resembling those in the field. The Draeger 7110 MKIII IL breath analyzer was used to assess breath alcohol concentrations (BrAC). Participants were 61 healthy volunteers aged 21–37 years with body mass index ≤30 and no history of alcoholism. A total of 242 valid blood/breath tests were performed in four test sets. The study results showed a high correlation coefficient between BrAC and blood alcohol concentration (BAC) levels (r = 0.983) with high sensitivity (97%) and specificity (93%). This strong association between the breath analyzer and BAC persisted even after adjustment for various stages of alcohol absorption. These results illustrate the high diagnostic sensitivity of the breath analyzer in field‐tested conditions.     

Evaluation of the Analytical Performance of a Fuel Cell Breath Alcohol Testing Instrument: A Seven‐Year Comprehensive Study

Abstract: Between 2003 and 2009, 54,255 breath test sequences were performed on 129 AlcoSensor IV–XL evidential instruments in Orange County, CA. The overall mean breath alcohol concentration and standard deviation from these tests was 0.141 ± 0.051 g/210 L. Of these test sequences, 38,580 successfully resulted in two valid breath alcohol results, with 97.5% of these results agreeing within ±0.020 g/210 L of each other and 86.3% within ±0.010 g/210 L. The mean absolute difference between duplicate tests was 0.006 g/210 L with a median of 0.004 g/210 L. Of the 2.5% of duplicate test results that did not agree within ±0.020 g/210 L, 95% of these had a breath alcohol concentration of 0.10 g/210 L or greater and 77% had an alcohol concentration of 0.15 g/210 L or greater. The data indicate that the AlcoSensor IV–XL can measure a breath sample for alcohol concentration with adequate precision even amid the effects of biological variations.     

Proficiency Testing as a Basis for Estimating Uncertainty of Measurement: Application to Forensic Alcohol and Toxicology Quantitations

Abstract: While forensic laboratories will soon be required to estimate uncertainties of measurement for those quantitations reported to the end users of the information, the procedures for estimating this have been little discussed in the forensic literature. This article illustrates how proficiency test results provide the basis for estimating uncertainties in three instances: (i) For breath alcohol analyzers the interlaboratory precision is taken as a direct measure of uncertainty. This approach applies when the number of proficiency tests is small. (ii) For blood alcohol, the uncertainty is calculated from the differences between the laboratory’s proficiency testing results and the mean quantitations determined by the participants; this approach applies when the laboratory has participated in a large number of tests. (iii) For toxicology, either of these approaches is useful for estimating comparability between laboratories, but not for estimating absolute accuracy. It is seen that data from proficiency tests enable estimates of uncertainty that are empirical, simple, thorough, and applicable to a wide range of concentrations.     

A Review of Alcohol‐Impaired Driving: The Role of Blood Alcohol Concentration and Complexity of the Driving Task

The operation of a motor vehicle requires the integrity of sensory, motor, and intellectual faculties. Impairment of these faculties following the consumption of alcohol has been studied extensively through laboratory, closed‐course and on‐road driving, and epidemiological studies. The scientific literature was reviewed critically, with a focus on low‐to‐moderate blood alcohol concentrations (BAC ≤ 0.100%), to identify the most reliable determinants of alcohol‐impaired driving. Variables such as age, gender, driving skill, and tolerance were shown to have limited impact on impairment. It was concluded the most relevant variables are BAC and complexity of the driving task. The scientific literature provides a high degree of confidence to support the conclusion that a BAC of 0.050% impairs faculties required in the operation of a motor vehicle. Whether impairment is apparent depends upon the complexity of the driving task, which applies to both study design and actual driving.     

Survival of Very High Blood Alcohol Concentration Without Consequential Damage in a Patient Without a Previous Substance Use Disorder

Intoxications with alcohol may lead to death depending on (maximum) blood alcohol concentration (BAC) and accompanying factors such as liver function, tolerance, and comedication. Death may occur due to ethanol‐induced respiratory depression and/or aspiration of gastric content (due to an impaired gag reflex); thus, securing of the airway and ventilation is occasionally necessary. A case of a 58‐year‐old female patient with depression who demonstrated a very high BAC of 8.68 gm/L (0.868%) following ingestion of large amounts of alcohol with suicidal intent is presented. Intubation and ventilation were life‐saving, and the patient did not develop any physical or consequential damage. As the patient had not regularly used alcohol or any other psychotropic agent, tolerance could be ruled out. This case emphasizes the necessity of rapid securing of the airway in patients with alcohol intoxication and respiratory depression and, furthermore, illustrates the large interindividual differences regarding ethanol susceptibility.     

Test of an alternative method for determining sex from the os coxae: applications for modern Americans

A recently proposed method for determining sex from the os coxae reports a 98% success rate using European collections. The purposes of the present study are to (1) evaluate the success rate of this proposed method using modern American os coxae from different population subgroups; (2) compare the success rate of the new method with that obtained using traditional techniques; and (3) determine replicability of the new method and interobserver error. Eight hundred and seventy-six adult left os coxae were independently evaluated by both authors. Summary statistics for sex classifications were calculated for the total sample and for a random sample of 400 individuals. The impact of sex and ancestry on the success of each method was calculated on the random sample using Pearson's chi2 values. Results demonstrate that for modern American os coxae, neither sex nor race have a significant impact on the success rate for either the new or traditional methods (p < 0.01). Additionally, the success rate of the new method is comparable with that obtained using traditional techniques. Finally, interobserver error using the new method for overall sex determination is low.     

Alcohol intoxication may exacerbate the effects of blunt cranial trauma through changes in brain free magnesium levels

Moderate to high levels of alcohol decrease brain intracellular free magnesium concentration, a factor known to be critical in brain injury. Phosphorus magnetic resonance spectroscopy was used to examine changes to brain free magnesium concentration after blunt cranial trauma in alcohol-intoxicated rats. Rats exposed acutely or chronically to alcohol sufficient to increase blood alcohol levels to between 150 and 350 mg/dL demonstrated a brain free magnesium level that was 20-50% less than in nonintoxicated animals (p < 0.01). After injury, brain free magnesium levels declined more rapidly and to a greater extent in alcohol-affected animals than in nonintoxicated control animals (p < 0.001). As both preinjury depletion of magnesium and degree of magnesium decline after brain injury have been associated with poor recovery, these findings suggest that moderate to severe alcohol intoxication may predispose the brain to a worse outcome by reducing brain free magnesium levels, both before and after injury.     

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 large-scale study of the relationship between blood and breath alcohol concentrations in New Zealand drinking drivers

Blood alcohol concentrations (BAC) and corresponding breath alcohol concentrations (BrAC) were determined for 21,582 drivers apprehended by New Zealand police. BAC was measured using headspace gas chromatography, and BrAC was determined with Intoxilyzer 5000 or Seres Ethylometre infrared analysers. The delay (DEL) between breath testing and blood sampling ranged from 0.03 to 5.4 h. BAC/BrAC ratios were calculated before and after BAC values were corrected for DEL using 19 mg/dL/h as an estimate of the blood alcohol clearance rate. Calculations were performed for single and duplicate breath samples obtained using the Intoxilyzer (groups I-1 and I-2) and Seres devices (groups S-1 and S-2). Before correction for DEL, BAC/BrAC ratios for groups I-1, I-2, S-1, and S-2 were (mean+/-SD) 2320+/-260, 2180+/-242, 2330+/-276, and 2250+/-259, respectively. After BAC values were adjusted for DEL, BAC/BrAC ratios for these groups were (mean+/-SD) 2510+/-256, 2370+/-240, 2520+/-280, and 2440+/-260, respectively. Our results indicate that in New Zealand the mean BAC/BrAC ratio is 19-26% higher than the ratio of the respective legal limits (2000).     

Developmental Validation of RSID™-Saliva: A Lateral Flow Immunochromatographic Strip Test for the Forensic Detection of Saliva

Abstract:  Current methods for forensic identification of saliva generally assay for the enzymatic activity of α-amylase, an enzyme long associated with human saliva. Here, we describe the R apid S tain ID entification (RSID™-Saliva), a lateral flow immunochromatographic strip test that uses two antisalivary amylase monoclonal antibodies to detect the presence of salivary amylase, rather than the activity of the enzyme. We demonstrate that RSID™-Saliva is accurate, reproducible, and highly sensitive for human saliva; RSID™-Saliva detects less than 1 μL of saliva. The sensitivity of RSID^TM-Saliva allows investigators to sample a fraction of a questioned stain while retaining the majority for DNA-STR analysis. We demonstrate that RSID™-Saliva identifies saliva from a variety of materials (e.g., cans, bottles, envelopes, and cigarette-butts) and it does not cross-react with blood, semen, urine, or vaginal fluid. RSID™-Saliva is a useful forensic test for determining which evidentiary items contain saliva and thus may yield a DNA profile.     

A New Index for the MMPI‐2 Test for Detecting Dissimulation in Forensic Evaluations: A Pilot Study

This pilot study is the starting point of a potentially broad research project aimed at identifying new strategies for assessing malingering during forensic evaluations. The forensic group was comprised of 67 males who were seeking some sort of certification (e.g., adoption, child custody, driver's license, issuance of gun permits, etc.); the nonforensic group was comprised of 62 healthy male volunteers. Each participant was administered the MMPI‐2. Statistical analyses were conducted on obtained scores of 48 MMPI‐2 scales. In the first step, parametric statistics were adopted to identify the best combination of MMPI‐2 scales that differentiated the two groups of participants. In the second step, frequency‐based, nonparametric methods were used for diagnostic purposes. Results: A model that utilized the best three predictors (“7‐Pt”, “L,” and “1‐Hs”) was developed and used to calculate the Forensic Evaluation Dissimulation Index (FEDI), which features satisfactory diagnostic accuracy (0.9), sensitivity (0.82), specificity (0.81), and likelihood ratio indices (LR+ = 4.32; LR? = 0.22).     

An Improved Method for the Diatom Test Utilizing DNA Binding Ability of Silica

In order to devise a better forensic test for diatoms, the DNA binding ability of the diatom frustule constructing by silica, in the presence of chaotropic ions were utilized. It was proved that the diatoms were able to be captured via λDNA using silica‐coated magnetic beads (Mag beads), followed by isolation and purification from the Mag beads as a solid phase by substituting the chaotropic agent with ultrapure water. Five cases of drowning, three in freshwater and two in seawater, were applied to the present method and similar results as the usual diatom test were obtained. Specimens of lung and other organs were rendered clearly visible, with elimination of foreign impurities. The present method appears applicable for detection of diatoms indirectly using PCR amplification of bound DNA or directly staining of the DNA.     

Screening Test for Shed Skin Cells by Measuring the Ratio of Human DNA to Staphylococcus epidermidis DNA

A novel screening method for shed skin cells by detecting Staphylococcus epidermidis (S. epidermidis), which is a resident bacterium on skin, was developed. Staphylococcus epidermidis was detected using real‐time PCR. Staphylococcus epidermidis was detected in all 20 human skin surface samples. Although not present in blood and urine samples, S. epidermidis was detected in 6 of 20 saliva samples, and 5 of 18 semen samples. The ratio of human DNA to S. epidermidisDNA was significantly smaller in human skin surface samples than in saliva and semen samples in which S. epidermidis was detected. Therefore, although skin cells could not be identified by detecting only S. epidermidis, they could be distinguished by measuring the S. epidermidis to human DNA ratio. This method could be applied to casework touch samples, which suggests that it is useful for screening whether skin cells and human DNA are present on potential evidentiary touch samples.