Origin of the First Handheld Breath Alcohol Analyzer Incorporating an Electrochemical Sensor.

Historical events leading to the development of the first handheld instrument for breath alcohol analysis using an electrochemical sensor are reviewed. The first prototype instrument, known as the Alcolmeter Pocket Model, became available in 1972 and weighed only 180 g and was about the size of a cellphone. By the mid-1970s, the Alcolmeter instrument was used by police forces in several countries as a preliminary roadside test of driver sobriety. Positive results in a roadside breath test were considered sufficient evidence to arrest a suspect for further evaluation and testing. This might entail an evidential-quality breath alcohol test or taking a sample of the driver's blood for analysis at a forensic laboratory. The main advantages of breath testing over blood testing are the non-invasive nature of the sampling procedure compared with sticking a needle in a vein to draw blood, and obtaining immediate information whether or not a person is in breach of the drunk driving legislation.

Total body water is the preferred method to use in forensic blood-alcohol calculations rather than ethanol's volume of distribution.

During the prosecution and defence of drink-driving cases, forensic practitioners are often required to engage in various blood-alcohol calculations, such as whether or not the statutory limit was exceeded (e.g. 80mg/100mL, 0.08g/100mL or 0.80g/L). For this purpose, most forensic scientists utilize the Widmark equation, or some modification thereof, to calculate a person's blood alcohol concentration (BAC) based on information about the amount of ethanol consumed and the pattern of drinking. This equation comes in two main forms; one of which incorporates the apparent volume of distribution of ethanol (V) and the other a person's total body water (TBW). In this study, we utilised two independent data sets, one involving the determination of V for ethanol in 173 men and 63 women, and the other TBW determined for 582 men and 884 women. Those subjects included in the TBW group represented various racial groups (Caucasians, African Americans, Hispanics, Asians and Puerto Ricans), with body mass index (BMI) ranging from 17 to 80kg/m2. Both versions of the Widmark equation were evaluated in relation to their accuracy and precision in predicting TBW and/or V using the two most common anthropometric equations; those of Watson et al. and Forrest. Both anthropometric equations exhibited good accuracy (<4.3%) for the prediction of both TBW and V. However, the root mean square error was lower TBW was used for prediction (9.09-12.84%) rather than V (11.72-15.08%). Overall, this study has demonstrated (a) that blood-alcohol calculations are more reliable using TBW rather than V (b) that both equations (Watson et al. and Forrest) are applicable to ethnic groups other than Caucasians and (c) the Forrest equation predicts TBW in men and women with BMI from 17 to 35kg/m2 and that the Watson et al. equation works for those with more extreme BMI; females (17-80kg/m2) and males (17-67kg/m2).

Evidence based survey of the distribution volume of ethanol: Comparison of empirically determined values with anthropometric measures.

The Widmark equation is commonly used when blood alcohol calculations are required in forensic and legal medicine, such as in road-traffic cases and alcohol-related deaths. An important biological variable in this connection is the volume of distribution (Vd) of ethanol, which is commonly referred to as the rho-factor. Although a person's Vd can be determined empirically through controlled drinking experiments, this approach is not very practical in reality. For this reason, a number of anthropometric equations have been developed that utilize sex, age, height and weight to estimate the person's total body water (TBW) and hence Vd of ethanol. To date, there are not any studies that compare Vd derived from anthropometric data with robust values measured empirically. From the literature we compiled information about the Vd of ethanol from drinking studies with 173 Caucasian males and 63 Caucasian females from Western Europe. These empirically derived values of Vd were then compared with estimates derived from various anthropometric equations. In males the Watson, Watson and Batt regression equation involving age, height and weight gave the most accurate results (bias was 0.00L/kg) and 95% range ±0.13L/kg. The equation derived by Forrest, which took into consideration a person's body mass index (BMI), gave the best estimates of Vd for females; mean bias -0.01L/kg and range ±0.15L/kg.

Comparison of breath-alcohol screening test results with venous blood alcohol concentration in suspected drunken drivers.

Hand-held electronic breath-alcohol analyzers are widely used by police authorities in their efforts to detect drunken drivers and to improve road-traffic safety. Over a three month period, the results of roadside breath-alcohol tests of drivers apprehended in Finland were compared with venous blood alcohol concentration (BAC). The mean (median) time between sampling blood and breath was 0.71h (0.58h) with a range from 0 to 6h. Some hand-held instruments gave results as the concentration of alcohol in breath and were converted into BAC assuming a blood-breath alcohol ratio (BBR) of 2260. The mean venous BAC (1.82g/kg) in traffic offenders was higher than the result predicted by the hand-held breath analyzers (1.72g/kg). In 1875 roadside tests, the relationship between venous BAC (x) and BrAC (y) was defined by the regression equation y=0.18+0.85x. The coefficients show both a constant bias (y-intercept 0.18g/kg) and a proportional bias (slope=0.85). The residual standard deviation (SD), an indicator of random variation, was ±0.40g/kg. After BAC results were corrected for the time elapsed between sampling blood and breath, the y-intercept decreased to 0.10g/kg and 0.004g/kg, respectively, when low (0.1g/kg/h) and high (0.25g/kg/h) rates of alcohol elimination were used. The proportional bias of 0.85 shows that the breath-alcohol test result reads lower than the actual BAC by 15% on average. This suggests that the BBR of 2260 used for calibration should be increased by about 15% to give closer agreement between BAC and BrAC. Because of the large random variation (SD±0.40g/kg), there is considerable uncertainty if and when results from the roadside screening test are used to estimate venous BAC. The roadside breath-alcohol screening instruments worked well for the purpose of selecting drivers above the statutory limit of 0.50g/kg.

Methadone concentrations in blood, plasma, and oral fluid determined by isotope-dilution gas chromatography-mass spectrometry.

Methadone (MTD) is widely used for detoxification of heroin addicts and also in pain management programs. Information about the distribution of methadone between blood, plasma, and alternative specimens, such as oral fluid (OF), is needed in clinical, forensic, and traffic medicine when analytical results are interpreted. We determined MTD and its metabolite 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine (EDDP) in blood, plasma, blood cells, and OF by gas chromatography-mass spectrometry (GC-MS) after adding deuterium-labeled internal standards. The analytical limits of quantitation for MTD and EDDP by this method were 20 and 3 ng/mL, respectively. The amounts of MTD and EDDP were higher in plasma (80.4 % and 76.5 %) compared with blood cells (19.6 % and 23.5 %) and we found that repeated washing of blood cells with phosphate-buffered saline increased the amounts in plasma (93.6 % and 88.6 %). Mean plasma/blood concentration ratios of MTD and EDDP in spiked samples (N = 5) were 1.27 and 1.21, respectively. In clinical samples from patients (N = 46), the concentrations of MTD in plasma and whole blood were highly correlated (r = 0.92, p < 0.001) and mean (median) plasma/blood distribution ratios were 1.43 (1.41). The correlations between MTD in OF and plasma (r = 0.46) and OF and blood (r = 0.52) were also statistically significant (p < 0.001) and the mean OF/plasma and OF/blood distribution ratios were 0.55 and 0.77, respectively. The MTD concentration in OF decreased as salivary pH increased (more basic). These results will prove useful in clinical and forensic medicine when MTD concentrations in alternative specimens are compared and contrasted.

Concentration ratios of free-morphine to free-codeine in femoral blood in heroin-related poisoning deaths.

The concentrations of free-morphine (Mo), free-codeine (Co) and 6-monoacetyl morphine (6-MAM) were determined in femoral blood in N=747 heroin-related deaths. The opiates were determined by isotope dilution gas chromatography-mass spectrometry after solid-phase extraction. The median blood concentrations of 6-MAM, free-morphine and free-codeine were 0.01 mg/L, 0.24 mg/L and 0.02 mg/L, respectively. The mean and median Mo/Co concentration ratios were 13.2 and 11.0, respectively with a range from 0.2 to 124. Despite the fact that all victims had taken heroin, there were eight cases (1.1%) with a Mo/Co ratio less than one and 18 cases (2.4%) with a ratio less than two. The free-morphine concentration in blood did not depend on the Mo/Co ratio; median 0.29 mg/L (Mo/Co<2.0) and median 0.25mg/L (Mo/Co ratio>2.0). By contrast, the concentration of free-codeine in blood was highly dependent on the Mo/Co ratio; median 0.75 mg/L (Mo/Co<1.0) and median 0.30 mg/L (Mo/Co ratio<2.0). A Mo/Co ratio in post-mortem (PM) femoral blood >1.0 is compelling evidence that the deceased had taken illicit heroin. However, finding a low Mo/Co ratio (<1.0 or <2.0) does not preclude use of heroin because such low ratios are possible if a person had co-ingested heroin along with use or abuse of codeine medication.

Driving under the influence of opiates: concentration relationships between morphine, codeine, 6-acetyl morphine, and ethyl morphine in blood.

Morphine and codeine are frequently identified in blood samples from impaired drivers. But whether these opiates reflect the use of prescription analgesics or abuse of the illicit drug heroin (diacetyl morphine) is not always obvious. Opiates, either alone or together with other drugs, were determined in 2,573 blood specimens from impaired drivers by sensitive and specific methods of analysis. The specific metabolite of heroin 6-acetyl morphine (6-AM) was quantifiable in only 52 cases (2%) at mean, median, and highest concentrations of 0.015, 0.010, and 0.10 mg/L, respectively. The mean, median, and highest concentrations of morphine were 0.046, 0.03, and 1.13 mg/L, respectively (N = 2,029). The corresponding concentrations of codeine (N = 1,391) were 0.047, 0.01, and 2.40 mg/L. Ethyl morphine was identified in 63 cases at a mean concentration of 0.055 mg/L (median 0.03 mg/L). When 6-AM was present in urine (N = 324), the mean morphine/codeine ratio in blood was 7.5 (median 6.7), and this important ratio was less than unity in only two cases. This study finds compelling evidence that approximately 90% of apprehended drivers in Sweden with morphine and codeine in their blood had used heroin.

High re-arrest rates among drug-impaired drivers despite zero-tolerance legislation.

BACKGROUND: A zero-tolerance law for driving under the influence of drugs (DUID) in Sweden led to a 10-fold increase in the number of cases submitted by the police for toxicological analysis. The statutory blood-alcohol concentration (BAC) limit for driving is 0.2 mg/g ( approximately 0.02 g%). METHODS: An in-house database (TOXBASE) was used to investigate re-arrests for impaired driving over 4 years (2001-2004), which comprised 36,799 cases. The age, gender, re-arrest rate of the offenders and the concentrations of ethanol and amphetamine in blood samples were evaluated. RESULTS: We found that 44% of individuals (N=16,277) re-offended 3.2 times on average (range 1-23 arrests). Between 85 and 89% of first-time offenders were men and there was also a male dominance among the recidivists (88-93%). The mean age of drunken drivers was approximately 40 years compared with approximately 35 years for driving under the influence of amphetamine, which was the drug identified in 50-60% of DUID cases, either alone or together with other licit or illicit drugs. The median BAC was 1.5mg/g ( approximately 0.15 g%), which suggests a dominance of heavy drinkers. The median BAC was even higher in recidivists (1.6-1.7 mg/g). The median concentration of amphetamine in blood was 1.0 mg/L in recidivists compared with 0.5mg/L in the first-time offenders. About 14% of drunken drivers re-offended 1-10 times compared with 68% of DUID suspects, who were re-arrested 1-23 times. People with only a scheduled prescription drug in blood were re-arrested much less frequently ( approximately 17%) compared with those taking illicit drugs (68%). CONCLUSIONS: The appreciable increase in number of arrests for DUID after a zero-tolerance law might reflect a heightened enthusiasm by the police authorities armed with knowledge that a prosecution is easier to obtain. Zero-tolerance laws do not deter people from impaired driving judging by the high re-arrest rates. During the sentencing of hardcore offenders, the courts should give more consideration to the underlying substance abuse problem.

Gamma-hydroxybutyrate concentrations in the blood of impaired drivers, users of illicit drugs, and medical examiner cases.

Gamma-hydroxybutyrate (GHB) was determined in blood samples from impaired drivers, people arrested for petty drug offenses (non-traffic cases), and GHB-related deaths. The method of analysis involved conversion of GHB into gamma-butyrolactone and determination of the latter by gas chromatography with a flame ionization detector, and with gamma-valerolactone as the internal standard. The mean and median concentrations of GHB in blood from impaired drivers (N=473) were 90 and 84 mg/L, respectively, and offenders were predominantly men (96%) with an average age of 26 year (range 15-50 year). In 185 cases, GHB was the only drug present in blood at mean and median concentrations of 92 and 86 mg/L, respectively. People arrested for petty drug offenses (N=1061) had slightly higher GHB concentrations in their blood: median 118 mg/L for men and 111 mg/L for women. In GHB-related deaths (N=33), the mean and median concentrations were considerably higher: 307 mg/L and 190 mg/L, respectively, and the highest was 2200 mg/L. The typical signs of drug influence noted by the arresting police officers included sedation, agitation, slurred speech, irrational behaviour, jerky movements, and spitting. The short elimination half-life of GHB means that the concentrations in blood decrease rapidly and are probably a lot lower than at the time of driving, which was 30-90 min earlier.

Predominance of illicit drugs and poly-drug use among drug-impaired drivers in Sweden.

OBJECTIVE: After Sweden's zero-tolerance law came into force (1 July 1999), the number of cases of driving under the influence of drugs (DUID) submitted by the police for toxicological analysis increased more than 10-fold. This prompted an in-depth investigation into the kinds of drugs used by DUID offenders, whether licit or illicit, and the frequency of their occurrence. METHODS: All blood samples from DUID suspects sent by the police for toxicological analysis over a 4-year period (2001-2004) were investigated (N = 22,777 cases). Specimens of blood or urine were subjected to a broad screening analysis by immunoassay methods aimed at detecting amphetamines, cannabis, opiates, cocaine metabolite, and the major benzodiazepines. All positive results from the screening stage were verified by use of more specific analytical methods (e.g., GC-MS, LC-MS, GC-FID, and GC-NPD). RESULTS: Between 80 and 85% of all the blood samples contained at least one banned substance and many contained two or more therapeutic and/or illicit drugs. About 15% of cases were negative for drugs, although these frequently (30-50%) contained ethanol above the legal limit for driving in Sweden, which is 0.20 mg/g (0.02 g%). Amphetamine was the most prominent illicit drug seen in 55-60% of cases either alone or together with other drugs of abuse. Stimulants like cocaine and/or its metabolite were infrequently encountered ( approximately 1.2% of cases). The next most prevalent illicit drug was cannabis, with positive results for tetrahydrocannabinol (THC) in blood either alone ( approximately 4%) or together with other psychoactive substances ( approximately 20%). Morphine, codeine, and/or 6-acetyl morphine were identified in approximately 2% of all DUID suspects, being indicative of heroin abuse. The major prescription drugs identified in blood were benzodiazepines (10%) as exemplified by diazepam, alprazolam, nitrazepam, and flunitrazepam. Drugs for treating insomnia, zolpidem and zopiclone, were also identified in blood samples from DUID suspects over the study period. Other therapeutic agents were encountered in only 1-2% of all cases. CONCLUSIONS: The dramatic increase in DUID after the zero-tolerance law came into force probably reflects enhanced police activity and more enthusiasm to apprehend and charge individuals for this offence. Illicit drugs, particularly amphetamine and cannabis, and poly-drug use were predominant compared with use of scheduled prescription drugs. The typical DUID offender in Sweden abuses central stimulants, particularly amphetamine, and has probably done so over many years. Options for treating offenders for their underlying substance abuse problem should be considered instead of the more conventional penalties for drug-impaired driving.

Are changes in blood-ethanol concentration during storage analytically significant? Importance of method imprecision.

BACKGROUND: Knowledge about the stability of drugs and metabolites in biological fluids is important information when the analytical results are evaluated and interpreted. This study examines changes in blood-ethanol concentration (BEC) during the storage of specimens for up to 12 months at 4 degrees C. METHODS: Venous blood samples were taken from drunk drivers in evacuated glass tubes containing sodium fluoride and potassium oxalate as chemical preservatives. The concentrations of ethanol in blood were determined in duplicate by headspace gas chromatography on arrival at the laboratory and again after storage in a refrigerator at 4 degrees C for up to 12 months. RESULTS: The relationship between the standard deviation (SD) of analysis of ethanol at concentration intervals of 0.2 mg/g (BEC) was defined by the linear regression equation SD=0.00243+0.0104 BEC (r=0.99). At a mean BEC of 1.64 mg/g, the SD was 0.019 mg/g which corresponds to a coefficient of variation of 1.1%. The mean decrease in BEC (+/-SD) between first and second analysis was 0.105+/- 0.0686 mg/g (t=19.3, d.f.=158, p<0.001) and the loss of alcohol was positively correlated with the duration (days) of storage (r=0.44, p<0.001), although with large inter-tube variations. A correlation also existed (r=0.23, p<0.01) between the loss of ethanol and the starting BEC. When blood samples (n=49) were opened 17 times to remove aliquots for analysis over 6.5 months, the BEC decreased by 0.217+/-0.054 mg/g compared to a fall of 0.101+/-0.076 mg/g in tubes kept unopened. None of the blood samples showed a significant increase in BEC after storage. CONCLUSIONS: To be considered analytically significant, the BEC had to decrease by 0.013 (2.6%), 0.028 (1.9%) and 0.045 mg/g (1.8%), respectively at starting concentrations of 0.5, 1.5 and 2.5 mg/g.

Does consumption of ethanol distort measurements of exhaled nitric oxide?

BACKGROUND: Measuring FE(NO) is a novel and non-invasive way to monitor airway inflammation (e.g. asthma). This clinical study was designed to investigate whether drinking ethanol might distort FE(NO) measurements. METHODS: Twenty healthy subjects drank 0.40 g ethanol/kg body weight in 15 min. Measurement of FE(NO) started approximately 30 min before drinking and at various times afterwards for 4 h post-dosing. Ethanol concentrations were determined in venous blood by gas chromatography and in end-exhaled breath by infra-red spectrometry. RESULTS: The within subject standard deviation for determination of FE(NO) was 1.3 ppb, corresponding to a CV of 7.7%. The mean change in FE(NO) from pre-drinking levels during the 4h testing was statistically significant (P<0.001) according to repeated measures ANOVA. In absolute units the mean change was small, -2.01 and -1.94 ppb at 3 and 4h post-dosing, respectively (P<0.013, P<0.005). CONCLUSIONS: FE(NO) measurements were reproducible even in subjects with moderate concentrations of ethanol in blood and breath. The small decrease in FE(NO) observed at 3 and 4 h post-drinking was less than the intra-subject variations in FE(NO) measurements. The breath-alcohol concentrations in this study exceed all other endogenous volatiles, thus making it unlikely that other substances in human breath will bias the FE(NO) measurements.

Role of variability in explaining ethanol pharmacokinetics: research and forensic applications.

Variability in the rate and extent of absorption, distribution and elimination of ethanol has important ramifications in clinical and legal medicine. The speed of absorption of ethanol from the gut depends on time of day, drinking pattern, dosage form, concentration of ethanol in the beverage, and particularly the fed or fasting state of the individual. During the absorption phase, a concentration gradient exists between the stomach, portal vein and the peripheral venous circulation. First-pass metabolism and bioavailability are difficult to assess because of dose-, time- and flow-dependent kinetics. Ethanol is transported by the bloodstream to all parts of the body. The rate of equilibration is governed by the ratio of blood flow to tissue mass. Arterial and venous concentrations differ as a function of time after drinking. Ethanol has low solubility in lipids and does not bind to plasma proteins, so volume of distribution is closely related to the amount of water in the body, contributing to sex- and age-related differences in disposition. The bulk of ethanol ingested (95-98%) is metabolised and the remainder is excreted in breath, urine and sweat. The rate-limiting step in oxidation is conversion of ethanol into acetaldehyde by cytosolic alcohol dehydrogenase (ADH), which has a low Michaelis-Menten constant (Km) of 0.05-0.1 g/L. Moreover, this enzyme displays polymorphism, which accounts for racial and ethnic variations in pharmacokinetics. When a moderate dose is ingested, zero-order elimination operates for a large part of the blood-concentration time course, since ADH quickly becomes saturated. Another ethanol-metabolising enzyme, cytochrome P450 2E1, has a higher Km (0.5-0.8 g/L) and is also inducible, so that the clearance of ethanol is increased in heavy drinkers. Study design influences variability in blood ethanol pharmacokinetics. Oral or intravenous administration, or fed or fasted state, might require different pharmacokinetic models. Recent work supports the need for multicompartment models to describe the disposition of ethanol instead of the traditional one-compartment model with zero-order elimination. Moreover, appropriate statistical analysis is needed to isolate between- and within-subject components of variation. Samples at low blood ethanol concentrations improve the estimation of parameters and reduce variability. Variability in ethanol pharmacokinetics stems from a combination of both genetic and environmental factors, and also from the nonlinear nature of ethanol disposition, experimental design, subject selection strategy and dose dependency. More work is needed to document variability in ethanol pharmacokinetics in real-world situations.

[5-HTOL--a new biochemical alcohol marker with forensic applications]. / 5-HTOL--ny biokemisk alkoholmarkör med rättsmedicinska tillämpningar.

The concentration of ethanol in blood and urine provides important evidence in criminal and civil litigation when alcohol-related crimes are investigated (e.g., drunk driving). The determination of ethanol in body fluids is a routine procedure at forensic chemistry and toxicology laboratories and when gas chromatographic methods are used accurate and precise results are obtained. However, the risk for artifactual formation of ethanol, especially in postmortem specimens, always needs to be considered. The ratio of 5-HTOL/5-HIAA in urine provides a useful way to distinguish between ethanol produced after death, or generated in vitro after sampling, from the ethanol consumed. This article describes the application of the 5-HTOL/5-HIAA ratio as a biochemical marker for acute alcohol intake in various forensic situations. Examples include suspected drunk drivers, rape victims, and medico-legal autopsies where forensic ethanol analysis is requested.

Pharmacokinetics of Ethanol in Arterial and Venous Blood and in End-Expired Breath during Vasoconstriction and Vasodilation.

We studied the influence of vasoconstriction and vasodilation on the concentrations and the pharmacokinetics of ethanol in arterial blood (a), venous blood (v), and end-expired breath (b). Ethanol 0.4 g kg(minus sign1) was given by intravenous infusion over 30 min to 12 healthy male volunteers, once in the morning and again in the afternoon the same day. During one infusion, the hand used to obtain venous blood was either cooled in water to 13--15 degreeC (N = 6 subjects) or warmed in a heating box at 60 degreeC (N = 6 subjects). Our results show that a--v differences and the pharmacokinetics of ethanol are sensitive to the constriction or dilation of blood vessels caused by local cooling or heating. Cooling of the hand doubled the a--v and b--v differences during infusion of ethanol, whereas warming reduced these differences by 10--80%. The a--b difference was positive during infusion but always became negative within 5 min after the infusion ended. However, cooling maintained the increased a--v difference for another 45 min after the infusion. Fitting of the data into a pharmacokinetic model consisting of a first-order distribution function and a zero-order (saturated Michaelis--Menten) elimination function showed that cooling altered the pharmacokinetic parameters describing the elimination of ethanol, whereas warming altered the parameters describing the distribution phase.

Rate of Distribution of Eethanol into the Total Body Water.

Nonequilibrium distribution of ethanol in the total body water (TBW) has implications for understanding gross intoxication seen after rapid consumption of alcohol and for certain new clinical monitoring methods where ethanol is used as a tracer. We studied the rate of distribution of ethanol into the TBW from the concentration--time profiles in whole blood after 0.4 g kg(minus sign1) of ethanol was given by intravenous over 15, 30, 45, and 60 min to six female volunteers. We also gave these females 0.6 g kg(minus sign1) over 30 min, and five young males 0.4 g kg(minus sign1) over 30 min. The results suggest that the blood ethanol concentration after rapid infusion can be described by a two-compartment model with first-order distribution kinetics and zero-order (saturated Michaelis--Menten) elimination. Distribution of ethanol occurred with a half-time of 6.6 plus minus 2.6 min (mean plus minus SD). Alcohol intoxication was more pronounced when ethanol was given rapidly. We conclude that predictable differences in the concentration of ethanol between the blood and the peripheral tissues during rapid supplementation of ethanol causes higher concentrations in blood and a more pronounced intoxication.