The prevalence of drugs and alcohol found in road traffic fatalities: A comparative study of victims

Researchers have studied the involvement of drugs and alcohol in fatal road traffic incidents, but with particular emphasis on the possible impairment of the driver. This paper describes a comparative study of drug and alcohol findings in various victim groups (drivers of cars, vans or lorries, car passengers, motorcyclists, motorcycle passengers, cyclists and pedestrians) between 2000 and 2006. Post-mortem blood and urine specimens submitted were analysed by immunoassay, GC–NPD, GC–FID, GC–MS and HPLC–DAD. The results of 1047 cases indicated 54% of all victims were positive for drugs and/or alcohol, with the highest percentage of positive findings occurring in pedestrians (63%). Males between the ages of 17–24 were most likely to be involved in a road traffic accident, whether being in control of a vehicle (driver) or involved indirectly (car passenger, pedestrian, motorcycle passenger). A wide range of drugs were detected (e.g. drugs of abuse, anti-convulsants, anti-histamines, anti-inflammatories, anti-psychotics, cardiac drugs and over-the-counter products), but alcohol and cannabinoids were the most frequent substances across the victim groups. When detected, alcohol was commonly above the legal driving limit in blood and urine (> 63% in those in control and > 60% not in control). Overall, the presence of drugs and/or alcohol was of similar frequency in those victims in control (55% of driver, 48% of motorcyclists, 33% of cyclists) and not in control of a vehicle (52% of car passengers, 63% of pedestrians). This degree of frequency strongly implicates the involvement of drugs and alcohol in road traffic incidents and infers an effect on driving ability and individual impairment.     

Ethanol distribution ratios between urine and capillary blood in controlled experiments and in apprehended drinking drivers.

Healthy men drank 0.51, 0.68, and 0.85 g of ethanol per kilogram of body weight as neat whisky in the morning after an overnight fast. During 6 to 8 h after the whisky was consumed, nearly simultaneous specimens of fingertip blood and pooled bladder urine were obtained for analysis of ethanol using an enzymatic method. The mean ratios of ethanol concentration [urine alcohol concentration (UAC)/blood alcohol concentration (BAC)] were mostly less than unity during the absorption phase. The UAC exceeded the BAC in the postpeak phase. The mean UAC/BAC ratios varied between 1.4 and 1.7 when the BAC exceeded 0.50 mg/mL. When the BAC decreased below 0.40 mg/mL, the UAC/BAC ratios increased appreciably. The mean UAC/BAC ratios of ethanol were not dependent on the person's age between the ages of 20 and 60 years old, but there were large variations within the age groups. In apprehended drinking drivers (N = 654) with a mean BAC of 1.55 mg/mL, the UAC/BAC ratio of ethanol varied widely, with a mean value of 1.49. In 12 subjects (3.2%), the ratio was less than or equal to unity. In a second specimen of urine obtained approximately 60 min after an initial void (N = 135), the mean UAC/BAC ratio was 1.35 (standard deviation = 0.17). The magnitude of the UAC/BAC ratio of ethanol can help to establish whether the BAC curve was rising or falling at or near the time of voiding. The status of alcohol absorption needs to be documented if drinking drivers claim ingestion of alcohol after the offence or when back-estimation of the BAC from the time of sampling to the time of driving is required by statute.     

Fatal accidents and blood ethanol levels in adolescents and adults. The Wayne County experience, 1978-1988

The files of 874 fatal traumatic accident victims, aged 12-25 years, examined at the Wayne County Medical Examiner's Office during the period 1978-1988 were reviewed. Postmortem blood alcohol results of individuals who died after less than 15 min of hospitalization were utilized to approximate alcohol levels at the time of the fatal injury. Relationships between types of accidents, sex, age, race, and time of accident were examined. White victims were far more likely to have been drinking than blacks, and the data indicated that underaged drinkers were involved in fatal accidents at lower levels of blood alcohol than their counterparts of legal drinking age. Consistent racial differences in average alcohol levels were not observed, however. Unlike female and black victims, who much less frequently tested positive for alcohol when underage, white male victims 16-21 years of age were just as likely to have been drinking as those aged 21-25. The results of the study show that postmortem blood alcohol level can be used to identify differences in alcohol consumption among groups of accident victims in a major metropolitan area.     

Excretion of alcohol in urine and diuresis in healthy men in relation to their age, the dose administered and the time after drinking

Healthy male volunteers drank neat whisky in amounts corresponding to 0.51, 0.68, or 0.85 g ethanol/kg body weight in 15-25 min after an overnight (10 h) fast. Urine was collected immediately before drinking and then at 60 min intervals for 7-8 h after intake. The volumes of urine voided were measured and the concentrations of alcohol (UAC) were determined by an enzymatic method. Ethanol-induced diuresis showed large inter-subject variations. The flow of urine was maximum between 60 and 120 min post-drinking when the median rates of production were 117 ml/h (range 55-335), 113 ml/h (range 41-453) and 373 ml/h (range 215-485) for 0.51, 0.68, and 0.85 g ethanol/kg respectively. The output of urine returned to normal (30-60 ml/h) after the peak UAC had passed despite an elevated blood alcohol concentration (BAC). The average amount of alcohol excreted in urine was 0.29 g (S.D. 0.119), 0.44 g (S.D. 0.246), and 1.00 g (S.D. 0.427) after the consumption of 0.51, 0.68 and 0.85 g ethanol/kg respectively. Neither peak diuresis nor the amount of alcohol excreted depended on a subject's age between 20 and 60 years. This work shows that after drinking a moderate dose of alcohol, only 0.7-1.5% of the amount consumed is excreted unchanged in urine. Ethanol-induced diuresis is most pronounced for the first 1-2 h after drinking (rising BAC). The production of urine returns to normal during the post-absorptive state.     

Acute lethal alcohol intoxication (author's transl)]

In 14,744 autopsy cases from an 18-year period 92 cases (of which 7 were ruled out because of decomposition were observed in which death was supposed to be due to direct acute alcoholic intoxication. In the police reports 81 persons were designated as chronic alcoholics or abusers of spirits. The blood alcohol level ranged between 2.04 and 4.92 o/oo. The cases studied were divided into two groups, one with low and the other with high lethal alcohol level. Fatty liver and cirrhosis were found with identical frequency in the two groups, whereas cardiac hypertrophy of obscure origin occurred markedly more often in the group with low lethal blood alcohol level. On the basis the possible mechanism of death in the cases with cardiac hypertrophy is discussed. Finally, the relation between the blood and urine alcohol concentrations observed in 72 cases is discussed. On the assumption that the water phase of the blood was 75 per cent of the total blood, death occurred in the persons without cardiac hypertrophy with fairly identical frequency either in the phase of absorption or the phase of elimination, whereas in the persons with cardiac hypertrophy death most often occurred in the phase of absorption. These statements should, however, be taken with some reservation, partly because the water phase of the blood may vary considerably post mortem (60-90 per cent) and partly because the urine alcohol concentration depends on serval variable factors.     

Relationship between blood and urine alcohol concentrations in apprehended drivers who claimed consumption of alcohol after driving with and without supporting evidence

For various reasons, many people suspected of driving under the influence of alcohol (DUIA) are not apprehended sitting behind the wheel, but some time after the driving. This gives them the opportunity to claim they drank alcohol after the time of driving or after they were involved in a road-traffic crash. Alleged post-offence drinking is not easy for the prosecution to disprove, which often means that the DUIA charge is dropped or the person is acquitted if the case goes to trial. The routine practice of sampling and measuring the concentration of alcohol in blood (BAC) and urine (UAC) and calculating urine/blood ratios (UAC/BAC) and the changes in UAC between two successive voids furnishes useful information to support or challenge alleged drinking after driving. We present here a retrospective case series of DUIA offenders (N = 40) in half of which there was supporting evidence of an after-drink (eye witness or police reports) and in the other half no such evidence existed apart from the suspect's admission. When there was supporting evidence of an after-drink, the UAC/BAC ratio for the first void was close to or less than unity (mean 1.04, median 1.08, range 0.54–1.21) and the UAC increased by 0.21 g/L (range 0.02–0.57) between the two voids. Without any supporting evidence of post-offence drinking the mean UAC/BAC ratio was 1.46 (range 1.35–1.93) for the first void, verifying that absorption and distribution of alcohol in all body fluids and tissues was complete. In these cases, the UAC between successive voids decreased by 0.25 g/L on average (range 0.10–0.49), indicating the post-absorptive phase of the BAC curve. Long experience from investigating claims of post-offence drinking leads us to conclude that in the vast majority of cases this lacks any substance and is simply a last resort by DUIA offenders to evade justice. Unless supporting evidence exists (eye witness, police reports, etc.) of post-offence drinking the courts are encouraged to ignore this defence argument.     

Drug and alcohol involvement in railroad accidents

Postaccident testing of railroad employees for drugs and alcohol was performed in 175 qualifying accidents or incidents (events) from April 1987 through March 1988. Initial tests for drugs were performed on urine, and for alcohol on blood. Presumptive positives were confirmed and quantitated using both blood and urine when available. In 42 of these events (24%), at least 1 employee tested positive (6.7% of 736 employees) for drugs or alcohol. A higher proportion of drug or alcohol-positive events, or both, 40 versus 21%, was found when a fatality was involved. In 11 of the 32 fully investigated drug or alcohol-positive events (involving 14 employees), the investigating agencies determined that substance use was determined to be a probable cause of, or a factor relating to, the accident. Cannabinoids, ethanol, cocaine, or multiple-drug use were found in 5, 3, 3, and 3 of those employees, respectively. Detectable drug and alcohol use occurs among railroad employees; occasionally it has resulted in accidents.     

Breath alcohol concentration determined with a new analyzer using free exhalation predicts almost precisely the arterial blood alcohol concentration

A new breath alcohol (ethanol) analyzer has been developed, which allows free exhalation, standardizes measured exhaled alcohol concentration to fully saturated water vapor at a body temperature of 37 degrees C (43.95 mg/L) and includes a built-in self-calibration system. We evaluated the performance of this instrument by comparing standardized alcohol concentration in freely expired breath (BrAC) with arterial (ABAC) and venous (VBAC) blood alcohol concentrations in fifteen healthy volunteers who drank 0.6 g of alcohol per kg body weight. The precision (coefficient of variation, CV) of the analyzer based on in vivo duplicate measurements in all phases of the alcohol metabolism was 1.7%. The ABAC/BrAC ratio was 2251+/-46 (mean+/-S.D.) in the post-absorptive phase and the mean bias between ABAC and BrAC x 2251 was 0.0035 g/L with 95% limits of agreement of 0.033 and -0.026. The ABAC and BrAC x 2251 were highly correlated (r=0.998, p<0.001) and the regression relationship was ABAC = 0.00045 + 1.0069 x (BrAC x 2251) indicating excellent agreement and no fixed or proportional bias. In the absorption phase, ABAC exceeded BrAC x 2251 by at most 0.04+/-0.03 g/L when tests were made at 10 min post-dosing (p<0.05). The VBAC/BrAC ratio never stabilized and varied continuously between 1834 and 3259. There was a proportional bias between VBAC and BrAC x 2251 (ABAC) in the post-absorptive phase (p<0.001). The pharmacokinetic analysis of the elimination rates of alcohol and times to zero BAC confirmed that BrAC x 2251 and ABAC agreed very well with each other, but not with VBAC (p<0.001). We conclude that this new breath analyzer using free exhalation has a high precision for in vivo testing. The BrAC reflects very accurately ABAC in the post-absorption phase and substantially well in the absorption phase and thereby reflects the concentration of alcohol reaching the brain. Our findings highlight the magnitude of arterio-venous differences in alcohol concentration and support the use of breath alcohol analyzers as a stand-alone test for medical and legal purposes.     

An epidemiological study on alcohol/drugs related fatal traffic crash cases of deceased drivers in Hong Kong between 1996 and 2000

This study is designed to evaluate the correlation between fatal vehicle crashes (FVC) and consumption of alcohol and/or drugs among drivers. Between 1996 and 2000 in Hong Kong, a total of 197 FVC cases of deceased drivers were investigated. The blood and/or urine samples of the victims were examined for the presence of alcohol and drugs. The 197 cases were then classified into two groups: single-vehicle crashes (SVC) and multiple-vehicle crashes (MVC). Out of the 106 cases for the latter group, alcohol and/or drugs were detected in 22 cases (21%) while the remaining 84 cases (79%) were regarded as no significant finding. As for the 91 cases in SVC group, 51 cases (56%) were positive for alcohol and/or drugs. The findings indicate that a driver consuming alcohol and/or drugs has a higher risk of being involved in a FVC. The most frequently detected drugs for SVC group (11 cases) were: 46% central nervous system (CNS) stimulants (including designer drugs like MDMA); 36% cannabis; 18% benzodiazepines and 9% ketamine. The detected drug for the only case in the MVC group was a CNS stimulant. The number of cases with ketamine, methamphetamine and MDMA detected has increased in recent years as these party drugs have gained popularity in Hong Kong.     

Physiological variations in blood ethanol measurements during the post-absorptive state

Specimens of arterial plasma and venous whole blood were obtained at 3-10 min intervals during the post-peak phase of ethanol metabolism in healthy volunteers. The concentrations of ethanol in blood and plasma were determined by headspace gas chromatography. This method had a standard deviation of 0.28 mg/dl for whole blood and 0.26 mg/dl for plasma and the coefficients of variation were 0.43% and 0.79% respectively. The physiological variation from time-to-time, expressed as the residual standard deviation after fitting the ethanol concentration-time regression relationships, ranged from 0.43-3.7 mg/dl (0.65-16%). The time-to-time variations in concentrations of ethanol were maximum when there were problems in getting an unimpeded flow of blood through the indwelling catheters. The results do not support the existence of sporadic fluctuations or spiking in the blood alcohol concentration-time profile during the post-absorptive state. Instead, this study underscores the need to control carefully the method of sampling blood and in this way keep pre-analytical sources of variation to a minimum.     

Role of drugs in traffic accidents. A pilot study of traffic accident offenders in Switzerland (Bern region)

Toxicological analyses of blood and/or urine specimens collected between 1980 and 1981 revealed that 34.7% of all traffic accident victims (n = 144) had measurable concentrations of drugs. Analyses of blood samples taken from traffic offenders (n = 250) in 1979, on the other hand, showed 22.4% to have consumed drugs with or without alcohol. This percentage is comparable with values reported in other studies. Our results indicate that the widespread use of drugs represents a hazard for traffic safety in Switzerland. Road safety is additionally jeopardized by the often concomitant consumption of alcohol.     

Traumatic rupture of the basilar artery: report of two cases and review of the literature

Two cases of traumatic rupture of the basilar artery are reported. In the first case, severe basal subarachnoid hemorrhage (SAH) due to a complete transverse tear of the basilar artery was observed in a 53-year-old restrained male driver who was involved in a head-on collision while intoxicated and drowsy. He lost consciousness shortly after the accident and was admitted to hospital in cardiopulmonary arrest. Intensive resuscitative therapies produced cardiac response, but he died 50 minutes after the accident. The ethanol concentration in his blood and urine was 0.35 and 0.55 mg/ml, respectively. In the second case, SAH due to a similar tear of the basilar artery was observed in a 47-year-old man who received several fist blows to the face while intoxicated. He suddenly lost consciousness after the final blow and was admitted to hospital in cardiopulmonary arrest. Intensive resuscitative therapies produced cardiac response, but he died 6 hours after the event. In these cases, the mechanism of the traumatic rupture of the basilar artery is thought to be overstretching due to hyperextension of the head, and intoxication, drowsiness, or both may have interfered with the decedents' ability to protect themselves; thus, the hyperextension of the head may have been rather forceful.     

Driving under the influence of alcohol and/or drugs in the Netherlands 1995-1998 in view of the German and Belgian legislation

This study presents the test results of blood and urine samples of impaired drivers in the Netherlands between January 1995 and December 1998. In this period, the blood alcohol concentrations of 11,458 samples have been determined and 1665 blood or urine samples have been analysed for drugs. The median alcohol concentration was between 1.7 and 1.8 mg/ml blood. In 80% of the 1665 analysed samples drugs were detected. At least 42% (702/1665) of the impaired drivers were poly-drug users, with cocaine present in the most frequent combinations. In the Netherlands, the procedure to prove driving under the influence is complex. This procedure can be made more efficient and more effective by embedding the analytical test results, needed to prosecute an impaired driver, in the law. In Belgium and Germany, such laws already are in force. If we would apply the qualifications of the new Belgian law on our analytical data, 67% of the impaired drivers included in this comparison could have been prosecuted without discussion in court.     

Driving under the influence of alcohol and/or drugs in the Netherlands 1995–1998 in view of the German and Belgian legislation

This study presents the test results of blood and urine samples of impaired drivers in the Netherlands between January 1995 and December 1998. In this period, the blood alcohol concentrations of 11,458 samples have been determined and 1665 blood or urine samples have been analysed for drugs. The median alcohol concentration was between 1.7 and 1.8 mg/ml blood. In 80% of the 1665 analysed samples drugs were detected. At least 42% (702/1665) of the impaired drivers were poly-drug users, with cocaine present in the most frequent combinations. In the Netherlands, the procedure to prove driving under the influence is complex. This procedure can be made more efficient and more effective by embedding the analytical test results, needed to prosecute an impaired driver, in the law. In Belgium and Germany, such laws already are in force. If we would apply the qualifications of the new Belgian law on our analytical data, 67% of the impaired drivers included in this comparison could have been prosecuted without discussion in court.     

Alcohol metabolism of local Chinese in Hong Kong: a statistical determination on the effects of various physiological factors

A study was designed to examine the elimination rate of alcohol from the body of the local Chinese after consumption of different types of alcoholic drinks. The breath alcohol of 184 healthy volunteers was determined and converted into blood alcohol levels after they finished drinking. Information on the type and volume of alcoholic drinks consumed, age group, sex, drinking habit, and drinking on empty stomach or with/after meal was recorded for each participant. The results show that the elimination rate of an individual can be explained in terms of physiological variables including sex and drinking habit. The determined elimination rates allow forensic toxicologists to back calculate the blood alcohol concentration (BAC) of the drivers at the time of accident in drunk driving cases. The elimination rates of blood alcohol at 95% prediction intervals for male and female are in the range of 9.5-23.8 mg/100 ml/h and 11.1-37.1 mg/100 ml/h, respectively.     

两轮摩托车道路交通事故驾驶员损伤特征分析

目的找出两轮摩托车交通事故中多发于驾驶员而乘员较少发生的损伤特征,为查明案件提供线索。方法统计分析了有驾乘人员死亡的136例及有驾乘人员受伤的32例,以体表擦挫伤、挫裂伤或骨折作为统计对象,分别统计驾乘人员各部位发生损伤数并计算其出现的比例。结果驾驶员出现膝部损伤的比例（34．9％）高于乘员比例（i0．3％）,而驾驶员膝部损伤大多数发生在膝部前侧。结论膝部前侧损伤的当事人应高度怀疑其为真实驾驶员。     

Causes and circumstances of fatal falls downstairs

Reports of 9156 autopsies performed at the Centre of Legal Medicine of the J.W. Goethe-University Frankfurt over a period of 10 years were reviewed for fatal accidents of falls downstairs, age, gender, drinking behaviour and alcohol influence, the locality and the time of the accident. Among 43 cases (0.47% of all autopsies) were 31 males (72.1%, average age 63.9 years) and 12 women (27.9%, average age 65.8 years). Twenty-nine accidents (67.4%) occurred at home, in six cases (14.0%) in a public building or area. Twenty-three victims (53.5%) were under the influence of alcohol (average blood alcohol concentrations (BAC): 2.56 per thousand), in 19 persons autopsy revealed severe internal disease which may explain the cause of the fall (severe coronary artery disease, myocardial hypertrophy, myocardial infarction, apoplexy, brain tumour). This study indicates that a fatal fall downstairs without an underlying severe disease or alcohol influence is a rare phenomenon.     

Detection of drugs of abuse in simultaneously collected oral fluid, urine and blood from Norwegian drug drivers

Blood and urine samples are collected when the Norwegian police apprehend a person suspected of driving under the influence of drugs other than alcohol. Impairment is judged from the findings in blood. In our routine samples, urine is analysed if morphine is detected in blood to differentiate between ingestion of heroin, morphine or codeine and also in cases where the amount of blood is too low to perform both screening and quantification analysis. In several cases, the collection of urine might be time consuming and challenging. The aim of this study was to investigate if drugs detected in blood were found in oral fluid and if interpretation of opiate findings in oral fluid is as conclusive as in urine. Blood, urine and oral fluid samples were collected from 100 drivers suspected of drugged driving. Oral fluid and blood were screened using LC-MS/MS methods and urine by immunological methods. Positive findings in blood and urine were confirmed with chromatographic methods. The analytical method for oral fluid included 25 of the most commonly abused drugs in Norway and some metabolites. The analysis showed a good correlation between the findings in urine and oral fluid for amphetamines, cocaine/benzoylecgonine, methadone, opiates, zopiclone and benzodiazepines including the 7-amino-benzodiazepines. Cocaine and the heroin marker 6-monoacetylmorphine (6-MAM) were more frequently detected in oral fluid than in urine. Drug concentrations above the cut-off values were found in both samples of oral fluid and urine in 15 of 22 cases positive for morphine, in 18 of 20 cases positive for codeine and in 19 of 26 cases positive for 6-MAM. The use of cannabis was confirmed by detecting THC in oral fluid and THC-COOH in urine. In 34 of 46 cases the use of cannabis was confirmed both in oral fluid and urine. The use of cannabis was confirmed by a positive finding in only urine in 11 cases and in only oral fluid in one case. All the drug groups detected in blood were also found in oral fluid. Since all relevant drugs detected in blood were possible to find in oral fluid and the interpretation of the opiate findings in oral fluid was more conclusive than in urine, oral fluid might replace urine in driving under the influence cases. The fast and easy sampling is time saving and less intrusive for the drivers.