Fatal traffic accidents in which no alcohol is detected: Are drugs related?

Transcription

1 T2007 Seattle, Washington Fatal traffic accidents in which no alcohol is detected: Are drugs related? Rosario García-Repetto *, Mª Luisa Soria, Mª Paz Giménez and Carmen Jurado. National Institute of Toxicology and Forensic Sciences, Department of Seville Avda. Dr. Fedriani s/n Seville, Spain Key Words: ethanol non detected, presence of drugs, road accidents ABSTRACT Driving performance is easily impaired as consequence of the use of alcohol and or illicit and medicinal drugs. However, the role of drugs other than alcohol in motor vehicle accidents has not been well established. The aim of this study was to assess the presence of psychoactive substances other than alcohol among drivers killed in road accidents in Southern Spain from During this period, the Department of Seville of the Spanish National Institute of Toxicology received a total of 952 blood samples from drivers dead in road accidents; in 491 of them no alcohol was detected. These cases are the aim of the present study. INTRODUCTION One of the issues that arises higher distress in our society is death due to road accidents, because of to its high incidence in Spain. Driving under the influence of drugs of that affect the central nervous system is one issues of growing concern in road safety. For many years, attention has primarily focused on alcohol and legal limits for blood alcohol concentration during driving have been established. However, during the last years drugs other than alcohol have attracted increasing attention, due to a dramatic increase of use and also due to the zero-tolerance laws that exists in Spain. The relationship between alcohol consumption and the increased the risk of having a traffic accident due to the impairment of driving skills, has been extensively studied. The risk of suffering a road accident increases with blood ethanol concentration. Driving under the influence of drugs other than alcohol is considered to be an increasing cause of traffic accidents worldwide (1). There are several studies that have also shown that illicit drugs and certain prescription drugs, such as amphetamines, antihistaminics, cannabis, hypnotics, tranquilizers and tricyclic antidepressant (2, 3) also impair driving skills and can increase crash risk. However, for most of these substances no clear concentration-effect relationship has been established. Current legislation in Spain states that one may not drive under the influence of psychoactive substances that may alter the physical or mental state in which one is fit to drive without danger. Whereas drivers are allowed to drive if blood concentration is below 0.5 g/l (or 0.25 mg/l in exhaled air), no limit has been established for psychoactive drugs concentrations in driver s blood. (R.D. 13/1992)

2 The objective of this study was to get an insight into the prevalence of medicinal and illegal drugs among car drivers, in which alcohol was not detected, killed in road accidents in Southern Spain over a 2-year period ( ). During this period, the Department of Seville of the Spanish National Institute of Toxicology received a total of 952 blood samples from drivers dead in road accidents; in 491 of them no alcohol was detected. These cases are the aim of the present study. MATERIAL AND METHODS Blood specimens were collected by the coroner and kept in tubes with natrium fluoride as a preservative and calcium oxalate as antioxidative. On their arrival to the laboratory, all specimens were stored at 4 C until their extraction. Toxicological analyses were performed in all samples received following our laboratory normal procedures. Ethanol was analysed by means of headspace GC-FID (4). Screening of drugs of abuse was performed by means of homogeneous enzyme immunoassay CEDIA (5). Blood samples were extracted by SPE (Bond-Elut certified columns), following the normal procedure in our laboratory (6), which involves the employment of nalorphine as internal standard for opiates, cocaine and methadone and prazepam as internal standard for benzodiazepines. Blood samples were sonicated prior to extraction for 10 minutes and ph was adjusted to 9 with KOH 1N. Sample was then centrifuged 10 minutes at 2500 r.p.m. Supernatant was extracted by means of SPE. The presence of opiates, cocaine and its metabolites and methadone in specimens were confirmed and quantitated by GC-MS. Dry residues were heated 20 minutes at 70 C with 50μL of the derivatization reagent, BSTFA (bis(trimethylsilyl) trifluoro acetamide)). Cannabis derivatives were confirmed by means of GC-MS in SIM mode after derivatization with heptafluorobutyric anhydride and 1,1,1,-2,2,2-hexafluoro-isopropanol The presence of benzodiazepines were confirmed and quantitated by means of HPLC with DAD detector working at 230 nm. RESULTS Blood samples from 952 people killed in road accidents were received; in 491 of these samples no ethanol was detected. An 84.52% of the samples were from men and only a 15.47% from women. Age distribution of studied cases was as follows: 8.96% under 20 years old, a 24.85% between years, a 22.40% between years, a 14 46% between years; an 8.55% between years and a 16.29% were above 60 years old.

3 371 cases (76.66%) tested also negative for the presence of drugs and 120 (24.44%) cases yielded positive results for illegal drugs and medicinal substances. The illegal drugs most frequently found were cannabis (THC) (n = 21), cocaine and its metabolites (n = 20). Among psychoactive drugs, benzodiazepines were the most common (n=53). Other psychoactive drugs found were citalopram, venlafaxine, mirtazapine and zolpidem. DISCUSSION This study shows that the majority of drivers killed were men between 21 and 40 years old. Although the majority of the cases yielded negatives results also for psychoactive drugs, there is a remarkable presence of them (24.44%) in drivers killed in road accidents in southern Spain, which cannot be underestimated. The presence of illicit drugs (10.79%) and medicinal drugs (13.64%) are similar to those reported by Del Río et al.(7) for Spanish drivers killed in road accidents. Benzodiazepines were the most commonly detected medicinal drugs (10.79%), according to the fact that the use of benzodiazepines is particularly common in our country in relation to other industrialised countries (8). These results agree with previous reports. It is interesting to point out that midazolam (n=29) represented approximately one half of the cases positives for benzodiazepines. This is probably due to intensive care treatment administered to injured drivers. We find a similar proportion of cases in with cannabis (4.27%) and cocaine (4.07%) positives results. These results are different to those reported previously by Del Río et al. (7, 9). They found a major proportion of cocaine positives cases than cannabis ones for drivers killed in road accidents in Spain. However, our results are in good accordance with others reports and also agree with the fact that cannabis is the illegal drug most frequently consumed in Spain, as well as in other European countries. Our results also reflect the prevalence of cocaine use in Spanish society, being the second most frequent consumed drug (10). The median Δ 9 -THC concentration was ng/ml ( ng/ml), and 86.96% of the cases had Δ 9 -THC. Δ 9 -THC concentrations 5 ng/ml, which is the level, associated by others authors with a significant decrement in driving performance (11). Cocaine was detected only in 8 cases while its metabolite benzoylecgonine was detected in 20.The median benzoylecgonine concentration was 1.47 mg/l ( mg/l), which are similar to those reported previously by Mura et al. (12). It is also remarkable the fact that no amphetamine derivative was detected in any of the samples analysed. This situation is completely different to what have been reported previously (7, 9, 12). CONCLUSIONS

4 The present study shows that a significant proportion of drivers dead in road accidents were under the influence of psychoactive drugs while they have not drunk alcohol. Therefore, its confirms the need of establishing the presence or not of psychoactive drugs in all specimens received from fatal traffic accidents in order to explain, if possible, their influence on the accident s causes. REFERENCES 1. Morland J. (2000) Driving under the influence of non-alcohol drugs. Forensic Sci.Rev 12, Movig KLL, Mathijssen MPM, Nagel PHA, van Egmond T., de Gier J.J., Leukens HGM and Egberts ACG (2004). Psychoactive substance and the risk of motor vehicle accidents. Accident Analysis and Prevention 36, Jones CG, Swift W, Donelly NJ and Weatherburn DJ (2007) Correlates of driving under the influence of cannabis. Drug and alcohol dependence 88, Método oficial para la determinación de alcoholemia. Boletín del Consejo del Poder Judicial, 3ªÉpoca. Año XII, 108, García R., Moreno E., Soriano T., Roca I. and Menéndez M. (2002). Screening de drogas de abuso en sangre total mediante inmunoensayo CEDIA, originalmente diseñado para análisis de orina. Aplicación a casos forenses. Rev.Toxicol. 19(3), T.Soriano, C.Jurado, ML.Soria, MP.Gimenez, M. Menéndez, M. Repetto (1997), Aplicación de la extracción en fase sólida a la sistemática analítica toxicológica, Proceedings of the XII Jornadas Toxicológicas Españolas Rev.Toxicol. 14 (2-3), Del Río MC, Gómez J, Sancho M, Alvarez FJ (2002). Alcohol, illicit drugs and medicinal drugs in fatally injured drivers in Spain between 1991 and Forensci Sci. Int. 127, Del Río MC and Álvarez FJ (1996). How benzodiazepines are prescribed in a primary health care setting in Spain. Therapic 51, Del Río MC and Alvarez FJ (2000). Presence of illegal drugs in drivers involved in fatal road traffic accidents in Spain. Drug and Alcohol Dependence, 57, European Monitoring Centre for Drugs and Drug Addiction Annual Report on the State of the Drug Problem in the European Union (2006). European Monitoring Centre for Drugs and Drug Addiction, Lisbon.Available at: Berghaus G., SheerN., Schmidt P., (1995) Effects of cannabis on psychomotor skills and driving performance-a meta analysis of experimental studies. In: Kloeden C.N., McLEan AJ (eds), Alcohol, Drugs and Traffic Safety. University of Adelaide, Adelaide.

5 12. Mura R., Chatelain C., Dumestre V, Gaulier JM, Ghysel MH, Lacroix C, Kergueris MF, Lhermite M, Moulsma M., Pépin G, viccent F, and Kintz P. (2006). Use of drugs of abuse in less than 30-year-old drivers killed in a road crash in France: A spectacular increase for cannabis cocaine and amphetamines. Forensic Sci. Int. 160,