Prevalence of ethanol and illicit drugs in road traffic accidents in the centre of Portugal: An eighteen-year update.

This study presents the prevalence of ethanol and illicit drugs in fatal road traffic accident victims in the Centre of Portugal between January 1990 and December 2007. Among the violent deaths, road traffic accidents presented the highest percentage (around 35%; n=3095), but decreasing throughout the years. Accidents were preponderant in males (about 80%; n=2402), between 21 and 30 years-old. Accidents involving drivers (55%; n=1310) were of the most common, being the car the main vehicle (45%), followed by the motorcycle (40%). An alcohol analysis request was present in 50% of the cases (n=1687), but increasing each year. Ethanol concentrations >1.2g/L, the legal limit in Portugal, were found in 55% (n=283) of the cases. Concerning drugs of abuse requests, only 4.4% (n=137) and 17.3% (58 cases) of the cases included the analysis at the Forensic Pathology Department (FPD) and at the Medico-Legal Office (MLO), respectively. Among the road accident cases analysed, 18 were positive, mainly in men (84%), between 21 and 30 years-old; opiates (47.1%; n=8) and cannabinoids (50%; n=4) were the most found, at the FPD and at the MLO, respectively. In conclusion, ethanol was identified as a key factor to traffic accidents, which explains the definition of specific legislation and methods of enforcement to prohibit this form of impairing. Nevertheless, ethanol still remains the psychoactive substance most frequently identified in the blood of divers killed in road-traffic crashes, recommending additional actions of supervision and control.