Ethanol is a common psychoactive substance that has been widely consumed in several parts of the world. Gas chromatography (GC) coupled with flame ionisation detector (FID) has often been used for the determination of blood alcohol concentration. The aim of this study was to develop and validate a very simple and reliable HS-GC-FID method for quantitative determination of ethanol in blood sample. Validation of the method was performed by means of Bias, Linearity, LOD, Selectivity, Specificity, Precision, Robustness and Intermediate precision. The method showed an excellent linearity with correlation coefficient (r² = 0.993) was observed in the range from 0.1 to 3.5 mg/mL of ethanol. The percent recovery value were between 91.0 and 109.1 which was with an acceptable percent recovery, The precision (repeatability) was reported as 27 % and intermediate precision of the method resulted in 11% and 1 % for two analysts. The limit of detection (LOD) of ethanol was calculated as 0.099 mg/mL and the selectivity of the method for interferents (methanol and acetaldehyde) was totally selective. Generally, the results obtained confirmed that the method is relatively fast, precise, simple, robust and can be used in routine forensic analyses for the determination of blood alcohol concentration (BAC) at a concentration level greater than 0.13 mg/mL.

A 27-year-old man drunk several large pints and had used some novel psychoactive substances