Blood Alcohol

• Author: James G. Wigmore
• Pages: 75-103

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blood Alcohol

This chapter is organ ized into f‌ive sections: the methods of blood alcohol

concentration (BAC) analysis, the distribution of alcohol into the various

components of blood (serum, plasma, and red blood cells [RBCs]), the

ef‌fect of storage conditions (e.g., temperature) on BAC, the ef‌fects of the

use of alcohol swabs, and endogenous BACs. The average adult human

has approximately L of whole blood, compared with approximately L

of total body water. The major components of whole blood and their ap-

proximate pe rcentages are as follows:

• Plasma—.%

• RBCs (erythrocy tes)—.%

• White blood cells (leukocytes)—.%

2.01 METHODS OF ANALySIS

Currently, the most common method of forensic analysis of alcohol is

by headspace gas chromatography (GC) (–). Various enzymatic

methods of alcohol analysis are also employed, usually in a hospital set-

ting using antemortem blood (–). The alcohol concentration of

clotted blood for alcohol analysis tends to be lower as there is a loss of

alcohol during the homogenization of the blood (). Other methods

of alcohol analysis include direct injection GC (, ) and high-

pressure liquid chromatography (HPLC) ().

  Wigmore on Alcohol

Reference Number: 

Reference Number: 

, .., . ,  .. . “Improved Recovery and

Stability of Ethanol in Automated Headspace Analysis.” Journal of For-

ensic Sciences, : –,  ( tables,  f‌igures,  references)

Abstract: A study was conducted of the analysis of spiked aqueous, ur ine,

serum, and whole blood samples using a PerkinElmer F- automated

headspace analyzer. The column used wa s a . m stainless steel column

( mm internal diameter [ID]) packed with % Carbowax M on Car-

bopak B. The operating temperatures were heating block ºC, injector

ºC, oven ºC, and detector ºC. n-Propanol was used as an inter-

nal standa rd. The additions of sodium dithionite to prevent acetaldehyde

formation and ammonium sulphate to prevent salting-out ef‌fects were

found to improve recovery and the precision of the ethanol analysis.

In conclusion, we have developed a headspace GC method for deter-

mination of alcohol in blood in which the analyte is st able under ana-

lytical conditions for at least h; the method is accurate, line ar and

extremely precise and sensitive.

Reference Number: 

, ..,  . . “Computer-Aided Headspace Gas Chro-

matography Applied to Blood-Alcohol Analysis: Importance of On-

line Process Control.” Journal of Forensic Sciences, : –,  (

tables,  f‌igures,  references)

Abstract: A headspace GC method used to determine the BAC of arrested

drinki ng drivers in Sweden is described. A volume of . mL of blood was

pipetted and diluted -fold with a solution of n-propanol, as the internal

standard, and sea led into a glass vial. The vial wa s heated to ºC for 

minutes, and the headspace was injected onto three separate columns

(Carbopak C /, Carbopak B /, and % Carbowax M).

HS [headspace]-GC has emerged as the met hod of choice for analy-

sis of ethanol as well as other low molecular weight volatiles in body

f‌luids for research and medicolegal purposes. Th e present method is

similar to many well-established HS- GC techniques described in the

literature. Special precautions must be taken to eliminate th e risk of

mix-up of specimens and to ensure a high degree of quality control of

the day-to-day analytical results . To this end, aliquots of blood are re-