Quimico Farmaceutico

A m a n d a J. Jenkins, l Barry S. Levine, 1 and John E. Smialek 1

Distribution of Ethanol in Postmortem Liver

REFERENCE: Jenkins, A. J., Levine, B. S., and Smialek, J. E.,
"Distribution of Ethanol in Postmortem Liver," Journal of

Experimental

Forensic Sciences, JFSCA, Vol. 40, No. 4, July 1995, pp. 611--613.
ABSTRACT: The analysis of multiple specimens for ethanol has become anecessary and accepted practice in postmortem forensic toxicology. The correlation between blood and various body fluids has been well documented. However, there is little data on the distribution of ethanol in specimens such as the liver. In postmortem cases where blood is unavailable or contaminated, liver may be used for alcohol and drug analyses. This study reports the analysis, by head space gaschromatography, of heart blood and liver specimens for ethanol from 103 postmortem cases. The average liver/ heart blood ratio in cases with a blood alcohol level (BAC) ->0.04 g/dL was 0.56, SD = 0.30, with a range of 0-1.40. KEYWORDS: toxicology, ethanol, chromatographic analysis

Specimen Collection
Blood and liver specimens were collected from autopsies performed by pathologists of theOffice of the Chief Medical Examiner, State of Maryland. Specimens were collected in 140 mL plastic containers without preservative. The site of blood collection was the heart, but the specific anatomical region was unknown. Similarly, the specific site of liver sampling was not provided by the pathologists. Specimens were refrigerated at 4~ between autopsy and analysis.

Specimen Preparation
0.5 mLof heart blood was diluted with 4.5 mL of a 0.02% internal standard solution (n-propanol) and pipetted into a 23 mL head-space vial. 2 g of liver were homogenized in 18 mL of 0.02% n-propanol and 5 mL of the homogenate pipetted into a head space vial. This resulted in a liver ethanol concentration in units o f grams of ethanol per deciliter of homogenate (g/dL). All specimens were analyzed induplicate. Duplicate analysis of liver homogenates in this laboratory routinely show variation of < 10%.

The analysis of multiple specimens for ethanol has become a necessary and accepted practice in postmortem forensic toxicology laboratories [1]. The analysis of heart blood for ethanol should be conducted on all postmortem cases, whether or not an autopsy is performed. If the blood ethanolconcentration (BAC) is greater than a pre-determined cut-off, such as 0.01 or 0.02 g/dL, then the analysis of additional specimens such as peripheral blood, vitreous humor and urine would be required. There are several reasons for this practice. The analysis of these specimens can provide information about the absorptive status of the individual. This may be important when an estimate of a bloodethanol concentration some time prior to death is required. In addition, vitreous humor and urine, two specimens resistant to the putrefaction process [2], can provide information as to whether the measured BAC resulted from antemortem consumption or postmortem formation. A positive BAC in combination with a negative vitreous humor and urine ethanol concentration would strongly suggest postmortemethanol formation in the blood [3]. In addition, the analysis of multiple specimens enables the identification of contaminated samples. One specimen often analyzed in postmortem forensic toxicological analysis is liver. Recent work has indicated that the analysis of tricyclic antidepressants in liver can assist in the interpretation of blood postmortem tricyclic antidepressant concentrations [4].Surprisingly, little work has been published on the distribution of ethanol in liver. The following is a compilation of data collected to ascertain the distribution of ethanol in liver specimens.

Instrumentation and Chromatographic Conditions
A Perkin-Elmer 8500 gas chromatograph with a flame ionization detector interfaced with a HS-101 head space analyzer was used for ethanol analysis. Specimens...