Skeletal muscle as an alternative specimen for alcohol and drug analysis.

In a random group of medical examiner cases, muscle tissue, as well as blood and vitreous humor, was analyzed for ethyl alcohol, and the results were compared. When the blood concentration was greater than 0.10 g/dL, the muscle to blood ratio was 1.00 or less (average 0.94), and when the blood concentration was less than 0.10 g/dL, this ratio was greater than 1.00 (average 1.48). The author proposes that this ratio is dependent upon the time course of absorption and distribution, as has been observed for vitreous humor, but with a more rapid equilibration. Muscle tissue was also analyzed in another group of cases found to be positive for one or more drugs in blood. The concentrations of the drugs in muscle varied from none detected to 6.5 times those in blood and seemed to be dependent on the time course between ingestion and death, as well as on the nature of the drug. For most common basic drugs, the ratios were often near unity. Muscle is proposed as a useful alternative specimen to postmortem blood.