Silva B.S., Vieira D.N., Oliveira M.M.F., Pinho Marques E.G., Monsanto P.V.

Servicos de Toxicologia e Tanatologia, Instituto de Medicina Legal de Coimbra, Largo da Sé Nova, 3000 Coimbra, Portugal

Methods. Blood samples were taken from cadavers whose blood ethanol concentrations were positive. These samples were preserved during 6-8 months, 12-14 months and 24-26 months at -18° C. Sodium fluoride was added to same of them. After those time periods, blood ethanol concentrations were again determined using gas chromatography head space technique.
Results. A decrease in blood ethanol concentrations in both samples (those with sodium fluoride and those without), was noted, chiefly in those whose blood ethanol concentrations were higher. Those changes seem to be independent of the period of the time elapsed.
Conclusions. A tendency for a decrease in blood ethanol concentrations is observed in samples that are subjected to a long period of preservation.