The most common chemicals that can be ingested and lead to greater than endogenous levels of gamma-hydroxybutyric acid (GHB) in decedents are salts of GHB, gamma-butyrolactone (GBL), and 1,4-butanediol (BD). Results for three deaths involving the ingestion of one or another of these three chemicals, which led to findings of GHB in the decedents, are presented. An extraction procedure that facilitates the quantitation of GHB was developed. If present in the same specimen, both GHB and GBL can be quantitated. To determine the GBL concentration, the specimen is first analyzed for existing GHB, the GBL is then converted to GHB, and the analysis is repeated. The difference between the results in molarity units can yield the GBL concentration. A separate procedure was utilized for estimating concentrations of BD. Specimens analyzed included urine, blood, ocular fluid, brain, and solutions consumed by the decedents prior to death. The procedures were found to be convenient in as much as they are relatively rapid, precise, and economical.

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Cocaine is known to degrade in vivo and in vitro by several hydrolytic mechanisms. A previous study found that the initial amount of cocaine added to plasma could be accounted for by summing the molar concentrations of cocaine's hydrolysis products and the cocaine remaining after hydrolysis. The present study was undertaken to investigate whether or not relationships might exist between such molar concentration sums for different postmortem bodily fluids. Determinations of cocaine, benzoylecgonine, ecgonine methyl ester, and ecgonine were performed using liquid chromatography/mass spectrometry (LC/MS/MS) with heart blood, femoral blood, vitreous humor (VH), and urine (UR). The results demonstrate a strong correlation between blood and VH concentrations (correlation coefficients of 0.88-0.94), weak correlation between the UR and blood concentrations (correlation coefficients of 0.61-0.64), and weak correlation between UR and VH concentrations (correlation coefficient of 0.59). The results demonstrate that ecgonine is a significant hydrolysate with concentrations on the same order of magnitude as benzoylecgonine. The results are consistent with rapid distribution of the parent drug and its hydrolysates in the blood and VH. The strong correlation between the blood and VH demonstrates that VH is an important medium for toxicology testing when attempting to make a determination of cocaine intoxication.

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Limit of detection (LOD) values provide useful indicators for the suitability of an analytical method for samples with low analyte levels. An LOD value can also be used to estimate the false positive probability (p(x >or= LOD)) of a result for a sample with no analyte present, as well as the false negative probability (p(x