The QTrap liquid chromatography-tandem mass spectrometry (LC-MS-MS) by Applied Biosystems was investigated as an adjund to enzyme immunoassay (EIA) for the rapid detection of drugs in blood. Thus, a procedure used to identify drugs in whole blood by EIA was extended to LC-MS-MS analysis. A multiple reaction monitoring (MRM) database of over 100 drugs was constructed to analyze for those drugs commonly observed in postmortem toxicology cases. The QTrap method provided for a scan time of only 2.8 s to produce both an MRM and an enhanced product ion scan. Various validation and developmental steps of the method are presented, as well as a concordance study as a final means of validation. This study was conducted to compare the effectiveness of the QTrap versus conventional extraction methods and gas chromatography-MS for the identification of drugs in 95 postmortem samples. The more than 400 drug results in this study showed 100% concordance between the two techniques.

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The modification of a procedure originally developed for the analysis of ethylene glycol (EG) in serum was also found to permit the simultaneous analysis of gamma-hydroxybutyrate (GHB) in whole blood. The primary feature of the EG procedure was that it employed a water scavenger, 2,2-dimethoxypropane, which reacted with water to produce volatile methanol. Water scavenging is a technique that could be adapted for the analysis of drugs such as GHB as their respective di-t-butyldimethylsilyl derivatives. A close structural analogue of GHB, 2-hydroxy-3-methylbutyric acid, was successfully employed as the internal standard for both EG and GHB. The advantages of the modified procedure are that it is very quick and easy to perform and produces remarkably clean extracts for GHB, especially when compared to other liquid-liquid techniques. We have successfully applied this technique for the analysis of GHB and EG in several postmortem and driving-under-the-influence cases. There is an apparently wide variability between levels of GHB that can be associated with impairment versus those levels that can be associated with death.

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Tall fescue (Festuca arundinacea Schreb.) pastures have been implicated with the occurrence of grass tetany in the eastern U.S.A. Grass tetany problems would probably be reduced if Mg concentration in tall fescue forage were increased. The purpose of this study was to examine the effects of Mg, NPK, and N fertilizers on Mg and other major nutrients in tall fescue grown on a soil already high in Mg. A randomized complete block factorial experiment was conducted for 2 years on an Etowah silt loam (line‐loamy, siliceous, thermic, Typic Paleudults). Tall fescue was fertilized in August of 2 successive years with 0, 84, or 168 kg Mg/ha from MgSO4 . 7H2O and 67‐29‐56 or 134‐58‐112 kg N, P, K/ha from a complete NPK fertilizer; and in December with 0 or 67 kg N/ha from NH4NO3. Forage was harvested five times during the growing season and stockpiled forage was harvested in December. The Mg concentration in forage was increased by Mg and N application and was not affected by NPK rate. Calcium was decreased by N. Potassium was slightly increased by NPK fertilization. Forage Mg was above 0.20% for all sampling dates and K/(Ca + Mg) ratios were below 2.2, so the grass tetany hazard from this forage was probably low. Soil test Mg levels increased in response to Mg fertilization, but soil Mg levels were not affected by NPK or N fertilization. Temperature of the growth period had a greater influence on forage Mg than the fertilization treatments on this soil which was already high in Mg.