Concomitant findings of isopropanol and acetone in biospecimens of decedents known not to have been exposed to the alcohol prompted a study to explain its origins. Mixtures of acetone, ADH, and NADH at pHs 7.3 and 8.8 were incubated at 37 degrees C for varying intervals. Reaction products were then analyzed by headspace GC and assured identification made by GC/MS. It was found that isopropanol is produced by reduction of acetone at pH 7.3 (to a lesser extent at pH 8.8), providing evidence for an alternate metabolic route for acetone. A mechanism for this reduction is proposed. Ranges for isopropanol (in mg/dL or mg/100 g) found in unexposed decedents were: blood 1-29; liver 7-59; brain 2-12; kidney 6-26. Thus, the forensic investigator must interpret isopropanol results cautiously, particularly when low concentrations are found.

Ethanol was determined by gas chromatography in a variety of tissues and body fluids secured at autopsy in 61 cases. The specimens tested included right and left heart blood, femoral blood, pericardial fluid, cerebrospinal fluid, vitreous humor, urine, stomach contents, and brain. Statistical analysis of the cases revealed no significant differences among the various blood sites tested. However, the variations in blood ethanol concentrations among the various sampling sites within each case were as follows: 40 cases showed differences of less than 25%; 16 cases revealed variability between 25% and 50%, 4 cases had differences exceeding 50%. In one case, satisfactory blood analyses could not be accomplished. The larger variances occurred especially in those instances in which stomach alcohol concentration was 0.50% or greater. In one case, the variability amongst the different blood sites exceeded 400% (femoral blood—0.043%, right atrium—0.070%, root of aorta—0.156%); the brain was 0.050%, and the stomach contents was 1.2%. For all 61 cases, variances in blood alcohol content among the different sampling sites in a single cadaver ranged from 1.8 to 428%.

The stability of nortriptyline in aqueous solutions containing various concentrations of formaldehyde was investigated. Amitriptyline, as a reaction product, was determined by gas chromatography/mass spectrometry (GC/MS) in these experiments. Factors that may contribute to this phenomenon, including pH, formaldehyde concentration, and incubation time were evaluated. At 40% (v/v) formaldehyde concentration and pH 4, there was a 68% decrease in nortriptyline concentration along with a concomitant formation of amitriptyline after 24 h. The N-methylated product was responsible for 48% of the total tricyclic drug present. The data also clearly indicate that the formation of amitriptyline is favored at elevated pH.

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very lean flame, rapid closure of the fuel valve produced no flashback. However, if the flame is left running for any length of time under these reduced flow conditions, localized overheating may cause damage to the burner.The 50-mm long-path nitrous oxide-acetylene flame shows a very stable CN emission region for some 20 mm above the burner head. Inert gas sheathing again extends the size and shape of this reducing region.The stability and intensity of the CN emission was measured just above the primary reaction cones with the circular burner. The results with and without nitrogen separation are shown in Figure 2 in comparison with a typical "circular slot" burner (2).Emission intensities for a restricted range of elements, from those which are readily atomized (e.g., sodium) to those which form refractory oxides (e.g., aluminium), were compared for the circular capillary and the circular slot burners operated both with and without flame separation (Table II). Although both the burner heads were of the same diameter and the gas flows were equivalent, the circular capillary burner gives a greater emission signal in all instances. Burner heads may be readily constructed from stainless steel capillary tubing on which stable laminar flames may be maintained. These burners are safer in operation than conventional burners, even with the nitrous oxide-acetylene flame. The method of construction may be used for flame or inert gas shields for these burners.

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