Asphyxial deaths from the recreational use of nitrous oxide.

The recreational use of nitrous oxide is widespread. Nitrous oxide for recreational use is usually obtained from anesthesia tanks or whipped-cream machine chargers or cans. Twenty previously described deaths associated with recreational nitrous-oxide use describe anesthesia tanks and whipped-cream machine dispensors as a source. Five deaths associated with nitrous oxide use are presented; two involving whipped-cream cannisters as the source, two involving anesthesia tanks, and one involving a racing fuel tank as a source of nitrous oxide. Autopsy findings in our cases were subtle or negative, but usually suggestive of asphyxia. Through a laboratory simulation, we have confirmed that nitrous oxide displaces oxygen in a closed space, which probably leads to asphyxia. A review of the literature, neuropharmacology, and pathophysiology of nitrous oxide use is also presented.     

Public Attitudes About Property Distribution at Death and Intestate Succession Laws in the United States

Intestate succession statutes should reflect the distributive preferences of intestate decedents. To date, these distributive preferences could only be inferred from distributive patterns found in wills. This telephone survey of 750 persons living in Alabama, California, Massachusetts, Ohio, and Texas supplements prior will studies and provides new insights concerning public attitudes about property distribution at death. The distributive preferences of the respondents revealed few significant differences that could be attributed to age, education, income, wealth, or occupational status. Two other important findings of this study suggest that a modern intestacy statute should provide that (1) the surviving spouse inherit the entire estate in preference to the decedent's issue or family of orientation and (2) issue who are in the same generation share equally in the estate.     

Adsorption saturation and chromatographic distortion effects on passive headspace sampling with activated charcoal in fire debris analysis

Distortion of the chromatographic profile obtained for hydrocarbons that have been sampled by adsorption onto activated charcoal is a well-known phenomenon. The work reported here helps to better define the causes of chromatographic profile distortion and offers a potential method to avoid chromatographic distortion in some cases through a subsampling technique. The recovery of hydrocarbons from an equimolar mixture was investigated to determine the influence of hydrocarbon concentration on the molar ratios of recovered components. In a one-quart container, hydrocarbon volumes as small as 24 microL (liquid) were sufficient to saturate the surface area available for adsorption on a 99.0 mm2 square of activated charcoal, resulting in significant distortions in the molar ratio and the chromatographic profile of the recovered hydrocarbons. Passive headspace sampling of a similarly small volume of unweathered gasoline spiked onto carpet padding resulted in a significant distortion of the chromatographic profile. The chromatographic profile of the recovered hydrocarbons closely resembled 75% weathered gasoline. Heating the container spiked with unweathered gasoline to evenly distribute the components and then removing a subsample of the carpet padding to a second container for passive headspace analysis greatly reduced the amount of distortion in the resulting chromatogram.     

Using accumulated degree-days to estimate the postmortem interval from decomposed human remains

Forensic anthropologists often rely on the state of decomposition to estimate the postmortem interval (PMI) in a human remains case. The state of decomposition can provide much information about the PMI, especially when decomposition is treated as a semi-continuous variable and used in conjunction with accumulated-degree-days (ADD). This preliminary study demonstrates a supplemental method of determining the PMI based on scoring decomposition using a point-based system and taking into account temperatures in which the remains were exposed. This project was designed to examine the ways that forensic anthropologists could improve their PMI estimates based on decomposition by using a more quantitative approach. A total of 68 human remains cases with a known date of death were scored for decomposition and a regression equation was calculated to predict ADD from decomposition score. ADD accounts for approximately 80% of the variation in decomposition. This study indicates that decomposition is best modeled as dependent on accumulated temperature, not just time.