Carbon monoxide-related deaths in a metropolitan county in the USA: an 11-year study

Carbon monoxide (CO) poisoning as a cause of death is well documented in industrialized countries. The objective of this study was to compare demographic data in deaths due to accidents (in fires) and suicides in the same population between 1988 and 1998. Furthermore, the potential effect of a community wide education effort regarding safety in the home was assessed. Postmortem reports were reviewed for all deaths examined at the Office of the Cuyahoga County Coroner in Cleveland, OH, USA. During the study period, there were 209 accidental deaths due to fires in the home (6.5% of all accidents in the home) and 182 CO deaths by suicide (9.8% of all suicides). Demographic characteristics of the two groups differed: while males represented the majority of cases in both groups (55% of accidents, 70% suicides), race specific death rates were higher for whites than blacks (18/100,000 white, 3/100,000 black) in suicides compared with 29/100,000 deaths for blacks and 11/100,000 for whites in accidental cases. Fire deaths were prevalent in the young (0-9 years) and old (>60) whereas in the suicide group the age specific death rate was highest for those over 70 years. The majority of fire deaths occurred in the city of Cleveland but suicides were prevalent in the suburbs. More fire deaths occurred in December than any other month whereas more suicides occurred in April. In 1992, there was a community wide effort to provide free smoke detectors to residents in Cleveland. In 1992, there were 4.2/100,000 fire deaths in the city. This decreased to 0.6/100,000 in 1996, increased to 1.2/100,000 in 1997 followed by a decrease to 0.8/100,000 in 1998. This suggested that the program may have aided in decreasing these types of deaths. Deaths due to fires in the suburbs were <1/100,000 throughout the study period.     

Suicide with inert gases: addendum to Final Exit

Suicide by asphyxiation with a plastic bag placed over the head is a method that has been advocated by right-to-die groups. Recently, such groups have proposed the introduction of helium into the plastic bag as a means of hastening death. Helium is readily available at toy stores, where it is sold in tanks for balloon inflation. It produces asphyxiation by the exclusion of oxygen in enclosed spaces. We report 7 fatalities throughout an 18-month period involving plastic bag suffocation in conjunction with helium use. These fatalities coincide with publication of an update to a popular right-to-die text in which this method is described. Although right-to-die literature was absent from all scenes, this method was not previously observed in our jurisdiction, and the deaths likely reflect exposure to this information. Because of analytical difficulties in testing for helium in biologic specimens, death certification rests on scene investigation.     

A novel histological technique for distinguishing between epithelial cells in forensic casework

There are a number of forensic cases in which the identification of the epithelial cell type from which DNA originated would provide important probative evidence. This study aimed to develop a technique using histological staining of fixed cells to distinguish between skin, buccal and vaginal epithelium. First, 11 different stains were screened on formalin-fixed, wax-embedded cells from five women. Samples were analysed qualitatively by examining staining patterns (colour) and morphology (absence or presence of nuclei). Three of the staining methods – Dane's, Csaba's and Ayoub-Shklar – were successful in distinguishing skin epithelial cells from buccal and vaginal. Second, cells were smeared directly onto slides, fixed with one of five fixatives and stained with one of the three stains mentioned above. Methanol fixation, coupled with the Dane's staining method, specific to keratin, was the only technique that distinguished between all three cell types. Skin cells stained magenta, red and orange and lacked nuclei; buccal cells stained predominantly orange–pink with red nuclei; while vaginal cells stained bright orange with orange nuclei and a blue extracellular hue. This staining pattern in vaginal cells was consistent in samples collected from 50 women aged between 18 and 67. Identification of cell type from unlabelled micrographs by 10 trained observers showed a mean success rate of 95%. The results of this study demonstrate that histological staining may provide forensic scientists with a technique for distinguishing between skin, buccal and vaginal epithelial cells and thus would enable more conclusive analyses when investigating sexual assault cases.