Fatal methemoglobinemia in three suicidal sodium nitrite poisonings.

Nitrites are chemicals that are abundant in the environment, widely used as preservatives for meat, and in pharmaceuticals. Volatile products containing nitrites have been used recreationally for the euphoric effect associated with mild hypoxia. Dietary exposure to small amounts is considered harmless. Deaths by ingestion of nitrite salts are not common, but accidental exposure and as suicidal and homicidal agents have been noted. Death is a consequence of oxidation of hemoglobin ferrous (Fe+2 ) iron (Hb) to the ferric (Fe+3 ) form (methemoglobin, MetHb), causing a reduction in the oxygen-carrying capacity of the blood. We report three cases of ingestion of sodium nitrite in two college students (one mildly decomposed) and one adult in early middle age. All of the decedents in these cases developed fatal methemoglobinemia. Sodium nitrite in chemical form was found near the bodies. MetHb was detected in the postmortem blood of each decedent. The MetHb concentrations in the two decedents with a short postmortem interval were less than MetHb concentrations reported in the current literature. The MetHb concentrations reported in the mildly decomposed person were greater than for the other two, but still less than the concentration previously considered lethal. The data from these cases indicate that levels of MetHb can vary widely in fatal cases, and should not be used as the sole criterion for determination of a death caused by sodium nitrite. Following a discussion of the cases, there is a review of the pathophysiology of MetHb production and a current literature review.

Methanol Detected in a Subdural Hematoma as an Embalming Artifact.

Analysis of subdural hematomata has been used to suggest antemortem drug concentrations, with the assumption that materials within the hematoma are less subject to metabolism or degradation during any survival period and postmortem interval. We report the case of an 87-year-old woman whose death had not been reported to the coroner's office until postembalming. Autopsy revealed a traumatic brain injury with subdural hematoma causing a mass effect. Testing of the clot indicated a methanol concentration of 51.8 mg%. No additional analyses were detected. These findings suggest that methanol can be present in a postmortem hematoma sample, yet not represent a poisoning. Our findings also suggest that while the interior of hematomata do not necessarily represent completely "protected space" from postmortem diffusion of some blood constituents, such diffusion is not facile, and analysis may still provide useful indications of antemortem drugs present, if not actual concentrations.