Effect of combined exposure to carbon monoxide and cyanides in selected forensic cases

Toxic Blood Hydrogen Cyanide Concentration as a Vital Sign of a Deceased Room Fire Victim-Case Report

Carbon monoxide (CO) and hydrogen cyanide (HCN) are two common toxic products of combustion. HCN concentrations of fire victims are not routinely determined in most legal medicine services in Romania. We present the case of a room fire victim in which we evaluated the concentrations of HCN and carboxyhemoglobin (COHb), their contribution to the mechanism of death, and the possibility that HCN concentration can be interpreted as vital sign. COHb was determined by spectrophotometry. HCN was spectrophotometrically determined with ninhydrin in postmortem blood samples after its removal with 20% phosphoric acid and uptake into a solution of potassium carbonate. The presence of ethyl alcohol was determined by gas chromatography. The COHb concentration was 6.15%, while the blood HCN concentration was 1.043 µg × mL⁻¹ and the total HCN was 1.904 µg × ml⁻¹. A blood alcohol content of 4.36 g‰ and a urine alcohol content of 5.88 g‰ were also found. Although the fire produced a considerable amount of soot, and there were signs of inhalation of soot particles, the COHb level cannot be interpreted as a vital sign. Toxic concentrations of HCN and total HCN can be interpreted as a vital sign and indicates a contributive effect of HCN in the mechanism of death.

Manner of Death Determination in Fire Fatalities: 5-Year Autopsy Data of Istanbul City

Death resulting from burns is an important social problem and a frequent accident. However, because approximately 10% of cases are estimated to result from a fire that was deliberately started, all fire-related deaths should be treated as suspicious, and the cause of a fire should be investigated. For the bodies recovered from the scene of a fire, the manner of death could also be suicide or homicide. The objective of this study was to contribute to the clarification of controversial data present in the literature on the manner of death determination of fire-related deaths, through evaluation of autopsy findings of bodies recovered from fires. We reviewed 20,135 autopsies performed in a 5-year period, in Istanbul, as the whole autopsy data of the city and found 133 fire-related deaths. The death scene investigation reports and other judicial documents, autopsy findings, and toxicological analysis results were evaluated to determine the parameters of age, sex, level of the burn, vital signs [red flare; soot in the lower respiratory tract, esophagus, and/or stomach; and screening of carboxyhemoglobin (COHb) levels in the blood], toxicological substances, presence of accelerants, cause of death, and manner of death. The manner of death was determined to be an accident in 98 (73.7%) and homicide in 12 (9%) cases, whereas there was no suicide. In addition, it could not be determined in 23 (17.2%) cases. In accidental deaths, the most frequent cause of death was COHb poisoning with statistically significant blood COHb levels greater than 10%. Further, the presence of soot in the lower respiratory tract, esophagus, and/or stomach and the existence of at least 1 or 2 vital signs together were found to be valid deterministic criteria with statistical significance in terms of identifying the manner of death.

Contribution of forensic autopsy to scene reconstruction in mass fire casualties: a case of alleged arson on a floor consisting of small compartments in a building

A fire is an important cause of mass disasters, involving various forensic issues. Before dawn on an early morning, 16 male visitors in their twenties to sixties were killed in a possibly incendiary fire at a 'private video parlor' consisting of small compartments in a building. The main causes of death as determined by forensic autopsy were acute carbon monoxide (CO) intoxication for all of the 15 found-dead victims, and hypoxic-ischemic encephalopathy following acute CO intoxication for a victim who died in hospital. Burns were mild (<20% of body surface) in most victims, except for three victims found between the entrance and the estimated fire-outbreak site; thus, identification was completed without difficulty, supported by DNA analysis. Blood carboxyhemoglobin saturation (COHb) was higher for victims found dead in the inner area. Blood cyanide levels were sublethal, moderately correlated to COHb, but were higher in victims found around the estimated fire-outbreak site. There was no evidence of thinner, alcohol or drug abuse, or an attack of disease as a possible cause of an accidental fire outbreak. These observations contribute to evidence-based reconstruction of the fire disaster, and suggest how deaths could have been prevented by appropriate disaster measures.

Analysis of 101 Vehicle Fire Fatalities

Vehicle fire fatalities encompass both fire and traffic investigations important for the forensic pathologist. Previous studies have demonstrated the challenges in victim identification, determining cause and manner of death, evaluating the role of collision dynamics, and estimating the excess burden of deaths due to post-collision fire. To address these challenges, the present study analyzed 101 vehicle fire fatalities representing 85 accidents, six suicides, four homicides, two natural deaths and four deaths of undetermined manner. Deliberately set fires in homicides, suicides, and suspicious deaths caused nine deaths. Non-accidental deaths were twice as common in parked vehicles. Of 78 collision fatalities, 46 were occupants of cars, 47 were drivers, and 48 died in collisions involving fixed objects or non-impact rollovers. Occupants of heavy trucks and collisions with light trucks and SUVs had the highest per-collision fatality rates. Frontal and rollover collisions claimed most lives, and rear collisions had the highest fatality rate. Carboxyhemoglobin (COHb) levels were highest in parked cars wherein toxic inhalation occurred prior to fire. In post-collision fires, COHb ranged no higher than 31% saturation and were much lower than in house fires. Potentially survivable blunt force injuries (BFI) and no BFI were present in more than half of charred bodies of post-collision fires. Evidence of inhalation of combustion products correlated imperfectly with severity of BFI, and airway soot deposition was a more sensitive indicator of post-collision viability than COHb. Between 13% and 59% of collision fatalities were due to post-collision fire and not BFI.