Suicidal Carbon Monoxide Poisoning by Combining Formic Acid and Sulfuric Acid Within a Confined Space

Suicide by inhalation of carbon monoxide produced by mixing formic acid and sulfuric acid within a confined space is a rare method of suicide. This method is similar to the so‐called “detergent suicide” method where an acid‐based detergent is mixed with a sulfur source to produce hydrogen sulfide. Both methods produce a toxic gas that poses significant hazards for death investigators, first responders and bystanders. Carbon monoxide is an odorless gas, while hydrogen sulfide has a characteristic rotten eggs odor, so the risks associated with carbon monoxide are potentially greater due to lack of an important warning signal. While detergent suicides have become increasingly common in the USA, suicide with formic acid and sulfuric acid is rare with only three prior cases being reported. Greater awareness of this method among death investigators is warranted because of the special risks of accidental intoxication by toxic gas and the possibility that this method of suicide will become more common in the future.     

The role of hydrogen cyanide and carbon monoxide in fire casualties: a prospective study

Determinations of blood cyanide and carboxyhemoglobin concentrations were performed in 18 victims found dead in buildings after fires during a 2-year period. The results indicated that 50% of the victims had been exposed to toxic levels of hydrogen cyanide and 90% to toxic levels of carbon monoxide. Lethal concentrations of carbon monoxide were found in 83% of the victims. In one case a lethal blood cyanide but a non-toxic blood carboxyhemoglobin value was found. It is concluded that carbon monoxide appears to be more important than hydrogen cyanide as a toxic agent in the fire atmosphere, but cyanide poisoning without carbon monoxide poisoning may, under certain circumstances, be the cause of death in fire victims.     

Diagnosis of carbon monoxide poisoning following embalming and exhumation

Clots of blood, which were found in the cardiac ventricles at an autopsy of an embalmed corpse, were to analyse for carbon monoxide. It was not possible to determine reliably the CO-Hb-content of the blood clots with the known methods. Therefore a new procedure was developed. Carbon monoxide was released by a solution of nitric acid and determined gas chromatographically by a headspace method. In the same vessel the iron-content of the sample was measured after decomposition with atomic absorption spectrometry. This procedure is especially suitable for samples like putrid or heat-clotted blood.     

Fetal death due to nonlethal maternal carbon monoxide poisoning

Fetal death due to acute carbon monoxide poisoning is rarely reported in the medical literature. Of the eight cases found in literature review, only one documented the fetal carboxyhemoglobin concentration. This paper reports a fetal death due to accidental nonlethal maternal carbon monoxide intoxication in which both maternal and fetal carboxyhemoglobin concentrations were obtained. The corrected carboxyhemoglobin concentration was 61% at the time of death in utero, while the maternal carboxyhemoglobin was measured at 7% after one hour of supplemental oxygen. The authors review the mechanisms of fetal death and emphasize the different carbon monoxide kinetics in the fetal circulation.     

Determination of carbon monoxide in blood by gas chromatography using a thermal conductivity detector

A method is described for the gas chromatographic quantitation of carbon monoxide by means of thermal conductivity detection. Carbon monoxide is released from blood samples as small as 0.02 mL using a unique extraction chamber. The method was compared to a standard gas chromatographic and spectrophotometric method of carbon monoxide quantitation. It was comparable to the former with all samples evaluated and apparently more reliable than the latter with decomposed samples.     

Deaths caused by carbon monoxide poisoning in an open environment (outdoors)

Three deaths as a result of inhalation of carbon monoxide from the exhaust fumes of automobiles are reported. All deaths occurred outside and not in a structure. The individuals were white males, ages 24 to 26 years. Blood carboxyhemoglobin concentrations ranged from 58 (in a decomposing body) to 81%. The three cases illustrate the fact that even in the outdoors death from carbon monoxide inhalation can occur if an individual is in close proximity to a rich source of carbon monoxide.     

Suicidal and accidental carbon monoxide poisonings due to charcoal fires in closed spaces

The number of fatal carbon monoxide poisonings has significantly decreased since the introduction of natural gas. Apart from their occurrence during house fires, accidental and suicidal carbon monoxide poisonings are only rarely seen nowadays. We report on 7 cases of unintentional and intentional fatal carbon monoxide poisoning (CO-Hb concentrations between 56.4% and 74%) due to improper handling of charcoal fires in closed spaces. Autopsy findings and results of the toxicological analysis are presented and discussed.     

Measuring carbon monoxide content in muscles

A method ist described to determine the CO-content in the tissue of muscles. The prepared tissue is pulverized in a swinging mill at the temperature of liquid nitrogen. Parts of the powder are weighed into headspace vessels. Carbon monoxide ist ejected by a formerly described method and measured gaschromatographically. The Fe-content is determined after an acid disintegration by AAS. Acute intoxications lead to higher CO-contents in heart than in periphere muscles. Chronic exposure to carbon monoxide does not produce these differences.     

Hyperuricemia in rats during acute carbon monoxide poisoning

The effect of carbon monoxide (CO) inhalation on plasma levels of uric acid and hypoxanthine in rats was investigated. Exposure to 3% CO caused respiratory arrest within about 2 minutes. The plasma uric acid level of CO-treated rats increased to 157% above that of ether-treated rats. When rats were exposed to 1% or 0.8% CO, the exposure periods until the onset of respiratory arrest were prolonged, and plasma uric acid levels at respiratory arrest were further elevated. Plasma uric acid levels at respiratory arrest increased with prolongation of the exposure periods. Under our experimental conditions, hypoxanthine or xanthine was not detected in plasma of CO-treated rats. These results are discussed in relation to the hyperuricemia in hemorrhagic shock or hypoxemia: CO-induced hyperuricemia can be attributed to the stimulated degradation of adenine nucleotides under tissue anoxia, and thus could be an excellent parameter of tissue anoxia.     

Fatal carbon monoxide poisoning after the detonation of explosives in an underground mine: a case report.

An unusual death caused by carbon monoxide poisoning after the detonation of explosives in an underground mine was investigated by the Office of the Medical Investigator of the State of New Mexico. The 50-year-old miner had 18 years of mining experience but no documented safety training. He collapsed approximately 20 minutes after entering the mine and working at the bottom of the single vertical shaft. The tight confines of the mine shaft hindered rescue personnel from reaching him, and the body was not recovered until 2 days later. The autopsy showed severe coronary artery atherosclerosis with remote and resolving myocardial microinfarcts, as well as the characteristic pink lividity of carbon monoxide poisoning, which was confirmed by laboratory analysis. Detailed investigation of the scene revealed no sources of carbon monoxide other than the explosives. The case represents an uncommon cause of death in mining that may have been avoided through the use of proper safety procedures, and illustrates the importance of recognizing the many sources of carbon monoxide.     

Hepatotoxicity of dichloromethane

We studied hepatotoxicity of dichloromethane using primary cultures of parenchymal cells (hepatocyte) from adult rat livers. The production of carbon monoxide from dichloromethane increased with time, the increased cell number, and the concentration of dichloromethane. However, the carbon monoxide production per hepatocyte decreased with increasing cell density. When dichloromethane was in a high concentration, the metabolism of dichloromethane to carbon monoxide was extensively depressed, total glutamic-oxaloacetic transaminase (GOT) and mitochondrial GOT (m-GOT) levels in the cultured medium were extensively elevated, and the cultured hepatocytes were destroyed by dichloromethane. A case of accidental exposure to dichloromethane which occurred in Japan was also considered, and it is suspected that the inhalation of dichloromethane vapors in a high concentration for many hours may cause hepatotoxicity.     

Death scene evaluation in a case of fatal accidental carbon monoxide toxicity

Exposure of humans to high concentrations of carbon monoxide can result in death, due to the formation of carboxyhaemoglobin (COHb), which impairs the oxygen carrying capacity of the haemoglobin. Carbon monoxide is responsible of a great number of accidental domestic poisonings and deaths throughout the world, particularly in homes that have faulty or poorly vented combustion appliances. A case is reported, in which a 21-year-old woman was found dead, due to carbon monoxide poisoning from a gas water heater, despite the puzzling evidence that the heater has been used for more than 10 years without any problem. An evaluation of the exposure to CO was performed, by measuiring the rate of production of CO from the heater, and using the Coburn-Forster-Kane equation to describe the kinetics of the poisoning process. The death was attributed to an accidental poisoning from carbon monoxide due to a sum of unfortunate circumstances.     

Fire and suicide: a three-year study of self-immolation deaths.

Thirty-two self-immolation deaths by fire, representing about 1% of suicides, occurred in the province of Ontario (population 9 million), Canada, from 1986 through 1988. The victims, mostly male (male/female ratio, 26:6), were between 21 and 71 years old (mean age, 38 years). Although the scene of self-immolation was usually familiar to the deceased, some chose remote locations. Eleven were found dead in motor vehicles. An accelerant, usually gasoline, was used in most cases. Many of these individuals had, at some time, indicated their intent to commit suicide, a few by self-immolation, but only about half had a diagnosed psychiatric illness. Most of the victims had a reason to kill themselves, but the factors that motivated them to chose self-immolation by fire were uncertain. Fourteen individuals died in hospitals from severe burn complications. The remainder were found dead at the scene. The postmortem findings of soot in the airway and elevated carbon monoxide in the blood of most of these victims [the carboxyhemoglobin (COHb) concentration was in one case less than 10%, in ten cases greater than or equal to 10 to 50%, and in seven cases greater than 50%] were helpful in determining that the individuals were not only alive at the time of the fire but also that a significant number died from smoke inhalation and carbon monoxide poisoning. The highest levels of carbon monoxide were observed in victims discovered in motor vehicles.     

Spectrophotometric evaluation of postmortem lividity

Under low ambient temperatures normally bluish postmortem lividity adopts a bright red or pink colour due to resaturation of haemoglobin with O2. The most important differential diagnosis in the presence of pink hypostasis is carbon monoxide poisoning. To answer the question if objective measuring methods allow differentiation of hypostasis with regard to cold exposition or carbon monoxide poisoning, spectrophotometric measurements were performed and the colorimetric measures as well as the spectral reflectance curves of the postmortem lividity were determined. The colorimetric measures CIE-L*a*b* showed similar values for all bright red livores mortis; differentiation between CO intoxication and cold exposition was not possible. Reflectance curves of pink hypostasis after cold storage showed the typical pattern of O2-rich blood with reflectance minima at wavelengths 541 nm and 576 nm and a reflectance maximum at 560 nm. Pink hypostasis because of carbon monoxide poisoning showed a shift of the reflectance maximum toward 555 nm and a flattened curve in all cases with COHb concentrations exceeding 52%, whereas these changes were not regularly observed with lower COHb levels.     

A suicide using a homemade carbon monoxide "death machine"

Deaths related to carbon monoxide (CO) poisoning are common. Most represent accidents and suicides, and most result from CO production via the incomplete combustion of carbon-containing substances. Suicide via CO toxicity is not uncommon and typically involves the use of motor-vehicle exhaust as a source of CO. Presented herein is a case of suicidal CO poisoning in which the CO was produced via a chemical reaction between formic acid and sulfuric acid within a homemade device.     

Suicidal asphyxiation by inhalation of automobile emission without carbon monoxide poisoning

Reported herein is the suicidal asphyxiation of a young man due to exhaustion of oxygen in the interior of a sealed automobile into which the exhaust emissions were diverted. His blood carboxyhemaglobin concentration was less than 5% saturation. The car was equipped with a catalytic converter and when tested, the exhaust carbon monoxide concentration was 0.01%.     

Morphofunctional interaction of adrenal zones in acute lethal carbon monoxide poisoning in people with alcoholic intoxication

Morphological examination of human epinephroses at acute lethal poisoning with carbon monoxide against a background of alcoholic intoxication was done. Acute lethal poisoning with carbon monoxide decreases effect of alcoholic intoxication upon morphofunctional state of epinephroses and disorders characteristics of interzonal interaction. Interaction between zones of one epinephros recedes but interaction between both glands increases.     

甲醛对一氧化碳中毒血检验干扰的研究

目的探讨甲醛对一氧化碳中毒血的检测是否产生干扰,提高一氧化碳中毒鉴定的可靠性。方法采用常用的血中一氧化碳或碳氧血红蛋白饱和度的检测方法对未加甲醛和加甲醛的血样分别进行实验研究。结果甲醛对加热法、氢氧化钠法、氯化钯法、分光光度法等检测方法均可产生不同程度的干扰。结论经福尔马林灌注或固定的检材不宜用于一氧化碳中毒血检测,否则可能导致错误的鉴定结论。     

Unique case of fatal carbon monoxide poisoning in the absence of a combustible fossil fuel

A 37-year-old man died as a result of exposure to carbon monoxide within an apartment. An investigation of the apartment showed no gas appliances or gas supply to the apartment and no evidence of any combustion event to any part of the apartment or roof space. Inhalation of dichloromethane was excluded. Heating to the apartment was found to be via an electrical storage heater, the examination of which revealed that the cast-iron core and insulating material showed evidence of heat damage with significant areas devoid of carbon. This electric storage heater is hypothesized to be the source of carbon for the fatal production of carbon monoxide within the apartment.     

An unusual case of 3 fatal, accidental CO poisoning cases by re-routed ventilation

A case of fatal carbon monoxide poisoning is presented where three members of a family, aged between 23 and 66 years, died while having dinner. After analysing the scene and evaluating the personal circumstances there was no doubt that death was due to accidental carbon monoxide poisoning. The fact that three persons of different ages died almost simultaneously as well as the technical reconstruction appears noteworthy to the authors. Scrutiny of the technical circumstances revealed that the waste air containing carbon monoxide was re-routed because of the oppressively hot weather conditions. The fumes from the stove heating in the living room flowed into the chimney and from there via another pipe into the kitchen oven and finally reached the atmosphere of the kitchen where the three members of the family died.