Fatal Carbon Monoxide Research Articles

Carbon monoxide-related fatalities: A fifteen-year single institution experience.

The winter climate in Delhi is severe, with temperatures dropping below 10°C. As a result, individuals often resort to utilizing diverse heat sources such as electrical heating appliances, coal and gas geysers. Unfortunately, these sources are commonly associated with the emission of carbon monoxide (CO) which can accumulate in inadequately ventilated spaces. Exposure to this noxious gas can lead to acute lethargy and debilitation, leaving individuals in a state of helpless distress. The present study utilized a retrospective descriptive analysis to examine cases of fatal carbon monoxide exposure retrieved from the Department of Forensic Medicine archives at the esteemed All India Institute of Medical Sciences, New Delhi. Autopsy records were thoroughly examined with respect to various parameters including age, gender, seasonality of the incident, circumstances surrounding the death, source of carbon monoxide generation, post mortem observations, as well as toxicological analysis reports. This study entailed an analysis of 56 individuals who fell victim to carbon monoxide poisoning, with a staggering 95% of fatalities occurring during the winter season. The majority of the individuals affected belonged to the age bracket of 21-30 years. The most common sources of carbon monoxide exposure were linked to the use of coal-burning earthen or iron vessels for room heating, as well as structural fires. With the exception of one case, all incidents were accidental in nature. Additionally, nearly all of the victims were discovered in enclosed spaces with heating equipment in close proximity, and evidence of a struggle was noted on the crime scene or with the deceased. The findings of this study indicate that the principal contributor to the inadvertent build-up of lethal concentrations of carbon monoxide gas is the utilization of heating appliances within inadequately ventilated, enclosed spaces. Due to the scentless and non-irritating properties of this gas, individuals who are asleep may be unable to detect its presence in their surroundings, thereby leading to a silent death. To mitigate such risks, the installation of carbon monoxide detectors is crucial. Additionally, it is of utmost importance to raise public awareness regarding the perils associated with using fire pots, coal burning and electrical heating appliances in areas with insufficient ventilation.

The spectrum of presentations of unintentional carbon monoxide poisoning.

Carbon monoxide (CO) is an odourless and tasteless gas which can be produced by the incomplete combustion of carbon-containing fuels. Compared to vehicular CO suicides, unintentional cases (excluding those related to fires) are much less common. Increased education surrounding the risks associated with the accumulation of CO in enclosed spaces has contributed to a reduced incidence of unintentional CO poisonings. However, such cases may remain undetected, particularly in domestic and recreational settings where scene findings are often non-specific. The current study of unintentional CO poisonings in South Australia and the Northern Territory, each with a unique climate (Mediterranean and tropical respectively), demonstrated differences in the circumstances of death. Several cases where individuals used carbon-producing fuel sources for heat, both in domestic and vehicular settings and without adequate ventilation, resulted in fatal outcomes. Less common scenarios involved faults in equipment (e.g. a hot water heater), vehicle faults resulting in the accumulation of fatal levels of CO in enclosed spaces, and inadvertent introduction of CO into a diving oxygen supply in a recreational aquatic setting. In ascertaining the cause of death, other considerations include the potential role of underlying chronic cardiovascular and respiratory disease and age which may increase an individual's susceptibility to CO toxicity. Understanding the wide variety of presentations and contributing factors in cases of fatal CO poisoning including consideration of climate-specific differences in domestic and extra-domestic settings may enable improved detection at autopsy.

Barbecue charcoal burning: an alternative means of carbon monoxide suicide

Intentional carbon monoxide poisoning is most commonly achieved by inhaling exhaust fumes from a vehicle in a confined space. However, there are a small proportion of cases which utilise barbeque (BBQ) charcoal to produce fatal carbon monoxide levels. This method is most prominently observed throughout East/Southeast Asia and such cases demonstrate consistent demographic and socioeconomic trends,1 particularly those in Korea (young males in cars).2 However, suicides utilising this method in other countries occur in lower numbers and exhibit markedly different profiles. The current study was undertaken to analyse rates of charcoal-burning suicides in South Australia (SA) as a point of comparison against existing Asian and European studies. A total of 502 carbon monoxide-related deaths occurred in SA between 2000–2019. Of those, 20 cases (4%) involved burning BBQ charcoal resulting in fatal carbon monoxide poisoning, 18 (90%) of which were suicides. While no significant demographic trends were identified due to limited reporting of nationality, 78% of decedents were male and were found either in the bathroom (n=4), bedroom (n=3) or loungeroom (n=2) of their home address or seated in a vehicle (n=9). While demographic trends were not significant, BBQ charcoal burning appears to be associated with intentional self-harm rather than inadvertent exposure.

Fatal unintentional non-fire related carbon monoxide poisoning: Data from Narrative Verdicts, England and Wales, 1998-2019

Background and Aim: Unintentional non-fire-related (UNFR) carbon monoxide (CO) poisoning continues to cause fatalities. Coroners’ narrative verdicts concerning fatal UNFR CO poisoning in England and Wales, 1998-2019, were collated by the Office for National Statistics. Methods: Search terms related to CO exposure were used to obtain information regarding the circumstances of death. Findings were grouped by location of death, source of CO, and reason or behaviour underlying the exposure. Results: There were 750 deaths (77% male). Annual numbers of deaths decreased over the period studied. Two-thirds (68%) of the deaths occurred in the autumn/winter. Of records with information, 59% of deaths occurred in a dwelling (67% male). Males also predominated in deaths in vehicles (91%) and garages/outbuildings (95%). Of deaths with information, domestic piped gas was the most common source of CO (36%), and the most frequent underlying factor was inadequate ventilation of exhaust gases (39%, 91% male). Conclusion: Despite the decrease in the annual numbers of deaths over the study period, there remains a clear need for measures to raise awareness of the dangers of CO poisoning, especially amongst men working alone in garages/outhouses. Education campaigns and fitting and maintaining CO alarms in high-risk areas should be encouraged. Keywords: carbon monoxide, CO, unintentional poisoning, environmental epidemiology, environmental public health, unintentional death, preventing CO poisoning

Liver as an alternative specimen for carbon monoxide detection when blood is unavailable

Carbon monoxide (CO) is one of the most toxic gases, responsible for a large number of deaths in the cases of smoke and fire burning. CO has the ability to combine reversibly with hemoglobin to form carboxyhemoglobin (HbCO), which denotes its chemical asphyxiant character. This leads to decreased oxygen carrying capacity of hemoglobin. Consequently, the determination of CO concentration and the degree of HbCO saturation in blood are frequently tested in toxicology laboratories. Recently, only the blood is considered the sample of choice for the detection of CO. Different methods for CO detection and estimation in blood have been employed including colorimetric screening, spectrophotometry and gas chromatography (GC). But when blood is not available in fire exposure postmortem cases, it is not possible to conclude the cause of death. Objective of this study is to highlight the significance of liver as specimen of interest in fatal carbon monoxide poisoning in relevance to detection in postmortem specimen of blood. In this study, the authors considered data from one hundred and fifty fire burn cases for carbon monoxide detection. Among these cases, liver and blood were tested simultaneously for CO confirmation. These cases included confirmation of carbon monoxide using colorimetric a technique by palladium chloride micro diffusion assay in which metallic palladium is obtained after reduction of palladium chloride present in impregnated paper strips. The results were only considered positive if the strip develops black color strip with silver glitter. Carbon monoxide/drug-free whole blood was used as the negative control while 12% CO containing whole blood was used as a positive control. One hundred and twenty-one (80.6%) cases were found positive for the presence of carbon monoxide both in blood and liver. Of these, 9.9% cases accounted for carbon monoxide detection only in blood. However, the remaining 9.5% of cases were found negative both for blood as well as liver. Liver was positive for carbon monoxide in approximately 90.5% of the cases under test when the blood was also positive for these samples. As the heme is found both in blood and liver, so there is strong evidence of CO detection in liver. This will be a huge method for forensic investigations when the blood is unavailable but liver is available. This method will also be valuable for an exhumed putrefied postmortem sample when only liver is available.

Double deaths due to domestic carbon monoxide poisoning correlated with medicolegal autopsy and laboratory studies

Carbon monoxide poisoning is one of the most prevalent types of accidental poisoning worldwide, especially in houses and hotels with malfunctioning or badly maintained appliances. Most carbon monoxide poisoning cases remain undetected because of common symptoms of flu and lack of knowledge. Two people died as a result of unintentional carbon monoxide poisoning in the restroom, which we reported. On the next day of Valentine's Day, a boy and a girl, both about 23 years old and healthy students, were discovered dead inside a bathroom in a compromised position. Medicolegal autopsy revealed the Cherry-red discolouration of the skin, mucous membranes, conjunctivae, nail beds, and areas of hypostasis was seen in both the deceased. Further analysis of the crime scene reveals that the bathroom lacks adequate aeration. Suggestive of a carbon monoxide poisoning which was later confirmed in laboratory analysis of post-mortem blood by UV visible spectrophotometry revealed the presence of dangerous levels of carboxyhaemoglobin i.e., 38.27% in male and 36.79% in female. This method of detecting carboxyhaemoglobin in blood is easy and inexpensive. This case serves to increase awareness of fatal carbon monoxide poisoning by gas geysers. Carbon monoxide poisoning is linked to a high death and morbidity rate. Due to the rising usage of gas water heaters in homes, public awareness of the hazards associated with carbon monoxide, with an emphasis on preventive measures at home, is essential for avoidance.

Fatal Unintentional Non-Fire Related Carbon Monoxide Poisoning: Data from Narrative Verdicts in England and Wales, 1998-2019.

Unintentional non-fire related (UNFR) carbon monoxide (CO) poisoning continues to cause fatalities. The narrative verdicts from coroners concerning fatal UNFR CO poisoning in England and Wales, 1998–2019, were collated by the Office for National Statistics. Search terms related to CO exposure were used to obtain information regarding the circumstances of death. Findings were grouped by the location of death, the source of CO, and the reason or behaviour underlying the exposure. There were 750 deaths (77% male). The annual number of deaths decreased over the period studied. Two thirds (68%) of the deaths occurred in the autumn or winter. From the records with information, 59% of deaths occurred within a dwelling (67% male). Males also predominated deaths within vehicles (91%) and garages or outbuildings (95%). From the deaths with information, domestic piped gas was the most common source of CO (36%) and the most frequent underlying factor was inadequate ventilation of exhaust gases (39%, 91% male). Despite the decrease in the annual number of deaths over the study period, there remains a clear need for measures that raise awareness of the dangers of CO poisoning, especially amongst men working alone in garages or outbuildings. Education campaigns and fitting and maintaining CO alarms in high-risk areas should be encouraged.

Emerging Nickel Catalysis in Ketones Synthesis Using Carboxylic Acid Derivatives

AbstractNickel catalysis in cross‐coupling reaction of carboxylic acid derivatives (CADs) with various coupling partners to access ketones has grown steadily in last five decades and substantially contributed to this area. These synthetic protocols have afforded various unique privileges: 1) robust approach to access ketones in a stereo defined manner; 2) reduced byproduct formation; 3) broad substrate scope with high functional group tolerance and 4) avoids direct use of fatal carbon monoxide. Herein, an overview of acyl‐nickel complexes reactivity, major mechanistic pathways in ketones synthesis, rational aspects of nickel catalysis with CADs and highlights of synthetic applications will be described in detail. The main objective of this review is demonstration of historical development of nickel catalysis with CADs to access ketones from year 1970 to 2020 and introductory remarks of current state of work progress in this area.

A second autopsy revealed the silent killer: A case of fatal carbon monoxide poisoning from gas geyser

Carbon Monoxide (CO) is one of the important causes of accidental death in bathroom that occurs frequently due to installation of gas geyser. CO is emitted from a gas geyser due to defect or poor maintenance. Blockage of the exit or ‘flue’ pipe is a common fault, sometimes from bad installation or because it becomes blocked by soot or by birds’ nests. Here, we present the case of 30-year-old female found dead in her bathroom, whose second autopsy unveils the actual cause of death. Liquefied petroleum gas (LPG) or piped natural gas (PNG) are used frequently in gas geyser for heating water in developing countries such as India. CO produces anemic anoxia as well as tissue hypoxia by competing with oxygen for binding sites on oxygen carrying heme proteins like hemoglobin, myoglobin, cytochrome-c oxidase and cytochrome p-450. This case highlights the importance of the second autopsy and role of forensic medicine expert in determining the cause and manner of death so as to guiding police in proper investigation and preventing the harassment of innocent people.

Deaths by poisoning in New Zealand, 2008–2013

Introduction: While a number of developed countries have witnessed a decline in carbon monoxide (CO) deaths and increasing numbers of opioid-related fatalities, it is not known whether these or other trends have occurred in New Zealand. The aim of this study was, therefore, to review deaths due to poisoning in New Zealand, describe the causative substances, and identify any trends.Methods: Retrospective study reviewing New Zealand’s poison-related death findings recorded in the National Coronial Information System (NCIS) database over the 6-year period 2008–2013.Results: We identified 1402 poisoning-related deaths recorded in the NCIS database representing a mortality rate of 5.4 deaths/100,000 population per year. The mortality rate due to poisoning was higher in males (6.96/100,000) than females (3.83/100,000). Fatalities peaked in the 40–50-year age group with the highest proportion of intentional deaths occurring in people aged 80–90 years. Pharmaceuticals accounted for 731 fatalities (52%) and chemicals 431 (31%), with multiple exposures occurring in 399 cases (28.5%). While CO was the leading cause of death throughout the period (n = 303, 21.6%), there was a significant reduction in the rate of CO fatalities from 1.69/100,000 population in 2008 to 0.94/100,000 in 2013 (IRR (95% CI) 2013/2008 0.56 (0.37–0.83)). There was, however, no statistically significant change in either the opioid-related death rate or the total number of deaths. Methadone was the leading pharmaceutical cause of fatality and the third most common cause overall, followed by morphine and codeine, with zopiclone and clozapine equally ranked as the sixth most common cause.Conclusion: While New Zealand has not suffered an “opioid epidemic” and has experienced a significant decline in CO deaths, the overall death rate due to poisoning has remained high. The development of accessible, timely, and relevant toxicovigilance systems would support the early implementation of interventions to reduce the leading causes of fatal poisoning.

Cost effectiveness of residential carbon monoxide alarms

While residential carbon monoxide (CO) alarms are now required in a majority of states, the cost effectiveness of the devices is unknown. This analysis was performed to determine the degree of prevention efficacy necessary from home carbon monoxide alarms for their expense to be cost-effective. Data regarding numbers of individuals affected in the United States annually from accidental, non-fire, residential non-fatal and fatal carbon monoxide poisoning were obtained from published literature. Federal governmental estimates of societal costs associated with medical care, lost wages and earnings, value of pain and suffering, and value of a statistical life were applied. The cost of uniform residential carbon monoxide alarm installation was compared to those societal costs in order to calculate what degree of efficiency makes alarms cost-effective. Societal costs for accidental, non-fire, residential CO poisoning are approximately $3.47 billion annually. With an estimated cost of $348 million annually for alarms, prevention of greater than 10% of residential CO poisoning costs must be achieved in order for alarms to be cost-effective. While the true effectiveness of residential carbon monoxide alarms has yet to be determined, current state legislation requiring residential installation of CO alarms is probably cost-effective. .

Ruthenium-Catalyzed Urea Synthesis by N-H Activation of Amines.

Activation of the N-H bond of amines by a ruthenium pincer complex operating via "amine-amide" metal-ligand cooperation is demonstrated. Catalytic formyl C-H activation of N,N-dimethylformamide (DMF) is observed in situ, which resulted in the formation of CO and dimethylamine. The scope of this new mode of bond activation is extended to the synthesis of urea derivatives from amines using DMF as a carbon monoxide (CO) surrogate. This catalytic protocol allows the synthesis of simple and functionalized urea derivatives with liberation of hydrogen, devoid of any stoichiometric activating reagents, and avoids the direct use of fatal CO. The catalytic carbonylation occurred at low temperature to provide the formamide; a formamide intermediate was isolated. The consecutive addition of different amines provided unsymmetrical urea compounds. The reactions are proposed to proceed via N-H activation of amines followed by CO insertion from DMF and with liberation of dihydrogen.

Carbon monoxide-related fatalities: A 60-year single institution experience

ObjectiveThough carbon monoxide (CO) poisonings account currently for a relatively small percentage of total non-natural deaths in Europe, they represent a serious public health burden and significant component of avoidable mortality in many countries. Our aim was to investigate long-term trends and to determine epidemiologic characteristics of the CO-related deaths in the Czech Republic, recorded at the Department of Forensic Medicine in Hradec Králové. MethodsThis was an autopsy-based single-centre retrospective cohort study of all fatalities caused by CO poisoning over six decades (1947–2006). All data were numerically evaluated and processed using NCSS 10 Statistical Software. Statistical significance was defined as a p-value less than 0.05. ResultsA total of 1233 CO-related deaths were identified for inclusion in the study. The manner of death was ranked in order as follows: 45% accidental poisoning, 40% suicidal poisoning, 1% homicidal poisoning, 14% remained undetermined. There were slightly more male victims (59%) than female, and the mean age overall was 48 years. The majority of CO-related fatalities were attributed to coal gas inhalation, with the remainder being from inhaled motor vehicle exhaust fumes, inhaled fire smoke, and other combustion sources such as charcoal, gas and wood-burning appliances. The mean blood carboxyhemoglobin (COHb) level was 66%. A positive blood ethanol concentration was measured in 455 (37%) cases examined. Non-intentional poisonings were highly correlated with the winter months. ConclusionThis study shows that the prevalence of CO-related deaths has decreased significantly in the Czech Republic following the widespread detoxification of the domestic gas in the 1990–1995. Our findings suggest that acute ethanol use, poorer socioeconomic position, and inadequate education status about the danger of CO are associated with an increased risk of fatal CO poisoning. Finally, our results demonstrate the continued value of the autopsy in monitoring global public health security issues and socioeconomic situation. Further similar large-scale studies in different populations are needed to improve the targeting of interventions to the groups with the highest level of risk, and to understand the sources of variation in CO-related mortality.

Fatal carbon monoxide poisoning: A lesson from a retrospective study at All India Institute of Medical Sciences, New Delhi.

Background:Carbon monoxide (CO) is a colorless, odorless, tasteless, and nonirritating gas which makes it difficult for those who are exposed, to detect it, leading to unexpected death. This study was undertaken to see the pattern of fatal CO poisoning and to discuss preventive aspect.Materials and Methods:It was a retrospective descriptive study of fatal CO cases which were autopsied at All India Institute of Medical Sciences, New Delhi, from the year 2010 to the year 2015. The cases were analyzed as per age groups, circumstances of death, season of death, and sources of CO formation.Results and Discussion:The study involved 40 cases of fatal CO poisoning. About 80% of cases were reported in winter months. The maximum cases were reported in the month of January followed by November and December. All the cases except one, died with a source of CO nearby and the person was inside a room or some closed space without ventilation. Source of CO was firepot and electric room heater in most of the cases. Some cases were of CO build inside the car with a running engine. Most of the cases occurred accidentally.Conclusion:Clustering of cases is seen in winters. Poisoning can occur in different ways. The study documents the various possibilities of CO poisoning and advocates community education targeting the high-risk groups and masses, especially during the winter season.

Characterization of Carbon Monoxide Fatalities by Metabolomics

ABSTRACTMetabolite profiling of postmortem blood in carbon monoxide poisoning cases was performed with gas chromatography-mass spectrometry based on metabolomics. All data were processed with an automated mass spectral deconvolution and identification system and the metabolites were characterized using the National Institute of Standards and Technology library. Discriminant analysis was performed and the carbon monoxide-induced biomarkers were determined with a variable importance parameter in the projection plot obtained from partial least square discriminant analysis. This metabolomics approach, including global metabolites profiling, is useful in improving the interpretation of metabolism in carbon monoxide poisoning deaths.

The effect of fatal carbon monoxide poisoning on the equilibria between cell membranes and the electrolyte solution.

The effect of fatal carbon monoxide poisoning on equilibria between cell membranes and surrounding ions was described using a theoretical four-equilibria model. The model was developed to obtain parameters characterizing the interactions between solution ions and erythrocyte or thrombocyte membrane surface. The parameters are the total surface concentrations of both acidic and basic groups C A, C B and their association constants with solution ions K AH, K BOH. These parameters were used to calculate the theoretical values of surface charge density. The model was validated by comparison of these values to experimental data, which were determined from the electrophoretic mobility measurements of the blood cells. The experimental and theoretical surface charge density values agree at pH 2–8, and at higher pH, the deviation was observed.

Fatal unintentional non-fire-related carbon monoxide poisoning: England and Wales, 1979–2012

Context. Unintentional carbon monoxide poisoning remains a significant cause of morbidity and mortality in England and Wales. Methods. Study design: observational case series. Data on fatal carbon monoxide poisoning in England and Wales from 1979 to 2012 were obtained from coroner reports. Data on unintentional non-fire-related carbon monoxide poisoning were extracted and were analysed by year of registration of death, sex, age group, and whether death occurred at a private house, flat, associated garage, or residential caravan (‘home’), or elsewhere. Results and discussion. There were 28,944 carbon monoxide-related deaths, of which 82% were male. Deaths increased from 965 (1979) to 1700 (1987), and then fell to 182 (2012). Of these 2208 (64% male) were recorded as unintentional non-fire-related deaths. Annual numbers of these latter deaths fell from 166 in 1979 to 25 in 2012 (i.e. from 3.37 to 0.44 per million population). Some 81 and 92% of such deaths in males and in females, respectively, occurred at ‘home’. A clear preponderance of male versus female deaths was seen in the 10–19, 20–39 and 40–64 years age groups, with similar numbers of deaths in males and in females in the younger (< 1 and 1–9 year) and higher (65–79 and 80 + years) age groups. A higher proportion of these excess deaths in males occurred outside the deceased's ‘home’ in those aged 10–19, 20–39 and 40–64 years. Conclusion. Deaths from unintentional non-fire-related carbon monoxide poisoning are now much less common in England and Wales than in earlier years, but remain a cause for concern. Installation and proper maintenance of carbon monoxide alarms in dwellings and outhouses, for example, and education not only of the public, but also of health and other professionals as to the danger posed by carbon monoxide could help prevent such deaths.

The Effect of Fatal Carbon Monoxide Poisoning on the Surface Charge of Blood Cells

The objective of this investigation was to evaluate postmortem changes of electric charge of human erythrocytes and thrombocytes after fatal carbon monoxide (CO) poisoning. The surface charge density values were determined on the basis of the electrophoretic mobility measurements of the cells carried out at various pH values of electrolyte solution. The surface charge of erythrocyte membranes after fatal CO poisoning as well as after sudden unexpected death increased compared to the control group in the whole range of experimental pH values. Also, a slight shift of the isoelectric point of erythrocyte membranes to high pH values was observed. The surface charge of thrombocyte membranes after fatal CO poisoning decreased at low pH compared to the control group. However, at high pH, the values increased compared to the control group. The isoelectric point of thrombocyte membranes after fatal CO poisoning was considerably shifted toward low pH values compared to the control group. The observed changes are probably connected with the destruction of blood cell structure.

Occupational carbon monoxide fatalities in the US from unintentional non‐fire related exposures, 1992–2008

To analyze characteristics of, and trends in, work-related carbon monoxide (CO) fatalities in the US. Records of unintentional, non-fire related fatalities from CO exposure were extracted from the Bureau of Labor Statistics' Census of Fatal Occupational Injuries and the Occupational Safety and Health Administration's Integrated Management Information System for years 1992-2008 and analyzed separately. The average number of annual CO fatalities was 22 (standard deviation=8). Fatality rates were highest among workers aged≥65, males, Hispanics, winter months, the Midwest, and the Fishing, Hunting, and Trapping industry subsector. Self-employed workers accounted for 28% of all fatalities. Motor vehicles were the most frequent source of fatal CO exposure, followed by heating systems and generators. CO has been the most frequent cause of occupational fatality due to acute inhalation, and has shown no significant decreasing trend since 1992. The high number of fatalities from motor vehicles warrants further investigation.

Gas geyser – A cause of fatal domestic carbon monoxide poisoning

Carbon monoxide is responsible for a large number of accidental domestic poisoning and deaths throughout the world. Domestic carbon monoxide poisoning is rarely reported in India and remains an under recognized problem. The diagnosis of carbon monoxide poisoning is usually based on autopsy findings, circumstantial evidence and estimation of carboxy-haemoglobin in blood. We report a case of fatal accidental carbon monoxide poisoning in a bathroom where an LPG gas water heater was installed recently. Cherry pink discolouration of the body and organs on autopsy suggested carbon monoxide poisoning. Laboratory analysis of blood by UV visible spectrophotometry revealed presence of dangerous levels of carboxy-haemoglobin. Effective preventive measures can help in bringing down the mortality and morbidity associated with carbon monoxide poisoning.