Surveillance of suicide deaths involving gases in Australia using the National Coronial Information System, 2006 to 2017.

BACKGROUND: There have been concerns about the increased use of helium and nitrogen gas as a suicide mechanism in Australia. METHODS: National Coronial Information System data were used to investigate gas-specific suicides in Australia over the period 2006-2017. Characteristics were compared between helium or nitrogen, carbon monoxide and seven other gases. RESULTS: Gas inhalation accounted for 10% (3,103/31,002) of all suicide deaths in Australia between 2006 and 2017. The mean age of individuals who died by suicide was 47.6 years (SD 16.9, R 14-97) and 83.3% were male. The number of gas suicides declined over the study period (IRR=0.96). The fall was associated with a 47% decline in carbon monoxide suicides (IRR=0.93). There was an increase in deaths due to argon (IRR=1.60) and nitrogen (IRR=1.27). Compared to individuals using other non-carbon monoxide gases, individuals who died by suicide from helium or nitrogen were significantly more likely to be older, have a physical illness and/or disability, have contacted a euthanasia group and have accessed instructional material and purchased gas online. CONCLUSIONS: Suicides by carbon monoxide decreased between 2006 and 2017 alongside an increase in argon and nitrogen gas use - particularly among older adults. The ease of access to these gases points to new targets for means restriction. Implications for public health: Identifying the types of gases used in suicide deaths and emerging trends may enable targeted interventions that could potentially reduce access.

Time trends in suicide rates by domestic gas or car exhaust gas inhalation in Japan, 1968-1994.

AIMS: A reduction in the carbon monoxide content of domestic gas and car exhaust gas has been associated with a decrease in gassing suicides in many western countries. In Japan, a reduction in the carbon monoxide content of domestic gas supply began in the early 1970s, and carbon monoxide emissions standards of new passenger cars were significantly strengthened in 1978. However, little is known about the impact of detoxification of these gases on gassing-related suicides in Japan. Therefore, we examined the changing patterns of suicide due to domestic gas or car exhaust gas inhalation by gender and age in Japan between 1968 and 1994. METHODS: Suicide mortality data were obtained from the Vital Statistics of Japan. In this study, age was divided into four groups: 15-24, 25-44, 45-64 and 65+ years. Method of suicide was divided into three groups: domestic gas, car exhaust gas and non-gases. We calculated method-specific age-standardised suicide rates by gender within each of the four age groups. We applied joinpoint regression to the data and quantified the observed changes. RESULTS: Suicide rates by domestic gas, regardless of gender and age, increased from 1968 to the mid-1970s and then decreased sharply. The proportion of all suicides accounted for by domestic gas was comparatively high in the mid-1970s among females aged 15-24 and 25-44 years, while for other gender-age-groups the proportion of domestic gas suicides remained small, even at the peak. For females aged 15-44 years, the decrease in domestic gas suicides appeared to cause a substantial decrease in overall suicides in this gender/age group. Car exhaust gas was a more common method for males, particularly those aged 25-64 years. Car exhaust gas suicide rates for males aged 25-64 years peaked in the mid-1980s, followed by a sharp decrease. CONCLUSIONS: A reduction in the carbon monoxide content of the domestic gas, which began in the early 1970s in Japan, was associated with a decrease in domestic gas suicides for both genders of all ages. Concerning females aged 15-44 years, a decrease in domestic gas suicides caused a substantial decrease in overall suicides in this gender/age group since the proportion of domestic gas suicides among all suicides combined was comparatively large. However, it remains uncertain whether the introduction of catalytic converters in the 1970s in Japan resulted in a reduction of suicides from car exhaust gas inhalation.

Suicide by gassing in Hong Kong 2005-2013: Emerging trends and characteristics of suicide by helium inhalation.

BACKGROUND: Increased use of lethal suicide methods can have a profound impact on overall suicide incidence; the epidemic of suicide by barbecue charcoal gas poisoning in some East Asian countries is a recent example. There have been concerns about recent rises in suicide using gases in some Western countries. METHODS: We investigated suicide by gassing in Hong Kong (2005-2013) using Coroner's files data. The characteristics were compared between suicide by helium inhalation, charcoal gas poisoning, and other methods. RESULTS: About one sixth (1407/8445, 16.7%) of all suicides used gases. Charcoal-burning suicides constituted the majority (97.5%) of them but showed a reduction over the 9-year period (-33%). Helium suicide was not recorded in 2005-2010 but increased from one in 2011 to three in 2012 and 11 in 2013, accounting for 1.2% of all suicides in 2013. Similar to the profile of charcoal-burning suicides, helium suicides were younger and more likely to have debt problem and less likely to receive psychiatric treatment than other suicides. Internet involvement related to the method was found in one third of cases of helium suicide. LIMITATIONS: The small number of helium suicides (n=15) limits the power to examine their characteristics. CONCLUSION: Suicide by charcoal burning showed a downward trend whilst there was an alarming increase in helium suicide in Hong Kong. Public health measures to prevent an epidemic of helium suicide similar to that of charcoal-burning suicide may include close monitoring of trend, responsible media reporting, and restricting online information about and access to this method.

Suicide by gases in England and Wales 2001-2011: evidence of the emergence of new methods of suicide.

BACKGROUND: Increases in suicide deaths by gassing, particularly carbon monoxide poisoning from burning barbecue charcoal, have occurred in many parts of East Asia and resulted in rises in overall suicide rates in some countries. Recent trends in gas poisoning suicides outside Asia have received little attention. METHODS: We analysed suicides by gassing in England and Wales (2001-2011) using national suicide mortality data enhanced by free text searching of information sent by coroners to the Office for National Statistics (ONS). We conducted specific searches for suicides involving barbecue charcoal gas, helium, and hydrogen sulphide. We analysed coroners' records of eight people who used helium as a method of suicide, identified from systematic searches of the records of four coroners. RESULTS: Gassing accounted for 5.2% of suicide deaths in England and Wales during 2001-2011. The number of gas suicides declined from 368 in 2001 to 174 by 2011 (a 53% reduction). The fall was due to a decline in deaths involving car exhaust and other sources of carbon monoxide. There was a rapid rise in deaths due to helium inhalation over the period, from five deaths in the two year period 2001-2002 to 89 in 2010-2011 (a 17-fold increase). There were small rises in deaths involving hydrogen sulphide (0 cases in 2001-2002 versus 14 cases in 2010-2011) and barbecue charcoal gas (1 case in 2001-2002 versus 11 cases in 2010-2011). Compared to individuals using other methods, those suicides adopting new types of gas for suicide were generally younger and from more affluent socioeconomic groups. The corones' records of four of the eight individuals dying by helium inhalation whose records were reviewed showed evidence of Internet involvement in their choice of method. LIMITATIONS: We were not able to identify the source of carbon monoxide (car exhaust or barbecue charcoal) for over 50% of cases. CONCLUSION: Increases in helium inhalation as a method of suicide have partially offset recent decreases in suicide by the use of car exhaust. Public health measures are urgently needed to prevent a potential epidemic rise in the use of helium similar to the recent rises in charcoal burning suicides in East Asia.

The role of the press and the medical community in the epidemic of "mysterious gas poisoning" in the Jordan West Bank.

In March and April 1983, an epidemic of "mysterious gas poisoning" occurred in the Jordan West Bank region, affecting more than 900 persons, predominantly schoolgirls. That both Arabs and Israelis believed there was an etiologic poisonous substance reflected their longstanding conflict. Israeli newspaper reports, opinions by Arab and Israeli physicians, and the emotional climate in Djenin Hospital contributed to the generation and propagation of this belief. The author discusses the specific difficulties he met in investigating the outbreak.

Predictors and outcomes of posttraumatic stress disorder in World War II veterans exposed to mustard gas.

Current posttraumatic stress disorder (PTSD) associated with participation in secret military tests of mustard gas during World War II was assessed in 363 male military veterans who were randomly sampled from a registry developed by the Department of Veterans Affairs. Current prevalence was 32% for full PTSD and 10% for partial PTSD. Prevalence of PTSD varied as a function of risk and protective factors, including volunteering, physical symptoms during the tests, and prohibited disclosure. Prediction of partial PTSD was weaker than prediction of full PTSD. Veterans with full PTSD reported poorer physical health, a higher likelihood of several chronic illnesses and health-related disability, greater functional impairment, and higher likelihood of health care use than those with no PTSD. Veterans with partial PTSD also had poorer outcomes than did veterans with no PTSD in a subset of these domains. There is discussion of the traumatic elements of experimental mustard gas exposure, vulnerability to PTSD, and the relevance of these findings to understanding the broad range of outcomes associated with PTSD.

Casualties from a junior-senior high school during the Persian Gulf War: toxic poisoning or mass hysteria?

Mass hysteria is a bizarre and uncommon epidemic phenomenon. The usual victims are adolescent females and school settings are frequent. The epidemics are characterized by the rapid onset of a constellation of symptoms and signs which resolve quickly in the absence of abnormal laboratory results and physical findings that confirm a specific organic cause. It is common, however, for unexpected laboratory results to cause confusion and promote controversy about suspected etiologies. These outbreaks are often noted to be associated with periods of uncertainty and social stress. We describe an epidemic involving the explosive onset and rapid resolution of a constellation of symptoms that sent 17 seventh and eighth grade students and four teachers to the emergency department of a hospital after an apparent toxic gas exposure. Mildly elevated carboxyhemoglobin levels (for nonsmokers) in some patients raised concern that there had been exposure to excessive levels of carbon monoxide. Although no specific unusual stress could be identified at the school, the event took place 3 1/2 weeks after the beginning of the Persian Gulf War.

Epidemic hysteria in Virginia: the case of the phantom gasser of 1933-1934.

OBJECTIVE: We studied an example of epidemic hysteria occurring outside a closed community and involving fear of being "gassed." The description presented is that of a previously unrecorded case of epidemic hysteria in the state of Virginia during 1933-1934. DATA SOURCES: Data were gathered from contemporary newspaper accounts. CONCLUSION: The case of the Virginia "gasser" is one in a long series of epidemic hysteria incidents during the 20th century, coinciding with heightened awareness of environmental pollution and triggered by imaginary or exaggerated contamination threats. A recommendation is provided on how physicians should approach such episodes.

Mass sociogenic illness by proxy: parentally reported epidemic in an elementary school.

"In a cluster of illness reported among students at an elementary school parents mentioned many signs and symptoms including headache, pallor, dark circles under the eyes, nausea, and vomiting--which they attributed to exposure to recurrent leaks of natural gas at the school. It is likely that the parents spread among themselves the notion of toxic exposure at the school. A questionnaire revealed no spatial clustering, but increased reports of symptoms were related to intense media coverage. A thorough environmental and epidemiological investigation was negative, there being no evidence of a continuing gas leak or other potential causes. At a strictly biological level, the complaints in this reported 'cluster' apparently represented the sporadic occurrence of common childhood illnesses. The possibility of an epidemic from toxic exposure at the school caused intense parental concern and led to a major public health problem. The established term 'mass sociogenic illness' seems inapplicable here because complaints did not come principally from the students and the apparent epidemic illness was not transmitted among them. The term 'mass sociogenic illness by proxy' is proposed to describe this incident, in which transmission in one group (the parents) resulted in reports of an epidemic in another group (students)."

Hanging, firearm, and non-domestic gas suicides among males: a comparative study.

OBJECTIVE: To identify characteristics that could distinguish males who completed suicide by hanging from males who completed suicide by firearms and non-domestic gas, and to suggest suicide prevention strategies targeted at hanging. METHOD: Using the psychological autopsy design, males who used hanging, firearms and non-domestic gas were compared on a range of variables covering social, psychological, and health related factors and aspects of the suicide incident. The sample consisted of 950 males who completed suicide in Queensland, Australia, between 1994 and 1996. RESULTS: Compared with males who used firearms and non-domestic gas, males who used hanging were significantly younger, less likely to have left a suicide note, and more likely to have been diagnosed with a psychotic disorder. Compared with males who used firearms, males who used hanging were significantly more likely to have made prior suicide attempts and have had no physical illness. Compared with males who used non-domestic gas, males who used hanging were significantly more likely to have lived with others, have had prior legal trouble, and have completed suicide at their residence. CONCLUSIONS: The results are discussed in terms of the availability and socio-cultural acceptability of methods. The authors suggest a possible relationship between impulsive traits and method choice. This proposition requires further investigation using alternative methodologies. Some suicide prevention measures targeting hanging suicides are discussed in light of the results.

Psychological epidemic in Hong Kong. I. Epidemiological study.

A total of 413 school students were taken ill with symptoms from an alleged poisonous gas affecting two different geographic locations at the same time and without influencing the residents in the neighbourhood. Symptoms were mainly subjective and almost all were discharged from hospital the same day. Vigorous endeavours by authorities had failed to discover the offending agent. By the use of epidemiological methods, the present study attempted to investigate the nature of and the significant contributing factors related to the episode. The psychological nature was confirmed both by demonstration of positive characteristics as well as by the exclusion of organicity. There was no direct evidence that teachers, headmasters, parents or the mass media had significant influence on the aetiology of the epidemic, albeit their influence could still be an indirect one. Regarding symptom formation, there was evidence that peer influences were more important than an individual's own previous experiences.

Psychological epidemic in Hong Kong. II. Psychological and physiological characteristics of children who were affected.

A double blind retrospective study was carried out on a sample of children who were affected in a mysterious gas poisoning epidemic together with controls drawn from the same school. The dependent measures employed were the Junior Eysenck Personality Questionnaire (JEPQ), a Hypnotic Susceptibility Scale (HSC), Heart Rate (HR) and Skin Potential Response (SPR). A vigilance task was administered during assessment of the latter two variables. The affected children had significantly higher HR together with a marginal increase in SPR. It is proposed that constitutional factors play an important role in determining whether an individual is affected in such an epidemic.

The impact of availability, attraction and lethality of suicide methods on suicide rates in Germany.

Substantial fluctuations have prevailed in both the rate and particular methods of suicide in the Federal Republic of Germany during the past 40 years. The current study examines the extent to which the availability, attraction and lethality of particular methods of suicide affect suicide rates. A close relationship existed in the period from 1949 and 1989 between the peaks of the suicide rate and the percentage of low threshold suicide methods according to De Catanzaro, whereby suicide in this context is understood to mean suicide by shooting or intake of solid, liquid or gaseous poisons. Our hypothetically expected lesser compensation between high and low threshold methods for women was confirmed. Between 1963 and 1976 the rate of suicide committed using domestic gas receded dramatically. Within the same period, however, the rate of suicide committed using other poisons rose accordingly.