Impact of paraquat regulation on suicide in South Korea

Restrictions on Pesticides and Deliberate Self-Poisoning in Sri Lanka

Importance

Deliberate self-poisoning using pesticides as a means of suicide is an important public health problem in low- and middle-income countries. Three highly toxic pesticides-dimethoate, fenthion, and paraquat-were removed from the market in Sri Lanka between 2008 and 2011. In 2015, less toxic pesticides (chlorpyrifos, glyphosate, carbofuran, and carbaryl) were restricted. Subsequent outcomes have not been well described.

Objective

To explore the association of pesticide bans with pesticide self-poisonings and in-hospital deaths.

Design, Setting, and Participants

In this cross-sectional study with an interrupted time series design, data were prospectively collected on all patients with deliberate self-poisonings presenting to 10 Sri Lankan hospitals between March 31, 2002, and December 31, 2019, and analyzed by aggregated types of poisoning. The correlates of pesticide bans were estimated within the pesticide group and on self-poisonings within other substance groups. The data analysis was performed between April 1, 2002, and December 31, 2019.

Exposures

Implementation of 2 sets of pesticide bans.

Main Outcomes and Measures

The main outcomes were changes in hospital presentations and in-hospital deaths related to pesticide self-poisoning as measured using segmented Poisson regression.

Results

A total of 79 780 patients (median [IQR] age, 24 [18-34] years; 50.1% male) with self-poisoning from all causes were admitted to the study hospitals, with 29 389 poisonings (36.8%) due to pesticides. A total of 2859 patients died, 2084 (72.9%) of whom had ingested a pesticide. The first restrictions that targeted acutely toxic, highly hazardous pesticides were associated with an abrupt and sustained decline of the proportion of poisonings with pesticides (rate ratio [RR], 0.85; 95% CI, 0.78-0.92) over the study period and increases in poisonings with medications (RR, 1.11; 95% CI, 1.02-1.21) and household and industrial chemicals (RR, 1.20; 95% CI, 1.05-1.36). The overall case fatality of pesticides significantly decreased (RR, 0.33; 95% CI, 0.26-0.42) following the implementation of the 2008 to 2011 restrictions of highly hazardous pesticides. Following the 2015 restrictions of low-toxicity pesticides, hospitalizations were unchanged, and the number of deaths increased (RR, 1.98; 95% CI, 1.39-2.83).

Conclusions and Relevance

These findings support the restriction of acutely toxic pesticides in resource-poor countries to help reduce hospitalization for and deaths from deliberate self-poisonings and caution against arbitrary bans of less toxic pesticides while more toxic pesticides remain available.

"Ad hoc policy decisions" in the news: Media framing analysis of a pesticide import ban in Sri Lanka

Modern agriculture relies on pesticides to maximise outputs. While many highly hazardous pesticides (HHPs) are banned in places like the European Union due to concerns about harm to the environment and human health, their use continues in many low- and middle-income counties (LMICs). Pesticide suicide is a public health problem unique to countries where HHPs are used, and Sri Lanka has successfully implemented several HHP bans as part of a suicide prevention strategy. On 27 April 2021, the Sri Lankan government announced an imminent import ban of all fertilizers and pesticides which was later revoked in November 2021. The aim of this article was to explore the media framing of the import ban as it pertained to pesticides. Guided by Entman's typology of frame functions, we analysed newspaper articles from nine Sri Lankan newspapers (N = 102) between 20 April to 31 October 2021. Overall, most framings were supportive of the ban, captured by framings that articulated the ban through a health, environment, and organic farming narrative. Framings that foregrounded farmer or industry livelihoods and the pesticide market were primarily adopted to express opposition to the ban. The presence of frames opposing the ban within media articles increased over time during the study period. There was a greater proportion of opposing frames in private newspapers compared to government (78% vs 22%). Many of the articles analysed described the widespread impact of the ban, but only 11% of articles represented the voices of policy end users. This study adds understanding to the ways communication via outlets like mainstream newspapers may shape public support or opposition to pesticide bans in a LMIC. Mass media is an under-recognised factor in policy implementation and this study may inform planning to implement pesticide bans in other countries.

Understanding the Fluctuations in Korea's Suicide Rates: A Change-Point Analysis and Interrupted Time Series Analysis

BACKGROUND

Korea has witnessed significant fluctuations in its suicide rates in recent decades, which may be related to modifications in its death registration system. This study aimed to explore the structural shifts in suicide trends, as well as accidental and ill-defined deaths in Korea, and to analyze the patterns of these changes.

METHODS

We analyzed age-adjusted death rates for suicides, deaths due to transport accidents, falls, drowning, fire-related incidents, poisonings, other external causes, and ill-defined deaths in Korea from 1997 to 2021. We identified change-points using the 'breakpoints' function from the 'strucchange' package and conducted interrupted time series analyses to assess trends before and after these change-points.

RESULTS

Korea's suicide rates had three change-points in February 2003, September 2008, and June 2012, characterized by stair-step changes, with level jumps at the 2003 and 2008 change-points and a sharp decline at the 2012 change-point. Notably, the 2003 and 2008 spikes roughly coincided with modifications to the death ascertainment process. The trend in suicide rates showed a downward slope within the 2003-2008 and 2008-2012 periods. Furthermore, ill-defined deaths and most accidental deaths decreased rapidly through several change-points in the early and mid-2000s.

CONCLUSION

The marked fluctuations in Korea's suicide rate during the 2000s may be largely attributed to improvements in suicide classification, with potential implications beyond socio-economic factors. These findings suggest that the actual prevalence of suicides in Korea in the 2000s might have been considerably higher than officially reported.

A potential mechanism clue to the periodic storm from microglia activation and progressive neuron damage induced by paraquat exposure

Paraquat (PQ), is characterized by neurotoxicity, which increases the potential risk of Parkinson's disease (PD) exposure in the long-term and low doses. Triggering microglia activation and neuroinflammation is deemed an early event resulting in PD. However, the underlying pathogenesis of PD by PQ is not clear yet. In this article, C57BL/6J mice treated with PQ could successfully act out Parkinson-like. In addition, we observed the fluorescence intensity enhancement of Iba-1 activated microglia with released pro-inflammatory, all ahead of both the damage of dopaminergic neurons in the substantia nigra and corpus striatum of the brain. Surprisingly, the injection of minocycline before PQ for many hours not only can effectively improve the neurobehavioral symptoms of mice but inhibit the activation of microglia and the release of pro-inflammatory substances, even controlling the gradual damage and loss of neurons. A further mechanism of minocycline hampered the expression levels of key signaling proteins PI3K, PDK1, p-AKT, and CD11b (the receptor of microglia membrane recognition), while a large number of inflammatory factors. Our results suggested that the CD11b/PI3K/NOX2 pathway may be a clue that microglia-mediated inflammatory responses and neuronal damage in a PQ-induced abnormal behavior Parkinson-like mouse.

Evaluation of a national clinical programme for the management of self-harm in hospital emergency departments: impact on patient outcomes and the provision of care

BACKGROUND

Emergency departments are important points of intervention, to reduce the risk of further self-harm and suicide. A national programme to standardise the management of people presenting to the emergency department with self-harm and suicidal ideation (NCPSHI) was introduced in Ireland in 2014. The aim of this study was to evaluate the impact of the NCPSHI on patient outcomes and provision of care.

METHODS

Data on self-harm presentations were obtained from the National Self-Harm Registry Ireland from 2012 to 2017. The impacts of the NCPSHI on study outcomes (3-month self-harm repetition, biopsychosocial assessment provision, admission, post-discharge referral, and self-discharge) were examined at an individual and aggregate (hospital) level, using a before and after study design and interrupted time series analyses, respectively. The 15 hospitals that implemented the programme by January 2015 (of a total of 24 between 2015 and 2017) were included in the analyses.

RESULTS

There were 31,970 self-harm presentations during the study period. In hospitals with no service for self-harm (n = 4), risk of patients not being assessed reduced from 31.8 to 24.7% following the introduction of the NCPSHI. Mental health referral in this hospital group increased from 42.2 to 59.0% and medical admission decreased from 27.5 to 24.3%. Signs of a reduction in self-harm repetition were observed for this hospital group, from 35.1 to 30.4% among individuals with a history of self-harm, but statistical evidence was weak. In hospitals with a pre-existing liaison psychiatry service (n = 7), risk of self-discharge was lower post-NCPSHI (17.8% vs. 14.8%). In hospitals with liaison nurse(s) pre-NCPSHI (n = 4), medical admission reduced (27.5% vs. 24.3%) and there was an increase in self-harm repetition (from 5.2 to 7.8%. for those without a self-harm history).

CONCLUSION

The NCPSHI was associated with improvements in the provision of care across hospital groups, particularly those with no prior service for self-harm, highlighting the need to consider pre-existing context in implementation planning. Our evaluation emphasises the need for proper resourcing to support the implementation of clinical guidelines on the provision of care for people presenting to hospital with self-harm.

Paraquat induced acute kidney and lung injury with a dramatic response to methylprednisolone: A case report

Background

Paraquat poisoning is one of the leading causes of fatal poisoning in many parts of the world, especially in agricultural countries. Its high toxicity even in small amounts causes rapid damage to multiple organs, especially the kidneys, lungs, and liver, mainly through free radical-mediated injury. As no specific antidote is yet available, early diagnosis and the importance of supportive therapy are critical parts of management. Some evidence suggests a survival benefit from using immunosuppressive drugs.

Case report

This case presentation concerns a 15-year-old boy from a village with a history of herbicide poisoning, later confirmed to be paraquat. Despite supportive therapy her condition continued to deteriorate with features of kidney and lung damage. The patient was then treated with methylprednisolone 500 mg daily for 5 days, along with other supportive care, and has made a remarkable recovery.

Conclusions

High efficacy as an herbicide, availability and low cost make paraquat an easy-to-encounter poison for suicidal or accidental use. Its high fatality calls for urgent and effective strategies to save lives. Methylprednisolone may play a role in its treatment.

Features of fatal pesticide ingestion in South Australia

Pesticides are used to kill, repel or control any animal or plant species which are considered pests, but have also been associated with intentional and unintentional human fatalities. A rapid increase in pesticide suicides was observed during 'The Green Revolution' after pesticides were introduced into low- and middle-income rural households without appropriate guidelines for safe use and storage. While national pesticide bans have contributed to a significant decrease in pesticide-related suicides, such cases still comprise a large proportion of all suicides around the world. The aim of the current study was to provide a profile of pesticide suicides in a high-income country as a point of comparison against studies from low- and middle-income countries. Statistical analyses were performed using R (version 4.2.3). Over the 20-year study period, there were a low, yet consistent number of pesticide suicides which were most common among males over the age of 40. Paraquat and methomyl pesticides collectively contributed to almost half (48.8%) of all fatalities. Consistent with the literature, such cases often occurred with little premeditation in response to an acute emotional crisis. While interpretation of autopsy findings was mostly limited, there were some pesticides that demonstrated findings consisted with previously reported characteristics (e.g., gastroesophageal erosions with paraquat). Given the high proportion of cases where paraquat and methomyl pesticides were implicated, it may be appropriate to review the availability and accessibility of such compounds to reduce the occurrence of pesticide suicides in South Australia and potentially the wider Australian population.

Impact of pesticide regulations on mortality from suicide by pesticide in China: an interrupted time series analysis

Background

Pesticide bans and regulatory restrictions have been shown to be effective strategies for preventing suicide in several countries. Suicide and suicide by pesticides have decreased significantly in China over the past two decades. However, whether the reduction was associated with pesticide regulation is unknown.

Methods

The monthly data on suicide and suicide by pesticide from 2006 to 2018 were obtained from China's Disease Surveillance Point (DSP) system. Information on China's pesticide regulations since 1970 was obtained from Pesticide Action Network International (PAN International), Joint Meeting on Pesticide Management Highly Hazardous Pesticides (JMPM HHP) lists, the website of the Ministry of Agriculture of China, Pesticide Information Network of China, and the Wan Fang database. Change point detection and policy analysis were combined to identify the time of any trend change breakpoint of suicide and suicide by pesticide. Interrupted time series analysis was used to investigate the pre- and post-breakpoint trends of monthly standardized rates in suicide and suicide by pesticide.

Results

The standardized pesticide suicide rate decreased by 60.5% from 6.50 in 2006 to 2.56 per 100,000 in 2018. Larger declines were evident among people in urban areas (67.3%), female individuals (63.5%), and people aged 15-44 years (68.1%). The effect of policies banning highly hazardous organophosphorus pesticides (HHOP) [rate ratio (RR) = 0.993, 95% CIs (0.991-0.994)] in December 2008 and stopping domestic sales and use of paraquat aqueous solution (RR = 0.992, 95% CIs: 0.990-0.994) in July 2016 were more pronounced than regulating the paraquat-related products (RR = 1.003, 95% CIs: 1.002-1.004) in April 2012.

Conclusion

Declines in suicide by pesticide in China occurred contemporaneously with regulatory bans and restrictions implemented on several pesticides, particularly in urban areas, among female individuals, and the relatively low age profile. These findings indicate the potential influence of these bans on trends of suicide by pesticides.

Contributions of the life expectancy gap reduction between urban and rural areas to the increase in overall life expectancy in South Korea from 2000 to 2019

BACKGROUND

This study aimed to quantify the contribution of narrowing the life expectancy gap between urban and rural areas to the overall life expectancy at birth in Korea and examine the age and death cause-specific contribution to changes in the life expectancy gap between urban and rural areas.

METHODS

We used the registration population and death statistics from Statistics Korea from 2000 to 2019. Assuming two hypothetical scenarios, namely, the same age-specific mortality change rate in urban and rural areas and a 20% faster decline than the observed decline rate in rural areas, we compared the increase in life expectancy with the actual increase. Changes in the life expectancy gap between urban and rural areas were decomposed into age- and cause-specific contributions.

RESULTS

Rural disadvantages of life expectancy were evident. However, life expectancies in rural areas increased more rapidly than in urban areas. Life expectancy would have increased 0.3-0.5 less if the decline rate of age-specific mortality in small-to-middle urban and rural areas were the same as that of large urban areas. Life expectancy would have increased 0.7-0.9 years further if the decline rate of age-specific mortality in small-to-middle urban and rural areas had been 20% higher. The age groups 15-39 and 40-64, and chronic diseases, such as neoplasms and diseases of the digestive system, and external causes significantly contributed to narrowing the life expectancy gap between urban and rural areas.

CONCLUSION

Pro-health equity interventions would be a good strategy to reduce the life expectancy gap and increase overall life expectancy, particularly in societies where life expectancies have already increased.

Surveillance of pesticide poisoning in an East and a West Malaysian hospital: characteristics of pesticide poisoning and the early impact of a national Paraquat ban

BACKGROUND

Previous studies have shown that pesticide bans were associated with reduced fatal pesticide self-poisoning cases in high, and low-and-middle-income countries. We aimed to investigate the characteristics of pesticide poisoning patients admitted to two Malaysian hospitals and the early impact of the national paraquat ban implemented on 1st January 2020 in a culturally heterogenous South-East-Asian upper-middle-income setting.

METHODS

Data were collected from an East (Bintulu) and a West (Ipoh) Malaysian hospital medical records in 2015-2021 and 2018-2021, respectively. Logistic regression analyses were conducted to investigate the association of aspects such as socio-demographic and clinical characteristics, paraquat ban with the types of pesticides involved (paraquat versus non-paraquat versus unknown) ,and the outcomes (fatal versus non-fatal).

RESULTS

From the study sample of 212 pesticide poisoning patients aged 15 years or above, the majority were self-poisoning cases (75.5%) with a disproportionate over-representation of Indian ethnic minority (44.8%). Most pesticide poisoning cases had socio-environmental stressors (62.30%). The commonest stressors were domestic interpersonal conflicts (61.36%). 42.15% of pesticide poisoning survivors had a psychiatric diagnosis. Paraquat poisoning accounted for 31.6% of all patients and 66.7% of fatalities. Case fatality was positively associated with male gender, current suicidal intent, and paraquat poisoning. After the paraquat ban, the proportion of pesticide poisoning cases using paraquat decreased from 35.8 to 24.0%, and the overall case-fatality dropped slightly from 21.2 to 17.3%.

CONCLUSIONS

Socio-environmental stressors in specific domestic interpersonal conflicts, seemed more prominent in pesticide poisoning compared to psychiatric diagnosis. Paraquat accounted for the majority of pesticide-associated deaths occurring in hospitals in the study areas. There was preliminary evidence that the 2020 paraquat ban led to a fall in case fatality from pesticide poisoning.

Child and adolescent mortality associated with pesticide toxicity in Cape Town, South Africa, 2010-2019: a retrospective case review

BACKGROUND

Poisoning of children after exposure to pesticides is a major public health concern, particularly in countries with poorer urban populations, such as South Africa. This may stem from the illegal distribution and domestic use of street pesticides, which are highly hazardous agricultural pesticides. The aim of this study was to profile paediatric deaths due to acute pesticide poisoning in the west-metropole of Cape Town, South Africa; to identify whether the active ingredients were highly hazardous pesticides according to the FAO and WHO; and to inform policy and public health interventions to prevent future exposures and mortality.

METHODS

A retrospective and descriptive analysis of forensic post-mortem records (2010 to 2019) was conducted to identify cases of paediatric deaths (< 18 years old) in the west metropole of Cape Town, involving pesticide poisoning admitted to the Salt River mortuary (one out of 16 mortuaries in the Western Cape province). Demographic, circumstantial, autopsy, and toxicological information was captured. Descriptive statistics, together with chi-square tests, Fisher's probability tests, and Mann-Whitney U tests were used to analyse the data.

RESULTS

In total, 54 paediatric pesticide deaths were identified, including 22 (40.7%) males and 32 (59.3%) females, out of 5,181 paediatric unnatural deaths admitted over the 10-year period. The median age of the decedents was 8.3 years (range: 1 day to 17.9 years), with the majority under five years (42.6%) or between 15 and 18 years old (40.7%). All incidents occurred in peri-urban areas of Cape Town, with most individuals being admitted to hospital (88.9%) for a median survival time of 4.8 h. Toxicological analysis was requested in 50 cases (92.6%) with the organophosphate pesticides terbufos (n = 29), methamidophos (n = 2) and diazinon (n = 2) detected most frequently. Adolescent (15-18 years) suicides (29.6%) and accidental child deaths (< 4 years) (18.5%) were common.

CONCLUSIONS

Terbufos and methamidophos are highly hazardous pesticide (HHP) active ingredients registered in South Africa for agricultural uses, yet commonly sold as street pesticides for domestic use in lower socioeconomic areas. Reducing access and availability of toxic pesticides, especially through the illegal selling of street pesticides, and providing low toxic alternatives to poorer communities, may support mortality reduction initiatives. Mortality and toxicology data provide important, often overlooked, surveillance tools for informing policy and public health interventions to reduce toxic pesticide harm in local communities.

Suicides by pesticide ingestion in Pakistan and the impact of pesticide regulation

INTRODUCTION

Suicide is a major public health problem in Pakistan, accounting to approximately 19,331 deaths every year. Many are due to consumption of acutely toxic pesticides; however, there is a lack of national suicide data, limiting knowledge and potential for intervention. In this paper, we aimed to review the literature on pesticide self-poisoning in Pakistan to identify the most problematic pesticides in relation to national pesticide regulations.

METHODS

Information on the currently registered and banned pesticides was obtained from Ministry of National Food Security and Research while data on pesticide import and use was extracted from FAOSTAT. We searched the following sources for articles and research papers on poisoning in Pakistan: Cumulative Index to Nursing and Allied Health (CINAHL), Google Scholar, Applied Social Sciences Index and Abstracts (ASSIA), Excerpta Medica (EMBASE), National Library of Medicine's MEDLINE (PUBMED), PS102YCHINFO and Pakmedinet.com using the search terms 'self-poisoning', 'deliberate self-harm', 'suicide', 'methods and means of suicide', 'organophosphate', 'wheat pill', 'aluminium phosphide', 'acute poisoning', OR 'pesticides', AND 'Pakistan'.

RESULTS

As of May 2021, 382 pesticide active ingredients (substances) were registered in Pakistan, of which five were WHO hazard class Ia (extremely hazardous) and 17 WHO hazard class Ib (highly hazardous). Twenty-six pesticides, four formulations, and seven non-registered pesticides had been banned, of which two were WHO class Ia and five Ib. We identified 106 hospital-level studies of poisoning conducted in Pakistan, of which 23 did not mention self-poisoning cases and one reported no suicidal poisoning cases. We found no community or forensic medicine studies. Of 52,323 poisoning cases identified in these papers, 24,546 [47%] were due to pesticides. The most commonly identified pesticide classes were organophosphorus (OP) insecticides (13,816 cases, 56%) and the fumigant aluminium phosphide (3 g 56% tablets, often termed 'wheat pills'; 686 cases, 2.7%). Few studies identified the particular pesticides involved or the resulting case fatality.

CONCLUSION

We found pesticide poisoning to be a major cause of poisoning in Pakistan, with OP insecticides and the fumigant aluminium phosphide the main pesticides identified. Withdrawal of Class I pesticides (as proposed to occur nationally in 2022) and high concentration aluminium phosphide tablets should rapidly reduce suicidal deaths by reducing the case fatality for low-intention poisoning cases. National cause of death data and forensic toxicology laboratory data identifying the pesticides responsible for deaths will be important to assess impacts of the proposed national ban.

Effect of pesticide ban on suicide trend - a 20-year study from a tertiary care center in Central Kerala from 2001 to 2020

Introduction: We assessed the effect of the pesticide regulations implemented in 2011 on suicide trend in Kerala state of India.Materials and methods: Data were collected from case records of suicide autopsies done in a single tertiary care hospital in Thrissur district of Kerala in 2001-2020. Linear trends in overall suicide rates were identified using joinpoint regression analysis. We used Poisson regression models to estimate the annual expected number of suicides in 2011-2020 and calculated the rate ratios between the observed number of suicide and that expected according to the linear pre-ban suicide trend (2005-2010).Results: There were a total of 14,593 suicide autopsies (2501 pesticide autopsies) in 2001-2020. Carbofuran was the commonest pesticide identified, followed by quinalphos, zinc phosphide, and chlorpyrifos. In 2011-2020, overall suicide rates were 22%-48% and pesticide suicide rates were 20%-55% lower than those expected according to pre-ban suicide trends (2005-2010), with the only exception of a 16% higher-than-expected pesticide suicide rate in 2011. There was no change in trend in hanging suicides.Conclusion: Lower-than-expected overall and pesticide suicide rates were found in Thrissur district after the 2011 bans of pesticides in Kerala, with no evidence of means replacement to hanging.

Acute fungicide self-poisoning - a prospective case series

BACKGROUND

Pesticide self-poisoning is a global clinical and public health problem. While self-poisoning with insecticides and herbicides has been extensively studied, there is minimal literature on acute fungicide self-poisoning. We aimed to study the clinical course and outcome of fungicide self-poisoned patients recruited to a prospective cohort in Sri Lanka.

METHODS

We conducted a prospective study of patients presenting with fungicide self-poisoning to nine hospitals in Sri Lanka between 2002 and 2020. Patients were enrolled by clinical research assistants, with clinical outcomes being recorded at regular review for each patient.

RESULTS

We identified 337 cases of self-poisoning with fungicides (alcohol as only co-ingestant), including 28 different fungicides across 5 different fungicide classes. Median time from ingestion to examination was 3.1 (1.8-5.7) h. Nearly all presented to hospital fully conscious (GCS 15, 15-15)- only 27 patients (8.0%) presented with reduced GCS (<15) and only 2 (0.6%) had GCS 3/15. Most patients (333/337, 98.8%) made a full recovery, of whom only eight (2.37%) required intubation and ventilation. Four patients died (case fatality rate: 1.2%; 95% CI 0.0-23.4) after ingestion of edifenphos (n = 2), propamocarb and pyraclostrobin.

CONCLUSION

Fungicide self-poisoning appears to be less hazardous than insecticide or herbicide self-poisoning, with a substantially lower case fatality in the same cohort. Edifenphos is an exception to this 'less toxic' rule; as a WHO Class Ib highly hazardous pesticide, we recommend its withdrawal from, and replacement in, global agricultural practice. Propamocarb should be listed in the WHO hazard classification as propamocarb hydrochloride to reflect the higher toxicity of the common agricultural formulation. Pyraclostrobin currently has no WHO classification; one is urgently required now that its ingestion has now been linked the death of a patient. Additional prospective clinical data on fungicide self-poisoning is required to expand knowledge on the effects of these diverse compounds.

Pesticide use, agricultural outputs, and pesticide poisoning deaths in Japan

OBJECTIVE

Although pesticide poisonings occur worldwide, most high-income countries have not been severely affected. Japan is a key exception, with pesticide suicides becoming a major public health concern in the 1980s. We here report the epidemiology of lethal pesticide poisoning in Japan in relation to its pesticide regulation and agricultural output.

METHODS

We obtained data on pesticide registration and sales from the Japan Plant Protection Association's annual Pesticide Handbook, National Food and Agricultural Materials Inspection Center, and Food and Agriculture Organization of the United Nations. Data on deaths due to pesticide poisoning and population were obtained from Vital Statistics of Japan. We reviewed the registration status and hazard classification of pesticides in Japan and analysed the relationships between the use/sales, pesticides fatalities, and agricultural output.

RESULTS

Five hundred and twenty-nine pesticide active ingredients are currently registered in Japan, including four WHO hazard class IB organophosphorus and carbamate insecticides. Paraquat was registered in 1962 as a liquid SL20 formulation. In 1986, restrictions were imposed on its sale/use and a 4.3% paraquat ion/4.1% diquat ion combination product registered by ICI. There were 221 pesticide poisoning fatalities in 2019, down from 2648 in 1986, a 92% reduction over 33 years. Self-poisoning was responsible for most pesticide deaths in both 1985 (2013/2476, 81.3%) and 2019 (146/221, 66.1%). Pesticide poisoning made up 8.6% of all suicides in 1985, down to 0.7% in 2019. Unintentional pesticide poisoning deaths also all fell by 83.8%, from 463 to 75. These reductions were associated with reduced sales of both OP/carbamate insecticides and paraquat/diquat but no apparent change in agricultural output across a broad range of crops.

CONCLUSIONS

Reduced use of highly hazardous pesticides and lowered concentration formulations in Japan were associated with major decreases in all deaths from pesticide poisoning and the proportion of all suicides due to pesticide ingestion.

Nationwide population-based study of poisoning-induced out-of-hospital cardiac arrest in South Korea

OBJECTIVE

To evaluate the characteristics of poisoning-induced out-of-hospital cardiac arrest (pOHCA) and the factors influencing survival to discharge and good neurological outcomes using a nationwide, population-based database.

DESIGN

Nationwide, retrospective, population-based cohort study.

SETTING AND PARTICIPANTS

This study included adult patients who had experienced pOHCA and those who had not (non-pOHCA patients) in South Korea from January 2008 to December 2018.

OUTCOME MEASURES

The primary outcome was survival to discharge, and the secondary outcome was a good neurological outcome.

METHODS

The basic characteristics of pOHCA and non-pOHCA patients were analysed by descriptive analysis. Logistic regression analysis was conducted for related variables, including pOHCA.

RESULTS

A total of 173 190 patients were included, and 3582 patients (2.1%) were in the pOHCA group. Some of the pOHCA patients were young (58.2±17.8 vs 69.0±15.5, p<0.001), a few of their cardiac arrests were witnessed (12.8% vs 45.1%, p<0.001), a few were resuscitated by bystanders (8.2% vs 14.8%, p<0.001) and they had low shockable rhythm rates (1.2% vs 8.8%, p<0.001). They showed significantly lower survival to discharge and poorer neurological outcomes than non-pOHCA patients (survival to discharge, 3.7% vs 6.2%, p<0.001; good neurological outcomes, 1.3% vs 3.2%, p<0.001). There were no significant differences between pOHCA and non-pOHCA patients in terms of the adjusted ORs for survival to discharge (adjusted OR 0.608; 95% CI 0.86 to 1.27) and good neurological outcomes (adjusted OR 1.03; 95% CI 0.73 to 1.42).

CONCLUSION

This study shows that apparent aetiology of OHCA caused by poison, did not influence survival to discharge and good neurological outcomes. Furthermore, pOHCA occurs in younger patients and has fewer witnesses and shockable rhythms. pOHCA did not influence survival to discharge and good neurological outcomes. Also, pesticides and gases were the most frequent substances causing pOHCA in South Korea.

Impact of Pesticides on Human Health in the Last Six Years in Brazil

Every year, Brazil intensifies its activity in agriculture and, as a result, it has become one of the biggest consumers of pesticides in the world. The high rate of these substances raises environmental and human health concerns. Therefore, we collected papers from PubMed, Scopus, Scielo, and Web of Science databases, from 2015 to 2021. After a blind selection using the software Rayyan QCRI by two authors, 51 studies were included. Researchers from the South and the Southeast Brazilian regions contributed to most publications, from areas that concentrate agricultural commodity complexes. Among the pesticides described in the studies, insecticides, herbicides, and fungicides were the most frequent. The articles reported multiple toxic effects, particularly in rural workers. The results obtained can be used to direct policies to reduce the use of pesticides, and to protect the health of the population.

Evaluation of the impact and implementation of a national clinical programme for the management of self-harm in hospital emergency departments: study protocol for a natural experiment

BACKGROUND

A National Clinical Programme for the Management of Hospital-Presenting Self-Harm (NCP-SH) was introduced in Ireland in 2014. This involved the development of a model of care to standardise the management of self-harm in emergency departments, to be delivered by dedicated clinical nurse specialists. The core components of the programme were to: ensure an empathic and timely response, conduct a biopsychosocial assessment, involve family members in assessment and discharge planning, and provide a bridge to next care. The overall aim of the programme was to reduce the rate of repeat self-harm. This multistage study will evaluate the impact of the NCP-SH on hospital-presenting self-harm and to identify determinants influencing its implementation.

METHODS

Employing a sequential mixed methods design, the first stage will use data from the National Self-Harm Registry Ireland to examine the impact of the NCP-SH on self-harm repetition, along with other aspects of care, including provision of psychosocial assessments and changes in admissions and postdischarge referrals. A cost-effectiveness analysis will assess the cost per repeat self-harm attendance avoided as a result of the NCP-SH. The second stage will identify the influences of implementation fidelity-adherence to the programme's core components-using a combination of document analysis and semistructured interviews with staff of the programme, guided by the Consolidated Framework for Implementation Research.

ETHICS AND DISSEMINATION

This study has received full ethical approval and will run until August 2023. This study is novel in that it will identify important factors influencing successful implementation of complex programmes. It is expected that the findings will provide important learnings for the integration of mental health services in general hospital settings and will be disseminated via peer-review publications along with reports for clinicians and policy-makers.

Association Between Means Restriction of Poison and Method-Specific Suicide Rates

Question

Findings

Meaning

Importance

Objective

Evidence Review

Findings

Conclusions and Relevance

The early impact of paraquat ban on suicide in Taiwan

INTRODUCTION

Pesticide ingestion is a leading method for suicide worldwide. Paraquat is a highly lethal herbicide when ingested. We assessed the impact of the first-stage ban on the import and production of paraquat (from February 2018) on suicides by pesticide poisoning in Taiwan.

METHODS

Suicide data by method (pesticide vs. non-pesticide), pesticide (paraquat vs. non-paraquat), and area/sex/age were extracted from the national cause-of-death data files (2011-2019). Negative binomial regression was used to estimate changes in suicide rates in 2019, compared to the expected rates based on pre-ban linear trends (2011-2017).

RESULTS

The paraquat ban was followed by an estimated 37% (rate ratio [RR] = 0.63, 95% confidence interval [CI] 0.54-0.74) reduction in pesticide suicide rate (190 [95% CI 116-277] fewer suicides) in 2019, mainly due to a 58% (RR = 0.42, 95% CI 0.33-0.54) reduction in paraquat suicides (145 [95% CI 92-213] fewer suicides). Larger absolute reductions in pesticide suicides were found in rural areas, males, and the elderly (aged 65+ years) than their counterparts. Except for a 10% (95% CI 3-18%) reduction in overall suicide rates in the elderly, there was no statistical evidence for a change in non-pesticide and overall (all-method) suicides.

CONCLUSION

The ban on the import and production of paraquat was followed by a fall in whole-population pesticide and paraquat suicides and elderly suicides in Taiwan.

Suicide by poisoning in Pakistan: review of regional trends, toxicity and management of commonly used agents in the past three decades

BACKGROUND

Suicide is one of the leading mental health crises and takes one life every 40 seconds. Four out of every five suicides occur in low- and middle-income countries. Despite religion being a protective factor against suicide, the estimated number of suicides is rapidly increasing in Pakistan.

AIMS

Our review focuses on the trends of suicide and means of self-poisoning in the past three decades, and the management of commonly used poisons.

METHOD

We searched two electronic databases (PubMed and PakMediNet) for published English-language studies describing agents used for suicide in different regions of Pakistan. A total of 46 out of 85 papers (N = 54 747 cases) met our inclusion criteria.

RESULTS

Suicidal behaviour was more common among individuals younger than 30 years. Females comprised 60% of those who attempted suicide in our study sample, although the ratio of completed suicides favoured males. There were regional trends in the choice of agent for overdose. Organophosphate poisoning was reported across the nation, with a predominance of cases from the agricultural belt of South Punjab and interior Sindh. Aluminium phosphide ('wheat pills') was a preferred agent in North Punjab, whereas paraphenylenediamine ('kala pathar') was implicated in deaths by suicide from South Punjab. Urban areas had other means for suicide, including household chemicals, benzodiazepines, kerosene oil and rat poison.

CONCLUSIONS

Urgent steps are needed, including psychoeducational campaigns on mental health and suicide, staff training, medical resources for prompt treatment of self-poisoning and updated governmental policy to regulate pesticide sales.

Suicide by pesticide ingestion in Nepal and the impact of pesticide regulation

BACKGROUND

Nepal recorded 5754 suicides in 2018-19 - a high number for a relatively small country. Over 24% of these suicides were by poisoning, most by ingestion of highly concentrated agricultural pesticides. Nepal has actively regulated pesticides to reduce their health impacts since 2001. We aimed to analyse Nepal's history of pesticide regulation, pesticides responsible for poisonings, and relate them to national suicide rates.

METHODS

Information on pesticide regulation was collected from the Plant Quarantine and Pesticide Management Centre of the Ministry of Agriculture and Livestock Development. National data on suicides from 1980 to 2019 were obtained from the National Statistical Bureau and Nepal Police. Data on the pesticides responsible for self-poisoning and pesticide suicides over time were obtained from a systematic literature review.

RESULTS

As of June 2020, 171 pesticides were registered for use in Nepal, of which one was extremely hazardous (WHO Class Ia), one other highly hazardous (WHO Class Ib), and 71 moderately hazardous (WHO Class II). Twenty-four pesticides have been banned since 2001, with eight (including five WHO Class I compounds) banned in 2019. Although the suicide rate has increased more than twelve-fold since 1980, particularly for hanging (15-fold increase from 1980 to 2018), fatal pesticide self-poisoning has increased by 13-fold. Methyl-parathion is reported to be the key pesticide responsible for pesticide self-poisoning in Nepal, despite being banned in 2006.

CONCLUSION

The full effect of the recent pesticide policy reform in Nepal remains to be seen. Our analysis shows a continuing increase in suicide numbers, despite bans of the most important pesticide in 2006. This may indicate smuggling across the border and the use of the brand name (Metacid) for pesticides in general making it difficult to identify the responsible pesticide. More information is required from forensic toxicology labs that identify the individual compounds found. The effect of recent bans of common suicide pesticides needs to be monitored over the coming years. Evidence from other Asian countries suggests that HHPs bans will lead to a marked reduction in suicides, as well as fewer cases of occupational poisoning.

Suicide rates by occupation in Korea, 1993-2017: the impacts of financial crisis and suicide policy

This study compared the suicide rates among different groups of occupations in Korea and their changes from 1993 through 2017. The suicide rate tended to be low in the high skill occupations except the manager group. The suicide rates showed increases around the financial crises of 1997 and 2008 in most occupations, and the sharpest increase was observed in the managers. The suicide rate in the manager group, which was the lowest among all occupation groups until the mid 2000s, showed the sharpest increase and became the highest since 2012 among all occupation groups. The sustained reduction in suicide rates among the skilled agricultural, forestry and fishery workers in Korea, following the implementation of paraquat control since 2005, shows that means restriction is an effective and essential way for reducing suicides. While more efforts should be put into means restriction, policy makers should focus on changing public perceptions of suicide in order that it would not be accepted as a possible solution for the difficulties in life.

Trends of the incidence and clinical outcomes of suicide-related out-of-hospital cardiac arrest in Korea: A 10-year nationwide observational study

BACKGROUND

The purpose of this study was to evaluate the characteristics and temporal trends of the incidence and survival outcomes of suicide-related out-of-hospital cardiac arrest (OHCA) according to the suicide attempt method during the past decade.

METHODS

A population-based observational study between 2009 and 2018 was conducted. EMS-treated suicide-related OHCAs were classified according to the suicide method into hanging, jumping, poisoning, asphyxia and drowning, and other trauma. The study outcomes were survival to discharge and good neurological outcome. The temporal trends of crude and age- and sex-standardized incidence per 100,000 person-years and standardized rates for outcomes were calculated using direct standardization methods. Predictors of survival to discharge were investigated using multivariable logistic regression.

RESULTS

From 2009 to 2018, the age- and sex-standardized incidence rate of suicide-related OHCA increased from 3.5 to 4.0 cases per 100,000 person-years. Of 21,720 eligible OHCAs, hanging (59.2%) was the most common suicide method, followed by jumping (21.3%), poisoning (14.9%), and asphyxia and drowning (3.5%). Although the standardized rates of survival to hospital discharge improved from 2.9% to 5.1% during the study period, good neurological outcome was not improved (from 0.7% to 1.0%). By suicide method, survival to discharge for the hanging group was increased, and good neurological outcome for the poisoning group showed improvement (both p-for-trend <0.05). Compared with hanging, other suicide methods were negatively associated with survival outcome.

CONCLUSION

The incidence of suicide-related OHCA has increased over the past decade in Korea, and survival outcomes are still very low. New interventions are needed to decrease the incidence and burden of suicide-related OHCAs.

Drug-related female autointoxication registered at a toxicology care center

Objective: To analyze the data on epidemiological records of autointoxication reports registered at a toxicological assistance center. Methods: Exploratory, descriptive, and retrospective study with the analysis of secondary data, conducted from the audit on Toxicological Occurrence Notification and Attendance forms, referring to the period from 2014 to 2018, filed in a toxicological information and assistance center, located in a municipality in southern Brazil. The data obtained were compiled in spreadsheets and analyzed using simple descriptive statistics. Results: 2,942 epidemiological records on women's autointoxication were audited, 72.0% of the total cases in the period studied. The predominant age group was 18 to 29 years old, with 1697 (57.7%) cases. The main toxic agent was medication, and the only agent of intoxication in 2,358 cases (80.1%). Psychotropic drugs accounted for 55.2% (1,593) of the cases, mainly antiepileptic and psychoanalytic drugs. Clonazepam was present in 567 (35.6%) suicide attempts and as the sole agent in 275 (17.3%) of them. In 873 cases (54.8%), mental illness was reported, in 546 (34.3%) previous suicide attempts, and 1,082 (67.9%) continued use of psychotropic medication. The main outcome was hospital discharge in 1,239 cases (77.8%). Conclusion: The study showed an increase in cases of female autointoxication over the period studied. The high percentage of autointoxication with psychotropic medications may be related to the ease of access at home and society's medicalization.

The cost-effectiveness of banning highly hazardous pesticides to prevent suicides due to pesticide self-ingestion across 14 countries: an economic modelling study

BACKGROUND

Reducing suicides is a key Sustainable Development Goal target for improving global health. Highly hazardous pesticides are among the leading causes of death by suicide in low-income and middle-income countries. National bans of acutely toxic highly hazardous pesticides have led to substantial reductions in pesticide-attributable suicides across several countries. This study evaluated the cost-effectiveness of implementing national bans of highly hazardous pesticides to reduce the burden of pesticide suicides.

METHODS

A Markov model was developed to examine the costs and health effects of implementing a national ban of highly hazardous pesticides to prevent suicides due to pesticide self-poisoning, compared with a null comparator. We used WHO cost-effectiveness and strategic planning (WHO-CHOICE) methods to estimate pesticide-attributable suicide rates for 100 years from 2017. Country-specific costs were obtained from the WHO-CHOICE database and denominated in 2017 international dollars (I$), discounted at a 3% annual rate, and health effects were measured in healthy life-years gained (HLYGs). We used a demographic projection model beginning with the country population in the baseline year (2017), split by 1-year age group and sex. Country-specific data on overall suicide rates were obtained for 2017 by age and sex from the Global Burden of Disease Study 2017 Data Resources. The analysis involved 14 countries spanning low-income to high-income settings, and cost-effectiveness ratios were analysed at the country-specific level and aggregated according to country income group and the proportion of suicides due to pesticides.

FINDINGS

Banning highly hazardous pesticides across the 14 countries studied could result in about 28 000 (95% uncertainty interval [UI] 24 000-32 000) fewer suicide deaths each year at an annual cost of I$0·007 per capita (95% UI 0·006-0·008). In the population-standardised results for the base case analysis, national bans produced cost-effectiveness ratios of $94 per HLYG (95% UI 73-123) across low-income and lower-middle-income countries and $237 per HLYG (95% UI 191-303) across upper-middle-income and high-income countries. Bans were more cost-effective in countries where a high proportion of suicides are attributable to pesticide self-poisoning, reaching a cost-effectiveness ratio of $75 per HLYG (95% UI 58-99) in two countries with proportions of more than 30%.

INTERPRETATION

National bans of highly hazardous pesticides are a potentially cost-effective and affordable intervention for reducing suicide deaths in countries with a high burden of suicides attributable to pesticides. However, our study findings are limited by imperfect data and assumptions that could be improved upon by future studies.

FUNDING

WHO.

Changes in method specific suicide following a national pesticide ban in India (2011-2014)

BACKGROUND

This paper investigates whether declines in suicide by insecticide poisoning in India following a national ban on endosulfan in 2011were associated with changes in other methods of suicide and total suicide rates.

METHOD

Method-specific suicide rates between 2001-2014 were calculated using National Crime Records Bureau (NCRB) data by sex, age group and region, with observed rates compared to expected rates for the period post-2011.

RESULTS

There were an estimated 20,146 fewer male and 8,418 fewer female suicides by insecticide poisoning and 5542 fewer male and 2679 fewer female suicides by all other methods following the national endosulfan ban. Contemporaneously, an estimated 92% (23,812) of male and 60% (6,735) of female suicides prevented by insecticide poisoning and all other methods were offset to increases in suicides by hanging and other poisoning. Joinpoint regression indicated a decrease in suicide by insecticide poisoning following the endosulfan ban (annual percentage change (APC) of -12.18 among males and -11.89 among females between 2010-2014) while an increase in male suicide by hanging was noted between 2009-2014 (APC of 7.05).

LIMITATION

Suicide rates based on the NCRB data might be an underestimation of the true suicide rates.

CONCLUSION

Declines in suicide by insecticide poisoning were largely offset by an increase in hanging suicides among males, however, this phenomenon was much less prominent in females and contributed to declines in total female suicide rates. Prevention strategies must continue to focus on pesticide bans with simultaneous attention on hanging prevention policies to reduce overall suicide rates in India.

Aptasensor for paraquat detection by gold nanoparticle colorimetric method

This study aimed to develop an aptasensor for paraquat detection by gold nanoparticles. The specific aptamer for paraquat was selected by using the SELEX process via capillary electrophoresis. Sixty-three aptamer candidates were amplified by asymmetric PCR and screened for paraquat binding using gold nanoparticles (AuNPs). Aggregation of AuNPs was specifically induced by desorption of paraquat binding aptamers from the surface of AuNPs as a result of aptamer-target interaction leading to the color change from red to purple. Aptamer 77F with the following sequence: 5'-AGGCTTACACCTGAAAAGCGGCTTAATTTACACTACTGTAT-3' was selected as a highly specific aptamer for paraquat. The detection limit of paraquat was 0.267 µg/mL by colorimetry and 1.573 µg/mL by the quartz crystal microbalance (QCM) technique. This aptamer showed specificity for paraquat by colorimetry. Dimethyl phophite, diethyl phophite and O,O diethyl thiophosphate potassium salt did not react by colorimetry but, exhibited a weak nonspecific reaction by QCM. This is first time that an aptasensor was used for detection of paraquat based on QCM. However, the aptasensor based on the colorimetric method simply uses a generation of a signal that can be detected by the naked eye. This technique is rapid, low cost easy to use and suitable for on-site detection of herbicide residue.

Sociodemographic characteristics and exposure patterns of pesticide-related cases reported to a poison service center in Brazil between 2012 and 2016

Pesticide poisoning is a significant public health problem responsible for an estimated three million poisoning cases per year and more than 250,000 deaths, most of which occur in underdeveloped countries. We evaluated pesticide exposure cases reported to a toxicological service center in Brazil, between 2012 and 2016. There were 3211 cases of pesticide exposure, with a high prevalence in adults aged 20-39 years (41.2%). Attempted suicide was the leading cause of pesticide cases (48%). Occupational exposure to pesticides of agricultural use was more frequently observed among men. Accidental exposure and attempted suicide were more frequently observed in urban areas while occupational exposure was more prevalent in rural areas. A higher exposure rate was observed among men in counties with higher agricultural activities. Establishing prevalence and cause of pesticide exposure is important to provide subsidy for evidence-based interventions in the field.

A Newly Discovered Humic-Reducing Bacterium, Pseudomonas geniculata PQ01, Isolated From Paddy Soil Promotes Paraquat Anaerobic Transformation

Due to toxicity and persistence of paraquat (a widely used herbicide), eco-friendly remediation approaches to its contamination and effective antidotes to its poisoning have been highly desired and raised increasing concerns. Paraquat degradation was lesser in aerobic soil in comparison with anaerobic soil, and humic-reducing microorganisms (HRMs) play a key role in paraquat anaerobic transformation process. However, the degradation pathways and related mechanisms remain poorly understood. In this study, we investigated the specific interaction mechanisms of the paraquat transformation processes mediated by a humic-reducing strain under anaerobic conditions. A strain of pure culture, designated as PQ01, was successfully isolated from paddy soil using anaerobic enrichment procedure, and identified as Pseudomonas geniculata using phenotypic and phylogenetic analysis. Sucrose, glucose, pyruvate, formic acid, and acetic acid were shown to be favorable electron donors for the reduction of anthrahydroquinone-2,6-disulfonate (AQDS) reduction by PQ01. The strain also had the ability of reducing Fe(III) (hydr)oxides in the presence of sucrose with efficiencies in the order of ferrihydrite > α-FeOOH/γ-FeOOH > γ-Fe₂O₃ > α-Fe₂O₃. In the “PQ01 + paraquat + AQDS + sucrose” system, AQDS reduction and paraquat biotransformation by strain PQ01 occurred simultaneously, and the presence of sucrose significantly enhanced the biotransformation. Specific mechanisms of the electron transfer processes are promoted by both PQ01 and AQDS, and proceed in two aspects: (1) paraquat served as electron donor in the anaerobic reduction of AQDS by strain PQ01; (2) AQDS was reduced by PQ01 anaerobic metabolism to produce AH₂QDS, which can directly react with paraquat under anaerobic conditions to generate a single crystal compound (molecular formula of the unit structure is C₂₆H₂₀N₂O₈S₂), causing the paraquat to decline dramatically. In conclusion, this main mechanism included the microbial reduction of AQDS to AH₂QDS, followed by the abiotic reaction between AH₂QDS and paraquat. This study reported the new characteristics of P. geniculata capable of reducing humics analogs, Fe(III) (hydr)oxides, and paraquat, and proposed a novel electron transformation mechanism of the HRMs’ mediated degradation of organic contaminants.

The Characteristics of Elderly Individuals Who Attempted Suicide by Poisoning: a Nationwide Cross-sectional Study in Korea

BACKGROUND

Suicide among the elderly is a public health concern, as life expectancy is increasing rapidly and suicide rates increase with age. In Korea, self-poisoning is the most common method of attempted suicide. This study aimed to evaluate the characteristics of attempted suicide by self-poisoning among the elderly and to identify risk factors related to the suicide attempts.

METHODS

A cross-sectional observational study was conducted using the Emergency Department-based Injury In-depth Surveillance database in Korea. We included all adult patients visiting the emergency department (ED) who attempted suicide by poisoning between January 2011 and December 2017 and stratified according to age: the elderly (≥ 65 years old) and the younger group. Characteristics and risk factors for attempted suicide by poisoning among the elderly were evaluated using stepwise regression analysis.

RESULTS

Among 25,904 adult patients, 5,164 (19.9%) were classified as elderly. The elderly were more likely to be admitted to hospital and intensive care units, the average ED length of stay was longer, and total mortality was higher than that of the younger group. Male sex, low socioeconomic status, poor physical health, pesticide use, lower alcohol consumption, and fewer prior suicide attempts were found to be risk factors for suicide among the elderly.

CONCLUSION

Self-poisoning among the elderly is associated with poorer clinical outcomes than in younger adult patients. Suicide among the elderly is a potentially preventable public health problem, and with proper identification of the associated risk factors, appropriate multidisciplinary intervention strategies can be implemented.

Quantifying the contributions of age, sex, methods, and urbanicity to the changing suicide rate trends in South Korea, 2001-2016

PURPOSE

Suicide rates in South Korea have been one of the highest in the world. The aim of this study is to quantify the contributions of age, sex, method, and place of residence to the trends of the suicide rates between 2001 and 2016 in South Korea.

METHODS

Using the suicide data obtained from the South Korean National Death Registration data set for the years 2001-2016, a Joinpoint regression analysis was conducted to determine if there was a significant change in the trend of suicide rates. Next, a decomposition analysis method was used to quantify the contributions of age, sex, method, and places of residence to the changes in the suicide rates.

RESULTS

Suicide rates increased between 2001 and 2010, and decreased between 2010 and 2016. Among all the age groups, the 65-79 age group contributed most to the rise (18% in men and 7% in women) and fall (- 15% in men and - 14% in women) of suicide rates. Men contributed much more than women to the increasing trend of suicide rate (63.0% vs. 37.0%). Hanging was the key method of suicide, dominating the ups and downs of the suicide rates. The rates of suicide by pesticide poisoning have been decreasing since 2005 and suicide by charcoal burning continued to increase against a decreasing trend of suicide rate during the period of 2010-2016. The gap of the metropolitan-city-rural suicide rates was narrowing during the period under study, although the rural areas remained to have the highest suicide rates.

CONCLUSION

The ups and downs of suicide rates in South Korea were not uniform across different sociodemographic groups. Age, sex, method, and place of residence contributed differently to the changes in suicide rates. Suicide prevention measures can be more focused on certain age-sex-method-region subgroups.

Emerging pesticides responsible for suicide in rural Sri Lanka following the 2008-2014 pesticide bans

Background

Sri Lanka has reduced its overall suicide rate by 70% over the last two decades through means restriction, through a series of government regulations and bans removing highly hazardous pesticides from agriculture. We aimed to identify the key pesticide(s) now responsible for suicides in rural Sri Lanka to provide data for further pesticide regulation.

Methods

We performed a secondary analysis of data collected prospectively during a cluster randomized controlled trial in the Anuradhapura district of Sri Lanka from 2011 to 16. The identity of pesticides responsible for suicides were sought from medical or judicial medical notes, coroners’ records, and the person’s family. Trend analysis was done using a regression analysis with curve estimation to identify relative importance of key pesticides.

Results

We identified 337 suicidal deaths. Among them, the majority 193 (57.3%) were due to ingestion of pesticides while 82 (24.3%) were due to hanging. A specific pesticide was identified in 105 (54.4%) of the pesticide suicides. Ingestion of carbosulfan or profenofos was responsible for 59 (56.2%) of the suicides with a known pesticide and 17.5% of all suicides. The increasing trend of suicides due to carbosulfan and profenofos over time was statistically significant (R square 0.846, F 16.541, p 0.027).

Conclusion

Ingestion of pesticides remains the most important means of suicides in rural Sri Lanka. The pesticides that were once responsible for most pesticide suicides have now been replaced by carbosulfan and profenofos. Their regulation and replacement in agriculture with less hazardous pesticides will further reduce the incidence of both pesticide and overall suicides in rural Sri Lanka.

Suicide by pesticide poisoning in India: a review of pesticide regulations and their impact on suicide trends

BACKGROUND

Pesticide self-poisoning is a common means of suicide in India. Banning highly hazardous pesticides from agricultural use has been successful in reducing total suicide numbers in several South Asian countries without affecting agricultural output. Here, we describe national and state-level regulation of highly hazardous pesticides and explore how they might relate to suicide rates across India.

METHODS

Information on pesticide regulation was collated from agriculture departments of the central government and all 29 state governments (excluding union territories). National and state-level data on suicides from 1995 to 2015 were obtained from the National Crime Records Bureau (NCRB). We used joinpoint analysis and negative binomial regression to investigate the trends in suicide rates nationally and in Kerala, in view of the robust measures Kerala has taken to restrict a number of HHPs, to identify any effect on suicides.

RESULTS

As of October 2019, 318 pesticides were registered for use in India, of which 18 were extremely (Class Ia) or highly (Class Ib) hazardous according to World Health Organization toxicity criteria. Despite many highly hazardous pesticides still being available, several bans have been implemented during the period studied. In our quantitative analyses we focused on the permanent bans in Kerala in 2005 (of endosulfan) and 2011 (of 14 other pesticides); and nationally in 2011 (of endosulfan). NCRB data indicate that pesticides were used in 441,918 reported suicides in India from 1995 to 2015, 90.3% of which occurred in 11 of the 29 states. There was statistical evidence of lower than expected rates of pesticide suicides (rate ratio [RR] 0.52, 95% CI 0.49-0.54) and total suicides nationally by 2014 (0.90, 0.87-0.93) after the 2011 endosulfan ban. In Kerala, there was a lower than expected rate of pesticide suicides (0.45, 0.42-0.49), but no change to the already decreasing trend in total suicides (1.02, 1.00-1.05) after the 2011 ban of 14 pesticides. The 2005 ban on endosulfan showed a similar effect - lower than expected pesticide suicides (0.79, 0.64-0.99), but no change to the decreasing trend of total suicides (0.97, 0.93-1.02) in 2010. There was no evidence of a decline in agricultural outputs following the bans.

CONCLUSION

Highly hazardous pesticides continue to be used in India and pesticide suicide remains a serious public health problem. However, some pesticide bans do appear to have impacted previous trends in the rates of both pesticide suicides and all suicides. Comprehensive national bans of highly hazardous pesticides could lead to a reduction in suicides across India, in addition to reduced occupational poisoning, with minimal effects on agricultural yield.

Paraquat Poisoning: A Retrospective Study of 55 Patients From a Tertiary Care Center in Southern India

Background

In India the data on paraquat (PQ) poisoning are limited to case reports and small case series. Hence, this study was carried out to understand the clinical features and outcomes of PQ poisoning. We also briefly report the relevant Indian studies on PQ poisoning.

Materials and methods

This was a retrospective case record-based study of PQ poisoning victims admitted over a period of 5 years.

Results

Of the 55 patients included in this study, the in-hospital mortality rate was 72.7%. Acute kidney injury was the most common manifestation. The use of cyclophosphamide did not affect the clinical outcome. Hemoperfusion (HP) was not done for any patient. Pulmonary edema and acute tubular necrosis were the most common histopathological findings.

Conclusion

In India, this is one of the most comprehensive studies of PQ toxicity. Hence, we hope that this information would be of use to clinicians who deal with PQ poisoning.

How to cite this article

Ravichandran R, Amalnath D, Shaha KK, Srinivas BH. Paraquat Poisoning: A Retrospective Study of 55 Patients from a Tertiary Care Center in Southern India. Indian J Crit Care Med 2020;24(3):155–159.

Suicide Overall and Suicide by Pesticide Rates among South Korean Workers: A 15-Year Population-Based Study

Suicide is a major public health concern in South Korea, and self-poisoning by pesticides is one of the common methods of suicide. Pesticide ban policies have been successful for suicide prevention; however, no studies have shown their effect according to occupational groups. The present study analyzed suicide and suicide by pesticide rates among South Korean workers aged 15–64 in 2003–2017, their associations with occupational groups, and the impact of three major economic indices on these factors. Workers in the agriculture, forestry, and fishery industries had relative risks of 5.62 (95% CI: 5.54–5.69) for suicide overall and 25.49 (95% CI: 24.46–26.57) for suicide by pesticide. The real gross domestic product had a positive association with suicide overall only in the last five-year period investigated in this study, and the unemployment rate consistently had a positive association. The economic status and policy for suicide prevention affected suicide and suicide by pesticide rates differently among occupational groups and different time periods. Policy addressing suicidal risk for different occupational groups should be of concern in South Korea.

A Qualitative Exploration of South Korean Emerging Adults' Perspectives on Death and Suicide Through Short Stories

Despite the alarming suicide rate among South Korean emerging adults, relatively little is known about their unfettered perspectives on death and suicide. Therefore, an innovative data collection technique was developed to apprehend the meanings that emerging adults attribute to death and suicide in their explorations of the phenomena through a selection of short stories. A convenience sample (N = 114) responded to a survey in which participants transferred their feelings toward death and suicide to characters or events in the short stories. A qualitative content analysis revealed relatively permissive perspectives toward death and suicide. Negative perspectives on death are associated with societal victimization and positive perspectives with naturalistic fatalism. Positive perspectives on suicide are overwhelmingly rooted in existential, individual choices while negative perspectives focus on societal pressures. These perspectives contribute to illuminating tensions between traditionalist collectivism and contemporary individualism in Korean society that could inform suicide prevention initiatives for emerging adults.

Preparing monoclonal antibodies and developing immunochromatographic strips for paraquat determination in water

Paraquat (PQ) poisoning is a serious threat to human health that leads to pulmonary toxicity, neurotoxicity, and inflammation. Protecting humans from PQ exposure requires the development of rapid analytical methods for on-site detection. Here, two monoclonal antibodies against PQ were generated and an immunochromatographic assay (ICA) was exploited to determine PQ concentrations in water samples. The results showed that the monoclonal antibody 1D6 exhibited higher affinity and sensitivity, with an affinity constant of 5.4 × 10⁸ mol/L and a limit of detection as low as 0.02 ng/mL. Without sample pretreatment, the developed ICA method provided visible limits of detection ranging from 0.25 to 1 ng/mL, and cut-off limits ranging from 1 to 5 ng/mL, where average recoveries were between 83.15% ± 1.9% and 94.49% ± 2.45% with a coefficient of variation ranging from 1.40% to 7.37%. Importantly, these observations were consistent with liquid chromatography tandem mass spectrometry. These data and results suggested that the ICA method was a reliable, portable, and high-throughput method for determining PQ residues in water samples.

Suicide Means Used by the Older Adults in Rural China: A Comparison Between Those Using Pesticides and Other Means

BACKGROUND

The most frequently used means of committing suicide was pesticide poisoning in rural China, yet little is known about the characteristics and risk factors for suicides committed with pesticides compared to those committed via other means in older adults.

METHODS

The participants were 242 older adults (aged 60 or older) who had committed suicide in the rural areas of 3 provinces (Shandong, Hunan, and Guangxi) in China. This study was conducted using the psychological autopsy (PA) method.

RESULTS

In univariate analyses, no statistically significant differences were found between those who committed suicide with pesticide or with other means in terms of demographic and clinical variables except age, prevalence of mental disorders, suicidal intent, number of recent life events, social support, hopelessness, impulsivity, and depressive symptoms (P > .05); age, history of suicide attempts, having pesticides available at home, the total number of life events, and the number of long-term life events were significantly different (P < .05) between the 2 groups. In multivariate logistic regression model, the factors associated with committing suicide with pesticides were the availability of pesticides at home (odds ratio [OR] = 3.48, 95% confidence interval [CI]: 1.99-6.08) and the number of long-term life events (OR = 0.87, 95% CI: 0.78-0.97).

CONCLUSION

The older adults who committed suicide by pesticides and those using other means are probably the same population. The main determinant of choosing pesticides as suicide means was likely the availability of pesticides at home. Suicide risk among older adults might be reduced by placing appropriate restrictions on access to pesticides.

How many premature deaths from pesticide suicide have occurred since the agricultural Green Revolution?

Introduction: The agricultural Green Revolution in the 1950s and 60s is thought to have averted many deaths from famine. However, it also introduced highly hazardous pesticides such as parathion and endrin into poor rural communities that were totally unequipped to store or use them safely. Pesticide self-poisoning rapidly became one of the two most common global means of suicide. Thus far, no attempt has been made to enumerate the total number of deaths that have occurred subsequent to the Green Revolution.Objective: To calculate plausible estimates for the total global number of pesticide suicides that have occurred since 1960.Methods: We performed a literature review on Medline and Embase databases to July 2019 to find papers that reported national or global numbers of pesticide suicides. We restricted our search to papers published in English. We used the search terms: pesticide) OR insecticide) OR paraquat) OR organophosphate) OR organophosphorus) OR agrochemical) AND suicide) OR "") OR deliberate) AND poison in all fields. These searches identified 2,144 papers; a further 8 citations were added through the searching of reference lists and our own paper collections. 2,136 papers were excluded as they contained no data on pesticide suicide, or were case reports, case series, or related to specific socio-demographic groups, or were non-human studies. This left 16 papers giving country specific or global pesticide suicide data.Long-term national trend in pesticide suicides: We found studies from one low- and middle-income country (Sri Lanka) that recorded long-term trends in suicide throughout the Green Revolution. These data showed a steady increase in suicides from 1960 to the early 1970s, with a more rapid increase from 1979 to 1984. The number of suicides plateaued until 1995, when they started a steady almost linear decrease that has continued at least until 2015. We used the Sri Lankan epidemiology as a model of the incidence of pesticide suicides in other low- and middle-income countries. Data from Bangladesh suggested that the decrease might have started in 2002.Estimating global numbers since 1960: Starting from a conservative estimate of zero deaths in 1960, the best estimate of the total global burden of pesticide suicides from 1960 to 2018 is 14,272,105 or 14,936,000 (depending on whether a fall in incidence began in 1995 or 2002), with a plausible range of 9,859,667 to 17,303,333 deaths. These are likely underestimates because suicide is illegal in many countries, and most pesticide suicides occur in poor rural areas without effective death registration systems.Conclusions: Pesticide self-poisoning has been a major clinical and public health problem in rural Asia for decades, while being long ignored. Most pesticide suicides are relatively impulsive with little planning: in the absence of highly hazardous pesticides, many people would have survived their suicidal impulse, gone on to find support amongst family, community, and health services, and lived a full life. Pesticide suicides must therefore be considered a category 4 occupation condition following Schilling's classification - if they had not been brought into rural communities for agricultural use, pesticide suicides would not have occurred. Preventing these deaths should be a global public health priority.

Paraquat Degradation From Contaminated Environments: Current Achievements and Perspectives

Paraquat herbicide has served over five decades to control annual and perennial weeds. Despite agricultural benefits, its toxicity to terrestrial and aquatic environments raises serious concerns. Paraquat cannot rapidly degrade in the environment and is adsorbed in clay lattices that require urgent environmental remediation. Advanced oxidation processes (AOPs) and bioaugmentation techniques have been developed for this purpose. Among various techniques, bioremediation is a cost-effective and eco-friendly approach for pesticide-polluted soils. Though several paraquat-degrading microorganisms have been isolated and characterized, studies about degradation pathways, related functional enzymes and genes are indispensable. This review encircles paraquat removal from contaminated environments through adsorption, photocatalyst degradation, AOPs and microbial degradation. To provide in-depth knowledge, the potential role of paraquat degrading microorganisms in contaminated environments is described as well.

Age, period, cohort trends of suicide in Japan and Korea (1986-2015): A tale of two countries

Japan and South Korea have among the highest suicide rates in the world. However, the age, gender, and time trends in each country differ substantially. Age-Period-Cohort (APC) analysis of suicide rates was conducted to better understand these differences. Using age- and gender-specific data on suicide between 1986 and 2015 in Japan and Korea, we implemented APC analysis to decompose the country-specific trends into age, calendar period, and birth cohort effects. APC analysis revealed three trends: (1) there was a sharp increase in suicide around retirement age in Korea but not in Japan (age effect); (2) there was a dramatic increase in suicide during the three decades of observation in Korea (period effect) whereas rates were more stable in Japan; and (3) the post-War generation in Japan (including baby boomer) had lower rates of suicide compared to generations born before 1916 or after 1961 (birth cohort effect), whereas suicide rate has increased linearly in each generation in Korea. Although Japan & Korea share high suicide rates, our APC analysis suggests divergent causes underlying these trends. Japanese suicide rates plateaued among the cohorts who experienced the post-War rapid economic growth (women born in 1951-1956 and men born in 1916-1961) (birth cohort effect) due to a strong social safety net for this cohort, while suicide rates in Korea continue to rise with each generation and is particularly elevated in post-retirement age. Japan and Korea need to pay more attention to suicide prevention in more recent birth cohorts.

Implementation and outcomes of suicide-prevention strategies by restricting access to lethal suicide methods in Korea

For more than 10 years, the suicide rate in South Korea has been the highest among members of the Organization for Economic Cooperation and Development. Suicide-prevention strategies, such as restricting access to lethal suicide methods, have been implemented in Korea. In this paper, we discuss suicide-prevention strategies that restrict access to the five leading methods for committing suicide: pesticide ingestion, inhalation of charcoal fumes, jumping from heights, placing oneself in front of moving subway trains, and hanging oneself by the neck. Of the five suicide-prevention strategies outlined in our study, prohibition of the herbicide paraquat and installation of screen doors were proven to be effective, while others need further assessments. Yet, the overall decline in suicide rate from 31.7 per 100,000 people in 2011 to 27.3 per 100,000 people in 2014 suggests that these suicide-prevention strategies have successfully decreased the suicide rate in Korea.