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CPSP Annual Report

In the COVID-19 times, HHPs phase out is more important than ever

I. Intro

September 2020 marks three years since the Centre for Pesticide Suicide Prevention (CPSP) – an initiative of the University of Edinburgh - was launched with support from an Incubator Grant of the Open Philanthropy Project Fund, on the recommendation of GiveWell, USA.
In 2020, CPSP continued its collaborative work in Nepal, India, East and South Africa, supported data collection in Taiwan, and initiated discussions of work in Malaysia and the Caribbean. During these three years, CPSP has grown and developed as a unique research- and evidence-based initiative aiming to minimise pesticide suicide and acute pesticide poisoning by phasing out agricultural use of highly hazardous pesticides (HHP).

Photographs are by Heshani Sothiraj Eddleston and CPSP staff

Photographs are by Heshani Sothiraj Eddleston and CPSP staff

II. Nepal

CPSP's large project in Nepal came to an end in August 2020.

The study took place in ten tertiary care hospitals of nine districts and the two existing forensic science laboratories of Nepal. It aimed to identify the pesticides most important for pesticide suicide and poisoning in the country.

We obtained retrospective data for one year and prospective data for one year on patients diagnosed with pesticide poisoning admitted to participating hospitals. We recorded anonymised unlinked information on demographics, active ingredients and patient outcome from the medical records. The pesticide was identified in the medical notes from the history and referral note.

We also reviewed data on deaths from pesticide poisoning analysed in the two forensic science laboratories of Nepal, namely the Central Police Forensic Science Laboratory (CPFSL) and National Forensic Science Laboratory (NFSL). Data was collected from 14th July 2017 to 20th February 2020 from CPFSL and from 13th April 2017 to 15th July 2020 from NFSL. CPFSL receives samples from more than 70 districts whereas NFSL receives samples from just five districts around Kathmandu. NFSL identifies the exact pesticide ingested while CPFSL usually reports only the pesticide class, with the exact pesticide reported for special cases required by the court.

Medical records of 10 different hospitals (Figure 1) showed that 4148 patients presented to the emergency department of the hospitals with the diagnosis of pesticide poisoning and that 121 died (case fatality 5.2%).
Records from the forensic science laboratories NFSL and CPFSL (Figure 1) reported 242 and 2293 deaths from pesticide poisoning, respectively.

Figure 1: Map of Nepal showing the hospitals and forensic science laboratories from where data were collected. Created for this publication using Microsoft excel and QGIS version 3.12.3.

The most commonly recorded circumstance of poisoning was suicidal (95.8%) followed by accidental (4.2%). There was only one case from occupational poisoning.

Poisoning agents and outcome

Of the 4148 cases with diagnosed pesticide poisoning, in half of the cases (49.3%), the key pesticide involved was not known. Where reported, the top 5 pesticide used in pesticide self-poisoning were zinc phosphide (16.5 %), cypermethrin (14.9%), chlorpyrifos 50% + cypermethrin 5% (13.9%), bromadiolone (10.7%) and aluminum phosphide (8.1%). Majority of key pesticides reported were WHO class II pesticides (45%).

The outcome of poisoning was unknown in about of the cases (44.6%). Case fatality was 5.3%. Of these deaths, there were more men (n=67, 55.4%) than women (n=54, 44.6%) and most (35.6%) were of 16-30 year age-group. Of the 121 deaths, information on the agents was not available in 57 cases (47.1%) and key pesticides was not identified in 2 cases (3.1%), where it was only classified as OP. Where found, the key pesticide responsible for the death was aluminum phosphide (n=38, 61.3%).

Forensic Science Laboratories of Nepal

Limited data were available on the identity of individual pesticides responsible for poisoning due to lack of enough national laboratory facilities as well as equipment and human resources. A total of 242 positive samples of suicidal death from pesticide poisoning data were identified from NFSL. Of these cases, 143 (59%) and 57 (23.3%) were reported as being due to ingestion of organophosphates and phosphine gas respectively. Central police forensic science laboratory (CFSL) identified 2293 positive samples of pesticide poisoning. Of them, organophosphorus (n=1283, 55.9%) was the most common pesticide followed by phosphine (n=596, 25.9%), organochlorines (n=241, 10.5%), pyrethroids (n=90, 3.9%) and carbamates (n= 83, 3.6%). Among the pesticides identified, aluminum phosphide was the most common.

The results of the study showing that aluminum phosphide and dichlorvos were the pesticides causing most deaths and poisonings in Nepal were discussed with representatives of the PQPMC and MoALD and presented to the Pesticide Registration Board. Experience from other countries showed that bans on the tablet form of aluminum phosphide pesticide has resulted in a marked reduction of fatal poisoning with this chemical.

In 2019, the Pesticide Registration Board banned eight pesticides including the high concentration (56%) 3 gm tablet form of aluminum phosphide as well as several pesticides important for suicide in South Asia (carbofuran, carbosulfan, dichlorvos, and triazophos). Import and production was banned from August 4th, 2019.

We now hope to watch the effect of these bans.

At the invitation of the Maharashtra government, CPSP is supporting the state government to collect data on pesticide poisoning deaths across the state and to use these data for pesticide policy reviews. These data will also be important for understanding the effects of India’s decision to ban 12 pesticides in 2018 with 6 more delayed to 2020. These 18 pesticides included several pesticides that have been to suicide in India. We hope that the ban will markedly reduce poisoning deaths in India.

CPSP is supporting the Centre for Sustainable Agriculture to study Andhra Pradesh’s climate resilient Zero Budget Natural Farming programme, in particular its effects on pesticide access and use, agricultural productivity, and input costs. CPSP is also analysing agricultural productivity patterns in Kerala following the state government’s ban on fourteen highly toxic pesticides in 2011, which resulted in a large reduction in pesticide suicides in the state. This was clearly shown in a paper published by CPSP earlier this year (link)

In June 2020, the Indian government proposed banning a further twenty-seven highly hazardous pesticides. Led by Indian clinicians, CPSP supported the drafting of an expert submission to support the proposal, outlining the arguments in support of the proposed pesticide ban. Most importantly, the ban includes monocrotophos, the key pesticide currently responsible for suicides in India after the ban of methyl parathion in 2018. The submission was sent to the Ministry of Agriculture & Farmers’ Welfare in July 2020.

IV. Africa

Designed by Freepik

Compared to other regions, there is limited information on the burden of pesticide poisoning and pesticide suicides on the African continent. CPSP is analysing the availability and usefulness of various data sources, while seeking to establish collaborations with researchers and organizations working on pesticide poisoning in African countries.

A scoping review is being performed for the continent to identify the surveillance systems currently in place and how they are operating. This review is being written up now for publication.

Verbal autopsy data from the Health and Demographics Surveillance Systems (HDSS) sites are a potentially important source of data for pesticide poisoning and suicides in Africa. We have established collaborations with several HDSS sites in East Africa and are looking at the strengths and weaknesses of this approach in identifying the pesticide suicides in HDSS sites. Data are being collected and analysed before publication

CPSP made contact with South Africa’s three HDSS sites in the last year and was able to collect initial data. The data are currently being analysed for publication.

Support to project in Taiwan

Suicide by pesticide poisoning is a leading method of suicide globally and in Taiwan. Banning highly hazardous pesticides (HHPs) has the potential to save hundreds of lives. This project (April 2018 – September 2020) aimed to collect and analyse data for people who attempted or died by suicide using pesticides in Taiwan to inform future global and local suicide prevention strategies. Specifically, it is aimed to

  • collect and analyse death registry and hospital record data of pesticide self‐poisoning;
  • interviews suicide attempters who ingested pesticides;
  • assess the early impact of Taiwan’s paraquat ban on pesticide suicide; and iv) raise awareness and promote policy making in support of bans on HHPs to prevent pesticide suicides by activities such as publishing opinion pieces in newspapers or online platforms or giving talks in conferences, workshops, or round tables.

Major achievements between January 2020 and August 2020, were:

  • Hospital record data were extracted for 1,633 patients who self‐poisoned using pesticides and were treated in eight study hospitals in Taiwan (2000‐2019) as of 30th June 2020. Of them, data for 154 patients were collected during the second extension period of the project (January–June 2020). However, in addition to eight study hospitals, ethical approval was obtained for two additional hospitals in East Taiwan, a mostly rural area with high suicide rates of pesticide poisoning.
  • Ten patients who self-poisoned using pesticides were interviewed within the framework of the project.
  • We assessed the early impact of the first‐stage paraquat ban (i.e. ban on import and production) by conducting preliminary data analysis of a total of 304 patients who ingested pesticides and were treated at one major regional hospital in Middle Taiwan between 2009 and 2018, including 286 patients before the first‐phase ban starting from 1st February 2018 and 18 patients after the ban. The results indicated a fall in overall fatality of pesticide self‐poisoning from 28% to 17% (p=0.42). The proportion of paraquat ingestion decreased from 29.7% to 11.1% after the paraquat ban (p=0.09), whilst that of glufosinate‐ammonium (an alternative herbicide) and organophosphates (mainly insecticides) ingestion increased from 4.5% to 22.2% (p=0.002) and from 13.6% to 33.3% (p=0.02), respectively.

Data collected in this project showed that paraquat was the leading pesticide used in both fatal and non‐fatal pesticide self‐poisonings in Taiwan. Paraquat poisoning accounted for at least 4% of total suicides in the country and as high as 14% in some rural counties. 32% of all hospital presentations of pesticide self‐poisoning and 77% of deaths in the hospital sample were due to paraquat poisoning, with a high case fatality ratio of 60%, compared to 9% for all other non‐paraquat pesticides combined. The characteristics of paraquat self‐poisonings and non‐paraquat pesticide self‐poisonings, either fatal or non‐fatal, were similar in sex and seasonal patterns, whilst those using paraquat were younger than those using other pesticides. Interviews with ten patients indicated impulsivity in the majority of the patients ‐ 50% of them spent less than 10 minutes between suicidal ideation and attempt.

The Taiwanese government banned paraquat in two stages ‐ the ban on import and production became effective from 1st February 2018 and the ban on sale and use from 1st February 2020. The ban is expected to be followed by a marked reduction in the number of deaths caused by pesticide self‐poisoning. The overall suicide rates may also decrease in some rural areas.

This pilot project demonstrated that it is feasible to collect detailed, systematic, and comprehensive information of pesticide self‐poisoning from hospital and death registry data. The project also contributed to the success of a the new research grant application.


CPSP is now starting to work with Universiti Kegangsaan Malaysia in Malaysia to use hospital-based data to study the effect of a paraquat ban on pesticide poisoning and suicides.

Pesticide poisoning is the 2nd most common method of suicide in Malaysia. A national paraquat ban was announced in 2002 but rescinded to restricted use in oil palm plantations in 2006 due to challenges in finding viable alternatives for farming industry stakeholders. Subsequently, paraquat poisoning reported to the Malaysia National Poison Centre increased 5.5 times in 2006-2015 (Leong et al, 2018). A second national ban was been implemented in Malaysia since 1 January 2020. Thus, it is crucial to establish a surveillance system that will form the basis of a reliable database of pesticide poisoning cases which can be utilised to evaluate the effectiveness of a national paraquat ban as a suicide prevention strategy in Malaysia.

This pilot project will build on 2 ethics-approved studies based on retrospective hospital-records of self-harm: (1) Bintulu Hospital’s self-harm registry (2016-2019) & (2) Ipoh Hospital’s retrospective studies of pesticide poisoning based on medical records from (2013-2019), as well as existing state forensic death registries in the catchment areas of both hospitals. Ethics approval will be obtained to extend the data collection of hospital-based records to include the time after the commencement of the national paraquat ban (1 Jan 2020-31 December 2020). Existing capacity-building efforts to improve the quality of data capture in hospital-based records of self-harm and pesticide poisoning will also be included as part of this pilot project’s hospital-based activities, i.e. continuous medical education of front-line clinicians in the departments of emergency medicine, internal medicine and psychiatry for comprehensive assessment, documentation, and management of pesticide poisoning. The pilot project will also include community-based advocacy and awareness building educational activities in collaboration with the local agricultural departments to facilitate local community dialogue and uptake of paraquat ban implementation.

International governance and human rights

Designed by natanaelginting / Freepik

International governance

The WHO Executive Board has proposed that pesticide regulation is a highly cost-effective approach to suicide prevention. The approach will be considered by the World Health Assembly later this year.

The WHO and FAO published a guideline for pesticide registrars supporting their role in suicide prevention (url)

The FAO/WHO Joint Meeting on Pesticide Management is currently developing an official policy document on pesticide regulation and suicide prevention that may be ready early in 2021.

In 2020, CPSP has engaged in discussion about the human rights impact of pesticide poisoning. It engaged with human rights experts and institutions to raise awareness of the human rights issues associated with acute pesticide poisoning.

Other issues

In September 2019, CPSP had an in-person planning meeting in Edinburgh. It was a opportunity to get together and discuss progress and challenges. During this meeting a foundation for a road map for future CPSP activities had been developed.

CPSP staff presented results of its work in at conferences in Kuala Lumpur (Malaysia), Derry/Londonderry (Northern Ireland), Edinburgh (Scotland), Kathmandu (Nepal), and other locations.

Designed by / Freepik

Plans for the future

CPSP has submitted an application to GiveWell for renewed funding.

In the new funding phase, our overall aim will be to remove highly hazardous pesticides from global agriculture. We recognise that, while the primary benefit will come from suicide prevention, it will also benefit communities affected by accidental poisoning, food and environment contamination, and destruction of biodiversity and natural enemies of pests.

CPSP aims to increase its collaborations with regional pesticide regulator groupings, and UN organisations, working to provide additional human resources for research and data analysis, and increased global capacity for HHPs ban.

In Nepal and India, CPSP’s main focus will be on seeing the effect of recent bans on suicide and other pesticide poisoning deaths and injuries.

We will increase our work outside of Nepal and India by engaging with regional pesticide regulation bodies, for example the Coordinating Group of Pesticide Control Boards of the Caribbean (CGPC).

The work will have five work streams focusing on strengthening:

  • Data Collection re Health & Agricultural Effects of Pesticides (& Bans) to Inform Regulators
  • Pesticide Regulation of HHP
  • Agronomy, Alternatives to HHP, and Communication
  • International Governance of Pesticides, particularly within the United Nations
  • Clinical Management of Poisoned Patients (link to the website).

Removing highly hazardous pesticides from agriculture requires cultural change, including movement to integrated pest management and agroecology methods which preserve natural predators while minimising pesticide use. CPSP will continue working on pesticide suicide prevention while raising awareness of other harms of HHPs.