Published: December 2017

Note: This page summarizes the rationale behind a GiveWell Incubation Grant to the Centre for Pesticide Suicide Prevention (CPSP). CPSP staff reviewed this page prior to publication.

Summary As part of GiveWell’s work to support the creation of future top charities, in August of 2017, the Centre for Pesticide Suicide Prevention (CPSP) received a GiveWell Incubation Grant of $1,336,409 to start work aimed at reducing deaths from deliberate ingestion of pesticides. The organization plans to use these funds to start collecting data on pesticide suicides in Nepal and India with the aim of assisting governments in enacting bans on the most lethal pesticides currently used in suicide attempts. We see the main rationale for this grant as the possibility of a large and sustained reduction in suicide rates.

We have had the following conversations about updates on this grant:

The problem

The World Health Organization (WHO) estimates that 800,000 people die due to suicide each year. The most recent comprehensive systematic review we identified in our research suggests that ~14%-20% of global suicides between 2010 and 2014 were due to deliberate ingestion of pesticides, although we have not investigated the individual studies in this review. A WHO report claims that pesticide suicide is particularly prevalent in rural populations, where agricultural workers have easy access to pesticides.

The intervention

CPSP plans to collect data in India and Nepal on which pesticides are most commonly used in suicide attempts, and are most likely to result in death. CPSP plans to use this data to help the governments of India and Nepal decide which pesticides to ban, with the intention of reducing suicide rates.

Evidence of effectiveness

The strongest evidence we have found that pesticide bans reduce suicides is from two observational time series analyses in Sri Lanka, described in more detail below. We do not think the evidence is conclusive (it is probable that other factors partially contributed to the decline in suicides), but believe it is more likely than not that the decline in suicide rates in Sri Lanka was primarily caused by the pesticide bans, as the banned pesticides were commonly used in self-harm and had a high case fatality relative to other methods of self-poisoning.

Evidence from Sri Lanka

We found two observational time series analyses in Sri Lanka, which find a substantial decline in suicide rates following pesticide bans aimed at reducing suicides.

Gunnell et al. 2007 finds a 50% decline in the suicide rate between 1995 and 2005. The decline followed bans on pesticides commonly used in suicide (methamidophos and monocrotophos in 1995, endosulfan in 1998) and appears to be driven by a decline in suicide by self-poisoning.

Knipe et al. 2017 finds a 21% decline in the suicide rate between 2011 and 2015. The decline followed phased bans of pesticides commonly used in suicide (paraquat, dimethoate, fenthion) between 2008 and 2011 and appears to be driven by a decline in suicide by self-poisoning.

We note two major limitations of these studies, which limit causal inference:

They use time series data, with no comparison group. It is possible that the decline in pesticide suicides was caused by events other than the pesticide ban.

They use national level suicide data of uncertain quality.

However, we find the case that the decline in suicides was primarily caused by the pesticide bans reasonably compelling. Two analyses of Sri Lankan hospital records for poisoning patients indicate that (i) the banned pesticides were among the most commonly used in suicide and (ii) self-poisoning with the banned pesticides was more likely to result in death than self-poisoning with other pesticides.

The organization

Track record

CPSP is a new organization, started by Michael Eddleston, a professor of Clinical Toxicology at the University of Edinburgh whose research focus is self-harm through poisoning. Professor Eddleston spent four years in Sri Lanka as a Wellcome Trust Fellow in the 2000s researching pesticide suicide. The Sri Lankan pesticide registrar at the time has said that Professor Eddleston's work was important for deciding which pesticides to ban. We discuss the evidence that pesticide bans in Sri Lanka caused a reduction in suicide rates above.

Activities

CPSP expects to conduct activities to meet the following milestones:

December 1, 2017 : Completed recruitment of in-country staff and established an office alongside the pesticide registrar in Nepal and India. Identified 5-10 sentinel hospitals in Nepal and 20-30 sentinel hospitals in India from which to collect medical records, including (i) number of pesticide suicides (ii) which pesticides are most commonly used in suicide attempts (iii) case fatality from self-poisoning with different types of pesticide. Signed Memorandum of Understanding for joint working with the Food and Agriculture Organization of the United Nations (FAO), which also works on pesticide regulation.

: April 1, 2018 : Completed training of data collection staff to collect medical records. Begin collection of medical records from sentinel hospitals.

: September 1, 2018 : Completed collection of first six months of medical records and started analysis to determine which pesticides are commonly used in attempted suicide and have high case fatality. Start discussing which pesticides should be banned with pesticide registrars and FAO.

: December 1, 2018 : Completed analysis of medical records and decided which pesticides to recommend for regulation. Begin drafting legislation to ban selected pesticides.

: March 1, 2019 : Legislation to ban selected pesticides implemented.

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After legislation passes, CPSP would train government staff to monitor the effectiveness of pesticide bans on reducing suicide rates. CPSP may also raise additional external funding to run a cluster randomized controlled trial in India on the effect of reducing availability of particular pesticides on suicide rates.



Budget

CPSP plans to use this grant to cover the below program costs for two years:

Core international staff and administration: $459,317

Program in India: $270,000

Program in Nepal: $138,000

International travel: $146,000

Consultants: $145,600

Training: $56,000

An additional $121,492 (equal to 10% of the above program costs) will cover costs to the University of Edinburgh, in which CPSP will be housed.



Cost-effectiveness

We constructed a cost-effectiveness model for CPSP’s activities. We roughly estimate that, in expectation, CPSP’s activities will be ~9x as cost-effective as cash transfers to people living in extreme poverty. This estimate depends on inputs for a number of parameters which are particularly subjective or difficult to estimate.

The inputs into this cost-effectiveness analysis which we are most uncertain about are:

The probability that pesticide bans are implemented as a result of CPSP’s work in India and Nepal.

Government costs of implementing pesticide bans.

The discount we apply to the costs incurred by governments to implement a pesticide ban.

The value of preventing a suicide through means restriction, relative to preventing a child's death from malaria.

Room for more funding

The grant is intended to fully cover operational costs for two years, and is the first significant funding CPSP has received.

Professor Eddleston told us that he has previously found it difficult to raise funds for CPSP, so we think it likely would not have attracted funding from elsewhere without this grant.

Risks of the grant

We see a number of potential risks to the success of this grant:

Strength of evidence. The case for pesticide bans reducing suicides relies on a limited number of observational studies. It is possible that the reduction in suicide in Sri Lanka was, at least partially, caused by factors other than pesticide bans, and/or that pesticide bans in India and Nepal would not result in similarly large declines in suicides.

The case for pesticide bans reducing suicides relies on a limited number of observational studies. It is possible that the reduction in suicide in Sri Lanka was, at least partially, caused by factors other than pesticide bans, and/or that pesticide bans in India and Nepal would not result in similarly large declines in suicides. Agricultural production. Banning commonly used pesticides may have a negative impact on agricultural yields, or increase input costs for farmers. A time-series analysis of crop yields in Sri Lanka found no noticeable reduction in net agricultural production in Sri Lanka following pesticide bans and we have not seen evidence that banning 79 different pesticides in Mozambique (for reasons unrelated to suicide) caused a decline in agricultural production. However, we believe it is unlikely that small decreases in net agricultural production would have been detected.

Banning commonly used pesticides may have a negative impact on agricultural yields, or increase input costs for farmers. A time-series analysis of crop yields in Sri Lanka found no noticeable reduction in net agricultural production in Sri Lanka following pesticide bans and we have not seen evidence that banning 79 different pesticides in Mozambique (for reasons unrelated to suicide) caused a decline in agricultural production. However, we believe it is unlikely that small decreases in net agricultural production would have been detected. Influencing policy. The success of CPSP's work will depend on the engagement of policymakers, which is difficult to predict. We have seen an email from the Ministry of Agriculture in Nepal asking for CPSP’s assistance, but remain uncertain whether CPSP will be able to translate its research into policy change.

The success of CPSP's work will depend on the engagement of policymakers, which is difficult to predict. We have seen an email from the Ministry of Agriculture in Nepal asking for CPSP’s assistance, but remain uncertain whether CPSP will be able to translate its research into policy change. New organization. As CPSP is a new organization, we have not yet seen evidence that it will be able to effectively implement the activities described above.

Plan for follow up

We expect to have conversations with CPSP every few months to check in on progress, with a major check-in 12 months after the initial grant is received.

Internal forecasts

For this grant, we are recording the following forecasts:

Confidence Prediction By Time Elie: 67%; James: 65% We recommend a second grant to CPSP July 1, 2019 Elie: 33%; James: 55% Conditional on CPSP entering Nepal, Nepal will pass legislation to ban at least one of the three pesticides most commonly used in suicide. July 1, 2020 Elie: 5%; James: 10% Conditional on CPSP entering India, India will pass legislation to ban at least one of the three pesticides most commonly used in suicide. July 1, 2020 Elie: 15%; James: 35% Conditional on CPSP entering India, a state in India will pass legislation to ban at least one of the three pesticides most commonly used in suicide. July 1, 2020 James: 85% for each Conditional on legislation to ban pesticides used in suicide being passed in Nepal / India, the pesticide suicide rate is lower in the combined three years after the ban than it is in the three years before the ban (as determined by national level data or representative survey data) 3 years after legislation passed James: 40% for each Conditional on legislation to ban pesticides used in suicide being passed in Nepal / India, the pesticide suicide rate is >10% lower in the combined three years after the ban than it is in the three years before the ban (as determined by national level data or representative survey data) 3 years after legislation passed James: 20% for each Conditional on legislation to ban pesticides used in suicide being passed in Nepal / India, the pesticide suicide rate is >15% lower in the combined three years after the ban than it is in the three years before the ban (as determined by national level data or representative survey data) 3 years after legislation passed

Our process

Professor Eddleston contacted one of our researchers (James Snowden) about funding in 2016, when James was working at the Centre for Effective Altruism. We continued to investigate the grant when James started working for GiveWell in March 2017. We had two additional conversations with Professor Eddleston and Dr. Leah Utyasheva (CPSP’s Policy Director) before deciding to make this grant. We also spent significant time constructing a cost-effectiveness model, and reviewing the evidence that pesticide bans caused a decline in suicide rates in Sri Lanka.

Sources