Pesticide surveillance and deaths by suicide
Rakhi Dandona & David Gunnell
The Lancet | Open Access | Published: April 23, 2021 | DOI:https://doi.org/10.1016/S2214-109X(21)00174-1
Highly hazardous pesticides are among the leading causes of death by suicide in low-income and middle-income countries. National bans on these products have led to substantial reductions in pesticide-attributable deaths in many countries and, in some nations, falls in overall suicide mortality.
First, Buckley and colleagues highlight the high case fatality (7·2–8·6%) in episodes of poisoning with five commonly ingested pesticides, which together account for nearly a quarter of pesticide deaths in Sri Lanka since 2013. Notably, these five pesticides are class II products according to WHO’s hazardous pesticide classification, which is based primarily on acute oral and dermal toxicity in rats.
Second, the marked reduction in suicide deaths from pesticide poisoning in Sri Lanka shows the potential of a data-driven approach based on good quality surveillance. The pesticides that were banned in Sri Lanka included those that contributed the most to poisoning deaths at any particular time, in addition to those categorised as most hazardous by WHO.
Third, the fall in case fatality over time for poisonings due to several specific pesticides in Sri Lanka highlights the potential impact of improved medical management of poisoning on mortality. Buckley and colleagues note the availability of more emergency departments, postgraduate training in toxicology, updated treatment guidelines, and wider availability of antidotes in Sri Lanka over the study period.
Lastly, credible evidence now exists from many countries that national bans on hazardous pesticides have resulted in fewer suicide deaths without affecting agricultural yield. Previously favoured policies of advising farmers to store their pesticides securely have not been shown to be effective.
DG was an expert adviser to WHO’s Consultation on cost-effectiveness of suicide prevention interventions, including pesticide regulation (2019). He provided technical assistance for the development and publication of a WHO resource tool for suicide prevention: a resource guide for pesticide registrars and regulators (2019). He was a member of the scientific advisory group for a Syngenta-funded study to assess the toxicity of a new paraquat formulation (2002–06); a member of the scientific advisory group for a pesticide storage project funded by Syngenta (2005–07); and chaired the data monitoring and ethics committee for a Syngenta-funded trial of the medical management of paraquat poisoning (2007–10); he received travel costs to attend research meetings but no other fees. DG was also an expert adviser to WHO’s First Consultation on Best Practices on Community Action for safer access to pesticides (2006). RD declares no competing interests.
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Published: April 23, 2021
© 2021 The Author(s). Published by Elsevier Ltd.