Longer-term impact of pesticide bans on suicide in South Korea

Introduction:
Pesticide self-poisoning accounts for 14%–20% of global suicides. South Korea banned paraquat and eight insecticides commonly involved in suicide in 2011–2012. We investigated the longer-term (2013–2019) impact of the pesticide bans on reducing suicides in South Korea.

Methods:
Suicide data by sex, age, area and method among people aged 15 years or above were extracted from registered death data (1997–2019). Data for suicide by self-poisoning using different categories of pesticides (herbicides and fungicides; insecticides; rodenticides and other pesticides; and unspecified pesticides) were also extracted. Segmented regression analyses were used to estimate step (level) changes in pesticide suicide rate in 2012 (ie, the intervention period) and 2013–2019 (ie, the post-intervention period) as well as the slope (trend) changes in pesticide suicide trends in 2013–2019 (vs the 2003–2011 pre-intervention period).

Results:
The bans on paraquat and eight insecticides (2011–2012) were followed by a 15% reduction in pesticide suicide rates in 2012 and a further 36% reduction in 2013, accompanied by an additional 6% annual decline in trend in 2013–2019 versus 2003–2011, with an estimated 8353 pesticide suicides averted (2012–2019). The reduction was mainly found in males, older people aged 70+ and rural populations. The greatest impact was found in suicides involving herbicides and fungicides (including paraquat) and insecticides across the categories of pesticides. No evidence was found for a shift to other poisoning suicides or an impact on agricultural yields of the pesticide bans.

Conclusion:
South Korea’s pesticide bans in 2011–2012 were followed by a sustained decrease in pesticide suicides in the 7-year period (2013–2019) after their implementation. National policies restricting or banning highly hazardous pesticides commonly involved in self-poisoning can prevent many suicide deaths over a sustained period. Additional regulatory efforts could further reduce these unnecessary premature deaths.