The burden of suicide by paraquat poisoning in Taiwan (1987–2017): trends, geographic variations, and demographic characteristics

Abstract

Pesticide self-poisoning accounts for 14%–20% of global suicides. Paraquat, a highly lethal pesticide, is involved in a considerable number of suicides in some countries. This study investigated the burden, trends, geographic variations, and demographic characteristics of pesticide and paraquat suicides in Taiwan. Suicide data (1987, 1992, 1997, and 2002–2017) were obtained from Taiwan’s cause-of-death mortality data files. Trends and geographic variations in pesticide and paraquat suicides were examined using graphs and maps. Logistic regression was used to investigate the differences in the characteristics of pesticide versus non-pesticide suicides and paraquat versus non-paraquat pesticide suicides. Age-standardised pesticide suicide rates decreased by 74%, from 7.7 to 2.0 per 100,000, in 1987–2017. Paraquat was the leading agent involved in pesticide suicides, accounting for 59.9% (2,268/3,786) of pesticide suicides where the pesticide agents involved were recorded on the death certificate and at least 4.0% (2,268/56,361) of overall suicides in Taiwan. The percentage of paraquat suicides in overall suicides varied markedly across cities/counties (0.4%–15.6%). Pesticide suicides were more likely to be male, older people aged 65 + years, and from rural areas than non-pesticide suicides. By contrast, paraquat suicides tended to be younger than non-paraquat pesticide suicides, with no difference in sex distributions in the two groups. The ban on paraquat implemented in 2018–2020 would have a significant impact on pesticide suicides and overall suicides, particularly in high-risk areas and demographic groups.