Trends in Paraquat Poisoning in Japan — Viewed from Surveys on Clinical Cases

Objective: Paraquat poisoning occurs worldwide, and both the fatality rate and the number of deaths are out of the ordinary. Japan is one of the few countries in the world that have replaced 24% products with 5% products. This report is an attempt to introduce information about paraquat poisoning in Japan. Methods: The Japanese Association of Rural Medicine has carried out extensive surveys on clinical cases of pesticide poisoning at its 122 member installations since 2007. Of all the findings, we have picked out and evaluated those concerned with paraquat poisoning. Findings: Twenty-two out of 28 persons who attempted to commit suicide with paraquat died in 2007–2011. The rate of deaths from suicide attempts with paraquat stands at somewhere near 80% or so even with 5% products, so it appears that the attempts to reduce the death rate did not have the intended effect even with products having a lower concentration. Conclusion: The “outcome prediction line” propounded in 1979 still stands today, while a wide variety of therapies have been studied. It seems that paraquat should at least be classified into Class Ib (highly hazardous) given that the mortality remains high and efficacious therapies remain elusive.