Paraquat poisoning, what we should know

Abstract

Paraquat (PQ) a brown syrupy liquid also known as methyl viologen is a commonly used herbicide in India. A highly toxic compound to humans, although, a large majority of fatalities from PQ poisoning are suicides. Accidental exposure is causing immense harm to farmers and agriculture workers, which is not documented. Accidental or deliberate ingestion has an extremely high case-fatality rate, and clinical features are due to generating reactive oxygen species which cause cellular damage ultimately leading to multiorgan failure. At present there is no antidote to PQ poisoning, various treatment modalities from immunosuppressants to antioxidants are used with no clear clinical efficacy. Elimination methods such as haemodialysis and haemoperfusion when done early have shown to be useful in few studies. Recently drug-like Edaravone and Perfenidone are being used but with no survival benefit. Neither proper information nor training on the use of PQ and personal protective equipment are provided by agriculture offices to farmers leading to accidental exposure. Hence paraquat use has been restricted in many parts of the world and an appeal for a ban in India is underway as a need for preventive measures.