A Forensic Case of Suicide Ingestion of Paraquat Herbicide: New Histological Insights and Revision of the Literature.

Abstract: Paraquat (PQ) is one of the most widely used herbicides in the world, and poisoning is generally associated with accidental, suicidal, or homicidal events. Therefore, in the forensic context, PQ could be in various ways involved as a possible cause of death of a subject. However, even though its systemic toxicity is known, the biological effects exerted on individual viscera have been explored only to some extent, especially in case of victim's survival. Therefore, a case concerning a suicidal ingestion of PQ with survival of 3 days was deemed of interest. Clinical toxicological analyses confirmed acute PQ intoxication, and after the death of the victim, an autopsy was performed showing local and systemic signs of ingestion of a caustic substance. Histologic examination revealed marked cellular damage to the major viscera, particularly the gastroesophageal tract, liver, kidneys, and lungs, with initial alveolar fibrosis noted despite the patient's short survival. This finding represents a new element in the context of PQ lung injury, as it has not been previously documented in the literature. Thus, histological findings in lethal intoxications after survival can reveal specific peculiarities still unknown and, therefore, assume transversal relevance not only at forensic but also clinical level.