Triple Homicide With Thallium Sulfate: Microscopic Postmortem Findings at Different Survival Time

Thallium was widely used as a rat poison, but because of its high toxicity, it was banned from the market. Due to these limitations, its use for homicidal purposes has become a rare event over the years, and the biological signs of this fatal poisoning remain unclear and elusive, similar to the histologic lesions it induces. For this reason, we valuated it appropriate to report a specific and targeted focus on the microscopic pictures of this poisoning, given the uniqueness of the forensic case brought to our attention. In fact, not only were they 3 subjects who died of homicidal thallium poisoning, but also with different survivals, which made it possible to investigate the short and medium-term effects, currently completely unknown in the literature. In particular, both the signs related to the gastrointestinal transit of the toxic substance and the systemic ones due to its metabolization were documented, focusing mainly on viscera with high functional dignity and fully justifying the death of the victims. We therefore present the microscopic evidence that has emerged and discuss its forensic relevance, associating a complete and broad iconography, with the aim of enriching knowledge on this specific topic that is still little explored.