Identification of an Unknown Poison in Pharmaceutical Formulations – A Forensic Study of Culpable Homicide Case

Homicide, the intentional killing of one person by another occur for a variety of reasons, might be because of personalconflicts, domestic violence, revenge, financial gain, gang-related disputes. Most commonly encountered ways are usingone’s body parts as weapon, firearms in gun-prevalent societies, sharp objects like knives or machetes, blunt force traumausing bats or hammers, strangulation, poisoning, drowning, vehicular homicide, arson, and even explosives in cases oftargeted killings or terrorism. Mixing of poison in food or water is an age old technique followed from ancient times to killenemies for acquiring kingdom or personal gains. In recent times, mixing of poison in medicines is also practiced to commithomicide. A case was registered in Srikakulam District of Andhra Pradesh State, where the perpetrator followed the sametechnique by mixing unknown poison in pharmaceutical formulations (syrup and eye drops) in disguise of free distributionof covid medicines. A high performance thin layer chromatography (HPTLC) and UV-Visible spectrophotometer (UV-Vis)was used for the separation and identification of poison present in the pharmaceutical formulations seized in the crimescene. It was confirmed that Paraquat a herbicide poison was found in the seized material objects. The described HPTLCmethod can be used routinely in the forensic science laboratories for identification of Paraquat not only in pharmaceuticalformulations but also in the viscera samples.