2,4-dinitrophenol intoxication and its morphological findings as an indication of substance intake

Lethal intoxications can only very rarely be recognized during an external examination of corpses, as poisoning does not leave any characteristic findings on the deceased. The present study is a retrospective review on 2,4-dinitrophenol (2,4-DNP) intoxications in human subjects from the beginning of the 20th century until today, as well as a case report on a fatal intoxication of a 50-year old obese man in Rostock (Germany) and an introduction for toxicological analysis in post-mortem specimens of the substance ingested in these rare cases. Via selective literature search, the information on occurrence and localization of abnormal pathomorphological external and/or internal findings in cases of 2,4-DNP ingestion/ intoxication was gathered. By 2021, a total of 13 case reports with information on morphological findings due to 2,4-DNP ingestion/intoxication were found. The external findings were dominated by yellowing of the skin, followed by exanthemas/rashes and yellowing of the sclera. The internal findings included yellowing of the internal organs, yellow color of the stomach contents, yellowing of the mucous membranes and an intense yellow color of the urine. Yellowish discoloration of the skin, sclera, mucous membranes, internal organs, sweat and/or an intensive yellow discoloration of the urine are not observed in every 2,4-DNP intoxication. However, when they do occur, they are a characteristic indication of 2,4-DNP ingestion and, if localized to the skin, indicate prolonged consumption. A fatal case from Rostock in 2016 due to prolonged intake of 2,4-DNP for weight loss is exemplified. A simple, fast and cost-effective workup combined with HPLC-DAD for post-mortem toxicology ultimately delivers reliable analysis results.