MADALINA DIAC, ANTON KNIELING, SIMONA IRINA DAMIAN, DIANA BULGARU ILIESCU, ION SANDU, CRISTINA FURNICA, CATALIN JAN IOV, SOFIA DAVID FORENSIC ASPECTS IN POLONIUM-210 POISONING The human body is exposed to radiation resulting from the presence and degradation in the environment of natural radionuclides like uranium and thorium. In laboratories, several radioactive isotopes are being used: uranium-235, iodine-131, cobalt-60, and carbon-14. These radioactive isotopes are useful in scientific (dating human skeletal remains) and medical purposes (radiotherapy/radiodiagnosis), but they are also used in criminal context. Polonium 210 (Po-210) is a natural radioisotope occurring in the natural environment as consequence of uraniu-238 decay chain. The current paper presents a less known subject of lethal poisoning with Po-210 radioisotope, in order to underline the methods used for Po-210 identification in forensic samples. The authors performed a literature review of the scientific researchers published in the last years concerning polonium sources and its use as a poison. Polonium’s effectiveness as a poison relies on its chemical characteristics only to the extent that they determine the isotope’s distribution and retention in organs and tissues; the alpha particles are responsible for the lethal effect. Po-210 poisoning is particular, as it doesn’t leave traces, it can be easily transported, and is not detected by airport scanners. Identifying this compound during a medico-legal autopsy is very difficult, as the post-mortem examination will not yield characteristic aspects, the forensic pathologist being forced to consider this as a potential cause of a rapid death, with significant visceral damage.