The chemical element identified as K was present in the blood work of the Trandoshan individual Nack Movers. This analysis was performed by Russo-ISC, a crime scene analysis droid belonging to the Coruscant Security Force, following Movers' murder via sennari poison in 7958 C.R.C.. The blood sample revealed a 5.2 concentration of K, though the droid did not classify it as a pollutant.
Pablo Hidalgo's 2018 sourcebook, Star Wars: Scum and Villainy: Case Files on the Galaxy's Most Notorious, initially brought K to light.