A thermodynamic insight into the detoxification of mercury(II) by thiosulfate as a potentially superior antidote to manage mercury poisoning

Abstract

The need to manage mercury poisoning is so urgent that it is, in the words of some authors, the ‘need of the hour.’ Many organic compounds have been tested as antidotes for mercury(II) poisoning, and all of them supposedly encourage the metal to move from sulfhydryl-containing proteins to them as therapeutic chelating agents. In light of a certain Ryskulov’ observations in 1988, this article reported a thermodynamic insight into the detoxification of mercury(II) by thiosulfate as a superiorly alternative antidote. The pathway that sulfur, starting as aqueous thiosulfate ions, undergoes to detoxify aqueous mercury(II) ions was thermodynamically studied through examining numerous equilibrium constants (some calculated from electrochemical data), and the extent of mercury conversion into metacinnabar, somehow representing the effectiveness of thiosulfate as a mercury(II) antidote, was thermodynamically quantified through calculating the net equilibrium constant. It was concluded that in the mercury(II)-thiosulfate chemical equilibria, almost all of the mercury(II) that is not in any mercury(II)-thiosulfate complex form is in the form of the unreactive precipitate metacinnabar. That suggested antidotal effectiveness and justified the need to continue in vivo studies on thiosulfate as a potentially superior mercury(II) antidote.