Modelling the occurrence and reactivity of the carbonate radical in surface freshwater

A model was developed to foresee the degradation kinetics of dissolved compounds for reaction with the carbonate radical in surface waters. It would contribute to the assessment of the environmental persistence of pollutants, therefore, allowing a better definition of the exposure of natural ecosystems and human communities to hazardous substances. The model is a function of the water chemical composition, the water column depth, and the second-order rate constant of the reaction between the relevant compound and the carbonate radical. A comparison between the reactivity of the carbonate and the hydroxyl radical shows that the latter would often play a more important role as reactive species, but the carbonate radical could prevail in carbonate-rich waters, giving the degradation of easily oxidisable molecules.