Occurrence of the agricultural nitrification inhibitor, dicyandiamide, in surface waters and its effects on nitrogen dynamics in an experimental aquatic system

► This study focuses on downstream impacts of an agricultural nitrification inhibitor. ► DCD was measured in surface waters in an agricultural area. ► Its concentration in surface waters was correlated with environmental variables. ► DCD inhibited nitrification in wetland sediment-water mesocosms. ► At typical concentrations, DCD perturbed N-cycling in an aquatic system.