Multiple roles of dissolved organic matter on typical engineered nanomaterials: environmental behaviors, pollutants removal and potential risks

With the rapid development of nanotechnology, engineered nanomaterials (ENMs) have been produced and widely used in various fields, especially in environmental protection. ENMs would be released into the environmental media, particularly natural water, and then they exert great risks to ecosystem safety and human health. Dissolved organic matter (DOM) commonly exists in water environments. As a result, the interactions between DOM and ENMs are bound to occur. Herein, the multiple roles of DOM on ENMs are summarized. DOM can often interact with ENMs to positively or negatively influence nanomaterials-mediated pollutant removal through adsorption and catalytic degradation processes. On the other hand, DOM also regulates the potential ecotoxic effects of ENMs on organisms, either mitigation or enhancement. ENMs in turn would alter the physicochemical properties of DOM along with their environmental behaviors and risks. The present review aims to provide insight into DOM's influence on environmental behaviors, environmental applications, and potential risks of ENMs. Graphical Abstract