Engineered nanoparticles are increasingly produced because of their innovative functionalities and are used in consumer products (such as personal and home care products, clothes, paints, and toys) and different processes (e.g., biomedical, electronic, industrial, and environmental). Their unique size‐dependent physicochemical properties are often the reason for their use; however, these same properties have prompted their environmental concern. Difference in their physicochemical properties compared to conventional anthropogenic stressors like chemicals, may imply that the way uncertainty is addressed in conventional risk assessment methods is not fit to evaluate engineered nanoparticles. In recent years, there has been much work done on the exposure and effects of engineered nanoparticles in the environment with few papers trying to characterise risk. Jacobs et al. 1 describes a thoroughly conducted and innovative study on a probabilistic environmental risk assessment of TiO2 nanoparticles. The authors present a novel method to model variability and uncertainty separately in the environmental risk assessment of engineered nanoparticles, so their separate contribution can be assessed. By doing so the authors provide clear guidance for future research in order to reduce uncertainty in the risk assessment of engineered nanoparticles, something that is greatly needed for their sustainable use.