The contemporary ‘risk society’ is associated with the emergence of a wide range of risks characterised by uncertainty and unfamiliarity. These ‘novel’ risks pose a major challenge for organizations: their negative effects may be significant, but prevailing risk assessment techniques are limited in their ability to identify them. Building on our prior work on the chemical bisphenol A (BPA), this study examines how organizations deal with novel risks. It finds that organizations engage in ‘risk translation’ by translating equivocality associated with the novel risk into more familiar risks, which provide them with a clearer basis and guide for action. As organizations take actions to manage these translated risks, an ‘ecology of risks’ evolves which, over time, allows for the construction of a novel risk. The study contributes to research on organizing and risk by theorizing how organizations respond to novel risks, as well as by highlighting the role of translated organizational risks in constructing novel risks and shaping societal responses to grand challenges.