The research on carbon-based nanomaterial (C-NM) composites has increased in the last two decades. This family of functional materials shows outstanding mechanical, thermal and electrical properties, and are being used in a variety of applications. An important challenge remains before C-NM can be fully integrated in our production industries and our lives: to assess the release of debris during production, use, and misuse of composites and the effect they may have on the environment and on human health. During their lifecycle, composites materials can be subjected to a variety of stresses which may release particles from the macroscopic range to the nanoscale. In this review, the release of debris due to abrasion, weathering and combustion as well as their toxicity is evaluated for the three most used C-NM: Carbon Black, Carbon Nanotubes and Graphene-related materials. The goal is to stimulate a Safe-By-Design approach by guiding the selection of carbon nano-fillers for specific applications based of safety and performance.