Graphene, the new allotrope of carbon is a single layer of monocrystalline graphite with sp2 hybridized carbon atoms. This compound has received worldwide attention due to its extraordinary physical and chemical properties. Duo to the widespread application of geraphenes, concerns are raising about its environmental safety or the safety protocols for handling and waste of graphene-based materials. The generation of reactive free radicals, adsorption of important biomolecules, and physical toxicity of graphene also matter. Hereby we criticize the concerns on the toxicity of graphenes to provide some perspective on the potential hazards of future development in graphene-based biomaterials.