The UK government’s workplace health and safety watchdog has called for “a precautionary approach” to the use of carbon nanotubes (CNTs). The Health and Safety Executive (HSE) information sheet says: “If their use cannot be avoided, HSE expects a high-level of control to be used,” adding: “It is good practice to label the material ‘Caution: substance not yet fully tested’.”

Risk management of carbon nanotubes, HSE information sheet, March 2009 [pdf]. Risks 397.