It is shown that among the dust produced from plasma–surface interaction in tokamaks, nanoparticles growing in gas phase can be produced in large quantities in MAST and Tore Supra, two tokamaks of carbon-based plasma-facing components. Laboratory plasma experiments and models are also presented showing that when carbonaceous species are present, complex chemical pathways which depend strongly on plasma conditions lead to various molecular precursors. Despite this fact, the final solid particles produced in the laboratory plasmas and tokamaks considered here, present similarities giving information on their growth and transport in the plasma.