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Nowadays, nanotechnology is applied to an increasingly number of industries due to the unique properties of nanomaterials. Carbon nanotubes and carbon nanofibers are some of the most appealing nanomaterials that are commonly employed in electronics, photovoltaic, catalysis, environmental engineering, space engineering, and last but not least in medicine and pharmacy. However, the issue of handling such materials is not yet fully investigated. Without the essential and proper legislations and regulations, widespread use of nanotechnologies in many sectors of society may well be slowed down and could even come to a complete standstill. Thus, it is necessary to develop innovative methods for risk management. The exposure assessment of carbon based nanomaterials presents several challenges. It is easily understood that nanosafety and risk assessment are upon modern research fields. Moreover, it seems critically important to take into perspective the whole life cycle for carbon nanotubes and carbon nanofibers for the risk management. The purpose of this review is to present the current state of knowledge related to the risks of carbon nanotubes and nanofibers as well as to display the current actions in European Union regarding this issue.

Purpose – The purpose of this paper is to produce cobalt (Co)-based thin films by metalorganic chemical vapor deposition (CVD) technique and then to evaluate structural and mechanical integrity. Design/methodology/approach – Co-based thin films were produced by metalorganic CVD technique. Boronizing, carburization and nitridation of the produced Co thin films were accomplished through a post-treatment stage of thermal diffusion into as-deposited Co thin films, in order to produce cobalt boride (Co2B), cobalt carbide and cobalt nitride thin films in the surface layer of Co. The surface topography and the crystal structure of the produced thin films were evaluated through scanning electron microscopy and X-ray diffraction, respectively. The mechanical integrity of the produced thin films was evaluated through nanoindentation technique. Findings – The obtained results indicate that Co2B thin film exhibits the highest nanomechanical properties (i.e. H and E), while Co thin film has enhanced plasticity. The cobalt oxide thin film exhibits higher resistance to wear in comparison to the cobalt thin film, a fact that is confirmed by the nanoscratch analysis showing lower coefficient of friction for the oxide. Originality/value – This work is original.