Engineered nanoparticles at the workplace: current knowledge about workers ’  risk

Background The novel physicochemical properties of engineered nanoparticles (ENPs) make them very attrac-tive for industrial and biomedical purposes, but concerns have been raised regarding unpredictable adverse health effects in humans. Current evidence for the risk posed by ENPs to exposed workers is the subject of this review. Aims To perform an in-depth review of the state of art of nanoparticle exposure at work. Methods Original articles and reviews in Pubmed and in principal databases of medical literature up to 2013 were included in the analysis. In addition, grey literature released by qualified regulatory agencies and by governmental and non-governmental organizations was also taken into consideration. Results There are significant knowledge and technical gaps to be filled for a reliable evaluation of the risk posed for workers by ENPs. Evidence for potential workplace release of ENPs however seems sub-stantial, and the amount of exposure may exceed the proposed occupational exposure limits (OELs). The rational use of conventional engineering measures and of protective personal equipment seems to mitigate the risk. Conclusions A precautionary approach is recommended for workplace exposure to ENPs, until health-based OELs are developed and released by official regulatory agencies. Key words Engineered nanoparticles; health effects; metrics; occupational exposure limit; workplace exposure