Evaluation of potential engineered nanomaterials impacts on human health: from risk for workers to impact on consumers

A growing number of engineered nanomaterials (ENMs) are produced and marketed. Increasing human exposure is, therefore, expected in the next years and, in parallel, increased concerns on potential health impact will be raised with particular reference to workers engaged in ENM production, handling, or disposal. Moreover, ENMs are also present in products widely present on the market, such as food additives or cosmetics, so that potential effects on human health could involve a larger population. However, until now, no adverse health effect in humans has been clearly demonstrated to be ENM-specific. Although the huge amount of data on ENM biological effects, obtained using in vitro models and experimental animals, cannot be used to demonstrate ENM-related adverse outcomes in humans, they have produced valuable information on the complex and dynamic interactions between ENM and living systems. At the light of these developments, lack of documented health effects should not be taken as an absolute evidence of absence of ENM-related risks, but, rather, as a powerful drive to increase research efforts toward a robust preventive evaluation of ENM potential toxicity before their entry the market.