Systems Toxicological Approach to the Risk Assessment of Nanomaterials

Nowadays, nanomaterials have come into the spotlight as new materials that have lots of prominent benefits in various fields of human life. Risk assessment of the nanomaterials requires a multidisciplinary understanding of the differences from their large particles in surface physicochemistry and dosimetry. The size, biological effective dose, surface chemistry, interactions with biological membrane and dispersion media are important factors that make unique characteristics of nanomaterials in their toxicity potency. Conventional methods for the toxicological assessment may have limitations in proper understanding of the dose-response relationships of the diversity of structures and compositions of nanomaterials. Challenges to toxicological testing of nanomaterials will be covered with the strategy of systems toxicology including toxico-genomics, toxico-proteomics and toxico-metabolomics. The data driven from systems toxicology are valuable in the identification and characterization of the mode of action of nanomaterials. Many of toxicogenomic and toxicoproteomic studies have released that the production of reactive oxygen species and inflammation caused by oxidative stress are the key mechanism of toxicity of nanomaterials. However, there is still limited information for the assessment of toxicity thresholds based on dose-response relationships and for the estimation of exposure in risk assessment of nanomaterials. More integrated and systemic studies are required for the risk assessment of human health impact considering various but unique properties of nanomaterials. Keywords: nanomaterials; systems toxicology; toxico-genomics; toxico-proteomics; toxico-metabolomics; risk assessment