Applicable risk assessment methods in occupational and environmental exposure to nanoparticles - a narrative review

Nanoparticles (NPs) are a heterogeneous group of materials that have various applications, and their risk assessment is an essential condition. This study aimed to review the applicable risk assessment methods in occupational and environmental exposures to NPs. A literature search for articles published since 2005 in Web of Knowledge, Scopus, PubMed, Science Direct, and Google Scholar, using appropriate keywords such as “Risk Assessment,” “Nanoparticle,” and “Nanomaterial,” revealed 56 articles, which were screened by two researchers. A total of 15 articles were reviewed in full text. In total, 11 applied techniques for NP risk assessment were analyzed. Seven methods were quantitative, and four were qualitative. The quantitative methods were Integrated Probabilistic Risk Assessment (IPRA), Integrated Probabilistic Environmental Risk Assessment (IPERA), Quantitative Structure-Activity QSTR-Perturbation Model, Lung Dosimetry Modeling for Quantitative Risk Assessment (LDMQRA), Physiologically Based Pharmacokinetic Modeling (PBPK), Risk assessment based on toxicokinetic modeling, and Risk assessment of NPs with Spray Application. The qualitative methods were Application of Toxicogenomics for Risk Assessment, Luminous Microbial Array for Toxicity Risk Assessment (Lumi MARA), Control Banding Nano Tool (CBNT), and Stoffenmanager Nano Tool. It can be concluded that each of the studied methods evaluates an NP and is specifically used for that NP. A general risk assessment approach cannot be applied to all NPs but should be separately investigated by different processes.