The use of nanomaterials in industrial and commercial applications is growing, and official reports concerning the possible environmental and health effects of nanoparticles are steadily increasing. An understanding of the potential toxicity of nanomaterials is important for creating sustainable and safe nanotechnologies. To test the cytotoxicity of nanomaterials, quantitative and qualitative analyses of raw nanomaterials should be priorities. However, the fundamental properties of raw materials will change compared to those of aged materials in biological media due to the interaction between nanomaterials and media composition. Therefore, the correlation and interdependence between pristine physicochemical properties (PChem) of raw nanomaterials before the toxicity test and aged PChem in biological media were evaluated using modified test guidelines originally suggested by the OECD WPMN (Organization for Economic Cooperation and Development, Working Party on Manufactured Nanomaterials) for peer-reviewed papers concerning silver nanoparticles, during the period of 2005 to 2010. In addition, we investigated whether the suggested analysis tools are applicable to define the PChem of AgNPs with regard to cytotoxicity.