Design and Development of Comprehensive Exposure Scenarios to Chemicals

In the regulation concerning the Registration, Evaluation, Authorization and Restriction of Chemicals (REACH), the supplier of a substance or a preparation is required to ensure that exposure to these substances throughout the entire life-cycle is below the threshold level beyond which adverse effects may occur. Although scenarios of exposure to chemicals throughout the life-cycle of chemicals are needed for risk management, there is no comprehensive database for the making of exposure scenarios. In this study, a prototype of comprehensive exposure scenarios throughout the life-cycle of chemicals was developed by extracting exposure scenarios from laws and regulations related to emission of or exposure to chemicals in Japan, risk assessment documents, and exposure assessment tools. Separate databases of emission sources and exposure scenarios after chemical releases were constructed in order to assemble a database of comprehensive scenarios of exposure of humans to chemicals. Further studies are needed to apply these databases in risk-based screening for human health.