Development of the Initial Risk Assessment Method (3): Development of Pre-screening Method and Validation by Comparison with the Results of the Initial Risk Assessment

A pre-screening method was investigated to prioritize the chemicals specified by PRTR for the Initial Risk Assessment (IRA) in order to screen the chemical risk more efficiently. In this study, the prioritization of the chemicals was attempted by calculating the Priority Grade (PG) values, which were obtained by multiplying the hazard score by the exposure score derived from PRTR data. The PG values of PRTR chemicals were analyzed with the Pseudo-Risk Map, in which the hazard and the exposure scores were plotted against horizontal and vertical axis, respectively. The Pseudo-Risk Map showed that larger the PG values of the chemicals were, earlier in the order the IRA was conducted. In addition, the prioritization of the chemicals in terms of the ecological aspect was also achieved by omitting human health effects from the hazard score, and by utilizing only emission volumes to public water. Since PG values apparently being paralleled with the results obtained from IRA for 100 chemicals, the present study provides effective methodology not only for one of the priority setting but also for the pre-screening.