Criteria and Application on the Use of Nontesting Methods within a Weight of Evidence Strategy

Nontesting methods (NTM) proved to be a valuable resource for risk assessment of chemical substances. Indeed, they can be particularly useful when the information provided by different sources was integrated to increase the confidence in the final result. This integration can be sometimes difficult because different methods can lead to conflicting results, and because a clear guideline for integrating information from different sources was not available in the recent past. In this chapter, we present and discuss the recently published guideline from EFSA for integrating and weighting evidence for scientific assessment. Moreover, a practical example on the application of these integration principles on evidence from different in silico models was shown for the assessment of bioconcentration factor (BCF). This example represents a demonstration of the suitability and effectiveness of in silico methods for risk assessment, as well as a practical guide to end-users to perform similar analyses on likely hazardous chemicals.