Update of time extrapolation factors for risk assessment –the benefit of combined databases and probabilistic analyses

Introduction

In regulatory risk assessment, extrapolation factors (EFs) are used to extrapolate from experimental conditions (animal studies) to human exposure.
Time extrapolation: a short time study is available, but safety assessment for chronic exposure conditions is required.
The NO(A)EL (no observed (adverse) effect level) of the long term study is then estimated by applying the corresponding EF.