ABSTRACT
In the risk assessment process, uncertainty may occur for different reasons; for example, a lack or a limit of knowledge about the exposure pathways of interest, the target population under consideration, the exposure scenario(s) on which the assessment is based, the models used and/or the data used. Uncertainty is an intrinsic property of risk assessment and concerns each step of the assessment process. In principle, the presence of uncertainties precludes neither risk assessment nor risk management decision-making, but it does affect the result of the assessment. A considerable variety of methodological approaches to performing uncertainty analysis in risk assessment have been developed and discussed in the literature. The present step focuses on those sources of uncertainty identified at the end of the previous step for thorough assessment. The aim here is to evaluate the range of possible values of each uncertainty source.
