In light of the uncertainties, one could argue that we
should abstain from such impact assessment. We
disagree. First, there is abundant evidence that current
levels of air pollution have adverse health effects, thus
the impact cannot be zero.26 From a public-health
perspective it is therefore an ethical consequence to
estimate and communicate the impact to the public.
Second, societies have to make important decisions at
the time. To abstain from impact assessment, given the
many uncertainties, would promote decisions without
consideration of aspects of public health. This is
particularly true for environmentally sensitive decisions.
Third, we consider the participation of epidemiologists
and other sciences in this interdisciplinary process of
impact assessment as crucial.27