Investigational

The dilemma of lacking data is
a majorhindranceforusing
NOEL‘s and uncertainty factors!
NOVARTIS
In vitro + in vivo genotoxicity assays are hazard identification
tests, and thus do not provide data suitable for use in
quantitative risk assessment
Approach proposed (use of NOEL + UF) is unlikely to be
feasible in most circumstances (no adequate data)!
Pragmatic approach is needed (amount of impurity in µg/day
considered as generally acceptable intake level)
‣ The NOEL / UF approach can be used for toxicologically well
characterized compounds, a condition, which is normally not
met for impurities
L. Müller, Swissmedic, 21-Oct-2003