Billev Pharma East can help you to calculate Health-Based Exposure Limits (HBELs) in the context of quality risk management of cross contamination during the manufacture of different products in the same manufacturing facilities. Chapters 3 and 5 of the GMP guideline have been revised to promote a science and risk-based approach and refer to a “toxicological evaluation” for establishing threshold values for risk identification. The derivation of such a threshold value (e.g. permitted daily exposure (PDE) or threshold of toxicological concern (TTC) should be the result of a structured scientific evaluation of all available pharmacological and toxicological data including both non-clinical and clinical data.