Questions and answers for marketing authorisation holders/applicants on the CHMP Opinion for the Article 5(3) of Regulation (EC) No 726/2004 referral on nitrosamine impurities in human medicinal products Appendix 1: Acceptable intakes established for N-nitrosamines Appendix 2 : Carcinogenic Potency Categorisation Approach for N-nitrosamines Appendix 3 : Enhanced Ames Test Conditions for N-nitrosamines