If I have API having MDD of 25 mcg i.e. 0.025 mg than what should be the limit for genotoxic impurities as well as nitrosamine impurities?
As per standard TTC: 1.5/0.000025=60000 ppm
For Nitrosamine: 26.5/0.025=1060 ppm (considering CPCA category 1)
Limit for non genotoxic impurity is 0.1 or 0.15 % i.e. 1000 or 1500 ppm.
In this case, higher limit of GTI as well as Nitrosamine the non GTI is justified?
dear ghanshyam.joshi,
we had same questions regarding the inhaled and pMDIs products we have.
My opinion is that we should not confuse the test of nitrosamines with the test for the related substances which means that we should have different spec. limits. One for the nitrosamines and one for the non genotoxic impurities, even if the determination method could be that same.
kind regards
christos