@Naiffer_Host can you please take initiative of preparing a list for the vendors having available in stock nitrosamine impurity standard particularly for NDSRI (Nitrosamine Drug Substance Related Impurity), so that if anyone want to analyse their API or Drug Product, then they can directly contact to the vendor for procurement. This will helps to save time for analysis. Anyone who has procured NDSRIs from any vendor can update that dynamic list. This is required because some of the NDSRIs are already synthesised at particular vendor and they already had experience to synthesis it which might not be possible by other vendors to synthesis it with greater purity. Thanks.
@Naiffer_Host Or you can create a community for the vendors who are supplying nitrosamine standard by inviting them to join the community and periodically they will update about their new synthesis and in stock product.