Hi Naifer,
I have just recently come across a very interesting and exhaustive evaluation of the risk of the packaging material. In summary I could say that based on the paper (case by case approach is recommended):
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Foils without nitrocellulose + any combination of primer, lacquer, aluminium and sealing method have no risk. Nitrocellulose is the source of nitrosating agents.
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Foils with nitrocellulose in combination with any primer, lacquer, aluminium and sealing method can form nitrosamines. Nitrosamines would be present outside part of the blister and a minor quantity of it can actually be volatilized inside the blister cavity.
The contribution is very low, but since we control nitrosamines in the ng scale. For some cases it could be of importance. Also, this is asumming there is a source of amines (mostly the printing ink as Not Intentionally Added Substances)
Nitrocellulose blister material as a source of N-nitrosamine contamination of pharmaceutical drug products - ScienceDirect Not sure if there is a free access version.