Since they are designed to be moisture resistant, probably nothing. Keep in mind primers were meant to be active after decades of storage in harsh environments around the world in damp/hot/freezing conditions while being tossed around in military trucks going offroad and jarring cross country delivery truck rides. They are pretty tough and difficult to deactivate.
WARNING: Please wear eye/face protection whenever handling primers.
The primers I have taken apart all have sealants and/or sealing barriers (bursting paper?) that protect the priming compound. When you look inside the primer cup, the color you see is not the color of the priming compound but rather the color of sealant/sealing barrier.
Many post they deactivate primers by soaking them in different solvents/solutions. Well, to deactivate the priming compound, you must soak past the sealant/sealing barriers and even then the solvents/solutions need to react with the priming compound to neutralize them. Looks like we have another THR myth busting in the works (Can primers be deactivated by soaking in solvents?
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As to how they are manufactured, someone more familiar with that process can comment.
Primer anvils with their respective sealing barriers felt like heavy waxed/treated paper cups and they were quite durable/not readily damaged. They were solidly pressed/glued in and difficult to remove from the priming compound.
Winchester and Magtech primers still have their paper cups inside the primer caps but Tula and PMC sealant/cups were removed (Tula anvil shows pink paper cup still attached to the anvil tip). Looking inside Tula/PMC primer caps, you can see the hard priming compound under the yellowish powdery substance.