some types of celluloid are much more prone to this type of off-gassing and deterioration than others. Multi-colored handles and some of the transluscent stuff was the worst, in my opinion. I still think celluloid is really nice stuff, but it should be kept away from UV light and heat to help preserve it. Celluloid is actually quite durable and will last for many decades, but some will eventually breakdown and cause problems, so razor collections should ALWAYS be checked very frequently. One razor with celluloid rot in a box with others can ruin everything in the box. If you ever noticed, some of the 7 day sets have one razor that's horribly rusted and the razors have diminishing rust damage, the farther away they are set from the razor that caused the problem. Also, you will notice a rust pattern that coincides with a discoloration or what appears to be a blemish in the celluloid. As it breaks down, it often changes color or texture and becomes very, very brittle. Slightly bend it and it will break like it was made of thin hard candy.