That's not good because I use a generic form of plastic wrap to hold heat and humidity in my enclosures. I haven't had any strange odors from it though. Ill have to find a another means of doing so. I didn't start using it until like 3 weeks after Grif became sick so I know it didn't cause his illness. I guess I haven't gotten it hot enough and some of the books on frogs I have say to use it. I haven't noticed any odd behavior. Especially since Grif has recovered.