But I don't know how I came to the conclusion that some plastics will soften and deform above 70 degrees, but 70 degrees will never decompose and release harmful substances. Most plastics will decompose above 200 degrees, and a few will decompose around 150 degrees, but these will not be used for food packaging.

So as long as it is not directly roasted with fire, it is safe. Special containers should be used for microwave heating.