Crayola Air-Dry Clay Tips for Use

if this is similar AT ALL to what you're using, i think the last paragraph means you shouldn't use it with flame, as it's not good to inhale the fumes. probably not as bad as polymer clay, but i don't think you should use any clay that's not covered in glaze (glass). raw clay (even air-dried standard clay for pottery class) has aluminum in it (aluminum silicate = potter class clay). when it's fired it changes to... forgot the actual name (other than "bisque") but then it's okay to smoke out of.