my first trip to Bangkok my friends who were living there at the time asked me to bring carpet cleaner with me, same deal, white and powdered...
I agreed and went to pack it and thought to myself, hmmm, what if this explodes in my suitcase, well let me vacuum seal it instead. I stood back looking at what I just created, a vacuum sealed container filled with white powder that I believed the country of Thailand did not have, then it dawned on me, that A. I don't speak Thai, and B. I don't feel like trying to explain why I have a white powdered substance in my bag if I'm asked and C. Who would believe me anyway? Left it home, told them to burn the carpet.