that doesn't sound good, unfortunately... a white soft powder that's sort of a thin film could be a bloom and is not considered harmful at all ... look up cigar bloom .. its more like an opaque coloring .. but it doesn't appear in dots, that is possibly bad news .. how were you storing it, did it get too humid? I have used these packets called "Save My Stash" and they are pretty bulletproof for keeping herbs at the right humidity level. I would do some research and you definitely might have to trash that weed if it doesn't seem safe.imp: