My urine like everyone else's contains potassium and can be used to create gunpowder - does this mean I am enabling terrorists to blow people up every time I take a leak?

If you and millions of other people captured, packaged, and transmitted that urine to a central urine clearinghouse (similar to how Google Photos works), then yes. Innocuous activities can easily be made dangerous when those activities are centralized and scaled up to a level involving/affecting hundreds of millions of people.