As far a human olfactory? It's not really a question anyone can answer.. You could smell it from a mile away if the wind is right and a particle happens to come in contact with your olfactories.
But as a rule of thumb, I would say after a city block you should be safe.. But if the wind is blowing right, maybe farther..
But as for dogs, well I don't think anyone can answer that. Dogs don't type