It's not hard to find. The concentration for an IV DMT dose is 1000 times greater than what is found in your body after you're high. And IV doesn't need to be nearly as concentrated as what you need to get high from, for example, smoking.
So if you took a regular, safe, DMT dose and diluted it a couple thousand times, I doubt you'd get arrested for it. But that's not going to get anyone high.
Really though this is just common sense. Concentrations of drugs within your body are going to be way smaller than what you need to get high off of them. That's just the way drugs operate.