Dnp is not carcinogenic. Fonz has addressed this many times.
Dnp does not cause cataracts. If you look at the study that purports the incidence of cataracts in women, and compare it to the population at large, if anything it proves that dnp is anti-cataract.
Yes, it does affect the thyroid, but in a similar way that the keto diet does. It only takes a few days (a couple of weeks) for your thyroid to recover.
Usnic acid...hmmm, I remember something about Dan Duchaine talking about this on the lowcarb list I was on. I really never gave it much thought. I am pretty sure I read a study on it where it was shown to not cause any kind of chromosomal damage. I forget what the test is called, but it's used to gauge this type of activity. Plus I think there are veggies that have usnic acid in them, so I highly doubt there is much potential for damage there.
Now, you have got me interested. Does anybody sell usnic acid? Is it still legal? And how effective is it vs. dnp?
I would think the main problem is that if it is legal, it would be more expensive than dnp is now, lol.