DNP has no safe level of ingestion. It acts as a proton ionophore, basically acting to enable transport of protons across the mitochondrial membrane, which in short, buggers up ATP production. ATP is the basic unit of energy for all cellular operation, be it plant or animal, anything but viruses and subviral agents (I.e viroids, small segments of genetic code which require a viral 'helper' to supply the remainder of the code required to replicate which the viroid does not possess, one of the hepatitis subtypes, hep D IIRC, is a viroid and requires coinfection with another, true virus to infect, although most viroids are not human, but plant pathogens, anyhow...)
It doesn't HAVE a 'good' dose level. Only one which is survivable in the immediate term. Thus stuff is in a class alone with for example, cyanides, azides, bongkrek acid, fluoroacetate and fluoroacetyl esters (monofluoroacetate, that is, things like di- and trifluoroacetic acid don't share the same toxicity), all these lot are mitochondrial toxins, that via one way or another disrupt cellular energy production. )
The entire reason that DNP has the effect it does, it that it shunts caloric intake away from the mechanism by which it is turned into energy, in a crude manner of speaking. In short, what goes in, doesn't come out. Not as usable energy, but instead is dissipated as useless heat. The net result is blockade of ATP synthesis.
It isn't the phenolic motif that causes the toxicity btw, its the presence of multiple nitro groups, they don't 'release their energy' within the body, thats a (fairly understandable) confusion with the world of explosives, many HEs being nitro compounds, it does make for excellent energetics, but that isn't whats happening in the case of DNP.
Got strong suspicions that para-nitroamphetamine would turn out to be a neurotoxin at least, if it didn't share the mitochondrial toxicity of polynitrated phenols, since the para-haloamphetamines (4-fluoroamphetamine excepted) are (e.g para-chloro/bromo/iodoamphetamine and the nitro group makes a good bioisostere for the halogens, as does for example, the cyano group (would bet that 4-cyanoamphetamine wouldn't be a good idea either)
Whilst the serotonergic neurotoxicity potential is likely to very likely absent in DON and 2C-N (likewise 2C-CN/DOCN) I do have my suspicions about large quantity use of DON (never heard of anyone taking 2C-N) I do know of, or rather, did know of somebody who seemed like she liked DON a lot. Sadly I can't ask her to confirm suspicions or deny them now, Girl in question is dead. Could have been other causes though. She did, afaik, use some rather nasty reagents, diborane coming to mind in particular, at times)
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