> The neonics were developed precisely to exploit the fact that they do NOT produce the same effects in mammals as insects.

> In summary:  This is baloney.  They do have exactly the same effect, but at a much lower dose because the affinity they have for the nicotinoid receptors in insects is greater than the affinity they have for the nicotinoid receptors in humans.  This is what your next statement says:

> Neonicotinoid insecticides display excellent selectivity profiles that are largely attributable to specificity for insect versus mammalian nAChRs  (Nicotinic acetylcholine receptors).

I don't know why you have to degenerate to using terms like "baloney". It is fully documented that neonics act on insect nAChRs but not mammalian ones. In the work quoted above, you will find more detail.

> The low affinity of neonicotinoids for vertebrate relative to insect nicotinic receptors is a major factor in their favorable toxicological profile.  The neonicotinoids and pyrethroids have higher selectivity factors for insects versus mammals than the organophosphates, methylcarbamates, and organochlorines. This is attributable to both target site specificity and detoxification.

> Neonicotinoid insecticides display excellent selectivity profiles that are largely attributable to specificity for insect versus mammalian nAChRs. Neonicotinoids and nicotinoids have common structural features but different protonation states at physiological pH. The neonicotinoids (e.g., IMI) are not protonated and selective for the insect nAChR, whereas the nicotinoids (e.g., nicotine) are cationic in nature and consequently selective for the mammalian nAChR. 

> The neonicotinoids are nicotinic agonists that interact with the nAChR in a *very different way than nicotine*, which confers selectivity to insects versus mammals. The neonicotinoids are not protonated but instead have an electronegative tip consisting of a nitro or cyano pharmacophore that imparts potency and selectivity, presumably by binding to a unique cationic subsite of the insect receptor. This is in marked contrast to the action of protonated nicotinoids, which require a cation-π interaction for binding to the vertebrate receptor. These differences provide the neonicotinoids with favorable toxicological profiles.

NEONICOTINOID INSECTICIDE TOXICOLOGY: Mechanisms of Selective Action
Motohiro Tomizawa and John E. Casida
Environmental Chemistry and Toxicology Laboratory, Department of Environmental Science, Policy and Management, University of California, Berkeley, California 94720-3112; email: [log in to unmask], [log in to unmask]

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