For any medical grants, you need a heavy set of PHD credentials. I don't believe I have stumbled across many medical research grants, as most researchers hold parties to get private investment grants.
Most of the grant provisions, demand that you have a solid business plan, some form of invested collateral, and levels of education specific to the structure of the applied grant. There are many agricultural grants, which could possibly fall into relation here. There were a few chemistry related grants, that are borderline appropriate. The rest that I saw, were all for education, teen drug prevention, emergency aide, third world assistance, or military related.
I am not saying there is nothing out there, just not on the GOV sites I researched. Building a set of contacts now, and historical use documents, would turn us into an asset that desired by anyone who does eventually get these grants. Doing like I said, seeing a doctor now, while you are still smoking analogs, and following-up with visits once off the analogs. Those collections of data, will give the groups doing the official research, a starting ground. To let them know what to look for, what to rule-out, and what is actually occurring.
Besides, being new, and unknown, it is best to be using these under a doctors supervision. Just in case. Especially if use of these devices, as a smoking replacement, extends beyond a year. (As opposed to those using them for oral flavor only, or for oral gratification of nicotine transfer.)