While I agree the number is suspect, I'd simply cite the source of the number "_fill in the blank_ officials claim that almost half a million will die" then hoist them by their own petard. If they make the claim that half a million will die while there is an effective, alternative means of harm reduction which they discount or dismiss, then they should have to answer to why they take that stance given the number of lives they say will be lost.
I think it works as a rhetorical device but must be clearly stipulated as such. Otherwise, it does read as "I'm from the vaping community, but I parrot ANTZ logic in hopes of helping all vapers."
It ought to be stated along lines of, "according to the propagandists, half a million people will die this year from smoking. These same propagandists tell us about the grave dangers that come from vaping, while also saying the data is inconclusive. Whereas real science continues to weigh in weekly on eCigs and has been shut down on the other bit of data regarding smoking/smokers. Please don't let real science be shut down on vaping, which is clearly helping reduce cigarette consumption and in many cases leading to cessation where some smokers would've sworn, just a decade ago, that such a feat was impossible."
If stick to parroting with out stipulating that you are using it as a rhetorical device, then I'm thinking in 10 to 30 years, you may be one who is touting the idea that vaping kills 200,000 people yearly. Cause surely vapers will one day die and ANTZ will make it abundantly clear that their death was caused by vaping.