"Liquid nicotine" is ringing all manner of alarm bells for me. It sounds like the reporter believes you are, literally, selling 100% liquid nicotine.
Make clear that pure nicotine is deadly poison, and that you are not selling liquid nicotine. You are selling juice to be used with various
vaping devices.
Make crystal clear the contents of your juice. If it is, say, 82% vg, let him know what vg is, and let him know that it is harmless. Tell him what's in your flavorings. Tell him that the juice is only 8% (or whatever) nicotine. Tell him seomthing about the manufacturing process for the juice, etc. Get him away from "liquid nicotine" thing.
I wouldn't even mention poisoning statistics, etc., but I'd have them available if he brings it up. You might want to let him know the types of people who walk into your store, point out some favorite juices, explain the process smokers go through in making the switch to
vaping. Point out some success stories.
Be armed with statistics, research, but I would sound the guy out first.