We are actively working with Mr. Ishibashi of Onzow to investigate these questions more deeply. Early experiments show very fresh units of Zerodust do not appear to leave any paraffin oil after application.
Anyone Still Using Zerodust
Haven’t heard anything since the original scare, but I stopped using it. I think I never had a problem because I always swipe with LP#9 between sides, as per Brooks Berdan’s advice. One recent video said Wally discovered some type of oil on the ZD. I regularly cleaned mine with dishwashing liquid, which could have removed any residue.