I think that if diaper rash cream were a culprit that the story would have been about zinc, and it was not. It was about denture cream containing zinc. Big difference. We absorb alot of things through the skin, but there is a huge difference between how a bottom absorbs and how a mucus membrane aborbs, and babys do not swallow in the general vancinty of where we apply it. Frankly, babies don't even wear it that long a time in their lives, and most don't have it on all the time, just the few times in their lives that they end up with a rash. We just don't need to worry about this, why heap on one more thing? There is just nothing here to talk about. Taking any supplement orally for some pie in the sky result, and ending up poisoned, denture cream use, and babies bottoms are just not even of the same family. How about this...the paper in cigarettes contains additonal toxins that cause smokers some of their issues with emphasema...so...get rid of that paper in your printer, and all your books, it "might" have some toxins too! Neither is logical.
If it bothers you, use something without zinc. Your hair dryer is the best diaper rash ender that was ever invented. No worries about what is in that tube.
M.