Coolant, honing oil, kerosene, you name it, my hands have been soaking it up for many, many years now. First when I started out as a Tool & Die Apprentice polishing mold cavity and now, when I'm polishing my knives.
Like Nathan, I started to wonder what all of the petroleum based products soaking into my skin was doing to me in the long term.
Early this summer I started using regular old vegetable oil as my blade polishing/honing oil. Its probably not the ideal stuff to use (viscosity wise), being a little thicker than the typical honing oil, but I'll tell ya, in my mind huh1 I feel a lot better about using it.
If you're anything like me, your hands are literally saturated in whatever it is you're using by the time that blade is looking good.
I know this is a bit off topic than Nicks mechanical dream but hey, it works for me
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