Joe2:
I believe it was indeed salad oil. But you will never, ever win this or make your point to the satisfaction of some.
My red oak (there... I said it.... I admit it) cutting board has been wonderfully resilient over the years, but I do not use it for meats of any type. It has literally seen hundreds of pounds of veggies, homemade bread, etc. on its top over the years. As advised by my "real" chef friend, it is washed with bath tub cleanser and a stainless scrub pad after each use.
For meats, my cutting board is some kind of nasty hard birch that shone when it came out of the planer, and my carving/serving board is maple.
On something as silly as cutting boards wood stuff in the kitchen, I say use what you like if it doesn't make you sick. I am sure that many of the old bowls, cutting boards and kitchen utensils that were in use for a few hundred years before the turn of century developed their patina from them animal and vegetable fats that were absorbed into the wood.
Think about a wooden ladle soup into a wooden soup bowl eaten with a wooden spoon. Yet these folks didn't have antibacterial soaps, chlorine cleanser, Mahoney's special curing walnut oils, and sadly many didn't have the luxury of choosing all their woods. Seems like they did alright in retrospect.
I am wondering why this thread hasn't started a flame war as it has in the past...
Robert