Scrub the dickins out of it with steel wool or a green scrubby pad and mild soap.

When the grime is gone, let it dry, sand it lightly and re-oil the wood with a food-grade opil, like mineral oil.

Mineral oil isn't something I would use on my salad bowl....but a light coating of olive oil is.
Sometimes rubbing alcohol on a green scrubber will soften that stickey goo.
Linda C

here's a link about oiling your bowl

Here is a link that might be useful: wooden bowl

I know that some makers of bowls say to recondition with mineral oil, but I don't want mineral oil used on items I put my food into, or on. I use mineral oil on my skin, but not in my food.
I have a stack of wooden bowls, none of them newer than 30 years. Two I know for sure belonged to my grandmother, who would celebrate her 122 birthday next week if she were alive. I have never put anything but vegetable oils on them. They are not sticky nor gummy and I feel safe eating a salad out of them.
Linda C

Seems to be a bit of confusion about mineral oil.. there is a mineral oil folks use on skin but there is also a food safe mineral oil that is specifically made for wooden food utensils/bowls/cutting boards. Not saying it is better or anything than olive oil. I know which I would pick ;) Just wanted to clarify it is the food safe version of mineral oil that is some times recommended for wooden things and you must be sure it is that type that you purchase if you go that way.

I would use linseed oil. It's what I use on my cutting boards.

John Boos should sell an appropriate food safe oil.