Painter's boiled linseed oil is treated to help it dry, and lead was widely used. An exothermic reaction helps it to dry out an oil painting, but too fast and the paint cracks so they juggle the adulterants to create a slow drying balance.
We use linseed oil by the gallon (well, 5ltr containers
) in the workshops, it's hard to beat it for woodcare.
I'm not fond of the thought of ingesting mineral oil, regardless of how safe it's supposed to be, so if I think my spoons need oiled I use something like grapeseed. It's pretty stable, is absorbed well, is a basic carrier oil for massage and aromatherapy and it's sold for food use in Tesco and the like.
cheers,
M