Boiled Linseed Oil contains "drying" agents in the form of metals. I used to use it on my flutes and I wondered why I was constantly feeling "funny" after tuning them freshly oiled. Later I discovered you can get food grade linseed oil. If you go to the local health food store, you can probably buy a quart of it for around 10 dollars. It works the same way as regular BLO, but takes longer to dry.