Mineral Oil Mineral Oil is often the de facto choice for treating and conditioning a chopping board and for good reason. It is considered non-toxic and being low viscosity will soak deep in to the wood to protect it. Yes, mineral oil can be safely used on hand tools to protect blades and metal parts from rusting. Using a soft rag, apply a very thin film of mineral oil over the metal surface after use. Mineral oil does not go rancid or oxidize. ✅usp-grade ✅safe for babies ✅odorless and colorless ✅reduces rashes ✅base oil for massage/spa oil,lotion and cream formulation ✅moisturizer ✅softens cracked heel ✅dislogded ear wax ✅removed oil based make up ✅can be use to clean wooden utensils USP grade meets or exceeds requirements of the United States Pharmacopeia (USP). This grade is acceptable for food, drug, or medicinal use.