DIY Leather Cleaner & Conditioner: Simply mix up cup olive oil, cup white vinegar, and a couple of drops of your favorite essential oil in a clean empty spray bottle and lightly spray your leather surface. try it to make sure it is safe for your leather.
How to Clean a Leather Couch - a great step by step article for toxin free leather cleaning. Ingredients for cleaner: 1 part vinegar 1 part water. Leather conditioner: 1 part white vinegar and 1 part linseed oil