Yes, dubbin is made from natural ingredients, so it won't cause any health problems or damage your footwear if you use it properly. That being said, there are some precautions you should take to prevent potential negative effects on your boots, shoes, or other items made from leather. Since dubbin has oil elements, it may darken light-colored boots over time - this is why it isn't recommended for white items. You should also avoid using dubbin on suede or nubuck because it could damage the upper layer of these materials.