Why There's Antifreeze in Your ToothPaste! Not many have the resources available that I have at present. This book is not in everyones hands. The Chemistry of household Ingredients. In soap Titanium Dioxide TiO2 is used to make clear soap white. It is an opague powder and reflects or scatters light of many frequencies, from infrared through ultraviolet. That is what makes our soaps white. Zinc oxide ZnO is another. Both can be used in cosmetics and toothpaste. Also sunblocks. Simon Quellen Field