The toilet powder commonly known as "rice powder"—often labeled "Poudre de Riz" or "Fleur de Riz"—seldom is what its name declares, according to Charles H. La Wall,3 chemist to the dairy and food commissioner of Pennsylvania. Out of sixteen samples of so-called rice powder examined by him, only two consisted entirely of rice (unfortunately La Wall does not name the brands), and only six contained any rice at all. Talc, corn starch, zinc oxid, chalk and bismuth subnitrate were the substances found replacing rice flour wholly or in part.
La Wall's attention was first directed toward substitutions and adulterations by a case in which a physician had difficulty in establishing a diagnosis. A face powder, alleged to consist of rice flour, fell under suspicion, and was found to contain zinc oxid, talc and corn starch, but no rice. The zinc oxid proved to be the disturbing factor. La Wall
RICE POWDERS AND FACE POWDERS. JAMA. 1915;LXV(5):431-432. doi:10.1001/jama.1915.02580050059020