in the same manner as an ingredient under subsection (a), if the contaminant is present in a personal care product in any quantity exceeding one half of one percent of the content of the product by weight. (d) Labeling of nanomaterials in cosmetics The Secretary may require that— (1) minerals and other particulate ingredients be labeled as nano-scale on a cosmetic ingredient label or list if not less than 1 percent of the ingredient particles in the cosmetic are 100 nanometers or smaller in not less than 1 dimension