Talcum powder:

 The talcum powder  which is widely used to keep one dry, may cause ovarian cancer if applied to the female genitals. Particles from sanitary napkins, diaphragms, condoms and talcum power applications could travel through the vagina, uterus and fallopian tubes to the ovaries. An analysis of data from 16 studies found a 30 percent rise in ovarian cancer risk among talcum users. A safe alternative is cornstarch powder, which is not linked to cancer.