Baby powder is also known as talcum powder, when it consists primarily of talcum/talc. Talc has an eerie similarity with absestos which has the potential to be carcinogenic. Because of this, there are rules which limit the amount of fibers, like the ones present in asbestos, present in talcum powder. Many argue that talcum powder should not be used at all. This is because of a study conducted during the last decade which reported that talc caused tumerous growth in the test animals, even when it was used without any fibers (the absestos like ones which are carcinogenic in nature).
Another study found a link between the usage of talc in the female genital area and the occurrence of ovarian cancer. According to that study, there was a direct link between these two. The same study reports that talcum particles move through the body’s reproductive system, and will settle down somewhere near the ovary linings. Yet another reason that talc is considered harmful is that it is harmful to the lungs. The proof for this is the high occurrence of lung cancer among the miners who mine talc. Kids are also at high risk of developing lung infections, as a result of ingesting talcum powder.
So, in conclusion: yes, talcum powder does prevent diaper rashes, and it does have many cosmetic uses. But, when baby powder is composed mainly of talc, the risks outweigh the benefits, according to many studies. So, it may be prudent to minimize the usage of talcum powder, especially for small babies!