The talcum powder doesn't need to contain asbestos to cause ovarian cancer. It'll do it on its own.

This has been known for a long time, but some of the talcum powder manufacturers are sitting on non-aesbestos-contaminated mines. To delay the inevitable bans (and to allow them to charge a premium), they heavily push the "aesbestos-contaminated talcum powder causes cancer" story. It is technically true, but intentionally misleading.