Maybe it's the material of the bra Commonly used materials are polyester, cotton, modal and health. Maybe the bra is made of sponge. After some chemical treatment, it may smell like medicine, or it may smell like medicine where it is stored. Wearing a thick sponge bra for a long time is toxic, poisoning the breast, getting breast cancer and other gynecological diseases, which are reported in the news. Buy a bra, don't wear it too thick, it should be breathable, comfortable and not tight!