“Moving the brush in and out forces air deeper into the tube, and, if any bacteria from your eyes come with it, the air helps those germs thrive and multiply,” Dr. Krant says. Air also causes mascara to dry out faster so it doesn’t last as long as it should.
Break it: Gently pull out the wand, moving it around inside the container and scraping the edge minimally to keep everything fresh and bacteria-free as long as possible, Dr. Krant recommends. You’ll still get a sufficient amount of product on the brush and avoid possibly contaminating the rest.