What do I do wih stained panties?

i have heavy periods so sometimes i stain my underwear, and the blood never comes out. I have like 20 dirty pairs sitting in this old shoe box (hiding it from my mom). I am moving to a new country next month and am scared the packers will find them or somethiing bad will happen. So how do i get rid of them, the stains are too old to wash out. Do i just throw them in the trash??? or will someone find them and find out they are mine by the DNA in the blood. help!! what do i do???