Sorry! Now I found it. You have to go to "Order product". There it tells how to package your old blades and how to send them in. The new blades are not cheap, but I'd much rather pay to get the old blades recycled, than to throw them into the normal recycling. I think they are quite dangerous.
And I am a recycling fanatic. I won't throw anything away that someone else might have a use for. That's why I'm quilting. LOL I'm just recycling someone else's rejects, UFO's, no longer wanted fabric, etc. I very seldom buy new fabric.