Same issue here. Glad to read on this topic. I couldn’t find much online.
That said I stumbled upon this, that says washable sticky lint rollers work wonder to remove the filth on sticky parts:
And cover your push with a cloth after use. Light seems to also have an incidence.
Edit: Washable roller in action : https://www.youtube.com/watch?v=zHgV2g691o8&feature=youtu.be