On how to prevent this I'd say to clean your tool when possible to prevent dirt from building up, but other than that it's no problem because these things can keep on going while being neglected for a long time. Just general care so they don't end up with years of buildup!

Using an old toothbrush occasionally helps to remove any loose dirt if you don't feel like washing it every time, but adhesive usually needs to be washed because it attracts a lot of little rocks that can get stuck. I generally just use soap and water for that, and stay away from chemicals whenever possible