Wipe the washer out with a damp paper towel and throw it away. Do the same thing for anything else that might have glitter on it. As far as masks, do not use it, even if the group sent it to you. They may have not even given any thought to it. I know that children's pillow cases for charity should not be made with glitter fabric either. The fabric you washed with the glitter fabric can be shook out, use a lint brush on it after shaking it and wash it again.