Are these removable?

If you look closely you will see some tiny dots. Even though not visible from camera they are all over the back of the phone and im almost 100%sure it’s from the metal powder from the place I work. Even though I use a case they slip through it forcing me for a year now to take the case of every 2-3 days to clean the phone but apparently they got into it? No matter how hard I rub it they won’t go away but I’m here hoping for a trick or something Phone is 15 pro titanium blue