How do i clean this?

[50000 monkeys]

Hi all

Last week i had my car in the garage to have the clutch changed. A few days later i happened to feel the bodywork and it was rough, asthough it had just been rubbed down. I could see it was covered with some sort of light red dust and i now remember the garage working on a red camper in the next bay. The thing is i have washed it and even though it looks ok it is still there. If i wet my finger and rub the paint for a bit, it clears a spot and looks like a pencil rubber on paper. It is still smooth and shiny underneath.

Is there any product i can buy to clean this without damaging the paint ?

Thanx