If you think of old items, from 1960 and -70´s.
Do you think there is anything from 1960 that is still clean, not even dusty? - No, there isn´t.
Dust and dirt get more or less everywhere that isn´t vaccum-sealed. Old movies are always a more or less dusty/dirty, it is inevitable. How dirty they are depend on how often they were viewed with a projector and how they have been stored.
We always clean all old films we receive for transfer, it is included in the price. Cleaning is necessary if you want a good result from old film transfers.
We only use chemicals approved by Kodak/Hama for cleaning of motion picture film.