Swarf.

A mate tells a tale of a summer job he had in a factory when he was a student. Another lad there wasn't intimidated by all the hard, brassy women who worked on the floor and used to be really mouthy to them.
They must have got sick of his relentless cheek because on his last day they caught him, stripped him naked, covered him in swarfega and chucked him in a skip full of swarf.