Capper Pass and Son

Capper Pass and Son Ltd. was a British smelting and refining company specialising in non-ferrous metal refining, particularly tin. Originally established in Bristol in the early 1800s, the company relocated to a site on the banks of the Humber Estuary at Melton, East Riding of Yorkshire, in the 1930s, with the Bristol factories closing in the 1960s. Rio Tinto Zinc acquired the firm in the 1960s.

The Melton plant was a tin smelter of worldwide significance, producing 10% of world output at its peak. By-products of the tin refining process including arsenic caused local pollution, and in the 1980s an additional radioactive hazard due to polonium was discovered. Emissions from the Melton plant were implicated in a child cancer cluster in East Yorkshire; as of 2012 a link has not been scientifically established. The plant's owners Rio Tinto Zinc became involved in long running litigation due to diseases amongst the plant's workers, as well as those in the surrounding area. RTZ paid compensation to 29 ex-employees with lung conditions in 2002 after two decades of denying responsibility.

The Melton plant closed in 1991; its site was cleared and redeveloped for industrial use.