The global leather industry slaughters more than one billion animals for their skins each year. Leather commonly comes from cattle and calves, and from other animals slaughtered for meat such as horses, sheep, lambs, goats, and pigs. Wild animals are also hunted for their skins. Kangaroos can also be commercially shot purely for their skins in Western Australia and Queensland (skin-only commercial hunting is banned in other Australian jurisdictions). Other species hunted worldwide for their skins include zebras, boars, elephants, crocodiles, and lizards. Additionally, the modern process of tanning, involves toxic substances and pollutants.