[47] It can affect the land when the bitumen is initially mined, water by its requirement of large quantities of water during separation of the oil and sand and the air due to the release of carbon dioxide and other
emissions.[48] Heavy metals such as vanadium, nickel, lead, cobalt, mercury, chromium, cadmium, arsenic, selenium, copper, manganese, iron and zinc are naturally present in oil sands and may be concentrated by the extraction process.