Lead is a naturally occurring, soft, bluish-gray heavy metal. Although nearly 50% of lead used today comes from recycled materials such as car batteries, its most common source is the mineral Galena (lead sulfide) that forms as pockets or veins in carbonate rock.
Lead has been in use since ancient times. A lead statue discovered in Turkey has been dated to around 6500 BC. The Romans had indoor plumbing that was made from sheets of lead rolled into pipe. Plumbum, the Latin word for lead, is also the origin of the word plumber and the metal’s elemental symbol (Pb). Industrial emissions, combustion of leaded gasoline and widespread use of lead-based paint have all contributed to a vast amount of air, water and soil pollution in the 20th Century.