Lead is one of the oldest metals used by humankind--some historians have theorized that the downfall of the Roman Empire was expedited by the debilitating effects on its citizens of drinking water carried in lead pipes. It is the most corrosion resistant of the common metals; buildings built in Europe four centuries ago still stand under their original lead roofs.
Today's major use of lead is in lead-acid storage batteries. The electrical systems of vehicles, ships, and aircraft depend on such batteries for startup, and, in some cases, batteries provide the actual motive power. Other batteries provide standby electrical power for emergencies, and very large lead-acid systems are designed to provide "peaking" power in such applications as commercial power networks and subway systems. An increasing use is in the uninterruptible power supply systems necessary for voltage control and emergency power in critical computer storage systems. Lead in gasoline, once the second largest use of lead in the United States, has been virtually phased out to eliminate the health hazard it was found to present.
Nontransportation uses for lead include increasing use for soundproofing in office buildings, schools, and hotels. It is widely used in hospitals to block X-ray and gamma radiation and is employed to shield against nuclear radiation both in permanent installations and when nuclear material is being transported.
A major problem with lead in some uses is its toxicity because accumulation of even minute quantities in the aqueous system of the body can cause permanent brain damage and/or central nervous system disability, liver and kidney damage, and even death. Even the use of lead shot for hunting geese, ducks, and other migratory waterfowl is declining because of lead's toxic effect on the marine life chain.
Besides being a major user of lead, the United States is a major mine producer and by far the world's leading metal producer. Missouri is by far the main producing State. Because of the great number of scrap batteries that become available each year, recycled lead supplies more than 60% of our annual demand. The leading foreign mine producers, with output about equal to that of the United States, are Australia and the former U.S.S.R. The leading foreign metal producers are the former U.S.S.R., the United Kingdom, the Federal Republic of Germany, and Japan. These four countries, together with the United States, account for about one-half of the world's refined lead production.
Lead's toxicity presents problems in producing it as well as in using it, and emissions from lead smelters and refineries are closely regulated, as are worker blood-lead levels and inplant permissible exposure limits in all lead and lead oxide producing, lead-acid battery manufacturing, and other lead products plants. This adds to the cost of producing lead but is necessary to protect both the general public health and the health of lead industry workers. Early in 1991, after 2 years of intense study, the Environmental Protection Agency completed a long-range, multimedia pollution prevention strategy, which will result in significantly stricter regulations being imposed on both the producing and consuming sectors of the lead industry during the next several years.
- Table 1.--Salient lead statistics
- Table 2.--Lead supply-demand relationships
- Table 3.--U.S. primary lead refinery production
- Table 4.--Stocks of lead at consumer and secondary smelters in the United States, December 31
- Table 5.--Average annual price of lead
- Table 6.--U.S. imports for consumption of lead, by country