Lead and Society

Lead (from the Latin plumbum) is a chemical element with the symbol Pb, atomic number 82 (82 protons and 82 electrons), with atomic mass equal to 207,2 u, belonging to group 14 of the periodic classification of chemical elements. At room temperature, lead is a solid.

It is a toxic, heavy, soft and malleable metal and a poor conductor of electricity. It is whitish-blue in color when recently cut; however, it takes on a grayish hue when exposed to the air. It is used in construction, acid batteries, munitions, protection against X-rays, and is part of the metallic alloys to produce welds, fuses, electric cable coating, anti-friction materials, typographic metals, etc. Lead has the highest atomic number of all the stable elements.

It is a metal that has been known and used since antiquity. It is suspected that lead was being used by humans for at least 7000 years, because it was (and still is) very common in nature and easy to extract. It is also easy to work with because it is highly malleable, ductile and has a low fusion point.

Lead was mentioned in the "Book of Exodus". The oldest piece of lead discovered by archeologists dates back to 3800 B.C. and is kept at the British Museum. Around 3000 B.C. there is evidence that the Chinese already produced this metal. There are also indications that the Phoenicians used lead in 2000 B.C. Lead pipes with the insignia of Roman emperors, from 300 B.C., are still in use. Alchemists thought that lead was the oldest of the metals and associated this metal with the planet Saturn. Beginning 700 A.D., the Germans began to exploit this metal, together with silver, in the mines in the Hartz mountains, in the Rhine River valley and in Bohemia, beginning in the 8th century. In Great Britain, beginning in the 17th century, principally in the regions of Derbyshire and Wales, the foundries for this metal prospered.

The symbol for lead, "Pb", is an abbreviation of the Latin word plumbum.