 White lead is the chemical compound Pb3 (CO3)2(OH)2. It was formerly used as an ingredient for lead paint and a cosmetic called Venetian Ceruse, because its opaque quality made it a good pigment. However, it tended to cause lead poisoning, and its use has been banned in most countries.
White lead has been the principal white of classical European oil painting. It is partly responsible for darkening of old paintings over time, because it reacts with trace amounts of hydrogen sulfide in the air, producing black lead sulfide. White lead has since been supplanted in artistic use by titanium white, which is somewhat less opaque and brilliant, but does not blacken and is not toxic.
Historically, white lead was produced by the Dutch process. This involved casting metallic lead as thin buckles. These were corroded with acid in the presence of carbon dioxide. Next they were placed in pots with a little vinegar (containing acetic acid). These were stacked up and left for six to fourteen weeks, by which time the blue-grey lead had corroded to white lead. The pots were then taken to a separating table where scraping and pounding removed the white lead from the buckles. The powder was then dried and packed for shipment.
White lead occurs naturally as a mineral, in which context it is known as hydrocerussite.
 Cerussite
Cerussite (also known as lead carbonate or white lead ore) is a mineral consisting of lead carbonate (PbCO3), and an important ore of lead. The name is from the Latin cerussa, white lead. Cerussa nativa was mentioned by Conrad Gessner in 1565, and in 1832 F. S. Beudant applied the name cruse to the mineral, whilst the present form, cerussite, is due to W. Haidinger (1845). Miners' names in early use were lead-spar and white-lead-ore.
Cerussite crystallizes in the orthorhombic system and is isomorphous with aragonite. Like aragonite it is very frequently twinned, the compound crystals being pseudo-hexagonal in form. Three crystals are usually twinned together on two faces of the prism, producing six-rayed stellate groups with the individual crystals intercrossing at angles of nearly 60°. Crystals are of frequent occurrence and they usually have very bright and smooth faces. The mineral also occurs in compact granular masses, and sometimes in fibrous forms. The mineral is usually colorless or white, sometimes grey or greenish in tint and varies from transparent to translucent with an adamantine lustre. It is very brittle, and has a conchoidal fracture. It has a Mohs hardness of 3 to 3.75 and a specific gravity of 6.5. A variety containing 7 % of zinc carbonate, replacing lead carbonate, is known as iglesiasite, from Iglesias in Sardinia, where it is found.
The mineral may be readily recognized by its characteristic twinning, in conjunction with the adamantine lustre and high specific gravity. It dissolves with effervescence in dilute nitric acid. A blowpipe test will cause it to fuse very readily, and gives indications for lead.
Venetian ceruse
Venetian ceruse, also known as "spirits of Saturn", was a skin whitening cosmetic used in the 16th century with a base of white lead. It was highly prized and widely used (by Queen Elizabeth I of England, among others), even though it was known that extensive use would cause lead poisoning, leading to severe sickness or even death.
Skin whitening
Skin whitening is a term covering a variety of cosmetic methods used to whiten the skin, in parts of East Asia, the Americas, the Middle East, and Africa.
Skin lightening or whitening is a controversial topic as it is closely intertwined with the detrimental effects on health, identity, self image and racial supremacy. See article on colonial mentality. Many skin whitening cremes are made from deadly chemicals.
Specific zones of abnormally high pigmentation such as moles and birthmarks may be depigmented to match to the surrounding skin. Conversely, in cases of vitiligo, unaffected skin may be lightened to achieve a more uniform appearance. The reason for singer Michael Jackson's change in skin is apparently vitiligo and depigmentation was used to achieve a more matching appearance.
Some people treat larger areas to lighten the natural complexion, out of esthetic preference or to avoid social/work discrimination and gain access to better income (this is true, for example, of prostitutes) or higher social position. This kind of colorism commonly occurs in India.
An additional application is genital or anal bleaching, intended to reduce the typically darker pigmentation of the genital and perianal area.
In Japan, geishas were (and still are) known for their painted white skin, which represents beauty, grace, and high social status. However, the skin-whitening products are not used in such a wide scale in Japan today. Geishas paint their skin white in geisha-based ceremonies to celebrate their culture and background.
In Iran, during the Achaemenid dynasty, farmers and civil workers used some kind of lightening lotion to keep their skin white and soft.
Today, skin whitening products are available in the form of creams, pills, soaps or lotions. The mechanism of permanent whitening is usually by the breakdown of melanin by enzymes, such as that contained in the droppings of the Japanese bush warbler or reducing agents such as Hydroquinone. Most whitening creams also contain a UV block to prevent sun damage to the skin.
Lead poisoning
Lead poisoning is a medical condition, also known as saturnism, plumbism or painter's colic, caused by increased blood lead levels. Lead may cause irreversible neurological damage as well as renal disease, cardiovascular effects, and reproductive toxicity.
Humans have been mining and using this heavy metal for thousands of years, poisoning themselves in the process due to accumulation and exposure. The dangers have also long been known. Reducing the hazard requires both individual actions and public policy regulations. Blood lead levels once considered safe are now considered hazardous, with no known threshold.
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