Lead poisoning

Lead (Pb) is a natural component of the earth's crust with trace amounts existing in soil, water and plants. It has many uses, including in the manufacture of lead-acid batteries for motor vehicles and energy storage, in pigments and paints, solder, ammunition, ceramic glazes, jewelry, toys and also in some cosmetics and traditional medicines.

Lead is the most important toxic heavy element in the environment. Globally it is an abundantly distributed, important yet dangerous environmental chemical. According to WHO lead poisoning refers to excessive human exposure to lead.

Lead enters the body via ingestion or inhalation from sources such as soil, food, lead dust and contact with lead in products of everyday use and in the workplace. In the work environment, the main route of absorption of Pb and its compounds is through the respiratory system, although lead is also absorbed via the digestive system.

Lead has been used for thousands of years and its poisoning effects have been recognized for several centuries. Leaded gasoline and paints were thought to be the main sources of lead pollution in the environment.

Though its widespread use has discontinued in many countries of the world, it is still used in many industries like car repair, battery manufacturing and recycling, refining, smelting, etc. Lead is a highly poisonous metal affecting almost every organ in the body.

Lead has no biological function in the body. It accumulates in the body and affects practically all organ systems. Long-time exposure to lead has been reported to cause anemia, along with an increase in blood pressure, and that mainly in old and middle-aged people.

Lead exposure can cause chronic and debilitating health impacts in all age groups, but it is particularly harmful to young children. This is because the developing nervous system is vulnerable to the toxic effects of lead, even at levels of exposure that do not cause obvious symptoms and signs.
Lead poisoning

Chemical element: Lead

Toxic minerals are minerals that are hazardous to human health. A mineral by itself, or its components, can be toxic. Typical examples of the former are asbestos, selenium, and silica minerals; typical examples of the latter are minerals containing such toxic chemicals as arsenic, lead, mercury, or cadmium.

It is very soft, highly malleable, ductile, and a relatively poor conductor of electricity. It is very resistant to corrosion but tarnishes upon exposure to air.

Lead belongs to group 14 of the periodic table, which also includes C, Si, Ge and Sn. Lead has the most metallic characteristics of this group. The element has an atomic number of 82, an atomic mass of 207, two oxidation states (+2 and +4) and four naturally occurring isotopes (204Pb, 206Pb, 207Pb and 208Pb), of which 208Pb is the most abundant at 52% of the total mass.

The major use of lead today is for batteries. Lead also is used as a protective shield against radiation. One lead mineral that was historically used as a nat-ural dye is chrome yellow, which is toxic.

Lead is a heavy metal with a high toxicity. Lead is toxic at very low exposure levels and has acute and chronic effects on health and the environment. It can effect the nervous system, the reproductive system, and the heart and blood system. Minerals containing lead are toxic to many tissues and organs, including the heart, bones, intestines, kidneys, brain, and reproductive system. Also, lead ions inhibit enzymes neces-sary for the synthesis of hemoglobin (the oxygen car-rier in human blood). Lead poisoning causes mental retardation and neurological disorders.

Chemical element: Lead