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Though elemental fluorine (F 2) is very rare in everyday life, fluorine-containing compounds such as fluorite occur naturally as minerals. Naturally occurring organofluorine compounds are extremely rare. Man-made fluoride compounds are common and are used in medicines, pesticides, and materials.
Pure fluorite is colourless and transparent, both in visible and ultraviolet light, but impurities usually make it a colorful mineral and the stone has ornamental and lapidary uses. Industrially, fluorite is used as a flux for smelting, and in the production of certain glasses and enamels.
The main uses of fluoride, in terms of volume, are in the production of cryolite, Na 3 AlF 6. It is used in aluminium smelting. Formerly, it was mined, but now it is derived from hydrogen fluoride. Fluorite is used on a large scale to separate slag in steel-making. Mined fluorite (CaF 2) is a commodity chemical used in steel-making.
Referring to a common salt of fluoride, sodium fluoride (NaF), the lethal dose for most adult humans is estimated at 5 to 10 g (which is equivalent to 32 to 64 mg elemental fluoride/kg body weight). [ 2 ] [ 3 ] [ 4 ] Ingestion of fluoride can produce gastrointestinal discomfort at doses at least 15 to 20 times lower (0.2–0.3 mg/kg or 10 to 15 ...
The skin weighs an average of four kilograms, covers an area of two square metres, and is made of three distinct layers: the epidermis, dermis, and subcutaneous tissue. [1] The two main types of human skin are: glabrous skin, the hairless skin on the palms and soles (also referred to as the "palmoplantar" surfaces), and hair-bearing skin. [3]
The four organogenic elements, namely carbon, hydrogen, oxygen, and nitrogen , that comprise roughly 96% of the human body by weight, [7] are usually not considered as minerals (nutrient). In fact, in nutrition, the term "mineral" refers more generally to all the other functional and structural elements found in living organisms.
Ichthyosis vulgaris (also known as "autosomal dominant ichthyosis" [1] and "Ichthyosis simplex" [1]) is a skin disorder causing dry, scaly skin.It is the most common form, and one of the mildest forms, of ichthyosis, [2] [3]: 486 affecting around 1 in 250 people. [4]
The disease is named because it is a porphyria that often presents with skin manifestations later in life. The disorder results from low levels of the enzyme responsible for the fifth step in heme production. Heme is a vital molecule for all of the body's organs. It is a component of hemoglobin, the molecule that carries oxygen in the blood.