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61-583: Lanolin's role in nature is to protect wool and skin from climate and the environment; it also plays a role in skin ( integumental ) hygiene. Lanolin and its derivatives are used in the protection, treatment, and beautification of human skin. A typical high-purity grade of lanolin is composed predominantly of long chain waxy esters (approximately 97% by weight) with the remainder being lanolin alcohols , lanolin acids and lanolin hydrocarbons . An estimated 8,000 to 20,000 different types of lanolin esters are present in lanolin, resulting from combinations between

122-446: A fibrous protein that aids in skin protection, is responsible for the formation of the epidermal water barrier by making and secreting lipids . The majority of the skin on the human body is keratinized, with the exception of the lining of mucous membranes , such as the inside of the mouth. Non-keratinized cells allow water to "stay" atop the structure. The protein keratin stiffens epidermal tissue to form fingernails . Nails grow from

183-442: A high purity grade of lanolin was found to be significantly superior to petrolatum in assisting the healing of superficial wounds. Integumentary system The integumentary system is the set of organs forming the outermost layer of an animal's body. It comprises the skin and its appendages, which act as a physical barrier between the external environment and the internal environment that it serves to protect and maintain

244-478: A lubricant grease where corrosion would otherwise be a problem. 7-Dehydrocholesterol from lanolin is used as a raw material for producing vitamin D 3 by irradiation with ultraviolet light. Baseball players often use it to soften and break in their baseball gloves ( shaving cream with lanolin is popularly used for this). Anhydrous liquid lanolin, combined with parabens , has been used in trials as artificial tears to treat dry eye . Anhydrous lanolin

305-414: A number of important chemical and physical similarities to human stratum corneum lipids; the lipids which help regulate the rate of water loss across the epidermis and govern the hydration state of the skin. Cryogenic scanning electron microscopy has shown that lanolin, like human stratum corneum lipids, consists of a mass of liquid crystalline material. Cross-polarised light microscopy has shown

366-588: A resin which melts at about room temperature and usually has a potency of 25 000 000 to 30 000 000  International Units/gram . [REDACTED] Cholecalciferol is also produced industrially for use in vitamin supplements from lichens , which is suitable for vegans. Cholecalciferol is very sensitive to UV radiation and will rapidly, but reversibly, break down to form supra-sterols, which can further irreversibly convert to ergosterol . Rodents are somewhat more susceptible to high doses than other species, and cholecalciferol has been used in poison bait for

427-459: A rich source of cholesterol (an important skin lipid) and are powerful water-in-oil emulsifiers ; they have been used extensively in skincare products for over 100 years. Approximately 40% of the acids derived from lanolin are alpha-hydroxy acids (AHAs). The use of AHAs in skin care products has attracted a great deal of attention in recent years. Details of the AHAs isolated from lanolin can be seen in

488-435: A secondary moisture reservoir within the skin. The barrier repair properties of lanolin have been reported to be superior to those produced by both petrolatum and glycerol. In a small clinical study conducted on volunteer subjects with terribly dry (xerotic) hands, lanolin was shown to be superior to petrolatum in reducing the signs and symptoms of dryness and scaling, cracks and abrasions, and pain and itch. In another study,

549-454: A single dose, or sometimes in two to four divided doses. There are concerns about the safety of such large doses. Low circulating vitamin D levels have been associated with lower total testosterone levels in males. Vitamin D supplementation could potentially improve total testosterone concentration, although more research is needed. A meta-analysis of 2007 concluded that daily intake of 1000 to 2000 IU/d of vitamin D 3 could reduce

610-399: A site for the endings of blood vessels and nerves. Many chromatophores are also stored in this layer, as are the bases of integumental structures such as hair , feathers , and glands . The hypodermis, otherwise known as the subcutaneous layer, is a layer beneath the skin. It invaginates into the dermis and is attached to the latter, immediately above it, by collagen and elastin fibers. It

671-411: A thin area called the nail matrix at an average of 1 mm per week. The lunula is the crescent-shape area at the base of the nail, lighter in color as it mixes with matrix cells. Only primates have nails. In other vertebrates, the keratinizing system at the terminus of each digit produces claws or hooves. The epidermis of vertebrates is surrounded by two kinds of coverings, which are produced by

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732-426: A wide range of cholecalciferol dosages, with LD 50 as high as 88 mg/kg or LD Lo as low as 2 mg/kg reported for dogs. Researchers have reported that the compound is less toxic to non-target species than earlier generations of anticoagulant rodenticides ( Warfarin and congeners ) or Bromethalin , and that relay toxicosis (poisoning by eating a poisoned animal) has not been documented. Nevertheless,

793-550: Is 0.025 μg , or 25 ng . Dietary reference intake values for vitamin D ( ergocalciferol , which is D 2 , or cholecalciferol, which is D 3 ), or both, have been established and recommendations vary depending on the country: Low levels of vitamin D3 are more commonly found in individuals living in northern latitudes or with other reasons for a lack of regular sun exposure, including being housebound, frail, elderly, or obese, having darker skin, and wearing clothes that cover most of

854-489: Is synthesized by the body during UVB radiation exposure. The three steps in the synthesis and activation of vitamin D 3 are regulated as follows: Cholecalciferol is produced industrially for use in vitamin supplements and to fortify foods . As a pharmaceutical drug it is called cholecalciferol ( USAN ) or colecalciferol ( INN , BAN ). It is produced by the ultraviolet irradiation of 7-dehydrocholesterol extracted from lanolin found in sheep's wool . Cholesterol

915-553: Is a credible case to consider when making vitamin D intake recommendations. Patients with severe vitamin D deficiency will require treatment with a loading dose ; its magnitude can be calculated based on the actual serum 25-hydroxy-vitamin D level and body weight. There are conflicting reports concerning the relative effectiveness of cholecalciferol (D 3 ) versus ergocalciferol (D 2 ), with some studies suggesting less efficacy of D 2 , and others showing no difference. There are differences in absorption, binding and inactivation of

976-404: Is a form of vitamin D which is naturally synthesized in skin and functions as a pro-hormone, being converted to calcitriol . This is important for maintaining calcium levels and promoting bone health and development. As a medication, cholecalciferol may be taken as a dietary supplement to prevent or to treat vitamin D deficiency. One gram is 40 000 000 ( 40 × 10 ) IU , equivalently 1 IU

1037-525: Is a heat insulator. The integumentary system has multiple roles in maintaining the body's equilibrium . All body systems work in an interconnected manner to maintain the internal conditions essential to the function of the body. The skin has an important job of protecting the body and acts as the body's first line of defense against infection, temperature change, and other challenges to homeostasis. Its main functions include: Small-bodied invertebrates of aquatic or continually moist habitats respire using

1098-536: Is a relatively common allergen and is often misunderstood as a wool allergy. However, allergy to a lanolin-containing product is difficult to pinpoint and often other products containing lanolin may be fine for use. Patch testing can be done if a lanolin allergy is suspected. It is frequently used in protective baby skin treatment and for sore nipples from breastfeeding but health authorities recommend alternative methods first, including nipple cleaning and improving baby positioning as well as expressing milk by hand. Lanolin

1159-485: Is also used as a lubricant for brass instrument tuning slides. Lanolin can also be restored to woollen garments to make them water and dirt repellent, such as for cloth diaper covers. Lanolin is also used in lip balm products such as Carmex . For some people, it can irritate the lips. Lanolin is sometimes used by people on continuous positive airway pressure therapy to reduce irritation with masks, particular nasal pillow masks that can often create sore spots in

1220-487: Is continuously removed during this washing process by centrifuge separators, which concentrate it into a waxlike substance melting at approximately 38 °C (100 °F). Lanolin and its many derivatives are used extensively in both the personal care (e.g., high value cosmetics, facial cosmetics, lip products) and health care sectors such as topical liniments. Lanolin is also found in lubricants, rust-preventive coatings, shoe polish, and other commercial products. Lanolin

1281-526: Is essentially composed of a type of cell known as adipocytes, which are specialized in accumulating and storing fats. These cells are grouped together in lobules separated by connective tissue. The hypodermis acts as an energy reserve. The fats contained in the adipocytes can be put back into circulation, via the venous route, during intense effort or when there is a lack of energy-providing substances, and are then transformed into energy. The hypodermis participates, passively at least, in thermoregulation since fat

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1342-409: Is extracted from wool grease and wool wax alcohols obtained from the cleaning of wool after shearing. The cholesterol undergoes a four-step process to make 7-dehydrocholesterol, the same compound that is produced in the skin of animals. The 7-dehydrocholesterol is then irradiated with ultraviolet light. Some unwanted isomers are formed during irradiation: these are removed by various techniques, leaving

1403-399: Is found in certain foods and can be taken as a dietary supplement . Cholecalciferol is synthesised in the skin following sunlight exposure. It is then converted in the liver to calcifediol (25-hydroxycholecalciferol D), which is further converted in the kidney to calcitriol (1,25-dihydroxycholecalciferol D). One of calcitriol’s most important functions is to promote calcium uptake by

1464-546: Is impossible from UV exposure; the skin reaches an equilibrium where the vitamin degrades as fast as it is created. Cholecalciferol can be produced in skin from the light emitted by the UV lamps in tanning beds , which produce ultraviolet primarily in the UVA spectrum, but typically produce 4% to 10% of the total UV emissions as UVB. Levels in blood are higher in frequent users of tanning salons. A 293 nanometer UVB light emitting diode (LED)

1525-458: Is not entirely clear how the two are related. Cholecalciferol is one of the five forms of vitamin D . Cholecalciferol is a secosteroid , that is, a steroid molecule with one ring open. By itself cholecalciferol is inactive. It is converted to its active form by two hydroxylations : the first in the liver, by CYP2R1 or CYP27A1 , to form 25-hydroxycholecalciferol ( calcifediol , 25-OH vitamin D 3 ). The second hydroxylation occurs mainly in

1586-400: Is one of the largest organs of the body. In humans, it accounts for about 12 to 15 percent of total body weight and covers 1.5 to 2 m of surface area. The skin (integument) is a composite organ, made up of at least two major layers of tissue: the epidermis and the dermis . The epidermis is the outermost layer, providing the initial barrier to the external environment. It is separated from

1647-506: Is regenerated from the stem cells found in the basal layer that develop into the corneum. The epidermis itself is devoid of blood supply and draws its nutrition from its underlying dermis. Its main functions are protection, absorption of nutrients, and homeostasis . In structure, it consists of a keratinized stratified squamous epithelium ; four types of cells: keratinocytes , melanocytes , Merkel cells , and Langerhans cells . The predominant cell keratinocyte , which produces keratin ,

1708-626: Is reported to have soothing properties but the lack of research leads to the previous recommendations being primary. Lanolin is used commercially in many industrial products ranging from rustproof coatings to lubricants . Some sailors use lanolin to create slippery surfaces on their propellers and stern gear to which barnacles cannot adhere. Commercial products (e.g. Lanocote) containing up to 85% lanolin are used to prevent corrosion in marine fasteners, especially when two different metals are in contact with each other and saltwater. The water-repellent properties make it valuable in many applications as

1769-457: Is the superficial layer that forms finger-like projections into the epidermis (dermal papillae), and consists of highly vascularized, loose connective tissue. The reticular layer is the deep layer of the dermis and consists of the dense irregular connective tissue. These layers serve to give elasticity to the integument, allowing stretching and conferring flexibility, while also resisting distortions, wrinkling, and sagging. The dermal layer provides

1830-526: Is used in various leather treatments, for example in some saddle soaps and in leather care products. In addition to general purity requirements, lanolin must meet official requirements for the permissible levels of pesticide residues. The Fifth Supplement of the United States Pharmacopoeia XXII published in 1992 was the first to specify limits for 34 named pesticides . A total limit of 40  ppm (i.e. 40 mg/kg) total pesticides

1891-663: The European Pharmacopoeia introduced pesticide residue limits into its lanolin monograph. This requirement, which is generally regarded as the new quality standard, extends the list of pesticides to 40 and imposes even lower concentration limits. Some very high-purity grades of lanolin surpass monograph requirements. New products obtained using complex purification techniques produce lanolin esters in their natural state, removing oxidative and environmental impurities resulting in white, odourless, hypoallergenic lanolin. These ultra-high-purity grades of lanolin are ideally suited to

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1952-410: The multilamellar vesicles formed by lanolin are identical to those formed by human stratum corneum lipids. The incorporation of bound water into the stratum corneum involves the formation of multilamellar vesicles. Skin bioengineering studies have shown the durational effect of the emollient (skin smoothing) action produced by lanolin is very significant and lasts for many hours. Lanolin applied to

2013-539: The nostrils . Lanolin is a popular additive to moustache wax , particularly 'extra-firm' varieties. Lanolin is used as a primary lubricating component in aerosol-based brass lubricants in the ammunition reloading process. Mixed warm 1:12 with highly concentrated ethanol (usually 99%), the ethanol acts as a carrier which evaporates quickly after application, leaving a fine film of lanolin behind to prevent brass seizing in resizing dies. Lanolin, when mixed with ingredients such as neatsfoot oil , beeswax and glycerol,

2074-821: The 200 or so different lanolin acids and the 100 or so different lanolin alcohols identified so far. Lanolin’s complex composition of long-chain esters, hydroxyesters, diesters, lanolin alcohols, and lanolin acids means in addition to its being a valuable product in its own right, it is also the starting point for the production of a whole spectrum of lanolin derivatives, which possess wide-ranging chemical and physical properties. The main derivatisation routes include hydrolysis , fractional solvent crystallisation , esterification , hydrogenation , alkoxylation and quaternisation . Lanolin derivatives obtained from these processes are used widely in both high-value cosmetics and skin treatment products. Hydrolysis of lanolin yields lanolin alcohols and lanolin acids. Lanolin alcohols are

2135-443: The body of the animal. Mainly it is the body's outer skin. The integumentary system includes skin , hair , scales , feathers , hooves , claws , and nails . It has a variety of additional functions: it may serve to maintain water balance, protect the deeper tissues, excrete wastes, and regulate body temperature , and is the attachment site for sensory receptors which detect pain, sensation, pressure, and temperature. The skin

2196-442: The body. Click on icon in lower right corner to open. Click on genes, proteins and metabolites below to link to respective articles. 7-Dehydrocholesterol is the precursor of cholecalciferol. Within the epidermal layer of skin, 7-dehydrocholesterol undergoes an electrocyclic reaction as a result of UVB light at wavelengths between 290 and 310 nm , with peak synthesis occurring at 293 nm . This results in

2257-404: The case of endocrine glands, transport their products. The dermis is the underlying connective tissue layer that supports the epidermis. It is composed of dense irregular connective tissue and areolar connective tissue such as a collagen with elastin arranged in a diffusely bundled and woven pattern. The dermis has two layers: the papillary dermis and the reticular layer. The papillary layer

2318-574: The control of these pests. The mechanism of high dose cholecalciferol is that it can produce " hypercalcemia , which results in systemic calcification of soft tissue, leading to kidney failure , cardiac abnormalities, hypertension , CNS depression, and GI upset. Signs generally develop within 18–36 h of ingestion and can include depression, loss of appetite , polyuria , and polydipsia ." High-dose cholecalciferol will tend to rapidly accumulate in adipose tissue yet release more slowly which will tend to delay time of death for several days from

2379-427: The dermis by the basement membrane ( basal lamina and reticular lamina ). The epidermis contains melanocytes and gives color to the skin. The deepest layer of the epidermis also contains nerve endings . Beneath this, the dermis comprises two sections, the papillary and reticular layers, and contains connective tissues , vessels, glands, follicles, hair roots , sensory nerve endings, and muscular tissue. Between

2440-464: The directive. Despite only being in force for a short period of time, this ruling did harm both to the lanolin industry and to the reputation of lanolin in general. The Cosmetics Directive ruling only applied to the presence of lanolin in cosmetic products; it did not apply to the many hundreds of its different uses in dermatological products designed for the treatment of compromised skin conditions. Modern analytical methods have revealed lanolin possesses

2501-434: The epidermis itself. In fish and aquatic amphibians , it is a thin mucus layer that is constantly being replaced. In terrestrial vertebrates, it is the stratum corneum (dead keratinized cells). The epidermis is, to some degree, glandular in all vertebrates, but more so in fish and amphibians . Multicellular epidermal glands penetrate the dermis, where they are surrounded by blood capillaries that provide nutrients and, in

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2562-451: The general healthy population and patients with dermatological disorders exaggerates the sensitising potential of lanolin by 5,000–6,000 times. The European Cosmetics Directive , introduced in July 1976, contained a stipulation that cosmetics which contained lanolin should be labelled to that effect. This ruling was challenged immediately, and in the early 1980s, it was overturned and removed from

2623-478: The incidence of colorectal cancer with minimal risk. Also a 2008 study published in Cancer Research has shown the addition of vitamin D 3 (along with calcium) to the diet of some mice fed a regimen similar in nutritional content to a new Western diet with 1000 IU cholecalciferol per day prevented colon cancer development. In humans, with 400 IU daily, there was no effect of cholecalciferol supplements on

2684-421: The integument and the deep body musculature there is a transitional subcutaneous zone made up of very loose connective and adipose tissue , the hypodermis . Substantial collagen bundles anchor the dermis to the hypodermis in a way that permits most areas of the skin to move freely over the deeper tissue layers. The epidermis is the strong, superficial layer that serves as the first line of protection against

2745-412: The intestines. Cholecalciferol is present in food such as fatty fish, beef liver, eggs, and cheese. In some countries, cholecalciferol is also added to products like plants, cow milk, fruit juice, yogurt, and margarine. Cholecalciferol can be taken orally as a dietary supplement to prevent vitamin D deficiency or as a medication to treat associated diseases, including rickets . It is also used in

2806-467: The kidney through the action of CYP27B1 to convert 25-OH vitamin D 3 into 1,25-dihydroxycholecalciferol ( calcitriol , 1,25-(OH) 2 vitamin D 3 ). All these metabolites are bound in blood to the vitamin D-binding protein . The action of calcitriol is mediated by the vitamin D receptor , a nuclear receptor which regulates the synthesis of hundreds of proteins and is present in virtually every cell in

2867-562: The management of familial hypophosphatemia , hypoparathyroidism that is causing low blood calcium , and Fanconi syndrome . Vitamin-D supplements may not be effective in people with severe kidney disease . Excessive doses in humans can result in vomiting, constipation, muscle weakness, and confusion. Other risks include kidney stones . Doses greater than 40 000   IU ( 1000 μg ) per day are generally required before high blood calcium occurs. Normal doses, 800–2000  IU per day, are safe in pregnancy . Cholecalciferol

2928-463: The opening of the vitamin precursor B-ring through a conrotatory pathway making previtamin D 3 (pre-cholecalciferol). In a process which is independent of UV light, the pre-cholecalciferol then undergoes a [1,7] antarafacial sigmatropic rearrangement and therein finally isomerizes to form vitamin D 3 . The active UVB wavelengths are little present in sunlight, and sufficient amounts of cholecalciferol can be produced with moderate exposure of

2989-425: The outer environment. The human epidermis is composed of stratified squamous epithelial cells , which further break down into four to five layers: the stratum corneum , stratum granulosum , stratum spinosum and stratum basale . Where the skin is thicker, such as in the palms and soles, there is an extra layer of skin between the stratum corneum and the stratum granulosum, called the stratum lucidum . The epidermis

3050-423: The outer layer (integument). This gas exchange system, where gases simply diffuse into and out of the interstitial fluid , is called integumentary exchange . Possible diseases and injuries to the human integumentary system include: Cholecalciferol Cholecalciferol , also known as vitamin D 3 or colecalciferol , is a type of vitamin D that is produced by the skin when exposed to UVB light ; it

3111-461: The risk of colorectal cancer. Supplements are not recommended for prevention of cancer as any effects of cholecalciferol are very small. Although correlations exist between low levels of blood serum cholecalciferol and higher rates of various cancers, multiple sclerosis , tuberculosis , heart disease, and diabetes, the consensus is that supplementing levels is not beneficial. It is thought that tuberculosis may result in lower levels. It, however,

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3172-499: The skin at 2 mg/cm has been shown to reduce roughness by about 35% after one hour and 50% after two hours, with the overall effect lasting for considerably more than eight hours. Lanolin is also known to form semiocclusive (breathable) films on the skin. When applied daily at around 4 mg/cm for five consecutive days, the positive moisturising effects of lanolin were detectable until 72 hours after final application. Lanolin may achieve some of its moisturising effects by forming

3233-411: The skin, depending on the strength of the sun. Time of day, season, latitude, and altitude affect the strength of the sun, and pollution, cloud cover or glass all reduce the amount of UVB exposure. Exposure of face, arms and legs, averaging 5–30  minutes twice per week, may be sufficient, but the darker the skin, and the weaker the sunlight, the more minutes of exposure are needed. Vitamin D overdose

3294-496: The skin. Supplements are recommended for these groups of people. The Institute of Medicine in 2010 recommended a maximum uptake of vitamin D of 4000 IU/d , finding that the dose for lowest observed adverse effect level is 40,000 IU daily for at least 12 weeks, and that there was a single case of toxicity above 10 000  IU after more than seven years of daily intake; this case of toxicity occurred in circumstances that have led other researchers to dispute whether it

3355-403: The table below. Crude lanolin constitutes about 5–25% of the weight of freshly shorn wool. The wool from one Merino sheep will produce about 250–300 ml of recoverable wool grease. Lanolin is extracted by washing the wool in hot water with a special wool scouring detergent to remove dirt, wool grease (crude lanolin), suint (sweat salts), and anything else stuck to the wool. The wool grease

3416-519: The time that high-dose bait is introduced. In New Zealand, possums have become a significant pest animal. For possum control, cholecalciferol has been used as the active ingredient in lethal baits. The LD 50 is 16.8 mg/kg, but only 9.8 mg/kg if calcium carbonate is added to the bait. Kidneys and heart are target organs. LD 50 of 4.4 mg/kg has been reported in rabbits, with lethality to almost all rabbits ingesting doses greater than 15 mg/kg. Toxicity has been reported across

3477-443: The treatment of dermatological disorders such as eczema and on open wounds. Lanolin attracted attention owing to a misunderstanding concerning its sensitising potential. A study carried out at New York University Hospital in the early 1950s had shown about 1% of patients with dermatological disorders were allergic to the lanolin being used at that time. By one estimate, this simple misunderstanding of failing to differentiate between

3538-430: The two forms, with evidence usually favoring cholecalciferol in raising levels in blood, although more research is needed. A much less common use of cholecalciferol therapy in rickets utilizes a single large dose and has been called stoss therapy. Treatment is given either orally or by intramuscular injection of 300 000  IU ( 7500 μg ) to 500 000  IU ( 12 500  μg  = 12.5 mg ), in

3599-650: Was first described in 1936. It is on the World Health Organization's List of Essential Medicines . In 2022, it was the 62nd most commonly prescribed medication in the United States, with more than 10   million prescriptions. Cholecalciferol is available as a generic medication . Cholecalciferol (vitamin D3) appears to stimulate the body's interferon type I signaling system that protects against bacteria and viruses, unlike vitamin D 2 . Cholecalciferol

3660-399: Was found to be 2.4 times more efficient in producing vitamin D3 than the sun in less than 1 ⁄ 60 the time. ( https://pubmed.ncbi.nlm.nih.gov/28904394/ ). Whether cholecalciferol and all forms of vitamin D are by definition " vitamins " can be disputed, since the definition of vitamins includes that the substance cannot be synthesized by the body and must be ingested. Cholecalciferol

3721-536: Was stipulated for lanolin of general use, with no individual limit greater than 10 ppm. A second monograph also introduced into the US Pharmacopoeia XXII in 1992 was entitled 'Modified Lanolin'. Lanolin conforming to this monograph is intended for use in more exacting applications, for example on open wounds. In this monograph, the limit of total pesticides was reduced to 3 ppm total pesticides, with no individual limit greater than 1 ppm. In 2000,

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