query: what does the skin produce in response to sunlight exposure

pos: Sun tanning Sun tanning Sun tanning or simply tanning is the process whereby skin color is darkened or tanned. It is most often a result of exposure to ultraviolet (UV) radiation from sunlight or from artificial sources, such as a tanning lamp found in indoor tanning beds. People who deliberately tan their skin by exposure to the sun engage in a passive recreational activity of sun bathing. Some people use chemical products which can produce a tanning effect without exposure to ultraviolet radiation, known as sunless tanning. Moderate exposure to the sun contributes to the production of melanin and vitamin D by

pos: Health effects of sunlight exposure benefits, and a number of public health organizations state that there needs to be a balance between the risks of having too much sunlight or too little. There is a general consensus that sunburn should always be avoided. UVB radiation with a wavelength of 290–315 nanometers penetrates uncovered skin and converts cutaneous 7-dehydrocholesterol to previtamin D, which in turn becomes vitamin D. UVB radiation does not penetrate glass, so exposure to sunshine indoors through a window does not produce vitamin D. Time of day, time of year, geographic latitude, ground altitude, cloud cover, smog, skin melanin content, and sunscreen are

pos: Light skin of a relatively light skinned person is able to produce between 10 - 20000 IU of vitamin D. Light-skinned people living in high sunlight environments are more susceptible to the harmful UV rays of sunlight because of the lack of melanin produced in the skin. The most common risk that comes with high exposure to sunlight is the increased risk of sunburns. This increased risk has come along with the cultural practice of sunbathing, which is popular among some human populations. This cultural practice to gain tanned skin if not regulated properly can lead to sunburn, especially among very lightly-skinned

pos: Cholecalciferol 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 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 uses of tanning salons.

pos: Human variability sunlight, has a darker color of skin tone. With evolution favors protection of folate (folic acid) from UV radiation, they have darker skin tone with more melanin to make sure child development is smooth and success. On the other hand, people who lived farther away from the equator have a lighter skin tone. They have lighter skin tone because they need more exposure and absorbance of sunlight to make sure the body produce enough vitamin D for survival. Blackfoot disease is a disease caused by environmental pollution and causes people to have black, charcoal-like skin in the lower limbs. This

pos: Sun tanning few weeks or months, much longer than the tan that is caused by oxidation of existing melanin, and is also actually protective against UV skin damage and sunburn, rather than simply cosmetic. Typically, it can provide a modest Sun Protection Factor (SPF) of 3, meaning that tanned skin would tolerate up to 3 times the UV exposure as pale skin. However, in order to cause true melanogenesis-tanning by means of UV exposure, some direct DNA photodamage must first be produced, and this requires UVB exposure (as present in natural sunlight, or sunlamps that produce UVB). The ultraviolet frequencies responsible for

pos: Sun tanning Sun tanning Sun tanning or simply tanning is the process whereby skin color is darkened or tanned. It is most often a result of exposure to ultraviolet (UV) radiation from sunlight or from artificial sources, such as a tanning lamp found in indoor tanning beds. People who deliberately tan their skin by exposure to the sun engage in a passive recreational activity of sun bathing. Some people use chemical products which can produce a tanning effect without exposure to ultraviolet radiation, known as sunless tanning. Moderate exposure to the sun contributes to the production of melanin and vitamin D by

pos: Light skin certain amount of vitamin D which penetrates the skin helps the body to absorb more calcium which is essential for building and maintaining bones, especially for developing embryos. Vitamin D production depends on exposure to sunlight. Humans living at latitudes far from the equator developed light skin in order to help absorb more vitamin D. People with light (type II) skin can produce previtamin D3 in their skin at rates 5–10 times faster than dark-skinned (type V) people. People living far from the equator were under evolutionary pressure to develop light skin, which allowed more penetration of UV radiation and

pos: Vitamin D deficiency in the diet, and decreased skin thickness which leads to further decreased absorption of vitamin D from sunlight. Although rickets and osteomalacia are now rare in Britain, osteomalacia outbreaks in some immigrant communities included women with seemingly adequate daylight outdoor exposure wearing typical Western clothing. Having darker skin and reduced exposure to sunshine did not produce rickets unless the diet deviated from a Western omnivore pattern characterized by high intakes of meat, fish, and eggs, and low intakes of high-extraction cereals. In sunny countries where rickets occurs among older toddlers and children, vitamin D deficiency has been attributed to low

pos: Health effects of sunlight exposure that vitamin D supplementation does not improve cardiovascular health or metabolism, so the link with vitamin D must be in part indirect. People who get more sun are generally healthier, and also have higher vitamin D levels. It has been found that ultraviolet radiation (even UVA) produces nitric oxide (NO) in the skin, and nitric oxide can lower blood pressure. High blood pressure increases the risk of stroke and heart disease. Although long-term exposure to ultraviolet contributes to non-melanoma skin cancers that are rarely fatal, it has been found in a Danish study that those who get these cancers were

pos: Human skin color practical purposes, such as exposure time for sun tanning, six skin types are distinguished following Fitzpatrick (1975), listed in order of decreasing lightness: The following list shows the six categories of the Fitzpatrick scale in relation to the 36 categories of the older von Luschan scale: Dark skin with large concentrations of melanin protects against ultraviolet light and skin cancers; light-skinned people have about a tenfold greater risk of dying from skin cancer, compared with dark-skinned persons, under equal sunlight exposure. Furthermore, UV-A rays from sunlight are believed to interact with folic acid in ways that may damage health. In

pos: Freckle Europeans. However, it can be found in all ethnicities. The formation of freckles is caused by exposure to sunlight. The exposure to UV-B radiation activates melanocytes to increase melanin production, which can cause freckles to become darker and more visible. This means that one may have never developed freckles before, but after extended exposure to sunlight, they may suddenly appear. Freckles are predominantly found on the face, although they may appear on any skin exposed to the sun, such as arms or shoulders. Heavily distributed concentrations of melanin may cause freckles to multiply and cover an entire area of skin,

pos: Health effects of sunlight exposure a time when large populations have migrated far from the climates for which their skin was genetically adapted. Health effects of sunlight exposure The ultraviolet radiation in sunlight has both positive and negative health effects, as it is both a principal source of vitamin D and a mutagen. A dietary supplement can supply vitamin D without this mutagenic effect. Vitamin D has a wide range of positive health effects, which include strengthening bones and possibly inhibiting the growth of some cancers. UV exposure also has positive effects for endorphin levels, and possibly for protection against multiple sclerosis. Visible sunlight to

pos: Naturism and direct experiences and a spontaneous approach to life. Sunlight has been shown to be beneficial in some skin conditions and enables the body to make vitamin D, but with the increased awareness of skin cancer, wearing of sunscreen is now part of the culture. Sun exposure prompts the body to produce nitric oxide that helps support the cardiovascular system and the feelgood brain-chemical serotonin. There are also documented psychological benefits of naturist activities including greater life satisfaction, more positive body image, and higher self-esteem. The World Naked Bike Ride (WNBR) is an international clothing-optional bike ride and exercise in

pos: Sunscreen PABA) tend to be withdrawn from the consumer market. Concerns have also been raised about potential vitamin D deficiency arising from prolonged use of sunscreen. Typical use of sunscreen does not usually result in vitamin D deficiency; however, extensive usage may. Sunscreen prevents ultraviolet light from reaching the skin, and even moderate protection can substantially reduce vitamin D synthesis. However, adequate amounts of vitamin D can be produced with moderate sun exposure to the face, arms and legs, averaging 5–30 minutes twice per week without sunscreen. (The darker the complexion, or the weaker the sunlight, the more minutes of exposure

pos: Health effects of sunlight exposure a direct UV signature mutation in 92% of all melanoma. UVC is the highest-energy, most-dangerous type of ultraviolet radiation, and causes adverse effects that can variously be mutagenic or carcinogenic. Despite the importance of the sun to vitamin D synthesis, it is prudent to limit the exposure of skin to UV radiation from sunlight and from tanning beds. According to the National Toxicology Program Report on Carcinogens from the US Department of Health and Human Services, broad-spectrum UV radiation is a carcinogen whose DNA damage is thought to contribute to most of the estimated 1.5 million skin cancers and the

pos: Health effects of sunlight exposure prevalent in the sunniest regions. Exposure to the ultraviolet-B radiation of sunlight appears to be most important and this may operate via vitamin D synthesis. Ultraviolet (UV) irradiation present in sunlight is an environmental human carcinogen. The toxic effects of UV from natural sunlight and therapeutic artificial lamps are a major concern for human health. The major acute effects of UV irradiation on normal human skin comprise sunburn inflammation erythema, tanning, and local or systemic immunosuppression. The most deadly form, malignant melanoma, is mostly caused by indirect DNA damage from UVA radiation. This can be seen from the absence of

pos: Vitamin D moderate sun exposure to the face, arms and legs, averaging 5–30 minutes twice per week, or approximately 25% of the time for minimal sunburn. The darker the skin, and the weaker the sunlight, the more minutes of exposure are needed. Vitamin D overdose is impossible from UV exposure; the skin reaches an equilibrium where the vitamin degrades as fast as it is created. Sunscreen absorbs or reflects ultraviolet light and prevents much of it from reaching the skin. Sunscreen with a sun protection factor (SPF) of 8 based on the UVB spectrum decreases vitamin D synthetic capacity by 95%, and

pos: Health effects of sunlight exposure among the factors that greatly affect UV intensity and vitamin D synthesis, making it difficult to provide general guidelines. It has been suggested by some researchers, for example, that adequate amounts of vitamin D can be produced with moderate sun exposure to the face, arms and legs, averaging 5–30 minutes twice per week without sunscreen. (The darker the complexion, or the weaker the sunlight, the more minutes of exposure are needed, approximating 25% of the time for minimal sunburn. Vitamin D overdose is impossible from UV exposure; the skin reaches an equilibrium where the vitamin degrades as fast as it

pos: Daylight saving time sunlight for outdoor exercise. It alters sunlight exposure; whether this is beneficial depends on one's location and daily schedule, as sunlight triggers vitamin D synthesis in the skin, but overexposure can lead to skin cancer. DST may help in depression by causing individuals to rise earlier, but some argue the reverse. The Retinitis Pigmentosa Foundation Fighting Blindness, chaired by blind sports magnate Gordon Gund, successfully lobbied in 1985 and 2005 for U.S. DST extensions. DST shifts are associated with higher rates of ischemic stroke in the first two days after the shift, though not in the week thereafter. Clock shifts

pos: Melanosome carry the vesicles containing the melanin to the center of the cell, which causes melanosomes to sequester the keratinocyte's nucleus, providing optimal protection from UV rays. These changes are responsible for tanning of human skin after exposure to UV light or sunlight. In many species of fish, amphibians, crustaceans, and reptiles, melanosomes can be highly mobile within the cell in response to hormonal (or sometimes neural) control, which leads to visible changes in colour that are used for behavioural signaling or photoprotection. Melanosomes found in certain fish species contain pigments that control the color of the fish's scales. Molecular motors,

pos: Health effects of sunlight exposure many climate zones, genetic selection has helped indigenous human populations adapt toward skin pigmentation levels that provide a healthy level of UV exposure. This largely explains the tendency toward darker-skinned populations in the sunniest tropical environments, and lighter skin tones in less-sunny regions and for those who most need vitamin D for rapid bone growth, specifically children and reproductive-age women. The map below illustrates the geographic distribution of skin color for native populations prior to 1940, based on von Luschan's chromatic scale. These long-term adaptations for optimal health can be confounded by patterns of food, clothing and shelter, especially at

pos: Vitamin D by polyuria, polydipsia, weakness, insomnia, nervousness, pruritus and ultimately renal failure. Furthermore, proteinuria, urinary casts, azotemia, and metastatic calcification (especially in the kidneys) may develop. Other symptoms of vitamin D toxicity include mental retardation in young children, abnormal bone growth and formation, diarrhea, irritability, weight loss, and severe depression. Vitamin D toxicity is treated by discontinuing vitamin D supplementation and restricting calcium intake. Kidney damage may be irreversible. Exposure to sunlight for extended periods of time does not normally cause vitamin D toxicity. The concentrations of vitamin D precursors produced in the skin reach an equilibrium, and any further vitamin

pos: Skin care detergents or mild liquid baby cleansers seems comparable or superior to water alone. Add from Sun protection is an important aspect of skin care. Though the sun is beneficial in order for the human body to get its daily dose of vitamin D, unprotected excessive sunlight can cause extreme damage to the skin. Ultraviolet (UVA and UVB) radiation in the sun's rays can cause sunburn in varying degrees, early ageing and increased risk of skin cancer. UV exposure can cause patches of uneven skin tone and dry out the skin. This can reduce the skin's elasticity and encourage sagging and

pos: Vitamin D a person's vitamin D is taken by mouth, as sun exposure in the population is variable and recommendations about the amount of sun exposure that is safe are uncertain in view of the skin cancer risk. Vitamin D from the diet or skin synthesis is biologically inactive; enzymatic conversion (hydroxylation) in the liver and kidney is required for activation. As vitamin D can be synthesized in adequate amounts by most mammals exposed to sufficient sunlight, it is not an essential dietary factor, and so not technically a vitamin. Instead it could be considered a hormone, with activation of the vitamin

pos: Edible mushroom per 100 grams for several nutrients increase appreciably, especially for dietary minerals (table for boiled mushrooms). The content of vitamin D is absent or low unless mushrooms are exposed to sunlight or purposely treated with artificial ultraviolet light ("see" below). Mushrooms exposed to ultraviolet (UV) light produce vitamin D before or after harvest by converting ergosterol, a chemical found in large concentrations in mushrooms, to vitamin D. This is similar to the reaction in humans, where vitamin D is synthesized after exposure to sunlight. Testing showed an hour of UV light exposure before harvesting made a serving of mushrooms contain

pos: Human skin color dates to at about 1.2 million years ago, under conditions of a megadrought that drove early humans into arid, open landscapes. Such conditions likely caused excess UV-B radiation. This favored the emergence of skin pigmentation in order to protect from folate depletion due to the increased exposure to sunlight. A theory that the pigmentation helped counter xeric stress by increasing the epidermal permeability barrier has been disproved. With the evolution of hairless skin, abundant sweat glands, and skin rich in melanin, early humans could walk, run, and forage for food for long periods of time under the hot sun without

pos: Veganism mushrooms. Most vegan diets contain little or no vitamin D without fortified food. People with little sun exposure may need supplements. The extent to which sun exposure is sufficient depends on the season, time of day, cloud and smog cover, skin melanin content, and whether sunscreen is worn. According to the National Institutes of Health, most people can obtain and store sufficient vitamin D from sunlight in the spring, summer, and fall, even in the far north. They report that some researchers recommend 5–30 minutes of sun exposure without sunscreen between 10 am and 3 pm, at least twice a

pos: Melanism for the synthesis of vitamin D in skin, so lighter colored skin - less melanin - is an adaptation related to the prehistoric movement of humans away from equatorial regions, as there is less exposure to sunlight at higher latitudes. People from parts of Africa, South Asia, Southeast Asia, and Australia have very dark skin, but this is not melanism. This rare genetic disorder is characterized by the development of macules with Hyperpigmentation on the lips and oral mucosa (melanosis), as well as benign polyps in the gastrointestinal tract. The term "melanism" has been used on Usenet, internet forums and

pos: Vitamin D deficiency D levels falling within this normal range prevent clinical manifestations of vitamin D insufficiency as well as vitamin D toxicity from taking in too much vitamin D. Vitamin D deficiency can be asymptomatic, but may also cause several problems including: Vitamin D deficiencies are often caused by decreased exposure of the skin to sunlight. People with a darker pigment of skin or increased amounts of melanin in their skin may have decreased production of Vitamin D. Melanin absorbs ultraviolet B radiation from the sun and reduces vitamin D production. Sunscreen can also reduce vitamin D production. Medications may speed up

pos: Health effects of sunlight exposure makes taking oral vitamin D ineffective are able, through exposure to an ultraviolet lamp that emits UV-B radiation, to achieve a 25 (OH) D blood level. Three benefits of UV exposure are production of vitamin D, improvement in mood, and increased energy. UVB induces production of vitamin D in the skin at rates of up to 1,000 IUs per minute. This vitamin helps to regulate calcium metabolism (vital for the nervous system and bone health), immunity, cell proliferation, insulin secretion, and blood pressure. In third-world countries, foods fortified with vitamin D are "practically nonexistent." Most people in the world depend

pos: Rickets exposure due to the increased risk of skin cancer associated with sun exposure. Endogenous production with full body exposure to sunlight is approximately 250 µg (10,000 IU) per day. According to the American Academy of Pediatrics (AAP), all infants, including those who are exclusively breast-fed, may need vitamin D supplementation until they start drinking at least of vitamin D-fortified milk or formula a day. In developed countries, rickets is a rare disease (incidence of less than 1 in 200,000). Recently, cases of rickets have been reported among children who are not fed enough vitamin D. In 2013/2014 there were fewer

neg: Health effects of sunlight exposure D. One minimal erythemal dose of sunlight UV radiation provides the equivalent of about 20,000 IU of vitamin D2, taken as an oral supplement. If an adult's arms and legs are exposed to a half minimal erythemal UV radiation, it is the same as taking 3,000 IU of vitamin D3 through an oral supplement. This exposure of 10–15 minutes, on a frequency of two to three times per week will cause the adult's skin to produce enough vitamin D. It is not necessary to expose the face to the UV, as facial skin provides little vitamin D3. Individuals whose metabolism

neg: Sun tanning on the body, instead it uses a colorless chemical which reacts with proteins in the top layer of the skin, resulting in a brown color. Sun tanning Sun tanning or simply tanning is the process whereby skin color is darkened or tanned. It is most often a result of exposure to ultraviolet (UV) radiation from sunlight or from artificial sources, such as a tanning lamp found in indoor tanning beds. People who deliberately tan their skin by exposure to the sun engage in a passive recreational activity of sun bathing. Some people use chemical products which can produce a tanning

neg: Sunburn recommend the following measures to prevent excessive UV exposure and skin cancer: The strength of sunlight is published in many locations as a UV Index. Sunlight is generally strongest when the sun is close to the highest point in the sky. Due to time zones and daylight saving time, this is not necessarily at 12 noon, but often one to two hours later. Seeking shade including using umbrellas and canopies can reduce the amount of UV exposure, but does not block all UV rays. The WHO recommends following the shadow rule: "Watch your shadow – Short shadow, seek shade!" Commercial

neg: Delayed sleep phase disorder comes from lack of exposure to sunlight, anyone who does not get enough sunlight exposure during daylight hours (about 20 to 30 minutes three times a week, depending on skin tone, latitude, and the time of year) could be at risk, without adequate dietary sources or supplements. DSPD is genetically linked to attention deficit hyperactivity disorder by findings of polymorphism in genes in common between those apparently involved in ADHD and those involved in the circadian rhythm and a high proportion of DSPD among those with ADHD. Persons with obsessive-compulsive disorder are also diagnosed with DSPD at a much higher

neg: Sunless tanning them contain parabens. Parabens are preservatives that can affect the endocrine system. Sunless tanning Sunless tanning, also known as UV filled tanning, self tanning, spray tanning (when applied topically), or fake tanning, refers to the application of chemicals to the skin to produce an effect similar in appearance to a suntan. The popularity of sunless tanning has risen since the 1960s after health authorities confirmed links between UV exposure (from sunlight or tanning beds) and the incidence of skin cancer. Since sunscreen absorbs ultraviolet light and prevents it from reaching the skin, it will prevent tanning. It has been reported

neg: Sunless tanning Sunless tanning Sunless tanning, also known as UV filled tanning, self tanning, spray tanning (when applied topically), or fake tanning, refers to the application of chemicals to the skin to produce an effect similar in appearance to a suntan. The popularity of sunless tanning has risen since the 1960s after health authorities confirmed links between UV exposure (from sunlight or tanning beds) and the incidence of skin cancer. Since sunscreen absorbs ultraviolet light and prevents it from reaching the skin, it will prevent tanning. It has been reported that sunscreen with a sun protection factor (SPF) of 8 based on

neg: Health effects of sunlight exposure robust circadian rhythms, and reduced risk of seasonal affective disorder. Long-term sunlight exposure is known to be associated with the development of skin cancer, skin aging, immune suppression, and eye diseases such as cataracts and macular degeneration. Effects of UV-radiation at high latitudes, where snow stays on the ground into early summer and the sun then remains at a low position even at its zenith, have been reviewed by Meyer-Rochow. Short-term overexposure is the cause of sunburn, snow blindness, and solar retinopathy. UV rays, and therefore sunlight and sunlamps, are the only listed carcinogens that are known to have health

neg: Fluorescent lamps and health Protection Agency of the United Kingdom has conducted research concluding that exposure to open (single envelope) compact fluorescent lamps (CFLs) for over 1 hour per day at a distance of less than 30 cm can exceed guideline levels as recommended by the International Commission on Non-Ionizing Radiation Protection (ICNIRP). Not all open CFLs produce significant UV emissions. However, close proximity to bare skin can result in exposure levels similar to direct sunlight. The Health Protection Agency of the United Kingdom recommend that in situations requiring close proximity to the light source, open (single envelope) CFLs be replaced with encapsulated (double

neg: Health effects of sunlight exposure over-exposure causes the pain and itching of sunburn, which in extreme cases can produce more-severe effects like blistering. Several countries (such as Australia) provide public forecasts of UV irradiation in the form of the UV Index. The index can be used as a guide to the public of dangers from over-exposure to sunlight, especially at noon, when direct sunlight is at its most intense. Light to the eyes, primarily blue-wavelength light, is important for the entrainment and maintenance of robust circadian rhythms. Exposure to sunlight in the morning is particularly effective; it leads to earlier melatonin onset in the evening

neg: ILC2 viruses and that is why ILC2s are abundant in tissues of skin, lungs, livers and gut. ILC2s play a variety of roles in allergy. Primarily, they provide a source of the type 2 cytokines that orchestrate the allergic immune response. They produce a profile of signals in response to pro-allergenic cytokines IL-25 and IL-33 that is similar to those produced in response to helminthic infection. Their contribution to this signaling appears to be comparable to that of T cells. In response to allergen exposure in the lungs, ILC2s produce IL-13, a necessary cytokine in the pathogenesis of allergic reactions. This

neg: Human skin color that such major changes in pigmentation may have happened in as little as 100 generations (≈2,500 years) through selective sweeps. Natural skin color can also darken as a result of tanning due to exposure to sunlight. The leading theory is that skin color adapts to intense sunlight irradiation to provide partial protection against the ultraviolet fraction that produces damage and thus mutations in the DNA of the skin cells. In addition, it has been observed that adult human females on average are significantly lighter in skin pigmentation than males. Females need more calcium during pregnancy and lactation. The body synthesizes

neg: Health effects of sunlight exposure peaks of the 11-year solar cycle, possibly because of UV-related folate deficiency during gestation. According to a 2007 study submitted by the University of Ottawa to the US Department of Health and Human Services, there is not enough information to determine a safe level of sun exposure that imposes minimal risk of skin cancer. In addition, there is not yet conclusive evidence on which components of ultraviolet radiation (UVA, UVB, UVC) are actually carcinogenic. UVC is almost completely absorbed by the atmosphere and does not reach the surface in any appreciable quantity. As a result, only the broad-spectrum combination (UVA,

neg: Polymorphous light eruption recurrent non scarring eczematous lesions triggered by sun exposure. Danish physician Carl Rasch first described the "eczema-like polymorphic light eruption" in 1900, following his interest in the effect of sunlight on the skin. He has since been credited with coining the term "polymorphic light eruption". Polymorphous light eruption Polymorphous light eruption (PLE), sometimes also called polymorphic light eruption (PMLE), is a non-life-threatening and potentially distressing skin condition that is triggered by sunlight and artificial UV exposure in a genetically susceptible person, particularly in temperate climates during the spring and early summer. Due to its many clinical appearances, it is named

neg: Mexicans of European descent given category, additional phenotypical traits besides the respondents’ skin color were considered, such as the presence of blond hair in the case of individuals that were to be classified in the "White" category, because "unlike skin color, hair color does not darken with exposure to sunlight." It is indeed claimed within the study that out of the three color categories used, the percentages obtained for the "White" one through the three waves of interviews were the most consistent. According to the results of the study, the average percentage of Mexicans who were classified as "White" per the presence of blond

neg: Trichobilharzia regenti (IL-1β, IL-6 and IL-12p40) and anti-inflammatory (IL-10) cytokines in a skin of mice infected for the first time. Lymphocytes from their skin draining lymph nodes exhibit mixed Th1/Th2 polarization after exposure to parasite antigens. On the contrary, anti-inflammatory IL-4 and IL-10 dominate in mice infected repeatedly which also secrete large amounts of histamine from mast cells. Lymphocytes from their skin draining lymph nodes produce IL-4 and IL-5 after stimulation with parasite antigens which shows Th2 polarization of host immune response. In a spinal cord, strong cellular immune response consisting of granulocytes, plasma cells, macrophages, and T-cells develops in immunocompetent mice

neg: Brown effects. Natural skin color can darken as a result of tanning due to exposure to sunlight. The leading theory is that skin color adapts to intense sunlight irradiation to provide partial protection against the ultraviolet fraction that produces damage and thus mutations in the DNA of the skin cells. There is a correlation between the geographic distribution of ultraviolet radiation (UVR) and the distribution of indigenous skin pigmentation around the world. Darker-skinned populations are found in the regions with the most ultraviolet, closer to the equator, while lighter skinned populations live closer to the poles, with less UVR, though immigration

neg: Ammonium lactate Ammonium lactate Ammonium lactate is a compound with formula NH(CH(OH)COO). It is the ammonium salt of lactic acid. It has mild anti-bacterial properties. It has E number "E328" and is the active ingredient of the skin lotions Amlactin and Lac-Hydrin. Ammonium lactate is a mix of lactic acid and ammonium hydroxide. It is used as a skin moisturizer lotion to treat dry, scaly, itchy skin. Those who are using it should avoid exposure to sunlight or artificial UV rays, such as sunlamps or tanning beds. Ammonium lactate makes skin more sensitive to sunlight. Skin is more likely to sunburn. Use

neg: Nick Knight (Forever Knight) or natural death, but can be killed by exposure to sunlight, having a wooden stake driven through his heart, fire, or decapitation. Knight appears human in normal circumstances, although he rarely perspires – and when he does, he does not perspire sweat, but rather blood – and his skin is cold to the touch. Knight will reveal his vampire traits when threatened, or when becoming aggressive. This is known as "vamping out" by the fans of the series, but it is never referred as such during the series. When taking a vampire aspect, Knight's eyes turn yellow, and bares the

neg: Agalychnis lemur this fungus. Scientist are attributing tree frog's ability to withstand the deadly fungus to their unusual skin which allows the frogs to bask in the hot sunlight boosting their temperatures adequately enough to kill off the fungus. While typically a frog's long exposure to sunlight would dry out its skin, this species of tree frogs in Costa Rica thrive under the high temperature conditions. Scientists believe these tree frogs are able to thrive under these harsh conditions, which normally negatively affect frogs because of their skins ability to reflect the sunlight, regulating their core temperature, yet maintaining enough heat to

neg: Ripeness in viticulture to build up in the skins and pulp. Additionally the concentration of tannins in the grape increases in several areas of the grape including the skin, seeds and stem. Early in the ripening process these tannins are very bitter and "green". Exposure to the warmth and sunlight during the ripening period ushers in chemical changes to the tannins that when processed into wine makes the tannins feel softer in the mouth. What constitutes "ripeness" will vary according to what style of wine is being produced as well as the particular views of winemakers and viticulturists on what optimal ripeness is.

neg: Ammonium lactate sunblock and wear clothes when exposed to sunlight. Ammonium lactate Ammonium lactate is a compound with formula NH(CH(OH)COO). It is the ammonium salt of lactic acid. It has mild anti-bacterial properties. It has E number "E328" and is the active ingredient of the skin lotions Amlactin and Lac-Hydrin. Ammonium lactate is a mix of lactic acid and ammonium hydroxide. It is used as a skin moisturizer lotion to treat dry, scaly, itchy skin. Those who are using it should avoid exposure to sunlight or artificial UV rays, such as sunlamps or tanning beds. Ammonium lactate makes skin more sensitive to

neg: The Sunlight League the idea behind it was to stimulate the nudst movement. The League was dissolved in 1940, following the death of Saleeby. In modern times, there is concern about the risk of skin cancer from excessive exposure to sunlight. However, The Sunlight League was recalled in a 1996 article in The Independent newspaper, which argued that fear of sunlight may have gone too far. Cora Wilding founded a Sunlight League in New Zealand in 1930. It is not known whether this was connected with the League in England. The Sunlight League The Sunlight League was founded in England in 1924 by

neg: Merkel-cell carcinoma what other steps or co-factors were required for MCC-type cancers to develop. At least 20% of MCC tumors are not infected with MCV, suggesting that MCC may have other causes, especially sunlight or ultraviolet light as in a tanning beds. MCC can also occur together with other sun exposure-related skin cancers that are not infected with MCV (i.e. basal cell carcinoma, squamous cell carcinoma, melanoma). Ultraviolet radiation such as in sun exposure increases the risk in MCC development, consistent with the fact that MCCs occur more commonly in sun-exposed areas. The incidence of MCC is increased in conditions with defective

neg: Blacklight turn can damage DNA and result in a risk of melanoma. The weak output of black lights, however, is not considered sufficient to cause DNA damage or cellular mutations in the way that direct summer sunlight can, although there are reports that overexposure to the type of UV radiation used for creating artificial suntans on sunbeds can cause DNA damage, photoaging (damage to the skin from prolonged exposure to sunlight), toughening of the skin, suppression of the immune system, cataract formation and skin cancer. Ultraviolet radiation is invisible to the human eye, but illuminating certain materials with UV radiation causes

neg: Allergic response produce histamines. These histamines will act on different areas of the body (eyes, throat, nose, gastrointestinal tract, skin or lungs) to produce symptoms of an allergic reaction. The allergic response is not limited to a certain amount of exposure. If the body is exposed to the allergen multiple times the immune system will react every time the allergen is present. The reason why people get allergies is not known. The allergens are not passed down through generations. It is believed if parents have allergies the child is more likely to be allergic to the same allergens. Some common symptoms include

neg: Seasonal affective disorder results are evident when continued throughout several weeks. Most studies have found it effective without use year round but rather as a seasonal treatment lasting for several weeks until frequent light exposure is naturally obtained. Light therapy can also consist of exposure to sunlight, either by spending more time outside or using a computer-controlled heliostat to reflect sunlight into the windows of a home or office. Although light therapy is the leading treatment for seasonal affective disorder, prolonged direct sunlight or artificial lights that don't block the ultraviolet range should be avoided due to the threat of skin cancer. SSRI

neg: Sulfur hexafluoride as well as being more reliable in long-term operation because of its controlled operating environment. Exposure to an arc chemically breaks down though most of the decomposition products tend to quickly re-form , a process termed "self-healing". Arcing or corona can produce disulfur decafluoride (), a highly toxic gas, with toxicity similar to phosgene. was considered a potential chemical warfare agent in World War II because it does not produce lacrimation or skin irritation, thus providing little warning of exposure. Alternatives include fluoroketone. is used to provide a tamponade or plug of a retinal hole in retinal detachment repair operations

neg: Contact dermatitis areas of skin which are left uncovered by clothing, and it can be soundly defeated by avoiding exposure to sunlight. The mechanism of action varies from toxin to toxin, but is usually due to the production of a photoproduct. Toxins which are associated with PCD include the psoralens. Psoralens are in fact used therapeutically for the treatment of psoriasis, eczema, and vitiligo. Photocontact dermatitis is another condition in which the distinction between forms of contact dermatitis is not clear-cut. Immunological mechanisms can also play a part, causing a response similar to ACD. Since contact dermatitis relies on an irritant or

neg: Favre–Racouchot syndrome Favre–Racouchot syndrome Favre–Racouchot syndrome (also known as "Favre–Racouchot disease", and "nodular cutaneous elastosis with cysts and comedones") is a solar elastotic disorder consisting of multiple open comedones that occurs in skin damaged by sunlight, especially under and lateral of the eyes. The comedones are widened openings for hair follicles and sebaceous glands filled with material. Chronic exposure to ultraviolet light can result in skin thickening as well as elastic destruction of the skin. At least in one instance, the occupational exposure to the UVA light of the sun (UVB is blocked by many car windows) resulted in skin destruction on

neg: Melanizing agents should be undertaken for many weeks to obtain observable results. Longer exposure to sunlight might cause blistering of skin, so the therapy should be undertaken in the direct supervision of a physician. It is done in alternate days. After 2 hours of taking the oral dose of 20 mg/day of a psoralen, skin is exposed to sunlight. Eyes, ears and other normally pigmented areas should be protected while spending time in the sun. Melanizing agents Melanizing agents are drugs that increase sensitivity to solar radiation and promote re-pigmentation of de-pigmented areas of skin. Furocoumarins stimulate melanocytes and induce their proliferation

neg: Sexual selection in humans had light skin that was covered by dark hair. Additionally, our closest extant relative, the chimpanzee, has light skin covered by thick body hair. Over time human hair disappeared to allow better heat dissipation through sweating and the skin tone grew darker to increase the epidermal permeability barrier and protect from folate depletion due to the increased exposure to sunlight. When humans started to migrate away from the tropics, there was less-intense sunlight, partly due to clothing to protect against cold weather. Under these conditions there was less photodestruction of folate, and so the evolutionary pressure stopping lighter-skinned gene variants

neg: Squamous cell skin cancer case of cSCC people are at high risk of developing further cases. SCC of the skin begins as a small nodule and as it enlarges the center becomes necrotic and sloughs and the nodule turns into an ulcer. Squamous cell carcinoma is the second-most common cancer of the skin (after basal-cell carcinoma but more common than melanoma). It usually occurs in areas exposed to the sun. Sunlight exposure and immunosuppression are risk factors for SCC of the skin, with chronic sun exposure being the strongest environmental risk factor. There is a risk of metastasis starting more than 10 years after

neg: Gunther disease long-wave ultraviolet light causes the affected skin to thicken and produce vesicles that are prone to rupture and infection; these secondary infections, along with bone resorption, can lead to disfigurement of the sun-exposed face and extremities. Enzyme dysfunction prevents the normal production of heme and hemolytic anemia is another common symptom, though a lack of hemolysis in this disease is possible. Porphyrins additionally accumulate in the bone and teeth, resulting in erythrodontia. When unexpected attacks occur, abdominal pain, as well as vomiting and constipation commonly follow the attacks. Exposure to the sunlight can cause discomfort and result in blistering, consciousness

neg: Sunburn tanning beds, and do not recommend suntans as a form of sun protection. The differential diagnosis of sunburn includes other skin pathology induced by UV radiation including photoallergic reactions, phototoxic reactions to topical or systemic medications, and other dermatologic disorders that are aggravated by exposure to sunlight. Considerations for diagnosis include duration and intensity of UV exposure, use of topical or systemic medications, history of dermatologic disease, and nutritional status. The most effective way to prevent sunburn is to reduce the amount of UV radiation reaching the skin. The World Health Organization, American Academy of Dermatology, and Skin Cancer Foundation

neg: Psoriasis Data are inconclusive with respect to non-melanoma skin cancer risk, but support the idea that the therapy is associated with an increased risk of benign forms of sun-induced skin damage such as, but not limited to, actinic elastosis or liver spots. Dead Sea balneotherapy is also effective for psoriatic arthritis. Phototherapy in the form of sunlight has long been used for psoriasis. UVB Wavelengths of 311–313 nanometers are most effective, and special lamps have been developed for this application. The exposure time should be controlled to avoid over exposure and burning of the skin. The UVB lamps should have a

neg: Ichthyosis are used for some conditions. Exposure to sunlight may improve or worsen the condition. In some cases, excess dead skin sloughs off much better from wet tanned skin after bathing or a swim, although the dry skin might be preferable to the damaging effects of sun exposure. There can be ocular manifestations of ichthyosis, such as corneal and ocular surface diseases. Vascularizing keratitis, which is more commonly found in congenital keratitis-ichythosis-deafness (KID), may worsen with isotretinoin therapy. Ichthyosis or ichthyosis-like disorders exist for several types of animals, including cattle, chickens, llamas, mice and dogs. Ichthyosis of varying severity is well

neg: Night photography essentially a dark body in direct sunlight, photographing its surface needs an exposure comparable to what a photographer would use for ordinary, mid-brightness surfaces (buildings, trees, faces, etc.) with an overcast sky. The sunlight reflected from the full Moon onto Earth is about 1/250,000 of the brightness of direct sunlight in daytime. Since , full-moon photography requires 18 stops more exposure than sunlight photography, for which the sunny 16 rule is a commonly used guideline. Imagine a directly sunlit exposure of 1/100 second at ISO 100 and f/16 (the baseline of sunny 16). Adding 18 stops to convert from the

neg: Physical hazard source of ultraviolet (UV) rays which are the form of non-ionizing radiation. UV rays directly from sunlight and indirect sun exposure, such as light reflected by snow and light-shaded sand can penetrate worker’s uncovered skin. Long time, continuous exposure to ultraviolet radiation results in suppression of the immune system, eye damage, skin aging, and skin cancer. Some non-solar sources of UV radiation, for example, projection lamps, the curing of paints and inks, equipment disinfectant used in hospitals, fluorescent tubes, sunlamps, and welding arcs, can also cause adverse health effects in other workers. Personal protective equipment, engineering, and administrative controls such

neg: Merkel-cell carcinoma microscopy, immunohistochemistry (IHC) is also generally required to differentiate MCC from other morphologically similar tumors such as small cell lung cancer, the small cell variant of melanoma, various cutaneous leukemic/lymphoid neoplasms, and Ewing's sarcoma. Similarly, most experts recommend longitudinal imaging of the chest, typically a CT scan, to rule out that the possibility that the skin lesion is a skin metastasis of an underlying small cell carcinoma of the lung. Sunlight exposure is thought to be one of the causes of Merkel cell carcinoma (MCC). As a result, it is important to prevent the skin from excessive sun exposure. For

neg: Mutagenesis breakages and rearrangements. Some crosslinkers such as cyclophosphamide, mitomycin C and cisplatin are used as anticancer chemotherapeutic because of their high degree of toxicity to proliferating cells. UV radiation promotes the formation of a cyclobutyl ring between adjacent thymines, resulting in the formation of pyrimidine dimers. In human skin cells, thousands of dimers may be formed in a day due to normal exposure to sunlight. DNA polymerase η may help bypass these lesions in an error-free manner; however, individuals with defective DNA repair function, such as sufferers of xeroderma pigmentosum, are sensitive to sunlight and may be prone to skin

neg: Sunburn Skin type determines the ease of sunburn. In general, people with lighter skin tone and limited capacity to develop a tan after UV radiation exposure have a greater risk of sunburn. The Fitzpatrick's Skin phototypes classification describes the normal variations of skin responses to UV radiation. Persons with type I skin have the greatest capacity to sunburn and type VI have the least capacity to burn. However, all skin types can develop sunburn. Fitzpatrick's skin phototypes: Age also affects how skin reacts to sun. Children younger than six and adults older than sixty are more sensitive to sunlight. There are

neg: Hereditary coproporphyria of abdominal pain, nausea, vomiting, diarrhea, tachycardia, hypertension and seizures, as well as the cutaneous findings seen in porphyria cutanea tarda (PCT), namely increased skin fragility, bullous lesions after exposure to sunlight and increased scarring. Individuals with HCP may be asymptomatic in the absence of triggering factors. Common triggers include certain drugs, alcohol, hormonal changes, and dietary changes. Sunlight and other ultraviolet light can trigger the skin manifestations. Homozygous individuals for "CPOX" mutations can present with these findings at an earlier age than heterozygotes. HCP is caused by mutations in "CPOX", which codes for the enzyme coproporphyrinogen oxidase. This enzyme

neg: Turquoise oil is absorbed and the turquoise therefore does not "rely" on this impermanent treatment for its beauty. All other factors being equal, untreated turquoise will always command a higher price. Bonded and "reconstituted" material is worth considerably less. Being a phosphate mineral, turquoise is inherently fragile and sensitive to solvents; perfume and other cosmetics will attack the finish and may alter the colour of turquoise gems, as will skin oils, as will most commercial jewellery cleaning fluids. Prolonged exposure to direct sunlight may also discolour or dehydrate turquoise. Care should therefore be taken when wearing such jewels: cosmetics, including sunscreen

neg: Desensitization (psychology) the possibility of affecting the way we perceive others and interpret their actions. It is hypothesized that initial exposure to violence in the media may produce a number of aversive responses such as increased heart rate, fear, discomfort, perspiration and disgust. However, prolonged and repeated exposure to violence in the media may reduce or habituate the initial psychological impact until violent images do not elicit these negative responses. Eventually the observer may become emotionally and cognitively desensitized to media violence. In one experiment, participants who played violent video games showed lower heart rate and galvanic skin response readings, which the

neg: Photosensitivity amiodarone, and sulfonamides. Some dietary supplements, such as St. John's Wort, include photosensitivity as a possible side effect. Particular conditions lead to increased light sensitivity. Patients with systemic lupus erythematosus experience skin symptoms after sunlight exposure; some types of porphyria are aggravated by sunlight. A rare hereditary condition xeroderma pigmentosum (a defect in DNA repair) is thought to increase the risk of UV-light-exposure-related cancer by increasing photosensitivity. Photosensitivity occurs in multiple species including sheep, bovine, and horses. They are classified as primary if an ingested plant contains a photosensitive substance, like hypericin in St John's wort poisoning and ingestion of

neg: Photodermatitis Photodermatitis Photodermatitis, sometimes referred to as sun poisoning or photoallergy, is a form of allergic contact dermatitis in which the allergen must be activated by light to sensitize the allergic response, and to cause a rash or other systemic effects on subsequent exposure. The second and subsequent exposures produce photoallergic skin conditions which are often eczematous. It is distinct from sunburn. Photodermatitis may result in swelling, difficulty breathing, a burning sensation, a red itchy rash sometimes resembling small blisters, and peeling of the skin. Nausea may also occur. There may also be blotches where the itching may persist for long

neg: Illithid of hearing is slightly poorer than a human's; they have difficulty distinguishing between several sounds mixed together, yet they are good at discerning from what direction sounds came from. Their skin is purplish blue to gray-green and covered in mucus, and is very sensitive to sunlight. They loathe sunlight, though it does not actually harm them. One of their most feared powers is the dreaded "Mind Blast", where the illithid emits a cone-shaped psionic shock wave with its mind in order to incapacitate any creature for a short amount of time. Illithids also have other psionic powers, generally telepathic in

neg: Physical hazard Personal protective equipment such as hard hats, hoods, sleeves, rubber or insulating gloves and insulating clothing can be useful to reduce any electrical accidents. Sunlight is the most commonly known physical hazard which affects the people who work outside. Outdoor workers get highest sunlight exposure during high-intensity hours between 10:00 a.m. to 4:00 p.m. and during the summertime. The risk of getting sunburned is more throughout these times. Some commonly used medicines such as nonsteroidal anti-inflammatory drugs (NSAIDS), antihistamines, tetracycline, thiazides, sulfa antibiotics, and diuretics increase sensitivity to sunlight and resulting in skin rashes and sunburn. Moreover, sunlight is a

neg: Polymorphous light eruption rash of lupus is inclined to be more persistent. PLE does not increase the risk of lupus. Other similar appearing conditions are solar urticaria, which has a shorter duration, the eczema-like condition, photosensitive dermatitis, and photosensitivity drug reaction. Prickly heat, which is caused by warm weather or heat is not the same as PLE. Photosensitivity is also found in some of the porphyrias. Nearly all cases of porphyria cutanea tarda exhibit blister formation on the skin within 2–4 days of light exposure. Variegate porphyria and hereditary coproporphyria can also exhibit symptoms of light-induced blisters. Sunlight has been documented to trigger

neg: Carcinogen cancer incidence. Higher-energy radiation, including ultraviolet radiation (present in sunlight), x-rays, and gamma radiation, generally "is" carcinogenic, if received in sufficient doses. For most people, ultraviolet radiations from sunlight is the most common cause of skin cancer. In Australia, where people with pale skin are often exposed to strong sunlight, melanoma is the most common cancer diagnosed in people aged 15–44 years. Substances or foods irradiated with electrons or electromagnetic radiation (such as microwave, X-ray or gamma) are not carcinogenic. In contrast, non-electromagnetic neutron radiation produced inside nuclear reactors can produce secondary radiation through nuclear transmutation. Chemicals used in processed

neg: Gene–environment interaction to gain a better understanding of various phenomena. In genetic epidemiology, gene–environment interactions are useful for understanding some diseases. Sometimes, sensitivity to environmental risk factors for a disease are inherited rather than the disease itself being inherited. Individuals with different genotypes are affected differently by exposure to the same environmental factors, and thus gene–environment interactions can result in different disease phenotypes. For example, sunlight exposure has a stronger influence on skin cancer risk in fair-skinned humans than in individuals with darker skin. These interactions are of particular interest to genetic epidemiologists for predicting disease rates and methods of prevention with

neg: Health effects of sunlight exposure 8,000 deaths due to metastatic melanoma that occur annually in the United States. The use of sunbeds is reported by the World Health Organization to be responsible for over 450,000 cases of non-melanoma skin cancer and over 10,000 cases of melanoma every year in the U.S., Europe, as well as Australia. Lifetime cumulative UV exposure to skin is also responsible for significant age-associated dryness, wrinkling, elastin and collagen damage, freckling, age spots and other cosmetic changes. The American Academy of Dermatology advises that photoprotective measures be taken, including the use of sunscreen, whenever one is exposed to the sun. Short-term

neg: Health in Australia being of the skin, unlike in Canada or US where skin cancer is 2-3 times less common because of less intense sunlight. Other issues include compensation for victims of asbestos exposure related disease, lead exposure due to inhalation of lead based paints and the slow development of HealthConnect. The provision of adequate mental health services and the quality of aged care, are other problems in some parts of the country. In an effort to boost vaccination rates in Australia, the Australian government decided that starting on 1 January 2016, certain benefits (such as the universal 'Family Allowance' welfare payments for

neg: Potato roots, berries, peel [skin plus outer cortex of tuber flesh], stems, and tuber flesh.) Exposure to light, physical damage, and age increase glycoalkaloid content within the tuber. Cooking at high temperatures—over —partly destroys these compounds. The concentration of glycoalkaloids in wild potatoes is sufficient to produce toxic effects in humans. Glycoalkaloid poisoning may cause headaches, diarrhea, cramps, and, in severe cases, coma and death. However, poisoning from cultivated potato varieties is very rare. Light exposure causes greening from chlorophyll synthesis, giving a visual clue as to which areas of the tuber may have become more toxic. However, this does not

neg: Urushiol-induced contact dermatitis is less common. Urushiol causes an eczematous contact dermatitis characterized by redness, swelling, papules, vesicles, blisters, and streaking. People vary greatly in their sensitivity to urushiol. In approximately 15% to 30% of people, urushiol does not trigger an immune system response, while at least 25% of people have a very strong immune response resulting in severe symptoms. Since the skin reaction is an allergic one, people may develop progressively stronger reactions after repeated exposures, or have no immune response on their first exposure but show sensitivity on subsequent exposures. Approximately 80% to 90% of adults will get a rash if

neg: Innate lymphoid cell T cells. In response to allergen exposure in the lungs, ILC2s produce IL-13, a necessary cytokine in the pathogenesis of allergic reactions. This response appears to be independent of T and B cells. Further, allergic responses that resemble asthma-like symptoms have been induced in mice that lack T and B cells using IL-33. It has also been found that ILC2s are present in higher concentrations in tissues where allergic symptoms are present, such as in the nasal polyps of patients with chronic rhinosinusitis and the skin from patients with atopic dermatitis. NK cells express many cell-surface receptors that can be

neg: Skin care wrinkle formation. Sunscreen can protect the skin from sun damage; sunscreen should be applied at least 20 minutes before exposure, and should be re-applied every four hours. Sunscreen should be applied to all areas of the skin that will be exposed to sunlight, and at least a tablespoon (25 ml) should be applied to each limb, the face, chest, and back, to ensure thorough coverage. Many tinted moisturizers, foundations and primers now contain some form of SPF. Sunscreens may come in the form of creams, gels or lotions; their SPF number indicates their effectiveness in protecting the skin from the

neg: Eric John Stark covers from the Paizo Publishing Planet Stories line : years of exposure to heightened sunlight on the planet Mercury has permanently given Stark very dark, almost black skin. His skin is "almost as dark as his black hair" and an antagonist refers to him scornfully as a "great black ape". The darkness of Stark's skin is reiterated in "Enchantress of Venus". Brackett's other Mercurian characters also have black skin (e.g. Jaffa Storm in "The Nemesis from Terra"). Brackett's professional illustrators have universally drawn Stark as light-skinned, even sometimes blond . Brackett's use of a strong, independent, and attractive black-skinned character

neg: Ultraviolet not require a synchrotron, yet can produce UV at the edge of the X-ray spectrum. Synchrotron light sources can also produce all wavelengths of UV, including those at the boundary of the UV and X-ray spectra at 10 nm. The impact of ultraviolet radiation on human health has implications for the risks and benefits of sun exposure and is also implicated in issues such as fluorescent lamps and health. Getting too much sun exposure can be harmful, but in moderation, sun exposure is beneficial. There is no doubt that a little sunlight is good for you! But 5 to 15

neg: Contact dermatitis Contact dermatitis Contact dermatitis is a type of inflammation of the skin. It results from either exposure to allergens (allergic contact dermatitis) or irritants (irritant contact dermatitis). Phototoxic dermatitis occurs when the allergen or irritant is activated by sunlight. Diagnosis of allergic contact dermatitis can often be supported by patch testing. Contact dermatitis is a localized rash or irritation of the skin caused by contact with a foreign substance. Only the superficial regions of the skin are affected in contact dermatitis. Inflammation of the affected tissue is present in the epidermis (the outermost layer of skin) and the outer dermis

neg: Intermammary cleft affects fair skinned middle-aged to elderly women. It is characterized by hypopigmentation, hyperpigmentation, telangiectasias and superficial skin atrophy (occasional itching is reported), is another condition caused by long exposure to sunlight. Intermammary cleft can get attacked by plaque type psoriasis, which can in turn can cause erythematosus. Hidradenitis suppurativa (HS) is a non-contagious chronic skin disease which affects intertriginous skin of apocrine sweat gland bearing areas like the inframammary fold and intermammary sulcus. It is characterized by clusters of abscesses, epidermoid cysts, sebaceous cysts, pilonidal cysts. Prurigo pigmentosa is a rare skin condition of unknown cause that affects depressed places

neg: UV-B lamps Glo and used for a period of 10–12 hours per day to give the required exposure. These lamps simulate the sun spectrum and thus produce mostly visible light and a very small amount of UV-B light, like the sun. UV-B treatments for treating skin diseases (psoriasis, vitiligo, atopic dematitis, etc.) are given in a very low dosage. The treatments take only few minutes. The maximum dose of broadband UV-B is 0.5 Joules per treatment. The maximum dose for narrowband UV-B is 3 Joules per treatment. This low dosage does not increase the risk of skin cancer and UV-B phototherapy remains

neg: Melanoma from northern Europe that have a large amount of direct, intense sunlight that the skin of the settlers is not adapted to, most notably Australia. Exposure during childhood is a more important risk factor than exposure in adulthood. This is seen in migration studies in Australia. Having multiple severe sunburns increases the likelihood that future sunburns develop into melanoma due to cumulative damage. The sun and tanning beds are the main sources of UV radiation that increase the risk for melanoma and living close to the equator increases exposure to UV radiation. A number of rare mutations, which often run

neg: Zinc peroxide or inhalation. It has been shown to be corrosive to skin. Prolonged exposure may result in skin burns and ulcerations. Over-exposure by inhalation may cause respiratory irritation. Skin inflammation is characterized by itching, scaling, reddening, or, occasionally, blistering. Zinc peroxide is toxic to lungs and mucous membranes. Repeated or prolonged exposure can produce organ damage. Repeated or prolonged inhalation of vapors may lead to chronic respiratory irritation. Zinc peroxide Zinc peroxide (ZnO) appears as a bright yellow powder at room temperature. It was historically used as a surgical antiseptic. More recently zinc peroxide has also been used as an oxidant

neg: Ultraviolet to provide sensations of happiness, well being and serenity to human beings. UV rays also treat certain skin conditions. Modern phototherapy has been used to successfully treat psoriasis, eczema, jaundice, vitiligo, atopic dermatitis, and localized scleroderma. In addition, UV light, in particular UVB radiation, has been shown to induce cell cycle arrest in keratinocytes, the most common type of skin cell. As such, sunlight therapy can be a candidate for treatment of conditions such as psoriasis and exfoliative cheilitis, conditions in which skin cells divide more rapidly than usual or necessary. In humans, excessive exposure to UV radiation can result

neg: Progeroid syndromes Japan, North Africa, and the Middle East. There have been 830 published cases from 1874 to 1982. The disorder presents at infancy or early childhood. Xeroderma pigmentosum mostly affects the eye and skin. Individuals with XP have extreme sensitivity to light in the ultraviolet range starting from one to two years of age, and causes sunburn, freckling of skin, dry skin and pigmentation after exposure. When the eye is exposed to sunlight, it becomes irritated and bloodshot, and the cornea becomes cloudy. Around 30% of affected individuals also develop neurological abnormalities, including deafness, poor coordination, decreased intellectual abilities, difficulty swallowing

neg: Optical media preservation exposure of ROM discs to light is "clouding" or "coloring" of the polycarbonate substrate. CD-R, DVD-R, DVD+R, CD-RW, DVD-RW, DVD+RW and DVD-RAM discs are all affected by exposure to ambient heat as well as heat build-up due to direct sunlight. A CD-R’s data layer is made of dye that degrades at high temperatures, becoming less transparent so that pits and lands are read incorrectly, making the data unreadable. UV rays in sunlight are energetic enough to produce a photochemical reaction that changes the optical properties of the dye. RW and RAM discs' data layers are composed of a phase-changing film

neg: Freckle into higher latitudes where incoming sunlight has lower UV light content. The adaptation of lighter skin is needed so that individuals in higher latitudes can still absorb enough UV for the production of vitamin D. Freckled individuals tend to tan less and have very light skin, which would have helped the individuals that expressed these genes absorb vitamin D. "Ephelides" describes a freckle which is flat and light brown or red and fades with reduction of sun exposure. Ephelides are more common in those with light complexions, although they are found on people with a variety of skin tones. The

neg: Notobubon galbanum It is usually found at medium- to high-altitudes in partially shady and damp areas but will also grow at lower altitudes and in areas of direct sunshine. The plant grows in the winter rainfall areas, which are relatively frost-free and have well-drained soils. The surface of the plant is covered in a mix of chemicals including psoralen, xanthotoxin and bergapten that causes a phototoxic reaction resulting in blistering two or three days after exposure. The moment of exposure is innocuous, without any untoward sensations to the unwary. Exposure of the affected skin to ultraviolet light, such as contained in sunlight,