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80.Restricted ingredients in cosmetic and skin care products

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Restricted ingredients in cosmetic and skin care products by regulation. Ingredient Potential toxicity Hexachlorophene Neurotoxic effects Ability to penetrate human skin Mercury compounds Accumulation in the body Skin irritation Allergic reactions Neurotoxicity Bithionol Photocontact sensitization Halogenated salicylanilides Photocontact sensitization Chlorofluorocarbon propellants Hazardous to human health Chloroform Plausible carcinogenicity Vinyl chloride Plausible carcinogenicity Zirconium-containing complexes Lung toxicity Methylene chloride Plausible carcinogenicity help to find the specific skincare product ingredients by "skin+" App.

47.UVR: the differenes among UVA, UVB and UVC

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UV= UVC+UVB+ UVA UV dominates 10% of sun light energy. (UVB=5% of UV, UVA= 95% of UV) The magnitude of UV is associated with the latitude, height, time, season, and climate. UVC: Wave length is 100-280nm. The shorter wave length, the more energy it has. It is the most harmful sun light for skin. Fortunately, most of them are filtered by the atmosphere. However, the global warming and climate change cause the depletion of ozone layers nowadays. UVC will be easy to damage human skin. UVB: Wave length is 280-320nm. Around 16% will penetrate epidermis to dermis The symptoms are sunburn, redness, and skin cancer. Manifestation: persistent pigment darkening UVA: Around 57% will penetrate epidermis to dermis The radiation will cause the free radical to damage the elastin and collagen in dermis. This is called photo aging and also results the wrinkles. Manifestation: immediate pigment darkening UVB sunburn is caused by the culprit red skin drying and ha...

46.Skin surface properties_Roughness of skin

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There are many methods to detect the skin health, skin surface properties, skin color, skin color type, and hair conditions. They are non-intrusive. Skin surface properties l    Roughness of skin Use a machine to evaluate the friction of skin There are the methods to measu re skin friction: the sled, the spinning drum or spool, and the rotating disk. The rule to define friction is by dragging or spinning  or rotating the edge against the skin to encounter t he resistance by the machine . This would give the friction value of the skin . Sebum Sebum is the liquids excreted by the sebaceous glands. It has the function to main skin’s barriers with mild bacterial and antifungal properties. Howerver, excess sebum could block the follicle surface. Sebumeter         The principle of the measurement is the observation the device opacity becomes transparent as its surface is covered by lipids.  Optical method Measure the lipid...

45.Why do we get old(5)?

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Why do we get old? The genes are the important rue of aging. How do they do? Why do human age? Some elders are still healthy, but some are weak and sick. The scientists do not come to the definitive conclusions yet. There are some aging theories as the following.    The aging theories _part5 Genetic Endowment A set of genes determine your congenital disease, life expectancy, many degenerative diseases, etc. Gene has two copies, and one inherited from each parent. So gene is the essential factor of age. Telomere’s length Telomere is the end of a chromosome which protects the end of the chromosome from deterioration and fusion with the other chromosome. The length of telomere will be shorter as cell division each time . If the length of telomere is shorter than a significant length, it will lose its protecting function for chromosome. Cell division will be  no more, and the cells age and die.  Longevity gene The scientists discover DAF-2 gene will cause cel...

44.The surfactants in cosmetics and skin care products(2)

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The surfactants in cosmetics and skin care products. The following is the non-ionic surfactant .  Non-ionic surfactant Function: emulsifier Non-ionic surfactant is the reaction of alcohol and fatty acid. The alcohols are Glycol ( Ethylene, EG), Propylene Glycol(PG), Glycerine(glycerol), Sorbitol, and Polyoxyethylene (POE). It can be applied in anionic surfactant and amphoteric surfactant as detergent. If it is added in cationic surfactant as well, the function of the skin care and hair products would be with cleaning and softening the skin characters. 1.       Alkanolamide 1.1   coconut fatty acid diethanolamide 1.2   lauric aciddiethanolamide, Cocamide DEA 1.3   Lauric acid monoethanolamide, cocamide MEA 2.       Amine oxide Lauryl dimethyl amino oxide 3.       Alkyl polyglucoide Alykyl poplyglucoside (lauryl poplyglucose, APGs) 4.     ...

43.The surfactants in cosmetics and skin care products(1)

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The surfactants used in cosmetics and skincare products more frequently nowadays as the following. The surfactants for cosmetics and skincare products not only need to consider the safety, but also need to pay attention to the influence of skin. The emulsifier should prevent skin allergy. For example, Sodium Lauryl sulfate (SLS) of surfactant ingredients is well to remove dirt, but would be over remove the lipids of skin. It is only suitable for the detergent.       Ionic surfactant     Anionic surfactant Main functions: clean dirt & as the blowing agent 1.       Sulfosuccinate ester     Disodium laureth sulfosuccinate     Disodium lauramido MEA-sulfosuccinate     Dioctyl sodium sulfosuccinate     Disodium oleamido MIPA sulfosuccinate 2.       Alkyl phosphate Mild to remove oils. It is better to adjust to weak alkylinity and neut...

42.Why do we get old? (4)

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Why do we get old? What are the mitochondrial damage and free radical damage? Why do human age? Some elders are still healthy, but some are weak and sick. The scientists do not come to the definitive conclusions yet. There are some aging theories as the following.    The aging theories_part4 Mitochondrial damage Mitochondrial DNA converts chemical energy from food into cells. It maintains our daily life and repairs the damaged cells. As time goes by, mitochondrial DNA will be damaged such as the influence of environment , binge eating , etc. But it will not be so easy to repair as young age .Then the body will be out of the frying pan and into the fire. Free radical damage A free radical is any atom or molecule that has a single unpaired electron in an outer shell. The  free radical is unstable , and it will tend to catch an electron from the other atom or molecule. When it catches an electron, it will affect the function of the original tissue o...

41.Skin health_rate of water loss

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There are many methods to detect the skin health, skin surface properties, skin color, skin color type, and hair conditions. They are non-intrusive. Skin health l    Rate of water loss Use a device to evaluate TEWL (trans-epidermal water loss). This measurement can be representative of stratum corneum function if there is no sweat on the skin.  TEWL(trans-epidermal water loss) is an index to define the hydration of skin. Unit: g/ m 2 h The device could be closed-chamber method, ventilated-chamber method, and open-chamber method. TEWL measurement follow diffusion laws, and the TEWL results would depend on the ambient relative humidity, the stratum corneum barrier integrity, the temperature, and inversely on the stratum corneum thickness . closed-chamber method This method is applied a capsule on the skin to collect water vapor from skin surface. The relative humidity inside is record first. The change in vapor loss concentration is initially flat an...

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