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.
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24-.What is Transepidermal water loss (TEWL)?

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What is Transepidermal water loss
What is Transepidermal water loss (TEWL)?It is the indicator to evaluate your skin hydration.


How do you understand the water barrier function of human skin? Try the transepidermal water loss (TEWL)indicator. It is the way to monitor the skin hydration.
Water passes from inside a body through the epidermal layer to the surrounding atmosphere via diffusion and evaporation processes.  It (TEWL)would vary with the skin barrier (wounds, scratches, burns, exposure to solvents or surfactants, extreme dryness), the conditions of weather such as humidity, temperature, season, and moisture content of the skin.  The continuous process(TWEL) is difficult to control artificially and it is an indicator of skin conditions about hydration.

Transepidermal water loss indicates the condition of skin at the moment. For example, when the climate is dry, TEWL value increase. When we has little water in the skin, TEWL value increases. To sum up, Any thing that assaults or insults the skins will increase TWEL indicator. To prevent under the situations to damage the skin and maintain the the indicator (TWEL) between proper ranges is the rule of thumb. 

Usually it is measured by a gadget like the above picture. 
The unit of TEWL: g/(m2 h)
(Expressed in gram per square meter and per hour)
1. Water will pass through dermis to epidermis and excrete to out of the skins.
2. The stratum corneum plays an important role during the water loss process.
3. Water will beat around the barriers of lipids.
4. The more perfect the stratum corneum of epidermis, the higher the water fulfill in skin and the 
lower the TEWL value(Transepidermal water loss ).   

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help to find the specific skincare product ingredients by "glamskin" App

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