Protection effect of cosmetics on human skin under simulated rigorous environment.
OBJECTIVE
The efficacy of cosmetics on human skin measured under normal mild laboratory environment might be discounted by exterior environment factors such as wind, UV exposure, etc. Few studies have focused on the 'genuine' efficacy of cosmetics on human skin during exposure to external rigorous environment. The aim of this study was to develop a model for the evaluation of the efficacy of cosmetics on human skin under simulated rigorous environment.


METHODS
We measured skin water content and transepidermal water loss (TEWL) before and after products application under simulated windy and sub-erythema UV exposure treatment in a constant temperature and humidity laboratory.


RESULTS
The results showed that the products had higher water content and lower TEWL at 2, 4 and 8 h of products application, and ameliorated the skin moisturization situation after a 3-week continuous use of the products. In addition, the products might protect the skin to maintain the normal water content and TEWL under the simulated windy or sub-erythema UV exposure treatment in our laboratory when compared with untreated area.


CONCLUSIONS
Our data indicate that this model may provide a more accurate evaluation for the genuine moisturizing effect of cosmetics under external natural climate.
Cheng
Yan
Y
Beijing Sino-German Union Cosmetic Institute Co, Chinese Academy of Inspection and Quarantine, Beijing, China.
Dong
Yi-Yang
YY
Dong
Mei-Xian
MX
Wang
Chao
C
Su
Ning
N
Sun
Yuan-Tao
YT
Liu
Juan
J
Zheng
Hong-Yan
HY
Schrader
Andreas
A
Rohr
Mathias
M
Liu
Wei
W
D000328:Adult; D002610:Cheek / Q000502:physiology; D003358:Cosmetics / Q000493:pharmacokinetics / Q000494:pharmacology*; D025802:Electric Capacitance; D004643:Emollients / Q000493:pharmacokinetics / Q000494:pharmacology*; D004780:Environment, Controlled; D005260:Female; D005542:Forearm / Q000502:physiology; D006801:Humans; D012867:Skin / Q000187:drug effects* / Q000528:radiation effects; D012879:Skin Physiological Phenomena; D014466:Ultraviolet Rays; D014870:Water Loss, Insensible; D014919:Wind
D003358:Cosmetics; D004643:Emollients