US EPA

8223786 

Journal Article 

Effects of UVR on immune response of skin and evaluation of sunscreen 

Zhou, H; Zhu, H; Zhang, Z 

1998 

16 

2 

27-36 

English 

1. It is an important work to monitor the ground level UVR, especially for a long time. The highest means UVR irradiate value at noon is observed in July (UV-420, 6814 μW/cm2; UV-365, 3184 μW/cm2) or August (UV-297, 31.5 μW/cm2) at shanghai. The trend showed that radiation power of summer > that of autumn > that of spring > that of winter. The highest means UVR of a day appeared around noon. The UVA is nearly 100 times higher than UVB. 2. Sun protection factor (SPF) is an important index to evaluate the effectiveness of sunscreen. It is urgent to establish the standards on evaluating the efficacy of sunscreen in our country. We have set up in vivo and in vitro methods to detect the SPF of sunscreen. 3. Though majority of people realized the harmful effects of UVR, they neglected to protect themselves from exposure to UVR. It is urgent to take some propaganda against UVR. 4. UVA radiation has the capacity to damage collagen I and collagen III. It is believed that UVA plays a important role in the induction of photodamage of the skin. 5. UVR can suppress immune responses of the skin. Cis-urocanic acid (cis-UCA) has been suggested as a photoreceptor for UV and has been demonstrated to suppress immune responses in delayed type hypersensitivity (DTH) in mice. 

Epidemiology; Immunization; Sunscreens; Ultraviolet radiation