1. EFFECTS OF ULTRAVIOLET RADIATION Henry W. Lim, MD Co-Chair National Council on Skin Cancer Prevention

2. PRESENTER Chairman, Department of Dermatology, Henry Ford Hospital, Detroit, MI Photodermatology

3. DISCLOSURE Consultant : La Roche- Posay/L’Oreal, Orfagen, Dow Pharmaceutical Sciences Investigator: Johnson & Johnson

4. ELECTROMAGNETIC RADIATION

5. ULTRAVIOLET RADIATION UV λ (nm)Properties UVC200-290Germicidal UVB290-320Sunburn UVA 320-400Pigment darkening, tanning

6. EFFECTS OF UV DNA damage Erythema Tanning Vitamin D synthesis Immunosuppression Skin cancer

7. EFFECTS OF UV DNA damage

8. UV AND DNA DAMAGE UVB: Direct effect Cyclobutane-pyrimidine dimers Bolognia, et al. Dermatology. 2008

9. UV AND DNA DAMAGE (Agar NS, PNAS 4/04; 101:4954; Budiyanto A, P&P10/02; 76:397) UVA: Indirect mechanism Absorption by skin chromophores → reactive oxygen species → reacts with guanine → oxidative products (8- oxoG, 8-oxo-dG) Mutagenic

10. EFFECTS OF UV DNA damage Erythema

11. ERYTHEMA Primarily the effect of UVB Peaks at 24 hrs

12. EFFECTS OF UV DNA damage Erythema Tanning

13. MECHANISMS OF TANNING (Hönigsmann H, PPP 4/02; 18:75) UV: activation of tyrosinase UV  DNA damage  nucleotide fragments excised in repair  stimulate melanogenesis

14. ERYTHEMA & TANNING UVB: Erythema > tanning UVA: Tanning > erythema Tanning is an indication that DNA damage has occurred There is no “safe tan”

15. EFFECTS OF UV DNA damage Erythema Tanning Vitamin D synthesis – Action spectrum: UVB

16. EFFECTS OF UV DNA damage Erythema Tanning Vitamin D synthesis Immunosuppression Skin cancer

17. UV: IMMUNOSUPPRESSION AND SKIN CANCER (International Agency for Research on Cancer Working Group on artificial ultraviolet light and skin cancer. Green A, et al. Int J Cancer 3/07; 120:1116) UV: immunosuppressive Chronic UV exposure: – Photoaging changes – Squamous cell carcinoma – Basal cell carcinoma Tanning bed users: – Melanoma – Squamous cell carcinoma

18. NATURAL AND ARTIFICIAL UV DNA damage, immunosuppression, skin cancer WHO: UV is carcinogen WHO: UV tanning beds: “carcinogenic to humans.” (El Ghissassi F, Lancet Oncol 7/09; 10: 751)

19. NCSCP RECOMMENDATIONS To reclassify sunlamps for tanning as Class II devices To impose special controls: user labeling and user registry To prohibit use by consumers younger than 18 years To require license for facilities at which sunlamps may be used To have training and certification of operators

20. www.skincancerprevention.org