The role and safety of UVA and UVB in UV-induced skin erythema

Jing-Wen Yang; Guo-Biao Fan; Fei Tan; Hai-Mei Kong; Qing Liu; Ying Zou; Yi-Mei Tan

doi:10.3389/fmed.2023.1163697

The role and safety of UVA and UVB in UV-induced skin erythema

Front Med (Lausanne). 2023 Jun 27:10:1163697. doi: 10.3389/fmed.2023.1163697. eCollection 2023.

Authors

Jing-Wen Yang^#^{1

2

3}, Guo-Biao Fan^#⁴, Fei Tan¹, Hai-Mei Kong^{1

2

3}, Qing Liu⁴, Ying Zou^{1

2

3}, Yi-Mei Tan^{1

2

3

5}

Affiliations

¹ Department of Skin and Cosmetics Research, Shanghai Skin Disease Hospital, School of Medicine, Tongji University, Shanghai, China.
² Professional Technical Service Platform for Clinical Evaluation of Skin Health Related Products, Shanghai Science and Technology Commission, Shanghai, China.
³ MPA Key Laboratory for Monitoring and Evaluation of Cosmetics, Shanghai, China.
⁴ Department China Regulatory Affairs, LVMH Perfume and Cosmetic (Shanghai) Limited Company, Shanghai, China.
⁵ Human Phenome Institute, Fudan University, Shanghai, China.

^# Contributed equally.

Abstract

Background: Different wavelengths of ultraviolet (UV) light cause skin damage through different mechanisms. Minimal erythema dose (MED) is usually used to clinically evaluate skin sensitivity to ultraviolet radiation by inducing skin erythema using ultraviolet B (UVB) or ultraviolet A (UVA) + UVB.

Aims: In this study, we detected changes in the blood flow at the MED erythema caused by UVB and UVA + UVB radiation through optical coherence tomography (OCT) to explain the role of different bands of ultraviolet rays in erythema induction.

Methods: Two MED irradiation areas on the subjects' back were irradiated with UVB alone or UVA + UVB (UVA: UVB = 8:1). The absolute energy of UVB remained the same in UVB and UVA+UVB. At 24 h after the irradiation, the changes in the blood flow in the MED area were detected using OCT.

Results: Compared with the blank control, the maximum blood flow depth, blood flow peak, and total blood flow of UVB-MED and UVA+UVB-MED were significantly increased. Notably, the maximum blood flow depth and blood flow peak of UVB-MED were higher than UVA+UVB-MED. There was no significant difference in total blood perfusion between UVA+UVB-MED and UVB-MED. Under the same UVB energy, the skin erythema caused by UVA + UVB was weaker than UVB alone.

Conclusions: The analysis of local blood flow by OCT showed that the peak and maximum depth of local blood flow caused by UVB alone were significantly higher than UVA + UVB.

Keywords: UVA; UVB; maximum blood flow depth; minimal erythema dose; optical coherence tomography; optical coherence tomography UVA; total blood flow.