There is global interest in both the beneficial and detrimental health effects of ultraviolet-C (UV-C) radiation in the wavelength range 200-230 nm (known as Far-UV-C). Technology using Far-UV-C is proposed as a highly effective control measure for reducing the transmission of COVID-19 by inactivation of the SARS-CoV-2 virus. Although studies have shown irradiation of skin with 254 nm UV results in DNA damage in the epidermal basal layer, irradiation with Far-UV-C (222 nm) radiation shows minimal DNA damage and only in the granular layer. It has also been shown that even high doses of Far-UV-C exposure to human skin do not induce erythema. However, the effects of Far-UV-C on wound healing responses and the immune system are, to the best of our knowledge, unknown. It is well-reported that both ultraviolet B (UV-B; 280-315 nm) and ultraviolet-A (UV-A; 315-400 nm) wavelengths have effects on cutaneous Langerhans cells (LC), inducing migration from the epidermis to the draining lymph nodes, thereby suppressing skin immune function. Here we present data in an immunocompetent ex vivo human skin model utilising a range of skin types (including skin of color) demonstrating little or no impact of 222 nm UV-C on both i) the skins ability to heal 2 mm biopsy wounds and ii) the cutaneous immune system, as assessed by Langerhans cell migration, at doses of up to 3,000 mJ/cm2 (current ICNIRP and ACGIH TLVs being 23 and 450 mJ/cm2 respectively). These results support the safety of filtered Far-UV-C use, which could have a transformative effect on public health, allowing effective virus inactivation and reduction of transmission independent of human behavior.

LB067 - Ex vivo skin safety testing to enable far-UV-C technologies

The scientific meeting of the European Society for Dermatological Research (ESDR) is held yearly, usually in September. With an international attendance of more than 1000 skin scientists from around the globe, the four-day event includes short oral presentations from peer-reviewed abstracts, keynote lectures from international experts, sponsored symposia, satellite programs, educational events as well as an important focus on posters, networking and building collaborations amongst scientists. For more information about this year’s meeting visit our website.