Uvc radiation skin#

As has been recognized for some time, UVC radiation can damage the superficial tissues of the eye, and care must be taken to avoid excessive exposures of the eye. With increasing germicidal uses of man-made UVC radiation, perhaps especially in hospital settings where there is a strong concern about the spread of harmful bacteria, it is likely that more human exposures will occur, and future studies may show some links with disease that we have not so far identified.

Uvc radiation skin#

This would be true especially in an abraded area of skin or a region of a significant flesh wound.īecause UVC is strongly attenuated by atmospheric gases, no significant irradiation of human beings on earth results from natural sources.

In areas of reduced dead-skin thickness and intense radiation, however, UVC radiation might reach live skin tissue and could produce erythema and possibly other undocumented effects. It is true that the dead skin on most of the human body is sufficient to absorb UVC radiation almost completely. To my knowledge, UVC radiation has not been shown to be a cause of human skin cancer or other types of human cancer, although some experiments with mice have demonstrated a causative link between squamous cell cancer and UVC irradiation. It is common that photon absorption by particular atoms or molecules may be small at a given energy, increase with increasing energy, and then decrease again at yet higher energies, so it is not surprising that some higher-energy UV radiation may be more strongly absorbed than lower-energy UV. Atomic or molecular excitation may occur as a result of the absorption, or an electron may be ejected from an atom when the incoming photon energy exceeds the binding energy of the electron in the atom. The absorption at particular wavelengths may be associated with resonance-type effects in which the gaps between certain energy states in an atom or molecule are nearly matched by the energies of the incoming photons. The preferential absorption of particular energy photons by materials, both organic and inorganic, is evident throughout the electromagnetic spectrum from microwaves through infrared and visible light, ultraviolet, x rays, and gamma rays. The UVC radiation is sufficiently energetic that individual photons may produce chemical bond breakage and ionization of some atoms and molecules. The strong absorption by organic molecules, including DNA, leads to severe damage to the molecule and to the organism's reproductive processes, leading to the death of the microbes.

This is why the common 254 nm sources have become so popular for germicidal/disinfectant applications. The shorter-wavelength, higher-energy UV radiation associated with the UVC category is very strongly absorbed by most organic materials.