The biological effects of ultraviolet radiation on the human body
Ultraviolet rays have biological effects,which are well-known to many people.It refers to the physiological changes that occur in the human body or organism when ultraviolet rays are irradiated.For example,ultraviolet radiation on the human body causes pigmentation and darkening of the skin.For example,after being exposed to a certain wavelength of ultraviolet radiation,the human body's ability to resist diseases is enhanced,the skin's regenerative ability is enhanced,and the speed of hair growth is accelerated.
UV erythema effect
The acute redness of the skin caused by ultraviolet radiation.It can have a beneficial effect on the nervous,endocrine,and circulatory systems.The average threshold exposure radiation is 300J?m-2 to 500J?m-2***Sensitivity wavelength 297nm.
After a certain dose of health care ultraviolet radiation is irradiated on the skin,after a certain incubation period,the skin will experience erythema reaction,which is the appearance of red spots with clear boundaries.This is due to the expansion of capillaries caused by the decomposition of skin surface cells by ultraviolet radiation to produce substances such as histamine,which is related to the endocrine system,nervous system,and body fluids.The erythema reaction of ultraviolet radiation has two sensitive wavelength regions,namely,the wavelength of 297nm and 254nm ultraviolet radiation can easily cause erythema on human skin.Therefore,when the dose of ultraviolet radiation is constant,the erythema reaction is closely related to the wavelength of ultraviolet radiation.
Direct pigmentation effect
The biological effect of ultraviolet radiation with wavelengths ranging from 320nm to 400nm is weak,but it causes skin darkening and significant pigmentation after irradiation on the human body,which is called the black spot effect of ultraviolet radiation.The ultraviolet rays in this band strongly stimulate the skin,accelerate skin metabolism,enhance skin growth,and thicken the skin.Therefore,this band of ultraviolet radiation is an important treatment for many skin diseases,such as psoriasis(psoriasis),vitiligo,and other diseases,which are treated with this band of ultraviolet radiation.Artificial skin coloring,its black color is caused by the black spot effect of ultraviolet radiation.
