Ultraviolet designation. How infrared rays differ from ultraviolet rays

Ultraviolet radiation from the Sun and artificial sources, depending on the wavelength, is divided into three ranges:

• - region A - wavelength 400-320 nm (long-wave ultraviolet radiation UV-A);
• - region B - wavelength 320-275 nm (medium-wave ultraviolet radiation UV-B);
• - region C - wavelength 275-180 nm (short-wave ultraviolet radiation UV-C).

There are significant differences in the action of long, medium and short-wave radiation on cells, tissues and the body.

Area A (UV-A) long-wave radiation has a variety of biological effects, causing skin pigmentation and fluorescence of organic substances. UV-A - rays have the greatest penetrating ability, which allows some atoms and molecules of the body to selectively absorb the energy of UV radiation and pass into an unstable excited state. The subsequent transition to the initial state is accompanied by the release of light quanta (photons) capable of initiating various photochemical processes, primarily affecting DNA, RNA, and protein molecules.

Phototechnical processes cause reactions and changes on the part of various organs and systems, which form the basis of the physiological and therapeutic effect of UV rays. Shifts and effects occurring in an organism irradiated with UV rays (photoerythema, pigmentation, desensitization, bactericidal effect, etc.) have a clear spectral dependence (Fig. 1), which serves as the basis for the differentiated use of various parts of the UV spectrum.

Figure 1 - Spectral dependence of the most important biological effects of ultraviolet radiation

Irradiation with medium-wave UV rays causes photolysis of the protein with the formation of biologically active substances, and exposure to short-wave rays often leads to coagulation and denaturation of protein molecules. Under the influence of UV rays of the B and C ranges, especially in high doses, changes in nucleic acids occur, as a result of which cellular mutations may occur.

At the same time, long-wavelength rays lead to the formation of a specific photoreactivation enzyme that promotes the reduction of nucleic acids.

1. The most widely used UV radiation is for medicinal purposes.
2. UV rays are also used to sterilize and disinfect water, air, rooms, objects, etc.
3. Their use is very common for prophylactic and cosmetic purposes.
4. UV radiation is also used for diagnostic purposes, to determine the reactivity of the body, in luminescent methods.

UV radiation is a vital factor, and its long-term deficiency leads to the development of a kind of symptom complex with "light starvation" or "UV deficiency". Most often it manifests itself in the development of vitamin D deficiency, a weakening of the protective immunobiological reactions of the body, exacerbation of chronic diseases, functional disorders of the nervous system, etc. workshops, engine rooms and in the Far North.

Ultraviolet irradiation

Ultraviolet irradiation is produced by various artificial products with different wavelengths λ. The absorption of UV rays is accompanied by a number of primary photochemical and photophysical processes, which depend on their spectral composition and determine the physiological and therapeutic effect of the factor on the body.

Longwave ultraviolet(DUV) rays stimulate the proliferation of cells of the malpighian layer of the epidermos and decarboxylation of tyrosine, followed by the formation of a spiny layer in the cells. Next comes the stimulation of the synthesis of ACTH and other hormones, etc. Various immunological shifts are obtained.

DUV rays have a weaker biological effect, including erythema-forming, than other UV rays. To increase the sensitivity of the skin to them, photosensitizers are used, most often compounds of the furocoumarin series (puvalan, beroxan, psoralen, amminofurin, etc.)

This property of long-wavelength radiation allows it to be used in the treatment of skin diseases. The method of PUVA therapy (salicylic alcohol is also used).

Thus, you can highlight the main characteristics healing effects DUV rays:

1. The healing effects are

• - photosensitizing,
• - pigment-forming,
• - immunostimulating.

1. DUV rays, like other areas of UV radiation, cause a change in the functional state of the central nervous system and its higher part of the cerebral cortex. Due to the reflex reaction, blood circulation improves, the sectorial activity of the digestive organs and the functional state of the kidneys increase.
2. DUV rays affect metabolism, primarily mineral and nitrogen.
3. Local applications of photosensitizers are widely used for limited forms of psoriasis. Recently, UV-B has been successfully used as a sensitizer as it has a greater biological activity. Combined UV-A and UV-B irradiation is called selective irradiation.
4. DUV rays are used for both local and general exposures. The main indications for their use are:

• - skin diseases (psoriasis, eczema, vitiligo, seborrhea, etc.)
• - chronic inflammatory diseases of internal organs (especially respiratory organs)
• - diseases of the organs of support and movement of various ethnology
• - burns, frostbite
• - sluggish wounds and ulcers, cosmetic purposes.

Contraindications

• - acute anti-inflammatory processes,
• - diseases of the liver and kidneys with severe impairment of their functions,
• - hyperthyroidism,
• - increased sensitivity to UV radiation.

Medium ultraviolet(SUF) radiation has a pronounced and versatile biological effect.

When the quanta of SUV radiation are absorbed in the skin, low-molecular products of protein photolysis and products of lipid peroxidation are formed. They cause changes in the ultrastructural organization of biological membranes, protein-lipid complexes, membrane enzymes and their most important physicochemical and functional properties.

Photodegradation products activate the system of mononuclear phagocytes and cause degranulation of mast cells and basophils. As a result, biologically active substances (kininn, prostaglandinn, heparin, leukotrienes, thromboxanes, etc.) and vasoactive mediators (acetylcholine, histamine) are released in the irradiated area and adjacent tissues, which significantly increase the permeability and tone of blood vessels, and also contribute to the relaxation of smooth muscles. ... Due to humoral mechanisms, the number of functioning skin capillaries increases, the speed of local blood flow increases, which leads to the formation erythomas.

Repeated SUV irradiation can lead to the appearance of rapidly disappearing pigmentation, which contributes to an increase in the barrier function of the skin, increases its cold sensitivity and resistance to the action of toxic substances and unfavorable factors.

Both the erythemal response and other shifts caused by the SUV rays depend not only on the wavelength, but also on the dosage. In phototherapy, it is used in erythemal and suberythemal doses.

Irradiation with SUV rays in suberythemal dosages promotes the formation of vitamin D in the skin, which, after its biotransformation in the liver and kidneys, participates in the regulation of phosphorus-calcium metabolism in the body. SUV irradiation promotes the formation of not only vitamin D1, but also its isomer - ergocalcifemin (vitamin D2). The latter has an antirachitic effect, stimulates the aerobic and anaerobic pathways of cellular respiration. Small doses of SUV rays also modulate the metabolism of other vitamins (A and C) and activate metabolic processes in the irradiated tissues. Under their influence, the adaptive-trophic function of the sympathetic nervous system is activated, the disturbed processes of various types of metabolism, cardiovascular activity are normalized.

Thus, SUV radiation has a pronounced biological effect. Depending on the phase of irradiation, you can get erythema on the skin and mucous membranes, or be treated at a dose that does not cause it. The mechanism of the therapeutic action of erythemal and non-erythemal doses of SUF is different, therefore, the indications for the use of ultraviolet radiation will also be different.

Ultraviolet erythema appears at the site of UV-B irradiation after 2-8 hours and is associated with the death of epidermal cells. The products of photolysis of proteins enter the blood stream and cause vasodilation, skin edema, migration of leukocytes, irritation of numerous receptors, leading to a number of reflex reactions of the body.

In addition, photolysis products that enter the bloodstream have a humoral effect on individual organs, the nervous and endocrine systems of the body. The phenomena of aseptic inflammation gradually subside by the seventh day, leaving behind skin pigmentation at the site of irradiation.

The main therapeutic effects of SUF irradiation:

1. SUF - radiations are vitamin-forming, tropostimulating, immunomodulating - these are suberythemal doses.
2. Anti-inflammatory, analgesic, desensitizing - this is an erythemal dose.
3. Bronchial diseases, asthma, hardening is a non-erythema dose.

Indications for topical application of UV-B (suberythemal and erythemal doses):

• - acute neuritis
• - acute meositis
• - pustular skin diseases (furukul, carbuncle, sycosis, etc.)
• - erysipelas
• - trophic ulcers
• - sluggish wounds
• - bedsores
• - inflammatory and post-traumatic joint diseases
• - rheumatoid arthritis
• - bronchial asthma
• - acute and chronic bronchitis
• - acute respiratory diseases
• - inflammation of the uterine appendages
• - chronic tonsillitis.

Erythema-free zones of ultraviolet radiation of the B spectrum during general irradiation of the body eliminate the phenomenon of D-hypovitaminosis associated with a lack of sunlight. It normalizes phosphorus-calcium metabolism, stimulates the function of the sympathetic-adrenal and pituitary-adrenal systems, increases the mechanical strength of bone tissue and stimulates the formation of callus, increases the resistance of the body's skin and the body as a whole to harmful environmental factors. Allergic and exudative reactions decrease, mental and physical performance increases. Other disorders in the body caused by sun starvation are weakened.

Indications for general use of UV-B (non-erythema doses):

• - D-hypovitaminosis
• - metabolic disease
• - predisposition to pustular diseases
• - neurodermatitis
• - psoriasis
• - bone fractures and impaired callus formation
• - bronchial asthma
• - chronic diseases of the bronchial apparatus
• - hardening of the body.

Contraindications:

• - malignant neoplasms
• - a tendency to bleeding
• - systemic blood diseases
• - thyrotoxicosis
• - active tuberculosis
• - peptic ulcer of the stomach and duodenum in the acute stage
• - hypertension stage II and III
• - far-reaching atherosclerosis of the arteries of the brain and coronary arteries.

Shortwave ultraviolet radiation spectrum(KUV) radiation.

Short-wave UV radiation is an active physical factor, since its quanta have the greatest energy reserve. It is capable of causing denaturation and photolysis of nucleic acids and proteins due to the excessive absorption of the energy of its quanta by various molecules, primarily DNA and RNA.

When acting on microorganisms, on cells, this leads to inactivation of their genome and protein denaturation, which leads to their death.

When KUV rays are emitted, a bactericidal effect occurs, since their direct hit on the protein is fatal for the cells of viruses, microorganisms and fungi.

After a short-term spasm, the KUV rays cause dilation of blood vessels, especially subcapellar veins.

Indications for the use of KUV radiation:

• - irradiation of wound surfaces
• - bedsores and almond-shaped niches after tonsillectomines with a bactericidal chain
• - sanitation of the nasopharynx in acute respiratory diseases
• - treatment of otitis externa
• - air disinfection in operating rooms, procedure rooms, inhalers, intensive care units, patient wards, children's institutions and schools.

Skin and its function

Human skin makes up 18% of the human body weight and has a total area of ​​2m2. The skin consists of three anatomically and physiologically closely interconnected layers:

• - epidermis or cuticle
• - dermis (skin itself)
• - hypodermis (subcutaneous fatty lining).

The epidermis is built from epithelial cells (epithermocytes) of various shapes and structures. Moreover, each overlying cell originates from the underlying one, reflecting a certain phase of its life.

The layers of the epidermis are arranged in the following sequence (from bottom to top):

• - basal (D) or embryonic;
• - a layer of spiny cells;
• - a layer of keratohyaline or granular cells;
• - epeidin or shiny;
• - horny.

In addition to epidermal cells, the epidermis (in the basal layer) contains cells capable of producing melanin (melanocytes), Lagerhans cells, Greenstein cells, etc.

The dermis is located directly under the epidermis and is separated from it by the main membrane. In the dermis, the papillary and reticular layers are distinguished. It consists of collagen, elastic and reticulin (argyrophilic) fibers, between which the main substance is located.

In the dermis, in fact, in the skin is the papillary layer, richly supplied with blood and lymphatic vessels. There are also plexuses of nerve fibers that give rise to numerous nerve endings in the epidermis and dermis. The dermis contains sweat and sebaceous glands, hair follicles at various levels.

Subcutaneous fat is the deepest layer of the skin.

The functions of the skin are complex and varied. The skin performs a barrier - protective, thermoregulatory, excretory, metabolic, receptor, etc.

The barrier-protective function, which is considered the most important function of the skin of humans and animals, is carried out through various mechanisms. Thus, the strong and elastic stratum corneum of the skin resists mechanical influences and reduces the harmful effects of chemicals. The stratum corneum, being a poor conductor, protects the deeper layers from drying out, cooling and the action of electric current.

Figure 2 - Skin structure

Sebum, a product of the secretion of sweat glands and scales of peeling epithelium, form an emulsion film (protective mantle) on the skin surface, which plays an important role in protecting the skin from the effects of chemical, biological and physical agents.

The acidic reaction of the water-lipid mantle and surface layers of the skin, as well as the bactericidal properties of the skin secretion, are an important barrier mechanism for microorganisms.

In protection from light rays, the pigment melanin plays a certain role.

The electrophysiological barrier is the main obstacle to the penetration of substances into the depths of the skin, including during electrophoresis. It is located at the level of the basal layer of the epidermis and is an electrical layer with heterogeneous layers. Due to the acidic reaction, the outer layer has a “+” charge, and the inward one “-”. it should be borne in mind that, on the one hand, the barrier-protective function of the skin weakens the effect of physical factors on the body, and on the other hand, physical factors can stimulate the protective properties of the skin and thereby realize a therapeutic effect.

Physical thermoregulation organism is also one of the most important physiological functions of the skin and is directly related to the mechanism of action of hydrotherapeutic factors. It is carried out by the skin by means of heat radiation in the form of infrared rays (44%) heat conduction (31%) and water evaporation from the skin surface (21%). It is important to note that the skin, with its thermoregulatory mechanisms, plays an important role in the acclimatization of the body.

Secret-excretory function the skin is associated with the activity of the sweat and sebaceous glands. It plays an important role in maintaining the homeostasis of the body, in the performance of the skin's barrier properties.

Respiratory and resorption function closely related. The respiratory function of the skin, consisting in the absorption of oxygen and the release of carbon dioxide, in the general balance of respiration for the body does not matter much. However, skin respiration can increase significantly in high air temperatures.

The resorption function of the skin, its permeability are of great importance not only in dermatology and toxicology. Its importance for physiotherapy is determined by the fact that the chemical component of the action of many therapeutic factors (medicinal, gas and mineral baths, mud therapy, etc.) depends on the penetration of their constituent ingredients through the skin.

Exchange function skin has specific features. On the one hand, only its inherent metabolic processes occur in the skin (the formation of keratin, melanin, vitamin D, etc.), on the other, it takes an active part in the general metabolism in the body. Its role is especially great in fat, mineral, carbohydrate and vitamin metabolism.

The skin is also a place of synthesis of biologically active substances (heparin, histamine, serotonin, etc.).

Receptor function the skin provides its connection with the external environment. The skin performs this function in the form of numerous conditioned and unconditioned reflexes due to the presence in it of the various receptors mentioned above.

It is considered that for 1 cm2 of skin there are 100-200 pain points 12-15 cold, 1-2 heat, 25 pressure points.

Relationship with internal organs is closely related - changes in the skin affect the activity of internal organs, and disturbances from the internal organs are accompanied by shifts in the skin. This relationship is especially clearly manifested in internal diseases in the form of the so-called reflexogenic, or painful, zones of Zakharin-Ged.

Zakharyin-Geda zone certain areas of the skin, in which, with diseases of internal organs, reflected pains often appear, as well as pain and temperature hyperesthesia.

Figure 3 - Location of the Zakharyin-Geda zone

Such zones in diseases of internal organs were also identified in the head area. For example, pain in frontal-nasal region corresponds to the defeat of the tops of the lungs, stomach, liver, aortic orifice.

Pain in the middle eye area damage to the lungs, heart, ascending aorta.

Pain in the frontotemporal region damage to the lungs, heart.

Pain in the parietal region damage to the pylorus and upper intestine, etc.

Comfort zone the area of ​​temperature conditions of the external environment, causing a subjectively good sensation of heat in a person without signs of cooling or overheating.

For a naked person 17.3 ° C - 21.7 ° C

For a dressed person 16.7 ° C - 20.6 ° C

Pulsed ultraviolet therapy

Research Institute of Power Engineering, Moscow State Technical University N.E.Baumana (Shashkovsky S.G. 2000) developed a portable device "Melitta 01" for local irradiation of the affected surfaces of skin coverings, mucous membranes with high-efficiency pulsed ultraviolet radiation of a continuous spectrum in the range of 230-380 nm.

The mode of operation of this unit is pulse-periodic with a frequency of 1 Hz. The device provides automatic generation of 1, 4, 8, 16, 32 pulses. Output pulse power density at a distance of 5 cm from the burner 25 W / cm2

Indications:

• - purulent-inflammatory diseases of the skin and subcutaneous tissue (furuncle, carbuncle, hydradenitis) in the initial period of hydration and after surgical opening of the purulent cavity;
• - extensive purulent wounds, wounds after necrectomy, wounds before and after autodermoplasty;
• - granulating wounds after thermal, chemical, radiation burns;
• - trophic ulcers and sluggish wounds;
• - erysipelas;
• - herpetic inflammation of the skin and mucous membranes;
• - irradiation of wounds before and after primary surgical treatment in order to prevent the development of purulent complications;
• - disinfection of indoor air, car interiors, buses and ambulances.

Pulse magnetic therapy with rotating field and variable pulse repetition rate automatically.

The known physical laws are the cornerstone of the curative action. An electric charge moving through a blood vessel in a magnetic field is affected by the Lorentz force perpendicular to the charge velocity vector, constant in a constant and alternating sign, in an alternating rotating magnetic field. This phenomenon is realized at all levels of the body (atomic, molecular, subcellular, cellular, tissue).

The action of low-intensity pulsed magnetic therapy has an active effect on deeply located muscle, nervous, bone tissue, internal organs, improving microcirculation, stimulating metabolic processes and regeneration. High-density electric currents, induced by a pulsed magnetic field, activate myelinated thick nerve fibers, as a result of which afferent impulses from the painful focus are blocked by the spinal mechanism of the "portal block". The pain syndrome is weakened or eliminated completely already during the procedure or after the first procedures. In terms of the severity of the analgesic effect, pulsed magnetic therapy is strongly superior to other types of magnetic therapy.

Thanks to pulsed rotating magnetic fields, it becomes possible to indicate in the depth of tissues without damaging them electric fields and currents of significant intensity. This makes it possible to obtain a pronounced therapeutic decongestant, analgesic, anti-inflammatory, stimulating regeneration, biostimulating effects of action, which, in terms of severity, are several times superior to the therapeutic effects obtained from all known devices of low-frequency magnetotherapy.

Pulsed magnetic therapy devices are a modern effective means of treating traumatic injuries, inflammatory, degenerative-dystrophic diseases of the nervous and musculoskeletal system.

Therapeutic effects of pulsed magnetic therapy: analgesic, decongestant, anti-inflammatory, vasoactive, stimulating regeneration processes in damaged tissues, neurostimulating, myostimulating.

Indications:

• - diseases and traumatic injuries of the central nervous system (cerebral ischemic stroke, transient cerebrovascular accident, consequences of traumatic brain injury with movement disorders, closed spinal cord injuries with motor impairments, cerebral palsy, functionally hysterical paralysis),
• - traumatic injuries of the musculoskeletal system (bruises of soft tissues, joints, bones, sprains, closed fractures of bones and joints during immobilization, in the stage of reparative regeneration, open fractures of bones, joints, soft tissue injuries during immobilization, in the stage of reparative regeneration, hypotrophy , muscle atrophy as a result of physical inactivity caused by traumatic injuries of the musculoskeletal system),
• - inflammatory degenerative-dystrophic injuries of the musculoskeletal system (deforming osteoarthritis of the joints with symptoms of synovitis and without symptoms of synovitis, widespread osteochondrosis, deforming spondylosis of the spine with symptoms of secondary radicular syndrome, cervical radiculitis with symptoms of scapular periapritis, radicular sciatica spondyloatritis, scoliotic disease in children),
• - surgical inflammatory diseases (postoperative period after surgical interventions on the musculoskeletal system, skin and subcutaneous tissue, sluggish wounds, trophic ulcers, boils, carbuncles, phlegmon after surgery, mastitis),
• - diseases of the bronchopulmonary system (bronchial asthma of mild and moderate severity, chronic bronchitis),
• - diseases of the digestive system (hypomotor and evacuation disorders of the stomach after stomach and vagotomy, hypomotor dysfunction of the colon, stomach and gallbladder, chronic hepatitis with moderate liver dysfunction, chronic pancreatitis with secretory insufficiency),
• - diseases of the cardiovascular system (occlusive lesions of peripheral arteries of atherosclerotic genesis),
• - urological diseases (stone in the ureter, condition after lithotripsy, atony of the bladder, weakness of the sphinker and detrusor, prostatitis),
• - gynecological diseases (inflammatory diseases of the uterus and appendages, diseases caused by ovarian hypofunction),
• - chronic prostatitis and sexual dysfunctions in men,
• - dental diseases (periodontal disease, filling pains).

Contraindications:

• - severe hypotension,
• - systemic blood diseases,
• - a tendency to bleeding,
• - thrombophlebitis,
• - thromboembolic disease, bone fractures before immobilization,
• - pregnancy,
• - thyrotoxicosis and nodular goiter,
• - abscess, phlegmon (before opening and drainage of cavities),
• - malignant neoplasms,
• - feverish condition,
• - cholelithiasis,
• - epilepsy.

A warning:

Pulse magnetic therapy should not be used in the presence of an implanted pacemaker, since the induced electrical potentials can disrupt its operation; with various metal objects freely lying in the tissues of the body (for example, fragments in case of wounds), if they are at a distance of less than 5 cm from the inductors, since objects made of electrically conductive materials (steel, copper, etc.) can move and cause damage to surrounding tissues. It is not allowed to affect the area of ​​the brain, heart and eyes.

Of great interest is the creation of low-intensity pulsed magnetic devices (20-150 mT) with a pulse repetition rate that approximately coincides with the frequency of the intrinsic biopotentials of organs (2-4-6-8-10-12 Hz). This would make it possible to exert a bioresonant effect on internal organs (liver, pancreas, stomach, lungs) with a pulsed magnetic field and positively influence their function. It is already known that UTI has a positive effect at a frequency of 8-10 Hz on liver function in patients with toxic (alcoholic) hepatitis.

The influence of the sun's light on a person can hardly be overestimated - under its action, the most important physiological and biochemical processes are triggered in the body. The solar spectrum is divided into infrared and visible parts, as well as the most biologically active ultraviolet part, which has a great impact on all living organisms on our planet. Ultraviolet radiation is a short-wavelength part of the solar spectrum that is imperceptible to the human eye, which has an electromagnetic character and photochemical activity.

Due to its properties, ultraviolet light is successfully used in various areas of human life. UV radiation is widely used in medicine, since it is capable of changing the chemical structure of cells and tissues, having various effects on humans.

UV wavelength range

The main source of UV radiation is the sun... The share of ultraviolet radiation in the total flow of sunlight is not constant. It depends on:

• time of day;
• season of the year;
• solar activity;
• geographical latitude;
• the state of the atmosphere.

Despite the fact that the celestial body is far from us and its activity is not always the same, a sufficient amount of ultraviolet radiation reaches the Earth's surface. But this is only its small long-wave part. Short waves are absorbed by the atmosphere at a distance of about 50 km from the surface of our planet.

The ultraviolet range of the spectrum that reaches the earth's surface is conventionally divided by wavelength into:

• far (400 - 315 nm) - UV - A rays;
• medium (315 - 280 nm) - UV - B rays;
• near (280 - 100 nm) - UV - C rays.

The effect of each UV range on the human body is different: the shorter the wavelength, the deeper it penetrates through the skin. This law determines the positive or negative effect of ultraviolet radiation on the human body.

Near-range UV radiation is the most harmful to health and carries the threat of serious illness.

UV - C rays should be scattered in the ozone layer, but due to poor ecology they reach the surface of the earth. Ultraviolet rays of the A and B range are less dangerous, with strict dosage, long and medium range radiation has a beneficial effect on the human body.

Artificial sources of ultraviolet radiation

The most significant sources of UV waves affecting the human body are:

• bactericidal lamps - sources of UV-C waves, are used to disinfect water, air or other objects of the external environment;
• industrial welding arc - sources of all waves in the solar spectrum;
• erythema fluorescent lamps - sources of UV A and B wavelengths used for therapeutic purposes and in tanning salons;
• industrial lamps are powerful sources of ultraviolet waves that are used in manufacturing processes to cure paints, inks, or cure polymers.

The characteristics of any UV lamp are its radiation power, wavelength range, glass type, and service life. It depends on these parameters how useful or harmful the lamp will be to humans.

Before irradiation with ultraviolet waves from artificial sources for the treatment or prevention of diseases, one should consult with a specialist to select the necessary and sufficient erythemal dose, which is individual for each person, taking into account his skin type, age, existing diseases.

It should be understood that ultraviolet is electromagnetic radiation, which has not only a positive effect on the human body.

A germicidal ultraviolet lamp used for tanning will bring significant harm rather than benefit to the body. Only a professional who is well versed in all the nuances of such devices should use artificial sources of UV radiation.

The positive effect of UV radiation on the human body

Ultraviolet radiation is widely used in the field of modern medicine. And this is not surprising, because UV rays produce analgesic, sedative, antirachitic and antispastic effects... Under their influence, there is:

• the formation of vitamin D, which is necessary for the absorption of calcium, the development and strengthening of bone tissue;
• lowering the excitability of nerve endings;
• increased metabolism, as it activates enzymes;
• vasodilation and improved blood circulation;
• stimulation of the production of endorphins - "hormones of happiness";
• an increase in the speed of regenerative processes.

The beneficial effect of ultraviolet waves on the human body is also expressed in a change in its immunobiological reactivity - the body's ability to exhibit protective functions against pathogens of various diseases. Severely dosed ultraviolet radiation stimulates the production of antibodies, thereby increasing the human body's resistance to infections.

Skin exposure to UV rays causes a reaction - erythema (redness)... There is an expansion of blood vessels, expressed by hyperemia and edema. The decay products formed in the skin (histamine and vitamin D) enter the bloodstream, which causes general changes in the body when exposed to UV waves.

The degree of development of erythema depends on:

• the magnitude of the ultraviolet dose;
• range of ultraviolet rays;
• individual sensitivity.

With excessive UV irradiation, the affected area of ​​the skin is very painful and swollen, a burn occurs with the appearance of a blister and further convergence of the epithelium.

But skin burns are far from the most serious consequences of prolonged exposure to ultraviolet radiation on a person. Unwise use of UV rays causes pathological changes in the body.

The negative effects of UV radiation on humans

Despite its important role in medicine, the harm of ultraviolet radiation on health outweighs the benefits... Most people are not able to accurately control the therapeutic dose of ultraviolet radiation and resort to protective methods in a timely manner, therefore, its overdose often occurs, which causes the following phenomena:

• headaches appear;
• body temperature rises;
• fatigue, apathy;
• memory impairment;
• cardiopalmus;
• decreased appetite and nausea.

Excessive sunburn affects the skin, eyes, and the immune (defense) system. The perceived and visible effects of excessive UV radiation (burns of the skin and mucous membranes of the eyes, dermatitis and allergic reactions) disappear within a few days. Ultraviolet radiation accumulates for a long time and causes very serious diseases.

The effect of ultraviolet radiation on the skin

A beautiful even tan is the dream of every person, especially the fairer sex. But it should be understood that skin cells darken under the influence of the coloring pigment released in them - melanin in order to protect against further ultraviolet irradiation. That's why sunburn is a protective reaction of our skin against damage to its cells by ultraviolet rays... But it does not protect the skin from the more serious effects of UV radiation:

1. Photosensitivity - increased sensitivity to ultraviolet light. Even a small dose of it causes severe burning, itching and sunburn of the skin. This is often associated with the use of medications or the use of cosmetics or certain foods.
2. Photoaging. UV-A rays penetrate into the deep layers of the skin, damage the structure of the connective tissue, which leads to the destruction of collagen, loss of elasticity, and early wrinkles.
3. Melanoma - skin cancer... The disease develops after frequent and prolonged exposure to the sun. Under the influence of an excessive dose of ultraviolet radiation, malignant formations appear on the skin or the degeneration of old moles into a cancerous tumor.
4. Basal cell and squamous carcinoma is a non-melanoma skin cancer that is not fatal, but requires surgical removal of the affected areas. It is noticed that the disease occurs much more often in people who work under the open sun for a long time.

Any dermatitis or sensitization of the skin under the influence of ultraviolet radiation are provoking factors for the development of skin cancer.

Effect of UV waves on the eyes

Ultraviolet rays, depending on the depth of penetration, can negatively affect the condition of the human eyes:

1. Photophthalmia and electrophthalmia. It is expressed in redness and swelling of the mucous membrane of the eyes, lacrimation, photophobia. Occurs when safety rules are not followed when working with welding equipment or people who are in bright sunlight in a snow-covered area (snow blindness).
2. Overgrowth of the conjunctiva of the eye (pterygium).
3. Cataract (clouding of the lens of the eye) is a disease that occurs to varying degrees in the vast majority of people towards old age. Its development is associated with exposure to ultraviolet radiation on the eyes, which accumulates throughout life.

Excess UV rays can lead to various forms of eye and eyelid cancers.

The effect of ultraviolet radiation on the immune system

If the dosed use of UV radiation helps to increase the body's defenses, then excessive exposure to ultraviolet radiation suppresses the immune system... This has been proven in scientific research by US scientists on the herpes virus. Ultraviolet radiation changes the activity of cells responsible for immunity in the body, they cannot restrain the multiplication of viruses or bacteria, cancer cells.

Basic safety measures and protection against exposure to ultraviolet radiation

To avoid the negative effects of UV rays on the skin, eyes and health, everyone needs protection from ultraviolet radiation. In case of forced prolonged exposure to the sun or at a workplace exposed to high doses of ultraviolet rays, it is imperative to find out if the UV radiation index is normal. In enterprises, a device called a radiometer is used for this.

When calculating the index at meteorological stations, the following is taken into account:

• ultraviolet wavelength;
• concentration of the ozone layer;
• sun activity and other indicators.

The UV index is an indicator of the potential risk to the human body as a result of exposure to a dose of ultraviolet radiation. The index value is assessed on a scale from 1 to 11+. The norm of the UV index is considered to be no more than 2 units.

At high values ​​of the index (6 - 11+), the risk of adverse effects on human eyes and skin increases, therefore protective measures must be taken.

1. Use sunglasses (special masks for welders).
2. Be sure to wear a hat in the open sun (with a very high index - a wide-brimmed hat).
3. Wear clothing that covers your arms and legs.
4. On uncovered areas of the body apply sunscreen with a protection factor of at least 30.
5. Avoid being in an open, not protected from sunlight, space between noon and 4 pm.

Fulfillment of simple safety rules will reduce the harmfulness of UV radiation for humans and avoid the occurrence of diseases associated with the adverse effect of ultraviolet radiation on his body.

Who is contraindicated for ultraviolet irradiation?

The following categories of people should be careful with exposure to ultraviolet radiation:

• with very light and sensitive skin and albinos;
• children and adolescents;
• those who have many birthmarks or nevi;
• suffering from systemic or gynecological diseases;
• those who have skin cancer among their close relatives;
• taking certain medications for a long time (consultation with a doctor is necessary).

UV radiation for such people is contraindicated even in small doses, the degree of protection from sunlight should be maximized.

The effect of ultraviolet radiation on the human body and its health cannot be unequivocally called positive or negative. Too many factors should be taken into account when it is exposed to a person in different environmental conditions and when it is emitted from different sources. The main thing is to remember the rule: any exposure to ultraviolet radiation on a person should be minimal before consulting a specialist and strictly dosed according to the doctor's recommendations after examination and examination.

The concept of ultraviolet rays was first encountered by a 13th century Indian philosopher in his work. The atmosphere of the area he described Bhootakasha contained violet rays that cannot be seen with the naked eye.

Soon after the discovery of infrared radiation, German physicist Johann Wilhelm Ritter began looking for radiation at the opposite end of the spectrum, with a wavelength shorter than that of violet. In 1801, he discovered that silver chloride, decomposed by light, was faster decomposes under the influence of invisible radiation outside the violet region of the spectrum. Silver chloride, white in color, darkens in the light within a few minutes. Different parts of the spectrum have different effects on the rate of darkening. This occurs most rapidly in front of the violet region of the spectrum. It was then that many scientists, including Ritter, agreed that light is made up of three separate components: an oxidizing or thermal (infrared) component, an illuminating component (visible light), and a reducing (ultraviolet) component. At that time, ultraviolet radiation was also called actinic radiation. The ideas about the unity of three different parts of the spectrum were first voiced only in 1842 in the works of Alexander Becquerel, Macedonio Melloni, and others.

Subtypes

Degradation of polymers and dyes

Scope of application

Black light

Chemical analysis

UV spectrometry

UV spectrophotometry is based on the irradiation of a substance with monochromatic UV radiation, the wavelength of which changes over time. The substance absorbs UV radiation at different wavelengths to varying degrees. The graph, the ordinate of which is the amount of transmitted or reflected radiation, and the abscissa is the wavelength, forms a spectrum. Spectra are unique for each substance, which is the basis for the identification of individual substances in a mixture, as well as their quantitative measurement.

Mineral analysis

Many minerals contain substances that, when illuminated with ultraviolet light, begin to emit visible light. Each impurity glows in its own way, which makes it possible to determine the composition of a given mineral by the nature of the glow. AA Malakhov in his book "Interestingly about geology" (Moscow, "Molodaya gvardiya", 1969, 240 p.) Tells about it this way: "The unusual glow of minerals is caused by cathode, ultraviolet, and X-rays. In the world of dead stone, those minerals that light up and shine most brightly, which, once in the ultraviolet light zone, tell about the smallest impurities of uranium or manganese included in the composition of the rock. Many other minerals, which do not contain any impurities, flash with a strange "unearthly" color. I spent the whole day in the laboratory, where I observed the luminescent glow of minerals. Plain colorless calcite was colored wonderfully under the influence of various light sources. The cathode rays made the crystal ruby-red; in ultraviolet light, it lit up with crimson-red tones. Two minerals - fluorite and zircon - did not differ in X-rays. Both were green. But as soon as the cathode light was connected, the fluorite turned violet, and the zircon turned lemon yellow. " (p. 11).

Qualitative chromatographic analysis

Chromatograms obtained by TLC are often viewed in ultraviolet light, which makes it possible to identify a number of organic substances by their luminescence color and retention index.

Catching insects

Ultraviolet radiation is often used to catch insects by light (often in combination with lamps emitting in the visible part of the spectrum). This is due to the fact that in most insects, the visible range is shifted, compared to human vision, to the shortwave part of the spectrum: insects do not see what a person perceives as red, but they see soft ultraviolet light.

Artificial tan and "Mountain sun"

At certain dosages, artificial tanning improves the condition and appearance of human skin, promotes the formation of vitamin D. Currently, photoaria are popular, which are often called solariums in everyday life.

Ultraviolet in restoration

One of the experts' main tools is ultraviolet, X-ray and infrared radiation. Ultraviolet rays allow you to determine the aging of the varnish film - a fresher varnish looks darker in ultraviolet light. In the light of a large laboratory ultraviolet lamp, the restored areas and artisanally rewritten signatures appear darker spots. X-rays are trapped by the heaviest elements. In the human body, this is bone tissue, but in the picture it is white. In most cases, white is based on lead, in the 19th century zinc began to be used, and in the 20th century - titanium. These are all heavy metals. Ultimately, on film, we get an image of a whitewash underpainting. Underpainting is the artist's individual “handwriting”, an element of his own unique technique. To analyze the underpainting, the bases of the radiographs of the paintings of the great masters are used. Also, these pictures are used to recognize the authenticity of the painting.

Notes (edit)

1. ISO 21348 Process for Determining Solar Irradiances. Archived from the original on June 23, 2012.
2. Bobukh, Eugene About the eyesight of animals. Archived from the original on November 7, 2012. Retrieved November 6, 2012.
3. Soviet encyclopedia
4. V.K.Popov // UFN... - 1985. - T. 147. - S. 587-604.
5. A.K.Shuaibov, V.S.Shevera Ultraviolet nitrogen laser at 337.1 nm in high repetition mode // Ukrainian physics journal... - 1977. - T. 22. - No. 1. - S. 157-158.
6. A. G. Molchanov

Ultraviolet radiation is electromagnetic waves with a length of 180 to 400 nm. This physical factor has many positive effects on the human body and is successfully used to treat a number of diseases. In this article, we will talk about what these effects are, about the indications and contraindications to the use of ultraviolet radiation, as well as about the devices used and procedures.

Ultraviolet rays penetrate the skin to a depth of 1 mm and cause many biochemical changes in it. Distinguish between long-wave (region A - the wavelength is from 320 to 400 nm), medium-wave (region B - the wavelength is 275-320 nm) and short-wave (region C - the wavelength is in the range from 180 to 275 nm) ultraviolet radiation. It should be noted that different types of radiation (A, B or C) affect the body in different ways, therefore, they should be considered separately.

Long wavelength radiation

One of the main effects of this type of radiation is pigmenting: falling on the skin, the rays stimulate the occurrence of certain chemical reactions, as a result of which the pigment melanin is formed. Granules of this substance are secreted into the skin cells and cause a tan. The maximum amount of melanin in the skin is determined 48-72 hours after exposure.

The second important effect of this method of physiotherapy is immunostimulating: the products of photodestruction bind to skin proteins and induce a chain of biochemical transformations in cells. The result of this is the formation of an immune response after 1-2 days, that is, local immunity and nonspecific resistance of the body to a variety of unfavorable environmental factors increase.

The third effect of ultraviolet radiation is photosensitizing. A number of substances have the ability to increase the sensitivity of the skin of patients to the effects of this type of radiation and stimulate the formation of melanin. That is, taking such a drug and subsequent ultraviolet irradiation will lead to skin swelling and reddening (erythema) in persons suffering from dermatological diseases. The result of this course of treatment will be the normalization of skin pigmentation and structure. This method of treatment is called "photochemotherapy".

Of the negative effects of excessive long-wave ultraviolet radiation, it is important to mention the inhibition of antitumor reactions, that is, an increase in the likelihood of developing a tumor process, in particular, melanoma - skin cancer.

Indications and contraindications

The indications for treatment with long-wave ultraviolet radiation are:

• chronic inflammatory processes in the respiratory system;
• diseases of the osteoarticular apparatus of an inflammatory nature;
• frostbite;
• burns;
• skin diseases - psoriasis, fungal mycosis, vitiligo, seborrhea and others;
• poorly treatable wounds;
• trophic ulcers.

For some diseases, the use of this method of physiotherapy is not recommended. Contraindications are:

• acute inflammatory processes in the body;
• severe chronic renal and hepatic failure;
• individual hypersensitivity to ultraviolet light.

Devices

Sources of UV rays are divided into integral and selective. Integral ones emit UV rays of all three spectra, and selective ones - only region A or regions B + C. As a rule, in medicine, selective radiation is used, which is obtained using the LUF-153 lamp in the UUD-1 and 1A irradiators, OUG-1 (for the head), OUK-1 (for the limbs), EGD-5, EOD-10, PUVA , Psorymox and others. Also, long-wave UV radiation is used in tanning salons designed to obtain an even tan.

This type of radiation can affect the entire body at once or any part of it.

If the patient is to be exposed to general radiation, he should undress and sit quietly for 5-10 minutes. No creams or ointments should be applied to the skin. The entire body is exposed at once or its parts in turn - it depends on the type of installation.

The patient is at least 12-15 cm away from the device, and his eyes are protected by special glasses. The duration of irradiation directly depends on the type of skin pigmentation - there is a table with irradiation schemes depending on this indicator. The minimum exposure time is 15 minutes, and the maximum is half an hour.

Medium-wave ultraviolet radiation

This type of UV radiation has the following effects on the human body:

• immunomodulatory (in suberythemal doses);
• vitamin-forming (promotes the formation of vitamin D 3 in the body, improves the absorption of vitamin C, optimizes the synthesis of vitamin A, stimulates metabolism);
• anesthetic;
• anti-inflammatory;
• desensitizing (the body's sensitivity to the products of photodegradation of proteins decreases - in erythemal doses);
• tropho-stimulating (stimulates a number of biochemical processes in cells, as a result of which the number of functioning capillaries and arterioles increases, blood flow in tissues improves - erythema is formed).

Indications and contraindications

Indications for the use of medium-wave ultraviolet radiation are:

• inflammatory diseases of the respiratory system;
• post-traumatic changes in the musculoskeletal system;
• inflammatory diseases of bones and joints (arthritis, arthrosis);
• vertebral radiculopathy, neuralgia, myositis, plexitis;
• solar starvation;
• metabolic diseases;
• erysipelas.

Contraindications are:

• individual hypersensitivity to UV rays;
• hyperfunction of the thyroid gland;
• chronic renal failure;
• systemic connective tissue diseases;
• malaria.

Devices

Sources of radiation of this type, like the previous one, are divided into integral and selective.

Integral sources are DRT lamps of various power, which are installed in the OKN-11M (quartz tabletop), ORK-21M (mercury-quartz), UGN-1 (for group nasopharyngeal irradiation), OUN 250 (tabletop) irradiators. Another type of lamps - DRK-120 is intended for cavity irradiators OUP-1 and OUP-2.

A selective source is an LZ 153 fluorescent lamp for OUSH-1 (on a tripod) and OUN-2 (tabletop) irradiators. Erythema lamps LE-15 and LE-30, made of glass that transmits UV rays, are also used in wall-mounted, suspended and mobile irradiators.

Ultraviolet radiation is dosed, as a rule, by a biological method, which is based on the ability of UV rays to cause reddening of the skin after irradiation - erythema. The unit of measurement is 1 biodose (the minimum time of ultraviolet irradiation of the patient's skin on any part of his body, causing the appearance of the least intense erythema during the day). Gorbachev's biodosimeter looks like a metal plate on which there are 6 rectangular holes that are closed by a shutter. The device is fixed on the patient's body, UV radiation is directed at him and every 10 seconds, 1 window of the plate is opened in turn. It turns out that the skin under the first hole is exposed to radiation for 1 minute, and under the last - only 10 seconds. After 12-24 hours, a threshold erythema occurs, which determines the biodose - the time of exposure to UV radiation on the skin under this opening.

There are the following types of doses:

• suberythemal (0.5 biodoses);
• small erythemal (1-2 biodoses);
• medium (3-4 biodoses);
• high (5-8 biodoses);
• hypererythemal (more than 8 biodoses).

Procedure technique

There are 2 methods - local and general.

Local exposure is carried out on a skin area, the area of ​​which does not exceed 600 cm 2. As a rule, erythemal doses of radiation are used.

The procedure is carried out 1 time in 2-3 days, each time increasing the dose by 1 / 4-1 / 2 from the previous one. One area can be exposed no more than 3-4 times. A repeated course of treatment is recommended to the patient after 1 month.

With the general exposure, the patient is in the supine position; the surface of his body is irradiated in turn. There are 3 treatment regimens - basic, accelerated and delayed, according to which, depending on the procedure number, the biodose is determined. The course of treatment is up to 25 exposures and can be repeated in 2-3 months.

Electrophthalmia

This term is called the negative impact of medium-wave spectrum radiation on the organ of vision, which consists in damage to its structures. This effect can occur when observing the sun without using protective devices, while staying in a snowy area or in very bright, sunny weather at sea, as well as during quartzing of premises.

The essence of electrophthalmia is a corneal burn, which is manifested by pronounced lacrimation, redness and cutting pain in the eyes, photophobia and corneal edema.

Fortunately, in the vast majority of cases, this condition is short-lived - as soon as the epithelium of the eye heals, its functions will be restored.

To alleviate your condition or the condition of people around you with electrophthalmia, you should:

• rinse your eyes with clean, preferably running water;
• drip moisturizing drops into them (drugs such as artificial tears);
• wear safety glasses;
• if the patient complains of cramps in the eyes, you can relieve his suffering with the help of compresses from grated raw potatoes or black tea bags;
• if the above measures did not give the desired effect, you should seek help from a specialist.

Shortwave radiation

It has the following effects on the human body:

• bactericidal and fungicidal (stimulates a number of reactions, as a result of which the structure of bacteria and fungi is destroyed);
• detoxification (under the influence of UV radiation, substances appear in the blood that neutralize toxins);
• metabolic (during the procedure, microcirculation improves, as a result of which organs and tissues receive more oxygen);
• correcting blood clotting ability (with UV irradiation of blood, the ability of erythrocytes and platelets to form blood clots changes, coagulation processes are normalized).

Indications and contraindications

The use of short-wave ultraviolet radiation is effective in the following diseases:

• skin diseases (psoriasis, neurodermatitis);
• erysipelas;
• rhinitis, tonsillitis;
• otitis media;
• wounds;
• lupus;
• abscesses, boils, carbuncles;
• osteomyelitis;
• rheumatic heart valve disease;
• essential hypertension I-II;
• acute and chronic respiratory diseases;
• diseases of the digestive system (peptic ulcer and duodenal ulcer, gastritis with high acidity);
• diabetes;
• long-term non-healing ulcers;
• chronic pyelonephritis;
• acute adnexitis.

A contraindication to this type of treatment is individual hypersensitivity to UV rays. Blood irradiation is contraindicated in the following diseases:

• mental illness;
• chronic renal and hepatic failure;
• porphyria;
• thrombocytopenia;
• callous ulcer of the stomach and duodenum;
• decreased blood clotting ability;
• strokes;
• myocardial infarction.

Devices

Integral radiation sources - DRK-120 lamp for cavity irradiators OUP-1 and OUP-2, DRT-4 lamp for nasopharynx irradiator.

Selective sources are DB germicidal lamps of various power - from 15 to 60 W. They are installed in the OBN, OBSH, OBP irradiators.

For the purpose of carrying out autotransfusion with ultraviolet irradiated blood, the apparatus MD-73M "Isolde" is used. The source of radiation in it is the LB-8 lamp. There is a possibility to regulate the dose and the area of ​​irradiation.

Procedure technique

The affected areas of the skin and mucous membranes are exposed to general UV irradiation schemes.

With diseases of the nasal mucosa, the patient is in a sitting position on a chair, his head slightly thrown back. The emitter is introduced at a shallow depth alternately into both nostrils.

A special mirror is used to irradiate the tonsils. Reflecting from it, the rays are directed to the left and right tonsils. The patient's tongue is sticking out, he holds it with a gauze napkin.

The effects are dosed by determining the biodose. In acute conditions, start with 1 biodose, gradually increasing it to 3. You can repeat the course of treatment after 1 month.

The blood is irradiated for 10-15 minutes during 7-9 procedures with a possible repetition of the course in 3-6 months.

The sun is a powerful source of heat and light. Without it, there can be no life on the planet. The sun emits rays that are invisible to the naked eye. We will find out what properties ultraviolet radiation has, its effect on the body and possible harm.

The solar spectrum has infrared, visible and ultraviolet parts. UV has both positive and negative effects on humans. It is used in various spheres of life. Widespread use is noted in medicine, ultraviolet radiation has the ability to change the biological structure of cells, affecting the body.

Radiation sources

The main source of ultraviolet rays is the sun. They are also obtained using special bulbs:

1. High pressure mercury-quartz.
2. Vital luminescent.
3. Ozone and quartz bactericidal.

Currently, only a few types of bacteria are known to mankind that can exist without ultraviolet radiation. For other living cells, its absence will lead to death.

What is the effect of ultraviolet radiation on the human body?

Positive action

Today, UV is widely used in medicine. It has a calming, analgesic, antirachitic and antispastic effect. The positive effect of ultraviolet rays on the human body:

• intake of vitamin D, it is needed for the absorption of calcium;
• improvement of metabolism, as enzymes are activated;
• decrease in nervous tension;
• increased production of endorphins;
• vasodilation and normalization of blood circulation;
• acceleration of regeneration.

Ultraviolet for humans is also useful in that it affects the immunobiological activity, helps to activate the body's protective functions against various infections. At a certain concentration, radiation causes the production of antibodies that affect pathogens.

Bad influence

The harm of an ultraviolet lamp to the human body often exceeds its beneficial properties. If its use for medicinal purposes is performed incorrectly, safety measures were not followed, an overdose is possible, characterized by the following symptoms:

1. Weakness.
2. Apathy.
3. Decreased appetite.
4. Memory problems.
5. Cardiopalmus.

Prolonged exposure to the sun is harmful to the skin, eyes and immunity. The consequences of excessive sunburn, such as burns, dermatological and allergic rashes, disappear after a few days. Ultraviolet radiation slowly accumulates in the body and causes dangerous diseases.

Skin exposure to UV can cause erythema. The vessels dilate, which is characterized by hyperemia and edema. The accumulated histamine and vitamin D on the body are released into the bloodstream, which contributes to changes in the body.

The stage of development of erythema depends on:

• range of UV rays;
• radiation dose;
• individual sensitivity.

Excessive radiation causes a burn on the skin with the formation of a blister and subsequent convergence of the epithelium.

But the harm of ultraviolet radiation is not limited to burns, its irrational use can provoke pathological changes in the body.

UV action on skin

Most girls strive for a beautiful tanned body. However, the skin gets a dark color under the influence of melanin, so the body is protected from further radiation. But it will not protect you from more serious exposure to radiation:

1. Photosensitivity - high sensitivity to ultraviolet light. Its minimal effect can provoke a burning sensation, itching or burns. This is mainly due to the use of drugs, cosmetics, or certain foods.
2. Aging - UV rays penetrate into the deep layers of the skin, destroy collagen fibers, lose elasticity and wrinkles appear.
3. Melanoma is skin cancer that results from frequent and prolonged exposure to the sun. An excessive dose of ultraviolet radiation causes the development of malignant neoplasms on the body.
4. Basal cell carcinoma and squamous carcinoma are cancers on the body that require surgical removal of the affected areas. Often this ailment occurs in people whose work involves long exposure to the sun.

Any skin dermatitis caused by UV rays can cause skin cancers.

Effect of UV on the eyes

Ultraviolet light can also be harmful to the eyes. As a result of its influence, the development of the following diseases is possible:

• Photophthalmia and electrophthalmia. It is characterized by redness and swelling of the eyes, lacrimation, photophobia. Appears in those who are often in the bright sun in snowy weather without sunglasses or welders who do not follow safety rules.
• Cataract is a clouding of the lens. This disease mainly appears in old age. It develops as a result of the action of the sun's rays on the eyes, which accumulates throughout life.
• Pterygium is an enlargement of the conjunctiva of the eye.

Some types of cancers on the eyes and eyelids are also possible.

How does UV affect the immune system?

How does radiation affect immunity? In a certain dose, UV rays increase the body's protective functions, but their excessive action weakens the immune system.

Radiation radiation changes the protective cells, and they lose their ability to fight various viruses, cancer cells.

Skin protection

To protect yourself from the sun's rays, you must follow certain rules:

1. You need to stay in the open sun in moderation, a small tan has a photoprotective effect.
2. It is necessary to enrich the diet with antioxidants and vitamins C and E.
3. Always use sunscreen. In this case, you need to choose a product with a high level of protection.
4. It is allowed to use ultraviolet light for medicinal purposes only under the supervision of a specialist.
5. Those working with UV sources are advised to protect themselves with a mask. This is necessary when using a germicidal lamp, which is dangerous to the eyes.
6. Lovers of an even tan should not visit the solarium too often.

You can also use special clothing to protect yourself from radiation.

Contraindications

The following people should not be exposed to ultraviolet light:

• those who have too light and sensitive skin;
• with an active form of tuberculosis;
• children;
• with acute inflammatory or oncological diseases;
• albinos;
• during the II and III stages of hypertension;
• with a large number of moles;
• those who suffer from systemic or gynecological ailments;
• with prolonged use of certain medications;
• with a hereditary predisposition to skin cancer.

Infrared radiation

Another part of the solar spectrum is infrared radiation, which has a thermal effect. It is used in modern saunas.

Is a small wooden room with built-in infrared emitters. Under the influence of their waves, the human body heats up.

The air in an infrared sauna does not rise above 60 degrees. However, the rays heat the body up to 4 cm, when in a traditional bath the heat penetrates only 5 mm.

This is because the infrared wavelength is the same length as the heat wave coming from a person. The body accepts them as its own and does not resist penetration. The human body temperature rises to 38.5 degrees. Thanks to this, viruses and dangerous microorganisms die. The infrared sauna has a healing, rejuvenating and preventive effect. It is indicated for all ages.

Before visiting such a sauna, it is necessary to consult with a specialist, and also follow the safety precautions of being in a room with infrared emitters.

Video: ultraviolet.

UV in medicine

In medicine, there is the term "ultraviolet starvation". This happens when the body lacks sufficient sunlight. So that no pathologies arise from this, artificial sources of ultraviolet radiation are used. They help fight winter vitamin D deficiencies and boost immunity.

Also, such radiation is used in the treatment of joints, allergic and dermatological diseases.

In addition, UV has the following medicinal properties:

1. Normalizes the thyroid gland.
2. Improves the function of the respiratory and endocrine systems.
3. Increases hemoglobin.
4. Disinfects premises and medical instruments.
5. Reduces sugar levels.
6. Helps in the treatment of purulent wounds.

It should be borne in mind that an ultraviolet lamp is not always a benefit, and great harm is possible.

In order for UV radiation to have a beneficial effect on the body, you must use it correctly, observe safety precautions and do not exceed the time spent in the sun. Excessive excess of the radiation dose is dangerous for human health and life.