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Lecture No. 21
Electromagnetic field (EMF) radio frequency is characterized by the ability to heat materials; propagate in space and reflect from the interface between two media; interact with matter, due to which electromagnetic fields are widely used in various sectors of the national economy: industry, science, technology, medicine, everyday life.
Electromagnetic waves are partially absorbed by the tissues of a biological object, so the biological effect depends on the physical parameters of the RF EMF:
1) wavelength;
2) intensity and mode of radiation;
3) the duration and nature of exposure of the body;
4) on the area of the irradiated surface and the anatomical structure of the organ and tissue.
When an EMF acts on a biological object, the electromagnetic energy of the external field is converted into thermal energy, which is accompanied by an increase in body temperature or local selective heating of tissues, cell organs, especially with poor thermoregulation (the lens, the vitreous body, etc.). the thermal effect depends on the intensity of irradiation.
The effect of electromagnetic fields of radio frequencies on the central nervous system at an energy flux density (EFE) of more than 1 m W/cm2 indicates its high sensitivity to electromagnetic radiation.
A change in the blood is observed, as a rule, with PES above 10 mW / cm3, at lower exposure levels, phase changes in the number of leukocytes, erythrocytes and hemoglobin are observed.
With prolonged exposure to EMF, physiological adaptation or weakening of immunological reactions occur.
Static electricity - this is a set of phenomena associated with the emergence, conservation and relaxation of a free electric charge on the surface and in the volume of dielectric and semiconductor substances, materials, products or on insulated conductors.
Studies of biological effects have shown that the nervous, cardiovascular, neurohumoral and other systems of the body are most sensitive to electrostatic fields.
Optical quantum generator is a generator of electromagnetic radiation in the optical range, based on the use of stimulated (stimulated) radiation.
The effect of lasers on the body depends on the radiation parameters, exposure localization and anatomy. The energy of laser radiation in biological objects (tissues, organs) can undergo various transformations and cause organic changes in the irradiated tissues (primary effects) and post-mortem functional changes (secondary effects). In this case, a combined thermal and mechanical effect on the irradiated structures is observed.
Biological action of UV - Rays of sunlight is manifested primarily in their positive effect on the human body. The most common consequences of lack of sunlight are beriberi, weakening of the protective immunobiological reactions of the body, exacerbation of chronic diseases, and functional disorders of the nervous system.
UV radiation from industrial sources can cause acute and chronic diseases.
Authors: Alekseev V.S., Zhidkova O.I., Tkachenko I.V.
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