Background: Electromagnetic radiation has become an extensive new pollution source in modern civilization. Therefore, the biological effects of electromagnetic radiation have attracted considerable attention worldwide. Objectives: The current review was aimed to highlight on sources of electromagnetic fields and their effects on vital organs and the risk of cancer. Electromagnetic sources can be classified into natural electromagnetic sources (sun, some distant stars, atmospheric discharges like thunder, or human body) and unnatural or human made sources (printers, vacuum cleaners, cellular phones, hair dryers, refrigerators, washing machines, kettles microwaves, cables that carry electrical currents, television and computers, electrical home gadgets, radio and television base stations, mobile phone base stations and phone equipment), home wiring airport, and transformers. Electromagnetic fields (EMFs) are electromagnetic waves less than 300 GHz, that are divided into extremely low frequencies (ELFs; 3–3,000 Hz), involving high-voltage transmission lines and in-house wiring; and radiofrequencies (RFs; 30 kHz to 300 GHz), involving mobile phones, smart devices, base stations, WiFi, and 5G technologies. Cell phone technology is an integral part of everyday life and its use is not only restricted to voice conversations but also conveying news, high-resolution pictures, and the internet. Exposure to electromagnetic fields might produce oxidative stress, sperm damage, DNA damage, changes in the chromatin conformation, formation of micronucleus in different cell types, gene expression, enzyme activity, and changes in the structure and function of cell membrane, stimulated an increase in apoptosis and biosynthesis of plasma metallothionein and corticosterone. It causes headaches, chronic fatigue, heart problems, stress, nausea, chest pain, gastrointestinal issues, pain in the muscles and joints, sweating, neurocognitive disturbances, eye burning, nose, ear, and throat issues, bad effects on reproductive, central nervous, endocrine, cardiovascular, and immune systems. Also, it increases anxiety-related behavior; spatial memory, and learning deficits in male mice offspring, decreased thermal pain perception, induced a sleep disturbance, latency, and day dysfunction especially in females, a change in memory performance, damage to the lens epithelial cells of rabbits after 8 hours of exposure to microwave radiation, produced lens opacity in rats, which is linked to the production of cataracts, and derangement of chicken embryo retinal differentiation. There are a relationship between exposure to electromagnetic fields and the increased incidence of the occurrence of some tumors types, particularly brain cancer and leukemia. EMFs induce damage of tissues by increasing free radicals and changing the antioxidant defense systems of tissues, eventually leading to oxidative stress which leads to behavioral, histopathological and biochemical alterations. Exposure to radar, which uses RF fields above 6 GHz similar to 5 G causes effects on production of cancer at different sites, and other diseases. The possible mechanism proposed of how EMFs lead to cancer is the impact of EMFs on free radical combination rates in certain enzymes, such as coenzyme B12-dependent ethanolamine ammonia lyase. The enzyme reaction rate may be amplified by a factor of up to 100. A case-control studies found an increased risk of gliomas, acoustic neuromas, and temporal lobe tumours in users with highest self-reported cell phone use. Exposure of experimental animals to microwave radiation caused a decrease in learning and memory ability, abnormal hippocampal morphology and abnormal Electroencephalogram. Also, it could lead to a decrease in norepinephrine and epinephrine contents in the brain, leading to neurotransmitter production disorders. Conclusion: It can be concluded that electromagnetic sources classified into natural electromagnetic and human made sources. EMFs) are electromagnetic waves less than 300 GHz are divided into extremely low frequencies and radiofrequencies. Exposure to electromagnetic fields might produce oxidative stress, which leads to histopathological and biochemical alterations in different body organs and increased risk of gliomas, acoustic neuromas, and temporal lobe tumours in users with highest self-reported cell phone use. Further studies are needed to confirm these effects in human and experimental animals.
Read full abstract