Jul 26, · I introduce myself as a master’s student, my field of study in physics, and I work in environmental pollution. I have two research papers and I want to 4. The human activity, among the following, which causes maximum environmental pollution having regional and global impacts, is: (a) Urbanization (b) Industrialisation (c) Agriculture (d) Mining. 5. Production, transformation and use of energy are the major problems of: (a) Industrial activity (b) Sustainable development (c) Global warming (d Environmental Research Letters covers all of environmental science, providing a coherent and integrated approach including research articles, perspectives and review articles. Transparent peer review articles. Submit an article opens in new tab Track my article opens in new tab. RSS. Sign up for new issue notifications
Possible Effects of Radiofrequency Electromagnetic Field Exposure on Central Nerve System
Try out PMC Labs and tell us what you think. Learn More. Technological advances of mankind, through the development of electrical and communication technologies, have resulted in the exposure to artificial electromagnetic fields EMF. Technological growth is expected to continue; as such, the amount of EMF exposure will continue to increase steadily. In particular, the use-time of smart phones, that have become a necessity for modern people, is steadily increasing.
Social concerns and interest in the impact on the cranial nervous system are increased when considering the area where the mobile phone is used. However, before discussing possible effects of radiofrequency-electromagnetic field RF-EMF on the human body, several factors must be investigated about the influence of EMFs at the level of research using in vitro or animal models.
Scientific studies on the mechanism of biological effects are also required. It has been found that RF-EMF can induce changes in central nervous system nerve cells, including neuronal cell apoptosis, changes in the function of the nerve myelin and ion channels; furthermore, RF-EMF act as a stress source in living creatures.
The possible biological effects of RF-EMF exposure have not yet been proven, and there are insufficient data on biological hazards to provide a clear answer to possible health risks. Therefore, it is necessary to study the biological response to RF-EMF in consideration of the comprehensive exposure with regard to the use of various devices by individuals. In this various human activities and environmental effects research papers, we summarize the possible biological effects of RF-EMF exposure.
There is a constant geomagnetic field on the surface of the planet as solar wind generated from the sun meets with the inside of the earth. Therefore, all life on Earth is always living in the presence of an electromagnetic field EMF Hollenbach and Herndon, With the development of science and technology, artificial electromagnetic waves have been generated on Earth, and the German physicist Heinrich Hertz experimentally discovered electromagnetic radiation and confirmed the existence of the EMF in the ecosystem.
With the progress of science and technology, many electronic devices have various human activities and environmental effects research papers invented and used, therefore, we have easily been exposed to the created artificial electromagnetic waves in our daily life.
Especially, explosive use of various electronic devices in modern society has inevitably led to increase continuously the chances of electromagnetic wave exposure. The development of wireless communication technologies, such as computers and smartphones, have become a necessity for modern people. As a consequence, all living things on Earth are experiencing environmental changes and are being exposed to artificial electromagnetic waves which have not been experienced before.
The effect of electromagnetic waves on living creatures has been controversial due to studies with contradicting results. Considering the fact that most people, including young children, use mobile phones in Korea, the possibility of exposure to a considerable amount of electromagnetic waves exists all around us, therefore social interest in the impact on RF-EMF exposure has been greatly increased Langer et al.
There are many controversies regarding RF-EMF exposure, but many of the studies have focused on cancer Morgan et al. However, the possible biological effects of exposure to RF-EMF have not yet been proven and there are insufficient data on the biological hazards to provide a clear answer to possible health risks. Thus, the vague fear for the many unknown effects of RF-EMF exposure is expressed as ungrounded negative effects not only to the scientific community but also to the general public.
In addition to this, scientific data published by various researchers have been contradictory in their outcome. In particular, detailed information regarding the mechanism of biological effect by RF-EMFs has not yet been elucidated clearly.
Recent studies show that RF-EMFs emitted by cellular phones are absorbed into the brain, various human activities and environmental effects research papers, to a degree, that can affect neuronal activity Kleinlogel et al.
In addition, the thermal effects of RF-EMFs suggest the possibility of affecting neuronal activity by temperature generated by mobile phones Wainwright, ; Wyde et al. Therefore, various human activities and environmental effects research papers, there is a need for scientifically proven information on the effects of increasing exposure to RF-EMFs on nerve cells, including neurodevelopment, function and cognitive functions Calvente et al. However, many studies on the possible influence of electromagnetic waves on neurons have recently been conducted with great interest, but there are conflicting results according to experimental conditions and there is still much to be studied to gain a basic understanding.
Therefore, this paper summarizes the recent studies on the suggested various human activities and environmental effects research papers biological effects of exposure to RF-EMFs Fig. Electromagnetic waves can be classified into Extremely Low Frequency ELF-EMFRF-EMF, and Microwave Radiation depending on the wavelength range. Generally, ELF-EMF, frequencies in the range of 3 to 3, Hz, are generated from the electronics and electric wires used in homes and workplaces.
ELF-EMF is also emitted from the high-voltage power lines that transmit electricity from the power plant to the areas where electricity is used Barr et al. RF-EMF range from kHz to GHz, which generates an electromagnetic field that propagates through space various human activities and environmental effects research papers a radio frequency current is supplied to an antenna ICNIRP, ; Cucurachi et al. RF-EMF is emitted from devices such as mobile phones, Wi-Fi systems, satellite communication systems, radio, TV stations, and interactive radios.
Many of these wireless communication devices are increasingly used in human life Fig. When using electronic devices mobile phones, computers, microwave ovens etc, various human activities and environmental effects research papers.
These waves can be absorbed by human or animal bodies; the specific absorption rate SAR is a numerical expression of these absorbed waves. Electromagnetic waves emitted by mobile phones are of high frequency, thus capable of body temperature increase; such heat reactions are expressed quantitatively by SAR.
Because RF-EMFs can penetrate into the body and cause vibration of charged or polar molecules inside, it is critical to human health and safety. National Radio Research Agency has released SAR standards of SAR-related international organizations and major countries with related matters.
The current emission standard of Republic of Korea for cell phone is 1. However, this safety standard of 1. Previously, epidemiological studies have been done whether children with chronic exposure to ELF-EMF or RF-EMF develop childhood leukemia and in adults, brain tumors and leukemia may occur Lagiou et al.
Although there were some uncertainties, both epidemiological studies found that there is unlikely to be a material increase in risk of adult brain tumors or childhood leukemia resulting from the exposure to either ELF-EMF or RF-EMF. In addition, other studies have not found a direct evidence for the increase in the incidence of childhood leukemia due to ELF-EMF exposure Kleinerman et al.
Moreover, there is no direct correlation between acute lymphoblastic leukemia in children and exposure to ELF-EMF in the home Kleinerman et al. Therefore, various human activities and environmental effects research papers, a standard health risk assessment process, the WHO Task Group of scientific experts concluded that there are no substantive health issues related to ELF-EMFs at levels generally encountered by members of the public, various human activities and environmental effects research papers.
However, it has been hypothesized that a variety of neurological influences may arise as a result of EMF exposure due to the location of the cellular phone and the proximity of the cranial nervous system.
Therefore, a lot of concern is focused on possible carcinogenesis of the cranial nervous system by exposure to RF-EMF Hardell et al. An epidemiological study claimed that using cell phones for one hour a day for more than 10 years could increase the risk various human activities and environmental effects research papers tumors Hardell et al. In addition, cell phone users have an increased risk of malignant gliomas, particularly those with acoustic neuromas.
Moreover, many studies have reported associations between RF-EMF and brain tumors Myung et al. In contrast, there are some studies claiming no association between brain cancer and cell phone usage Benson et al. From this point of view, the observed results to date suggest that the association between the possible carcinogenicity of EMF and the cranial nervous system is complicated by a wide range of confounding variables.
There is no clear evidence to support the causal relationship between increased carcinogenicity following exposure to EMFs Moulder et al. However, the classification of RF-EMFs as possible carcinogens has yet to come to a clear conclusion among scientists. This is due to the fact that only 30 years have passed since the mobile phone has been used in earnest, it needs decades of exposure, and further epidemiological analysis to come to any conclusions.
There is considerable evidence that exposure to RF-EMF could cause various types of genotoxic effects in cells Lai and Singh, ; Lee et al. This have been reported in lymphocytes exposed to various ranges of RF-EMFs Phillips et al.
In addition, RF-EMF exposure has been reported to cause chromosomal instability, alteration of gene expression and gene mutations. Such various human activities and environmental effects research papers toxic effects have been reported in, but are not limited to, neurons, blood lymphocytes, sperm, red blood cells, epithelial cells, hematopoietic tissue, lung cells and bone marrow Magras and Xenos, ; Mashevich et al. It has also been found that exposure to electromagnetic radiation, a type of RF-EMF, various human activities and environmental effects research papers, increases the incidence of chromosomal aneuploidy Mashevich et al.
Genetic toxic effects, including aneuploidy, can lead to genetic disorders with abnormal gene formation, and can even lead to cancer Hoeijmakers, When rats were exposed to MHz RF-EMFs, it was found that albumin leaks via the blood-brain barrier BBB Salford et al. However, the leakages via the BBB were not observed in studies by using rat or in vitro studies Franke et al.
Interestingly, neuronal damage in the cortex, various human activities and environmental effects research papers, hippocampus, and basal ganglia was significantly increased in a rodent model exposed to RF-EMFs Salford et al. In previous studies related to stress and anxiety, exposure to RF-EMF has been reported to induce stress Ray and Behari, ; Millan, ; Bouji et al. It was also examined the effects of microwave EMFs on benzodiazepine receptors related to stress and anxiety in the brain of rats Lai et al.
The change in BBB permeability in rats was reported to be due to signal-induced hyperthermia at 2. It has been shown that not only the continuous but also the pulsed wave 1. However, Fritze et al. To assess the effect of exposure to RF-EMFs on BBB permeability changes, mice were exposed to 2.
Finally, Evans blue, which binds to serum albumin in the rat vein, was injected before and after exposure to investigate whether scopolamine methylbromide crosses the BBB. After exposure to the electromagnetic waves 2. However, no difference in maze performance was observed between the groups administered with the drug before and after exposure to the RF-EMF. It was concluded that the BBB permeability did not change under these experimental conditions. Evans blue from the blood vessels of the rats did not show staining of the parenchyma, which supported this conclusion Cosquer et al.
Other possible changes in the permeability of the BBB by RF-EMFs may be due to changes of blood pressure which has been shown to affect the permeability of the BBB Al-Sarraf and Philip, ; Hossmann and Hermann, Therefore, comprehensive studies on the exposure of RF-EMFs and changes in blood pressure are required. It has been hypothesized that various neurological effects may arise as a result of RF-EMF exposure due to the proximity of the cranial nervous system during cellular phone use.
These neurological effects include headache Frey,changes in sleep habits Wagner et al. Neurological cognitive disorders, such as headache, tremor, dizziness, loss of memory, loss of concentration and sleep disturbance due to RF-EMF have also been reported by several epidemiological studies Kolodynski and Kolodynska, ; Santini et al.
The exposure levels of RF-EMF, commonly encountered in public environments have been found to be nondetrimental level to human Repacholi et al. The radial maze and Morris water maze test showed that learning and memory functions were reduced in rats exposed to 2, MHz EMF Lai et al. Recognition memory was studied using the object recognition test Mortazavi et al. In this study, various human activities and environmental effects research papers, there was no effect on learning and memory at low SAR levels, but at high SAR levels, only some of the exploration activities were changed Dubreuil et al.
Although exposure to RF-EMFs could affect cognitive function such as spatial learning and memory loss in both humans Hossmann and Hermann, ; Preece et al. The hippocampus is involved in spatial memory and learning processes Morris et al. Similarly, exposure to 1, MHz 15 min per day for 8 days, SAR 2. This experiment was performed with a Wi-Fi type, 2.
Despite numerous studies, it remains unclear if RF-EMF exposure is a risk for cognitive function, including memory. Electromagnetic waves, particularly RF-EMFs emitted by mobile phones are absorbed into the brain to such an extent that it can affect the activity of neurons Kleinlogel et al.
Research by the National Institutes of Health has reported that RF-EMFs emitted from mobile phones activates metabolic processes in the human brain Volkow et al. RF-EMFs from cellular phones Glucose metabolism in the brains that were exposed to RF-EMF increased rapidly.
This provided evidence that the brain is sensitive to the effects of RF-EMF exposure Volkow et al. The thermal effects of RF-EMFs suggest the possibility of affecting neuronal activity by temperature generated by mobile phones Wainwright,
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The environmental effects of paper are significant, which has led to changes in industry and behaviour at both business and personal levels. With the use of modern technology such as the printing press and the highly mechanized harvesting of wood, disposable paper became a relatively cheap commodity, which led to a high level of consumption and waste 4. The human activity, among the following, which causes maximum environmental pollution having regional and global impacts, is: (a) Urbanization (b) Industrialisation (c) Agriculture (d) Mining. 5. Production, transformation and use of energy are the major problems of: (a) Industrial activity (b) Sustainable development (c) Global warming (d Environmental Research Letters covers all of environmental science, providing a coherent and integrated approach including research articles, perspectives and review articles. Transparent peer review articles. Submit an article opens in new tab Track my article opens in new tab. RSS. Sign up for new issue notifications
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