Modern scientific research shows that electromagnetic waves have a great impact on the growth and development of animals and plants. For example, a pot of Chlorophytum with lush branches and leaves, bright green color, and normal growth is placed in front of a 25-inch color TV screen. If the TV is played continuously for several nights, the leaves of Chlorophytum will scorch, yellow spots will appear in the veins, and in severe cases, the leaves will become chlorotic and fester. At this time, move the spider plant outdoors and nurse it for a few weeks, and the branches and leaves will return to their original state, full of vitality. It can be seen that the invisible electromagnetic waves and rays released by TV have a great impact on the growth of plants. Recently, "Newspaper Digest" reprinted foreign reports on "Electromagnetic fields are harmful to the human body". Research data shows that as long as the intensity of the electromagnetic field reaches 0.2 microtesla, it will cause harm to the human body that lives in the electromagnetic field for a long time. According to scientific measurements, the intensity of the electromagnetic field existing in the surrounding space 20cm away from the 380V three-wire high-voltage power line is about 20 to 30 μT, while the intensity of the electromagnetic field in the space directly below the 400kV high-voltage power line is about 40 μT. It can be seen that with the increase of household appliances, as long as they use household appliances, people will work, study, and live in a space full of electromagnetic fields, and they will be harmed by electromagnetic fields to varying degrees.
Since electromagnetic fields can cause harm to the human body, will electromagnetic fields also affect the growth and development of plants? The following set of comparison pictures is enough to answer this question.
There are two tall cedars in front of the office where the author works, as shown in the picture. These two cedars are tall and straight, about four stories high, with lush branches and leaves, and a crown like a canopy. Figure 1 is a photo of two cedar trees taken by the author standing on the second floor and looking up. The one on the left is close to the three-wire high-voltage wire, while the one on the right is far away from the high-voltage wire. As you can see from the photo, the branches and leaves of a cedar tree on the right grow normally. Due to the effect of the earth's gravitational field, the branches and leaves grow in balance around the trunk in the left and right, front and rear directions, showing a symmetrical distribution. The branches of the one on the left below the three-wire high-voltage power line are roughly symmetrically distributed in the left and right, front and rear directions, while the branches next to and above the three-wire high-voltage power line are symmetrically distributed in the front and rear, but are severely asymmetrical in the left and right directions. That is, the branch on the side close to the three-wire high-voltage wire points downward and bends to the right to avoid the three-wire high-voltage wire. On the right side away from the three-wire high-voltage power lines, the branches grow normally and distribute radially to the right, as shown in Figure 2. Figure 2 is a close-up shot of a cedar tree on the left taken while standing on the third floor.
Two cedars grow in the same ecological environment, about eight meters apart, and receive roughly the same amount of sunlight each year. Why are there obvious differences in the distribution of branches? The author thinks that it is mainly the result of the long-term influence of the electromagnetic field generated by the three-phase transmission lines. As can be seen from Figure 1, the cedar on the left is close to the three-wire high-voltage power line. This set of high-voltage wires is used to supply power to the school-run factories all year round. The line voltage is 380V and the phase voltage is 220V. In Figure 1, the cedar branches on the left above the three-wire high-voltage wires are all within 1 meter of the three-wire high-voltage wires. There is an electromagnetic field in the space around the three-wire high-voltage wire. According to Bizarre's law, the vector form of the magnetic field generated around the current of the three-wire high-voltage wire can be expressed as Weakness is related to the distance r from a certain point in the electromagnetic field to the three-wire high-voltage electricity. Qualitatively speaking, the smaller the distance r, the greater the field strength, and vice versa.
In view of the above, the branches above the three-wire high-voltage power line of the cedar tree on the left are relatively close to the three-wire high-voltage power line. They are subject to the long-term effect of a strong electromagnetic field, causing the branches to move towards the three-wire high-voltage power line and away from the three-wire high-voltage power line. There is a difference in the side growth speed. The former grows fast and the latter grows slow, so the branches bend downward and to the right under the action of the earth's gravitational field. The cedar tree on the right is seven or eight meters away from the three-wire high-voltage power line. Although it is also affected by the electromagnetic field, the intensity of the electromagnetic field is weak, so its growth is relatively less affected.
Later, the layout of the three-wire high-voltage wires in the school factory where the author works was changed. The original three-wire high-voltage wires were removed, but the poles still existed. In this way, the cedar on the left was no longer affected by the strong electromagnetic field. After half a year, the branches that originally bent to the right and downward gradually bent to the left and upward. The distribution gradually becomes symmetrical in the left and right, front and rear directions. This fact also adds to the
Why are the branches above the three-wire high-voltage power lines asymmetrical from left to right, while the branches below are basically symmetrical?
To sum up, electromagnetic fields not only affect human health but also affect the growth of plants. The degree of influence on the growth and development of plants is directly related to the intensity and direction of the electromagnetic field in the space around the plants.
As early as 1975, experts predicted that with the development of urban economy and population growth, electronics, communications, computers, automobiles and electrical equipment have entered households in large numbers, and the man-made electromagnetic energy in urban space will increase by 7% every year. ~14% increase.
In other words, the urban electromagnetic energy density can increase by up to 26 times in 25 years, and by up to 700 times in 50 years!
In the past 30 years, 25,000 articles have been published on the biological effects and medical applications of electromagnetic fields. Although people think that research in this field is still very imperfect, in fact, the accumulation of knowledge in this field has far exceeded many traditional fields, such as some branches of chemistry.
What occupational diseases can radiation cause?
A series of studies have shown that it is an indisputable fact that employees who work closely with electromagnetic waves will be harmed by radiation.
The Hunan Provincial Institute of Labor Health and Occupational Disease Prevention and Control recently completed a study to explore the current situation of microwave radiation pollution. They conducted group health checks on relevant technical personnel engaged in microwave operations and office staff not exposed to microwaves, and also monitored the operating environment.
The research results showed that the detection rates of insomnia, palpitations, and hair loss in the microwave exposure group were 12.16, 9.46, and 18.92 respectively, which were significantly higher than those in the control group. Microwave workers also had a higher incidence of vision loss (35.13) - this may be related to the heating effect of microwaves. Their electrocardiogram abnormality detection rate also reached 37.84, while the control group was only 16.13. There was a significant difference between the two groups. ——This change may be related to microwave radiation affecting the function of the cardiac autonomic nervous system and causing cardiac conduction dysfunction.
Guo Jiuji from Shanghai Second Medical University and other experts have made dynamic observations on the health status of workers working with microelectromagnetic waves for two and a half years. The results show that when the microwave field strength is 50 to 100μW/cm2 (microwatt per square centimeter (this number is higher than the national standard 40μW/cm2). Workers in neurasthenia syndrome, electroencephalogram, electrocardiogram, cardiac function, cerebral blood flow diagram, cerebrovascular tension, white blood cells and other health factors have Significant changes (see chart).
In addition, because the human eye tissue is rich in water, it is easy to absorb electromagnetic radiation, and the blood flow is small, and the temperature easily rises under electromagnetic radiation. Therefore, when strong electromagnetic waves irradiate the eyes for a long time, the human eye will be affected by the temperature. Elevated levels cause lens proteins to coagulate, which can form "microwave cataracts."
Public *** area: Not exceeding the standard does not mean harmless
In the public *** environment, the impact of electromagnetic fields on people's physical and mental health is a matter of greater concern to people . Today, the transmitting stations of radio and television systems and mobile phone systems have been distributed in various cities. The distance between mobile phone base stations and base stations in megacities such as Beijing, Shanghai, and Guangzhou is even within 300 meters. Living among towers of towers, how much impact does microwave have on us?
Since the impact of electromagnetic waves on people in the general environment is a long-term effect, research on it is also a long process.
It is an indisputable fact that electromagnetic waves can stimulate the human body to produce certain biological effects. What scientists now want to prove is whether this effect is dangerous. It has been proven that even short-term exposure to high-intensity electromagnetic fields will have harmful effects on the body. As for whether exposure to low-intensity electromagnetic fields will have harmful effects on the body, there is no conclusion in the scientific community so far.
According to environmental monitoring data statistics, the total number of base stations with electromagnetic radiation intensity at sensitive environmental points around China Mobile phone base stations exceeds 8 μW/cm2 (this is the environmental management target value, and long-term higher than this value may be harmful to the body) Close to 1, some even exceed the national standard of 40μW/cm2.
For example, the total number of China Mobile and China Unicom base stations in Beijing is about 3,000, and the total number of monitoring exceedances has reached 6; the total number of China Mobile and China Unicom base stations in Liaoning Province is about 5,000, and about 10 exceed the standards.
“As for the electromagnetic radiation environmental standards set by the country, China’s requirements are stricter than those of developed countries such as the United States. However, in fact, the intensity of electromagnetic waves in Chinese cities is generally much higher than that of cities in other countries—— In other words, the intensity of electromagnetic radiation in the public environment of other countries is generally far lower than their standards," Cao Zhaojin, an electromagnetic radiation research expert at the Environmental Health Monitoring Institute of the Chinese Academy of Preventive Medicine, said in an interview with this reporter. "Based on the current research results, it is difficult to draw a conclusion on how much radiation will cause harm to the body. When the radiation intensity is close to the standard, not exceeding the standard does not mean it is harmless. This is also the requirement of developed countries to disclose the environmental electromagnetic radiation intensity. The reason is far below the standard. ”
In other words, in China’s big cities, there are quite a few public environments whose electromagnetic radiation intensity is at least on the edge of danger.
Are mobile phones really dangerous? !
Mobile phones transmit information by emitting electromagnetic waves. Although its transmission power has been reduced from the original 3-5W to the current 0.25-2W, the mobile phone antenna is too close to the brain during a call (5-10 cm), talking for a long time means being exposed to electromagnetic wave radiation for a long time.
According to Cao Zhaojin, experts at home and abroad have measured the electromagnetic wave intensity near the antenna during mobile phone calls. The monitoring results are: the power density value around the antenna of most mobile phones is tens to hundreds of μW/cm2. The maximum time value can reach about 1000μW/cm2.
It can be seen that when using a mobile phone, the local environment contains strong electromagnetic waves that far exceed environmental standards.
Experts used mobile phones with a frequency of 900 MHz to test volunteers. The results showed that the skin temperature of the nostrils and occiput on the side of the subject using the mobile phone increased significantly, with a maximum increase of 2.5°C, while the temperature of the skin on the other side increased significantly. There is no increase in skin temperature on the side - this thermal effect is already quite strong. If there is an obvious thermal effect deep under the skin to the brain, it will have a significant impact on the cranial nerves.
Cao Zhaojin and others studied the impact of mobile phone electromagnetic radiation on users' neurobehavior. The results showed that the average reaction time of the mobile phone user group was significantly prolonged, that is, the reaction slowed down. This suggests that cell phone use can cause adverse neurobehavioral consequences.
Cao Zhaojin’s research team further studied the impact of mobile phones on users’ sleep quality and depression. The results showed that mobile phones significantly increased the insomnia rate of users, and to a certain extent, increased the incidence of depression and depression in users. Depression severity. Their related research also shows that the number of years of mobile phone use is positively correlated with chest tightness, nausea and loss of appetite. Long-term use of mobile phones may also cause neurasthenia.
Radiation Research Timeline
It has been suggested that electromagnetic field exposure will cause cancer, behavioral changes, memory loss, Parkinson's and Alzheimer's diseases, and many other diseases - although not yet Not enough evidence was found to prove this.
“We live in a society that is highly dependent on science and technology, but in this society, few people really understand science and technology.”
This sentence by Carl Sagan The famous quote well summarizes the situation of modern people facing the ubiquitous electromagnetic radiation. When a danger is new, its potential impact cannot be measured, and people's faith in science gradually declines, people enter the realm of the "precautionary principle" - the "precautionary principle" is a new concept proposed by the scientific community. Used to prevent or limit possible harm caused by objects or actions, this principle emphasizes that it must be established before harm to health is caused.
The latest definition of health by experts from the World Health Organization (WHO) is: Health should be a state of complete physical, mental and social behavior, not just the absence of diseases and defects. In this sense, even if electromagnetic radiation in the public environment only affects people's psychology, scientists must still face and solve it as a problem.
WHO and IARC (International Research Institute on Cancer) have developed a timetable for assessing the health effects of electromagnetic fields. In 2004, IARC will have sufficient research results to handle an assessment of the carcinogenic effects of electromagnetic radiation. WHO will complete a comprehensive assessment of the harm to health caused by electromagnetic radiation in 2005-2006.
As long as there is electricity, electromagnetic waves will be generated. If the frequency of electromagnetic waves exceeds 105 Hz, it can penetrate the human body and cause functional disorders - in mild cases, symptoms such as dizziness and fatigue, insomnia, loss of appetite, irritability, blood pressure changes, leukopenia, etc.; in severe cases, it can cause vision loss, cataracts, Gene defects can even cause cancer. According to foreign surveys, children exposed to strong electromagnetic waves for a long time have a cancer incidence rate that is 2 to 5 times higher than that of children exposed to weak electromagnetic waves; the risk of breast cancer in women increases by more than 7 times in households with high-voltage wires around them; electric blankets are commonly used For pregnant women, the development of the fetus will be affected or even miscarriage; for pregnant women who often talk on mobile phones, the fetus may be malformed; for people who are often affected by electromagnetic waves, the bioelectricity in the body will be disturbed, and the incidence of brain cancer is more than 6 times higher than that of the average person.
What preventive measures should people take in an environment polluted by electromagnetic waves?
1. Keep your distance. The distance from the TV should be the screen size times 6, the distance from the microwave oven should be 2.5 to 3 meters, and the distance from high-voltage power lines to 0.5 million volts/meter is generally considered a safe zone.
2. Reduce contact. People who frequently use computers should take a quarter-hour break for every hour they work, and should work no more than 32 hours per week.
3. Improve the environment. Pay attention to air circulation, the temperature and humidity should be moderate, and it is best not to place household appliances in the bedroom.
4. Personal protection. Pregnant women, children, the frail and sick, those who are allergic to electromagnetic radiation, and those who have been in an environment with excessive electromagnetic wave pollution for a long time should choose and use protective equipment that suits them.
5. Use your mobile phone less. Minimize the use of cell phones, walkie-talkies and cordless phones, and keep your conversations short when necessary; do not always hang your cell phone on your body.
6. Use less electric blankets. The electromagnetic wave pollution of electric blankets is serious, and long-term use of electricity is harmful to the human body. When the weather is cold and must be used, it is recommended to turn on the electricity to warm the bed and immediately cut off the power to reduce electromagnetic wave pollution.
7. Use shielding materials to reduce electromagnetic wave pollution. For facilities that produce electromagnetic pollution, shielding materials that shield, reflect or absorb electromagnetic waves can be used, such as copper, aluminum, steel plates, polymer films, etc. (