The difference between electromagnetic radiation and electromagnetic pollution

Nowadays, "anti-radiation" has become a buzzword and a "selling point" for the added value of goods. Myopia lenses that protect against computer radiation cost at least dozens of yuan more than ordinary lenses. Clothes are also made of anti-radiation fabrics. Even cacti have become a must-have on the desk of office white-collar workers because of their anti-radiation effects.

Radiation is invisible and intangible. Are there any scientific evidences for rumors that it harms the skin, affects fertility, and causes cancer? What exactly is radiation? Is electromagnetic radiation really the devil of pollution?

What is Radiation

Zhao Ling, who works at a state-owned enterprise in the north of Changsha, is pregnant. Although she wears anti-radiation maternity clothes to work every day, she is still worried: "There are microwave ovens at home, computers in the office, and mobile phones also have radiation. I feel scared when I see TV towers and communication antennas on the street."

"Simply put, electromagnetic radiation is a physical phenomenon in which energy propagates through space in the form of electromagnetic waves. Any vibrating electric charge generates an electromagnetic field around it." Li Donggen, a member of the C branch of the National Electromagnetic Compatibility Standardization Technical Committee, explained that "the radio waves we refer to in our daily lives are actually radio frequency electromagnetic radiation."

From a professional perspective, the interaction between electric and magnetic fields generates electromagnetic waves. The phenomenon of electromagnetic waves being emitted or gathered into the air is called electromagnetic radiation. Electromagnetic radiation is a substance that exists in a special form that is invisible and intangible. The earth where humans live is itself a large magnetic field. The thermal radiation and lightning on its surface can generate electromagnetic radiation. The sun and other planets also continuously generate electromagnetic radiation from outer space. The natural magnetic field, sunlight, household appliances, etc. around humans will emit radiation of varying intensities.

Understanding the sources of electromagnetic radiation in life

Li Donggen, a member of the National Electromagnetic Compatibility Standardization Technical Committee, said that in the magnetic field of household electrical appliances, we are in the frequency band of low frequency 50 Hz to microwave. In other words, everything from computers, televisions, refrigerators, air conditioners, microwave ovens to mobile phones, electric blankets, hair dryers, electric irons, electric shavers, etc., all have radiation.

Secondly, industrial and medical equipment generate various complex electromagnetic radiation and electromagnetic fields during operation. High-voltage transmission lines and electrified railways that we usually see also generate electromagnetic radiation during operation. In addition, radio, television, mobile phones, and base stations can all generate electromagnetic fields.

In addition, electromagnetic radiation is also generated by industry, scientific research, medical equipment, high-voltage transmission lines, substations, radio and television signal transmission towers, communication base stations, subways, trams, electrified railways, and the transmission of radio and television programs.

The former Soviet Union and the United States National Bureau of Standards formulated electromagnetic radiation health standards in 1965 and 1966 respectively. my country has also always attached great importance to the protection of electromagnetic radiation. Since 1988, health standards such as the "Electromagnetic Radiation Protection Regulations" and the "Environmental Electromagnetic Wave Health Standards" have been promulgated one after another. In 1997, the State Environmental Protection Administration issued the "Electromagnetic Radiation Environmental Protection Management Measures", which made management legal. In 2000, the Ministry of Health, the Environmental Protection Administration and others began to draft mandatory national standards, "Mobile Phone Electromagnetic Radiation" and "Electromagnetic Radiation Exposure Limits and Measurement Methods".

Electromagnetic radiation does not equal electromagnetic pollution

Yao Yunxian, a professor at Changsha Environmental Protection Vocational and Technical College, said that construction projects that can generate electromagnetic radiation must undergo professional environmental assessments before construction, and must also be monitored during and after construction to see if they can meet environmental protection requirements.

Experts say that when electromagnetic radiation energy (the size of which is expressed by field intensity) is controlled within a certain limit, it is not only harmless to the human body, organisms and other organisms, but also beneficial. Whether it is harmful to the human body depends mainly on the frequency and power of electromagnetic radiation. Only when these two factors exceed a certain allowable value and cause radiation pollution, will it have a negative impact on the human body.

In May 2006, the World Health Organization released Fact Sheet No. 304, "Electromagnetic Fields and Public Health Base Stations and Wireless Technologies", stating that, given the very low exposure levels and the research results collected so far, there is no convincing scientific evidence to prove that weak radio frequency signals from (mobile communication) base stations and wireless networks will cause harmful effects on biological health. It can be seen that electromagnetic radiation is not directly equivalent to electromagnetic pollution, nor is it directly linked to human health.

He Zuoxiu, a famous physicist and academician of the Chinese Academy of Sciences, has also clearly stated that, up to now, there has not been a confirmed case of electromagnetic radiation causing harm to the human body in the world. It can be seen that it is completely unnecessary to worry too much about the impact of (mobile communication) base station radiation on human health.