The substances that affect our living environment are called environmental pollutants, which come from both natural and man-made aspects. The causes of environmental pollution can be roughly divided into three types: chemical, physical and biological. Here is a brief introduction to environmental pollutants:
Powder dust
Dust is one of the most extensive and harmful pollutants in the atmospheric environment. Dust in the atmospheric environment can be divided into two types: floating dust and dustfall. The so-called floating dust refers to the floating particles with dust particles below 10 micron, and the so-called dust suppression refers to the substances that the pollutants in the atmosphere settle by their own weight.
Whether it is floating dust or falling dust, it has an impact on the atmospheric environment, temperature, climate, sunshine, visibility, human health and animals and plants. Dust, especially 0.5-5 micron floating dust, is the most harmful to people, because it contains a variety of toxic metals or carcinogens, which can easily enter the human body with breathing, and about half of them can attach to the lung wall, which constitutes or aggravates human respiratory diseases. According to the survey, when the concentration of floating dust is 100 μ g/m3, the respiratory tract infection of children increases obviously; When the concentration of floating dust is 200 μ g/m3, the mortality of chronic respiratory diseases increases; When the concentration of floating dust is 300 μ g/m3, respiratory diseases are aggravated. When the concentration of floating dust is 800 μ g/m3, the mortality of respiratory diseases and heart diseases increases and traffic accidents are serious. Therefore, the state stipulates that the maximum allowable primary concentration of air dust in residential areas is 0.50 mg/m3 and the daily average concentration is 0. 15 mg/m3.
fluoride
Fluoride is usually measured as fluorine or hydrogen fluoride. Except for local fluorine-polluted areas, fluoride is contained in the air and drainage of iron and steel plants, phosphate fertilizer plants, electrolytic aluminum plants, glass-ceramics plants and fluoroplastics production plants.
Fluoride is harmful to animals, plants and human body. The effect on plants is 10- 100 times greater than that of sulfur dioxide, and fluorine can accumulate in plants. When the concentration of fluorine reaches 50- 100ppm, the tissue of plant leaves will be necrotic. Drinking water and feed with high fluorine content will cause diseases such as teeth and bones. Fluoride is 20 times more harmful to human body than sulfur dioxide, mainly bone injury, manifested as long bone pain and osteoporosis in limbs, and in severe cases, bone hyperplasia or deformation is prone to spontaneous fractures; Secondly, it damages the skin, making it itchy, painful, eczema and various dermatitis.
Therefore, the maximum allowable concentration of fluoride (instead of hydrogen fluoride) in the air of residential areas is 0.02 mg/m3, and the daily average concentration is 0.007 mg/m3. The maximum allowable concentration of hydrogen fluoride in the air of workplace is1mg/m3; The maximum allowable fluorine concentration in surface water is1mg/l; The fluorine concentration in drinking water should not exceed 1.0 mg/L, and the suitable concentration is 0.5- 1.0 mg/L. ..
Treat with chloride
Chlorine in gas is mainly chlorine and hydrogen chloride; The chloride in water is mainly hydrochloride.
Chlorine is a yellow-green toxic gas with a strong smell. It is a strong oxidant, which reacts with carbon dioxide to produce phosgene (COCL2) with greater toxicity. The specific gravity of chlorine gas is 2.49, so when chlorine gas is discharged or leaked, it mainly sinks to the bottom of the air along the ground. Chlorine mainly comes from chlorination roasting or chlorination volatilization in chemical industry, light industry and nonferrous metal smelting.
Chlorine gas is harmful to people through eyes, nose, throat, upper respiratory tract and deep respiratory tract. When slightly poisoned, I feel chest tightness, itchy throat, dry cough and stinging eyes; In deep poisoning, the body temperature rises, complicated with toxic pulmonary edema and even shock. Therefore, the maximum allowable concentration of chlorine in residential air is 0. 1mm/m3, and the daily average is 0.03mg/m3.
Hydrogen chloride is a colorless gas with an odor of * *, which is harmful to human health mainly through respiratory tract. Long-term exposure to hydrogen chloride can cause laryngeal mucosa, nasal mucosa ulcer, tooth corrosion and gastrointestinal diseases. Hydrogen chloride gas also has a serious corrosive effect on metals. Therefore, the maximum allowable concentration of hydrogen chloride gas in the atmosphere of residential areas is 0.05 mg/m3, and the daily average concentration is 0. 1.5 mg/m3.
......& gt& gt
Question 2: Causes of environmental pollution Environmental pollution refers to the phenomenon that human beings directly or indirectly discharge substances or energy that exceed their self-purification ability to the environment, thus reducing the environmental quality and adversely affecting human survival and development, ecosystems and property. Specifically, it includes: water pollution, air pollution, noise pollution and radioactive pollution. Water pollution refers to the interference of some substances in water bodies. It will lead to the change of its chemical, physical, biological or radioactive pollution characteristics, thus affecting the effective use of water, endangering human health or destroying the ecological environment, and causing the deterioration of water quality. Air pollution means that the concentration of pollutants in the air reaches a harmful level, thus destroying the ecological system and the conditions for the normal survival and development of human beings. A phenomenon that harms human beings and creatures. Noise pollution refers to the phenomenon that the environmental noise generated exceeds the national environmental noise emission standard and interferes with the normal work, study and life of others. Radioactive pollution refers to radioactive substances or rays that exceed the national standards on the surface or inside of substances, human bodies, places and environmental media due to human activities. For example, exceeding national and local pollutant discharge standards, discharging pollutants in excess of categories, quantities and concentrations; Loading and transporting oil or toxic goods without taking measures to prevent spillage, causing the goods to fall into the water and causing water pollution; Illegal discharge of toxic and harmful substances into the atmosphere, causing air pollution accidents, and so on. _ _ _ _ _ Suggestions for improvement: 1. Fully understand the significance of environmental protection; 1. Positive progress has been made in environmental protection. The CPC Central Committee and the State Council attached great importance to environmental protection, and adopted a series of major policies and measures, and all regions and departments continued to strengthen environmental protection. With the rapid growth of the national economy and the remarkable improvement of people's consumption level, the environmental quality of the whole country is basically stable, the environmental quality of some cities and regions has improved, the total discharge of most major pollutants has been controlled, the emission intensity of industrial products has decreased, the environmental governance of key river basins and regions has been continuously promoted, ecological protection and governance have been strengthened, the nuclear and radiation supervision system has been further improved, and the environmental awareness and public participation of the whole society have been significantly improved. China has earnestly fulfilled international environmental conventions and established a good international image. (2) The environmental situation is still very grim. Although China has made positive progress in environmental protection, the grim environmental situation has not changed. The discharge of major pollutants exceeds the environmental carrying capacity, and the river sections flowing through the city are generally polluted. In many cities, air pollution is serious, acid rain pollution is aggravated, the harm of persistent organic pollutants is beginning to appear, and the soil pollution area is expanding. The pollution in coastal waters has intensified, and there are hidden dangers in the safety of nuclear and radiation environment. Ecological damage is serious, soil erosion is extensive, rocky desertification and grassland degradation are aggravated, biodiversity is reduced, and ecosystem function is deteriorated. Environmental problems that have appeared in stages in the process of industrialization in developed countries for hundreds of years have concentrated in China in recent 20 years, showing structural, compound and compressive characteristics. Environmental pollution and ecological destruction have caused huge economic losses and endangered people's health. Affect social stability and environmental security. In the next 15 years, the population of China will continue to increase, the economic aggregate will quadruple again, the consumption of resources and energy will continue to increase, and the pressure on environmental protection will be increasing. (3) environmental protection laws and regulations, systems and work do not meet the requirements of the task. At present, some places attach importance to GDP growth and ignore environmental protection. The legal system of environmental protection is not perfect, and environmental legislation can not fully meet the needs of the situation. The phenomenon of non-compliance with laws and lax enforcement is more prominent. The environmental protection mechanism is imperfect, the investment is insufficient, there are many historical debts, the pollution control process is slow, and the marketization degree is low. The environmental management system has not been completely straightened out, and the efficiency of environmental management needs to be improved. The supervision ability is weak, and the national environmental monitoring, information, science and technology, education and comprehensive evaluation ability are insufficient. The environmental awareness and public participation level of some leading cadres need to be strengthened. (4) Environmental protection should be placed in a more important strategic position. Strengthening environmental protection is an important measure to implement Scientific Outlook on Development, an inherent requirement for building a well-off society in an all-round way, a practical action to persist in governing for the people and improve the ability to govern, and a powerful guarantee for building a harmonious socialist society. Strengthening environmental protection is conducive to promoting economic restructuring and the transformation of growth mode, and achieving faster and better development. It is conducive to promoting the development of environmental protection and related industries, cultivating new economic growth points and increasing employment; It is conducive to improving the environmental awareness and moral quality of the whole society and promoting the construction of socialist spiritual civilization; Conducive to ensuring people's health, improving the quality of life and prolonging life; Conducive to safeguarding the long-term interests of the Chinese nation and leaving a better life for future generations ... >>
Question 3: Some information about the causes of environmental pollution With the rapid development of industry and the concentration of urban population, people are emitting more and more pollutants in their production and life, and the impact of pollutants on the human environment is becoming more and more serious. Environmental problems have become one of the main problems facing the world today. Protecting the environment is a basic national policy of our country.
The substances that affect our living environment are called environmental pollutants, which come from both natural and man-made aspects. The causes of environmental pollution can be roughly divided into three types: chemical, physical and biological. Here is a brief introduction to environmental pollutants:
Powder dust
Dust is one of the most extensive and harmful pollutants in the atmospheric environment. Dust in the atmospheric environment can be divided into two types: floating dust and dustfall. The so-called floating dust refers to the floating particles with dust particles below 10 micron, and the so-called dust suppression refers to the substances that the pollutants in the atmosphere settle by their own weight.
Whether it is floating dust or falling dust, it has an impact on the atmospheric environment, temperature, climate, sunshine, visibility, human health and animals and plants. Dust, especially 0.5-5 micron floating dust, is the most harmful to people, because it contains a variety of toxic metals or carcinogens, which can easily enter the human body with breathing, and about half of them can attach to the lung wall, which constitutes or aggravates human respiratory diseases. According to the survey, when the concentration of floating dust is 100 μ g/m3, the respiratory tract infection of children increases obviously; When the concentration of floating dust is 200 μ g/m3, the mortality of chronic respiratory diseases increases; When the concentration of floating dust is 300 μ g/m3, respiratory diseases are aggravated. When the concentration of floating dust is 800 μ g/m3, the mortality of respiratory diseases and heart diseases increases and traffic accidents are serious. Therefore, the state stipulates that the maximum allowable primary concentration of air dust in residential areas is 0.50 mg/m3 and the daily average concentration is 0. 15 mg/m3.
fluoride
Fluoride is usually measured as fluorine or hydrogen fluoride. Except for local fluorine-polluted areas, fluoride is contained in the air and drainage of iron and steel plants, phosphate fertilizer plants, electrolytic aluminum plants, glass-ceramics plants and fluoroplastics production plants.
Fluoride is harmful to animals, plants and human body. The effect on plants is 10- 100 times greater than that of sulfur dioxide, and fluorine can accumulate in plants. When the concentration of fluorine reaches 50- 100ppm, the tissue of plant leaves will be necrotic. Drinking water and feed with high fluorine content will cause diseases such as teeth and bones. Fluoride is 20 times more harmful to human body than sulfur dioxide, mainly bone injury, manifested as long bone pain and osteoporosis in limbs, and in severe cases, bone hyperplasia or deformation is prone to spontaneous fractures; Secondly, it damages the skin, making it itchy, painful, eczema and various dermatitis.
Therefore, the maximum allowable concentration of fluoride (instead of hydrogen fluoride) in the air of residential areas is 0.02 mg/m3, and the daily average concentration is 0.007 mg/m3. The maximum allowable concentration of hydrogen fluoride in the air of workplace is1mg/m3; The maximum allowable fluorine concentration in surface water is1mg/l; The fluorine concentration in drinking water should not exceed 1.0 mg/L, and the suitable concentration is 0.5- 1.0 mg/L. ..
Treat with chloride
Chlorine in gas is mainly chlorine and hydrogen chloride; The chloride in water is mainly hydrochloride.
Chlorine is a yellow-green toxic gas with a strong smell. It is a strong oxidant, which reacts with carbon dioxide to produce phosgene (COCL2) with greater toxicity. The specific gravity of chlorine gas is 2.49, so when chlorine gas is discharged or leaked, it mainly sinks to the bottom of the air along the ground. Chlorine mainly comes from chlorination roasting or chlorination volatilization in chemical industry, light industry and nonferrous metal smelting.
Chlorine gas is harmful to people through eyes, nose, throat, upper respiratory tract and deep respiratory tract. When slightly poisoned, I feel chest tightness, itchy throat, dry cough and stinging eyes; In deep poisoning, the body temperature rises, complicated with toxic pulmonary edema and even shock. Therefore, the maximum allowable concentration of chlorine in residential air is 0. 1mm/m3, and the daily average is 0.03mg/m3.
Hydrogen chloride is a colorless gas with an odor of * *, which is harmful to human health mainly through respiratory tract. Long-term exposure to hydrogen chloride can cause laryngeal mucosa, nasal mucosa ulcer, tooth corrosion and gastrointestinal diseases. Hydrogen chloride gas also has a serious corrosive effect on metals. Therefore, the maximum allowable concentration of hydrogen chloride gas in the atmosphere of residential areas is 0.05 mg/m3, and the daily average concentration is 0. 1.5 mg/m3.
oxynitride
There is no nitrogen oxide in the gas ... >; & gt
Question 4: What are the main causes of environmental problems? Man's insatiable desire for material comforts is the most fundamental cause of serious environmental pollution today.