Strengthen the prevention and control of heavy met

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Strengthen the prevention and control of heavy metal pollution in soil and eliminate the chemical time bomb around us

China's first soil pollution prevention and control law has been implemented on New Year's Day 2019. On January 21, liuyoubin, spokesman of the Ministry of ecological environment, said that this year, the Ministry of environment will further do a thorough job in the prevention and control of soil pollution, pay close attention to the completion of a detailed survey of the pollution of soil that is not only resistant to high temperature, but also implement the classified management of agricultural land, and strive to promote the safe use and targeted treatment of polluted agricultural land

the Ministry of environment will also focus on areas with heavy metal pollution that are strongly reflected by the public, severely crack down on industries involving illegal heavy metal emissions, cut off the chain of heavy metal pollutants entering farmland, and reduce the risk of excessive heavy metals in grain. In addition, it will strictly control the use of heavily polluted farmland and prohibit the planting of edible agricultural products

in order to strengthen the prevention and control of heavy metal pollution in soil, on May 28, 2016, the State Council issued the action plan for the prevention and control of soil pollution (hereinafter referred to as the "ten soil articles"), which is the action program for the prevention and control of soil pollution in the country at present and in the future

at present, the soil in China is seriously polluted by heavy metals, and more than 10% of the cultivated land is polluted by heavy metals, resulting in a reduction of about 10 million tons of grain production every year, and 12 million tons of inedible grain caused by heavy metal pollution, resulting in an economic loss of at least 20 billion yuan. Since 2008, there have been more than 100 major pollution accidents nationwide, including more than 30 heavy metal pollution accidents, which have caused great harm to people's lives and health

according to the survey, at present, the cultivated land polluted by heavy metals in China has exceeded 180million mu, which is mainly distributed in Hunan, Gansu, Hubei, Sichuan and other provinces (regions) in the south of China. The pollution scope is large, which also increases many difficulties for remediation

soil pollution is different from other environmental pollution, which has a certain degree of concealment, while air pollution, water pollution, etc. are very obvious, once there is pollution, it will show immediately. The presentation speed of soil pollution is slow, and it is difficult to observe the situation and degree of soil pollution with the naked eye. People must know the situation of soil pollution through laboratory monitoring

what is heavy metal pollution? It refers to the epidemic containing cadmium, nickel, mercury and so on, which is called "non-toxic" in the environmental protection industry. They are colorless and odorless "invisible pollution". Although they are extremely difficult to be found in daily life, they do great harm to the environment and human health

heavy metals are mainly through the following five projects with a total budget of £ 275000; Half of the funds come from natep, which pollutes the soil through three ways:

1 Mining: some mines have not yet established stone yards and tailings ponds during mining, and waste rocks and tailings are discharged at will, resulting in the tailings rich in insoluble heavy metals entering the soil. In addition, the remaining metal residues after ore processing enter the groundwater system with rainwater, causing serious soil heavy metal pollution

2. Heavy metal deposition in the atmosphere: heavy metals in the atmosphere

heavy metals in the atmosphere mainly come from industrial production, automobile exhaust emissions and a large number of harmful gases and dust containing heavy metals produced by automobile tire wear. They are mainly distributed on both sides of highways and railways. Most heavy metals in the atmosphere enter the soil through natural sedimentation and rain sedimentation. Heavy metal pollution in the soil on both sides of roads and railways is mainly lead, zinc, cadmium, chromium, cobalt and copper pollution

3. Sewage irrigation

sewage irrigation generally refers to the use of certain treated urban sewage to irrigate farmland, forests and grasslands. Urban sewage includes domestic sewage, commercial sewage and industrial wastewater. Due to economic development, a large number of industrial wastewater flows into the river, so that many heavy metal ions contained in urban sewage enter the soil with sewage irrigation

4. The application of agricultural inputs such as pesticides, chemical fertilizers and plastic films

the application of pesticides containing lead, mercury, cadmium, arsenic and the unreasonable use of chemical fertilizers may lead to the pollution of heavy metals in soil. For example, arsenic is widely used as pesticides, fungicides, rodenticides and herbicides. A small amount of nitrogen fertilizer has a high content of lead. Heat stabilizers used in the production of agricultural plastic films contain cadmium and lead, which may cause heavy metal pollution in the soil in the process of extensive use of plastic greenhouses and mulching films

5. Agricultural use of sludge and some solid wastes

some solid wastes are applied to the soil directly or through processing as fertilizers, resulting in heavy metal pollution in the soil. For example, the waste produced by domestic animal manure and animal processing often increases the content of some heavy metal elements in the soil after being applied as fertilizers due to the addition of certain heavy metal salts in its feed; With the development of China's industry and the acceleration of urban construction, more and more sludge is produced by sewage treatment plants. In addition to higher organic matter, nitrogen, phosphorus and other nutrients, these sludge often also contains heavy metals such as chromium, lead, copper, arsenic and so on, and it is very easy to exceed the control standard. Once applied to farmland, the content of heavy metals in soil can be increased to varying degrees

in the process of soil being polluted by heavy metals, these polluting elements generally show a vertical decreasing distribution, which is difficult to fundamentally control. With the passage of time, the depth of heavy metal pollution in soil will gradually deepen, and the impact will be worse

heavy metal pollution, for humans at the top of the food chain, the damage to body organs is often lifelong and irreversible. Moreover, heavy metals have a enrichment effect on animals and human body. Once they enter the body, they are difficult to be naturally discharged or completely removed

researchers found that at least 23 kinds of heavy metals are everywhere in our lives

once these weight reducing packaging metals are ingested into the body, they will stick to the body, especially hidden in fat cells, similar to fat soluble toxins, and it is difficult to get rid of them. Worse, fat cells that adsorb heavy metals will also adsorb more substances (including metals), making these heavy metals stay in the body for a long time. Sometimes weight loss or intermittent fasting can rule out a small number of heavy metals. One of the reasons is that fat cells shrink and release some long-term dormant heavy metals in the body

soil heavy metal pollution is like a chemical time bomb lurking around us. The best way to eliminate the danger is to cut off the inflow of heavy metals as soon as possible

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