Is the health statement on the food label accurate and reliable?

Moscow Institute of Nutrition announced the conclusion of a survey to the society that "eating only green food is good for health" is a wrong view, and if you only eat green food, your health will be damaged. This conclusion undoubtedly poured cold water on the public's enthusiasm for green food. So, what about green food? What is a real "pollution-free vegetable"? The reporter interviewed relevant experts and scholars. What is green food? Green food must meet the following conditions: 1. Products or raw materials must meet the eco-environmental quality standards of green food; 2. Crop planting, livestock and poultry breeding, aquaculture and food processing must conform to the operating rules for green food production; 3. Products must meet the quality and hygiene standards of green food; 4. The outer packaging of products must conform to the national general food labeling standards and the specific packaging, decoration and labeling regulations of green food. According to experts, green food standards are divided into two technical levels, namely AA-level green food standards and A-level green food standards. AA-level green food standard requires that the environmental quality of the origin conforms to the environmental quality standard of the origin of green food. In the production process, chemical synthetic pesticides, fertilizers, food additives, feed additives, veterinary drugs and production raw materials harmful to the environment and human health are not used, but technologies such as using organic fertilizers, planting green manure, crop rotation, biological or physical methods are adopted to fertilize the soil, prevent diseases, weeds and insects, and protect or improve the product quality, thus ensuring that the product quality meets the requirements of green food product standards. A-grade green food standard requires that the environmental quality of the producing area conforms to the environmental quality standard of the producing area of green food. In the production process, in strict accordance with the requirements of "Guidelines for the Use of Green Food Production Materials" and production operation procedures, limited chemical synthesis production materials are used, and biological methods are actively adopted to ensure that the product quality meets the requirements of green food product standards. In order to distinguish it from ordinary food, green food has a unified logo. Green food signs have specific graphics. The green food pattern consists of three parts: the sun above, the leaves below and the buds. The sign map is a right circle, representing protection and safety. Eating vegetables is also classified in China. There are five categories of concepts and standards related to the quality and safety of vegetable products, and the order of safety and reliability is safe vegetables, pollution-free vegetables, general products, green foods and organic foods. Safe food: Safe food that will not cause acute poisoning after eating. The corresponding detection standard is rapid detection method, which has certain limitations and can only determine organophosphorus and other pesticides, and is not suitable for sulfur-containing vegetables. Pollution-free vegetables: refers to the products whose production environment, production technology and product quality meet the pollution-free standards of the state or agricultural industry, and have been inspected by the origin or quality supervision and inspection institutions, certified by relevant departments and marked as pollution-free food. At present, the Ministry of Agriculture has issued 199 standards for pollution-free food and 13 standards for vegetable products, including pesticide residues and heavy metals. General products: this word is rarely heard, which refers to products that do not specifically refer to pollution-free food, green food and organic food. At present, many national or industrial standards have been formulated. From the technical content of the standard, the general product standard has grade requirements, but other types of products do not. At the same time, in the requirements of health indicators, general products are more stringent than pollution-free foods. Green food: refers to pollution-free, safe, high-quality and nutritious food produced in accordance with the principle of sustainable development and specific production methods. It is approved by specialized agencies to use the green food mark. Green food sets standards for the quality of production environment, production materials and production operations. In its standard, the pesticide residue limit value is formulated with reference to the indicators of the European Union. Organic food: Organic food comes from the organic agricultural production system, is processed according to international organic agricultural production requirements and corresponding standards, and is certified by an independent organic food certification body. Organic agriculture is a production system that does not use synthetic substances such as chemical fertilizers, pesticides, growth regulators and feed additives for livestock and poultry, nor does it use genetically engineered organisms and their products. Experts pointed out that this arrangement is based on its safety as the main standard, and the nutritional quality of products may not be higher. At present, there are three aspects of vegetable quality and safety: pesticide residue, excessive heavy metal content and high nitrate and nitrite content. The main reasons for the excessive content of heavy metals in vegetables are the unreasonable discharge of industrial "three wastes" and urban garbage, which causes the pollution of planting environment, thus causing the excessive content of heavy metals in vegetables, especially lead and cadmium. In addition, the extensive use of organic fertilizer made from livestock manure is also a reason, because some feeds have additives containing heavy metals. The content of nitrate and nitrite in vegetables exceeds the standard, which is mainly caused by some farmers' unreasonable use of chemical fertilizers in pursuit of yield. At the same time, the unreasonable use of organic fertilizer will also cause the accumulation of nitrate content in vegetables. In addition, the content of nitrate in vegetables is also related to soil phosphorus deficiency and light intensity, which can increase its content. According to Zhu Tianzong, former technical deputy director of the Institute of Pesticide Testing of the Ministry of Agriculture, different vegetable varieties have different prevention and control methods because of their different occurrence laws of pests and diseases, and the pollution degree is relatively light and heavy. Some vegetables and fruits that are easy to be infected with insects and difficult to control after being infected with insects are often varieties with serious pesticide pollution. According to the comprehensive analysis of pesticide detection results in vegetable markets around the country, Chinese cabbage (Chinese cabbage, green vegetables, chicken feathers), leek, cucumber, cabbage, cauliflower, kidney bean, mustard, chrysanthemum, water bamboo and so on are seriously polluted by pesticides, among which leek is the most polluted by pesticides. Because of the strong drug resistance of Pieris rapae, it is difficult for ordinary pesticides to kill pests. In order to kill pests as soon as possible, farmers will choose highly toxic pesticides. Leek maggots, pests of leeks, often grow in vegetables, and it is difficult to spray pesticides on the surface, so many farmers irrigate their roots with highly toxic pesticides. The drug abuse characteristics inside leeks make poisons spread all over the whole plant. At the same time, leeks irrigated with highly toxic pesticides often grow luxuriantly, with plump leaves and dark green colors. Experts remind that eggplant vegetables such as green peppers and tomatoes, melon vegetables such as wax gourd and pumpkin, tender pod vegetables such as beans, bulbous vegetables such as onions, garlic and onions, tuber vegetables such as potatoes and yams are relatively less polluted by pesticides. Not all wild vegetables are green food. In recent years, with the rise of the concept of "green consumption", wild vegetables are gradually favored by the public. Many people think that wild vegetables grow naturally and should be the safest and most "green" food without using chemical fertilizers and pesticides. Some vegetable vendors in farmers' markets seized the public's fear of pesticide residues and declared that "wild vegetables are completely pollution-free" and are green food. Many citizens are also convinced and have bought it. Some citizens simply take advantage of the spring outing to dig wild vegetables in suburban fields and farmland. Is there really no pollution in wild vegetables? He Qiwei, director and researcher of Vegetable Research Institute of Shandong Academy of Agricultural Sciences, pointed out that this statement is not scientific. Because green plants can purify the atmosphere, they can not only absorb dust and suspended matter in the air, but also filter harmful gases and chemical components in the air and soil. If these wild vegetables grow in polluted areas, they are naturally polluted and it is difficult to clean up the pollutants. If you eat contaminated wild vegetables, it will do harm to your health and even cause food poisoning. Some wild vegetables that grow vigorously often grow near garbage dumps or polluted rivers, because these places are particularly rich in "nutrients". Experts also pointed out that wild vegetables grown in a pure natural environment are relatively safe and can be safely eaten if there is no pollution source nearby, no pesticides are applied to crops around and the soil is not polluted. In the market, vegetable sellers often say that their vegetables are "greenhouse vegetables", which is basically equal to pollution-free vegetables. Experts believe that this statement is not completely correct. Many people think that greenhouse vegetables are generally produced in winter, and it is freezing outside, with fewer insects and less pesticides. However, there are many pests in open vegetables, and pesticides are often toxic. Others say that vegetables in greenhouses are generally more sick and less insects, and even if they are used, they are bactericidal pesticides, often with low toxicity. Although there are few pests outside the greenhouse in winter, the high temperature in the greenhouse does not affect the occurrence of pests, and the harm is no less than that of open vegetables. The most important point is that under the same conditions, the degradation rate of pesticides in greenhouse is slower than that in the open field. At present, the safety interval of vegetable medication in China is mostly the standard under open field conditions, which may not be applicable to greenhouse vegetables. In addition, it is not accurate to think that bactericidal pesticides are efficient and low toxic, and some fungicides are not low toxic. And at present, most of our pesticide residues are pesticides, and fungicides are difficult to detect, but it does not mean that there is no danger.