China's annual pesticide use of 3.37 million tons, each person can share about 2.4 kg, China uses 8% of the world's arable land to feed 22% of the world's population, while using 47% of pesticides. In the fruit and vegetable tea census carried out in 2018-2019, more than 660 kinds of pesticides were found, but the monitoring plans and pesticide types of various departments were up to 121, which means that the actual types of pesticides used far exceeded the monitoring, and may exceed 800.
In addition to herbicides, chemical pesticides are also a large number of pesticides, and chemical insecticides are mainly divided into the following types from the method of insecticide:
Gastric agents: organophosphorus insecticides, such as enemy insects, spray plant leaves, pests feed, absorbed through the stomach and intestines, poisoned and died.
Contact killers: Leguo, permethrin agents, pest stubble agents of the epidermis or stomata penetrate into the body, poisoning and death.
Systemic insecticides: phosphorus methion, pests are absorbed into the plant through the leaves, stems, roots or seeds of the plant, and in the plant body to channel, diffuse, retain or produce more toxic metabolites, pests suck or eat, poisoning and death.
Fumigation: aluminum phosphide, at room temperature, the agent is gaseous or decomposed into a gas state, through the action of insecticides from the pest's respiratory system into the body, poisoning and death.
Sterile Agents: After agents such as thiotepipe enter the worm through the pest wall or digestive system, the normal reproductive function is destroyed, so that the pest cannot reproduce offspring, this method of infertility includes male infertility, female infertility and sexual infertility.
These pesticides pollute the environment, destroy the land and affect people's health.
Take organophosphorus, the agricultural development of countries around the world is inseparable from organophosphorus, in China, organophosphorus is also widely used, one of the largest amount of pesticides. Dichlorvos, dimethoprim, leguo, methylphosphorus, etc. all belong to the family of organophosphorus pesticides.
The predecessor of organophosphorus pesticide is a chemical weapon. German scientist Schrader, because of the poisoning experience, synthesized the first organophosphorus insecticide, because the strong toxicity was quickly used by the army, the World War II Tabun bomb. Organophosphorus compounds enter the human body through the respiratory tract and skin, and the muscles of poisoned patients cannot stop trembling, vomiting, incontinence, and even delirium, coma, and when severe, lead to death.
In 1997, the Signing of the Chemical Weapons Convention came into force, the total ban on chemical weapons, organophosphorus because of its strong and efficient insecticidal capabilities, in the field of agriculture, the world's 50% of chemical pesticides are organophosphorus.
In the 1980s in China, the number of pesticide poisonings was higher than 100,000 per year, and the number of organophosphorus pesticides was the majority. Among them, the number of daily pesticide poisoning is 4-5 times higher than that of productive pesticide poisoning, and the mortality rate is as high as 12%.
The toxicity of organophosphorus is mainly reflected in the inhibition of acetylcholinesterase. Acetylcholine is a neurotransmitter that causes sustained excitation of the associated nerves if a large aggregate causes the corresponding target organ to fail after being excited. Organophosphorus poisoning leads to spasm of the bronchi and an increase in secretions, and if left untreated, severe cases may lead to respiratory failure.
Acute organophosphorus poisoning is divided into 3 grades:
1. Mild: Nausea, vomiting, dizziness, headache, sweating, chest tightness, fatigue, blurred vision and miosis
2. Moderate: In addition to the above symptoms, mild dyspnea, muscle tremor, and significant pupillary contraction begin to appear
3. Severe: severe central nervous system disorders, such as coma, cerebral edema, etc., and there are severe breathing difficulties, pulmonary edema, generalized muscle rigidity and other manifestations.
Chronic organophosphorus poisoning due to irregular operations, inhalation in the process of production and drug application, etc., can lead to depression and anxiety, which in turn leads to death associated with these mental illnesses.
There is a village called "Budi" in India, where 80 people have committed suicide in 3 months, and each of the 320 families in the village has at least one person who has died by suicide. The emergence of "suicide villages" may be related to the excessive use of local organophosphorus insecticides.
In children aged 5 to 15 years, ADHD is positively related to elevated concentrations of organophosphorus in the urine. Studies of 7-year-olds have found that organophosphorus insecticides affect children's cognitive development, motor nerves, memory and IQ development, and even affect the normal development of brain structures.
Eating food contaminated with insecticide can double the rate of chromosomal abnormalities in peripheral blood cells. Adults consume foods sprayed with pesticides, raising the risk of diabetes and Parkinson's disease.
In 2018, Harvard studied the relationship between high pesticide residues and infertility: Women who ate high pesticide residues were 26 percent less likely to have a successful pregnancy, and eating pesticide-containing agricultural products also affected male infertility.
Pesticide residues are not only harmful to buyers, but also to farmers who spray pesticides, which cannot be excluded from the body and slowly accumulate, endangering themselves and endangering the next generation.
The Ministry of Agriculture and Rural Affairs said that it will launch a three-year action of "curing prohibited, controlling drug residues, and promoting upgrading" of edible agricultural products, and eliminate the existing 10 kinds of highly toxic pesticides in stages and batches, especially for highly toxic pesticides with more residues on vegetables. The state should deal with highly toxic and prohibited pesticides, and strengthen the research and development of maximum residue limits and daily allowable intake standards for pesticides, so that these important standards related to the public can reach the level of advanced countries in the world.