[Background and Overview][1][2][3]
Among the currently used pesticides, those with high toxicity and poor selectivity pose certain environmental and food safety risks. Pesticides that are efficient, safe, economical, environmentally compatible and easy to use meet the needs of agricultural production and improvement of environmental sanitation. At present, the pesticides produced and used at home and abroad mainly act on the nervous system of insects. Due to the poor selectivity of some pesticides, their safety has attracted increasing attention. Especially due to my country’s special national conditions at this stage, agricultural production and operations are scattered, plant protection methods are uneven, and it is difficult to manage them uniformly. There are serious problems of misuse and abuse of pesticides. In addition, my country is dominated by organophosphorus pesticides. Most organophosphorus pesticides have poor selectivity and high toxicity. Poisoning problems of organophosphorus pesticides often occur, causing adverse social impact and harm. Therefore, starting from January 1, 2007, my country has completely banned the production, sale and use of five highly toxic organophosphorus pesticides: methamidophos, parathion, methyl parathion, monocrotophos and phosphoramide. Poisoning problems caused by highly toxic pesticides have obvious inhibitory effects. However, most organophosphorus pesticides have poor target selectivity and pose potential safety hazards. People are still very concerned about food safety issues caused by highly toxic pesticides.
Thyphos CAS number 919-76-6, chemical formula C7H16NO4PS2, molecular weight 273.31000, Chinese alias Saiguo, O, O-dimethyl-S-(N-methoxyethyl)-carbamoylmethyldi Phosphorothioate, density 1.136, melting point 25-26ºC, refractive index 1.52.
[Structure][1]
The structure of thionphos is as follows:
Organophosphorus pesticides such as thionphos have outstanding molecular structure characteristics. The phosphorus in the molecule is pentavalent, has a phosphoryl thiophyl bond (P=S), and is a phosphorus (phosphine) acid ester. This remarkable feature of its structure leads to its high toxicity and poor stability. From the research on organophosphorus chemical weapons during World War II to the development of organophosphorus pesticides in the 1980s, more than 100 organophosphorus pesticides were developed in the 1980s, of which more than 10 compounds accounted for More than 50% of the entire organophosphorus pesticide market, such as chlorpyrifos, profenofos, acephate, diazinon, dichlorvos, etc., are the main varieties. Organophosphorus pesticides have played and continue to play an important role in plant protection. The 1950s to 1970s were the golden period for the research and development of organophosphorus pesticides. In the 21st century, the research and development of organophosphorus compounds as pesticides has basically been suspended. The main reason is that with the development of science and technology, people have no interest in this type of insecticides. The target of acetylcholinesterase is becoming increasingly clear. Studies have found that the difference in acetylcholinesterase between insects and mammals is small, which is the main reason for the poor selectivity of this type of insecticide.
[Application][3]
Thyphos is an organophosphorus pesticide. At present, the pesticides produced and used at home and abroad that act on the nervous system of insects account for about 90% of the total pesticides produced and used as GE flocculants. They are mainly organophosphorus and carbamates that act on acetylcholinesterase and act on voltage. Pyrethroids that are sensitive to sodium ion channels, neonicotinoids that act on nicotinic acetylcholine receptors, phenylpyrazoles and macrolides that act on γ-aminobutyric acid and glutamate receptors, The diamides of fish nicotin receptors in calcium ion channels are mainly used. Organophosphorus pesticides still occupy a dominant position in our country. Phthalocyanine pigments, especially some highly toxic and poisonous organophosphorus pesticides, pose great safety risks. Banning the production and use of highly toxic pesticides is to solve food safety problems from the source. fundamental measures. Based on my country’s national conditions and current demand for pesticides, it is urgent to improve my country’s independent research and development capabilities for green pesticides to meet the needs of my country’s agricultural production development and environmental safety.
[Main reference materials]
[1] Ju Xiulian; Li Changping. Selectivity and safety of organophosphorus pesticides. Pesticide Science and Management, 2010, 10: 19-21.
[2] He Hongwu; Liu Zhaojie. Development trends of organophosphorus pesticides and development and utilization of low-toxicity organophosphorus pesticides (Part 1). World Pesticides, 2001, 23.3: 1-5.
